View Full Version : Determinism or Indeterminism
We are touching here on a subject that has been addressed since the very beginning of constructive rational thought. However I believe that we are living in a time where it will find its final solution.
To open the discussion I would like to refer to the work of Ilya Prigogine, a Belgian (yes we have some good scientists to ;) ) scientist who made his contribution in the field of thermodynamics and received the Nobel Price of Chemistry for it.
His work primarily focussed on thermodynamics far from equilibrium and irreversable processes. He also made a lot of contributions to the fairly new field of deterministic chaos.
In deterministic chaos we find that some systems (non-equilibrium systems) experience behavior that the tiniest change of the initial conditions results in totally diverse solutions. This is also known as the butterfly effect : the flapping of the wings of a butterfly in the amazoneforest could result in a huge storm in Europe.
If this is the case why are we still talking about deterministic chaos ? Because if you input exactly the same initial values (exaclty is in infinite presision) you get the same results. You would expect that the determinists have won the day because even in something as random as 'chaos' there still is determinism.
Where does this determinism come from ? Time symmetry !
All basic equations from Newton through Einstein and quantum mechanics are time symmetric. This means that if you replace t with -t, the equations remain the same. It makes no difference for a particle or a wavefunction if time goes to the past or to the future.
Where does the apparent arrow of time come from ? The second law of thermodynamics states that entropy always increases as time increases. This however is like an ad hoc proposition that we have allowed to exists but actually describes our lack of accurate measurment. It was believed, when the laws of thermodynamics were formulated, that the individual particles that interacted still obayed Newtons timesymmetric and deterministic equations but we had to resort to statistical formulations because of our inadiquacy of measuring. Entropy is then the value that expresses our ignorance of the system. This was accepted as a temporary standback since after all, the particles were very small (10^-10 m) and there were a lot of them (10^23 particles in a mol of gas)
However something very disterbing happened near the end of the 19th century. There was a particularly nasty problem going on in the field of celestial mechanics namely the three body question. Newton had touched upon it but left it wisely for others to solve, it stayed with the theoretical physicist all through the eighteenth and nineteenth century until Poincaré, the famous French mathematician (who almost beat Einstein the the formulation of special relativity), proved that it could not be solved ! The three body system proved to be highly unstable and led to chaotic behavior. This is of course a very disturbing, if even something as simple as three body interaction is a source of chaos how on earth are we ever going to solve the chaos that reigns at a molecular level in gasses ?
The solution that Prigogine proposes actually is quite simple.
Normally solutions of systems can be shown in something called fase space. This is an imaginary space where one can plot all the observables involved like position and impuls to show the solution of the equations of motion. For example periodical movements like an idealised pendulum are represented by a circle in fase space. This fase space in Newtonian mechanics is actually a Hilbert space, this is an Euclidian space with an infinite amount of dimensions.
What Prigogine proposed was to generalise Hilbertspace in order to allow distribution functions in stead of trajectories to represent the solution. Once he did this, chaos turned to order again and he could actually solve the non linear equations. In doing this something else was solved as well : the time symmetry was broken ! As it turned out the generalised Newtonian equations carried the arrow of time in them and allowed for an explantion of the second law of thermodynamics.
Why have the laws of Newton been so succesful ? What are the criteria that makes them break down ? It turns out that persistent interactions as opposed to transient interactions are the key. A transient interaction is when two free particles meet, interact and are free again. However this is an idealisation in nature there is no such thing as a 'free particle' what actually happens is : a particle interacts, flies a bit, interacts again and this never stops. This last kind is called persistent interaction and is the very reason for chaos and irreversebility.
What we have to come to grips with is that probability is actually something that has found its way into our basic equations. This however doesn't mean that nature will stay forever a mystery to us, quite the contrary : by accepting the inherent probabilistic nature of the universe we have found a new way of questioning it and finding new and interesting answers. Life isn't deterministic but also not a total random event, it is a narrow path between the two.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Adlerian
05-05-00, 12:26 AM
Plato: I hope you get a lot of responses on this but perhaps you're too far ahead for our audience. I'll bite though.
This is not my given field but I fail to see how what you have said translates into existence being something in between deterministic and indeterministic. Existence is both as I see it but the way in which it is indeterministic is in the realm of human existence, hence choice (and personal responsiblility). Nature itself seems completely deterministic in every other way.
Heisenberg was wrong, by the way, God doesn't play dice.
Please elaborate...
Adlerian
Adlerian,
how can a deterministic nature give rise to an indeterministic human ? This is a logical contradiction !
Actually this duallism has plagued phylosophy and theology all through history. Where does this believe in nature as an automaton come from ? I think it is partly because we always made a clear distinction between "living" and "non-living" matter. The distinction is at one side a natural one because what can be more distinct than a stone and a human ?
However it results in a whole range of difficulties when one wants to apply logic to it. The reason for living things to be alive has always been some kind of divine spark that animated it. This however alienated us from the very universe that we inhabit. It is as though we are foreign visitors who are thrown on this world and have nothing in common with it.
Once we put probability into nature itself, we find ourselves in a whole different universe ! One that welcomes and anticipates live, one (I dare say) in which life is inevitable !
When I say that life follows a narrow path between determinism and total randomness I mean that probability doesn't mean total randomness ! There is only one such probability function that describes total randomness and it is the flat probability. There is a whole range of other probability functions out there even ones who very closely resemble the certainty of delta functions.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Hi Plato,
I'd have to agree with Adlerian here (from a personal point of view). I also believe that nature is determined and governed by laws that predict its future and actions in a very good way.
The key in my reasoning that nature is deterministic is exactly what you've already written when talking about entropy: simply because we do not have the conceptual and mechanical power to calculate every movement of every molecule of a mole of gas, we create a statistical model that describes all the particles as eg. a point or a rigid spherical body. Everything we know in physics is based on a certain way of representing matter and its interactions in a simple model that we can compute. When creating a model, you are forced to leave out certain aspects of nature (minor side-effects). A good example is, also as you already mentioned, the ideal pendulum (harmonic oscillator). If you damp the oscillation a bit and add an external force, you can approximate the differential equation to the first order (sin -> x), and you can easily get some results. But those results are not consistent with what you see in the lab, so you decide to take another term in the approximation of the sine (sin -> x - x^3/6). And all of the sudden effects that you'd never expect (hysteresis in fase/amplitude diagrams) appear. This is also a form of chaos (the reaction of the oscillation to the external force depends on what you did before), but does this necessarily mean that the damped oscillator with external force behaves chaotically ? I don't think so: we simply have to take all the order terms in the approximation to get a complete result.
(sidenote: this is a silly example and definitly not fundamental enough, but i thought it might illustrate my point :)).
About the three-body problem: ask yourself why there is a non-lineair differential equation to solve in the first place ? It's because Newton (or Poincare, or whoever) described the interactions between those three bodies using a mathematical model. They had to resort to this model because it is impossible to describe all the n*10^23 particles in differential equations. The probability in nature is not a characteristic of nature itself, but, as you said yourself, a manifestation of our own ignorance.
Life is something similar. What makes us think or do things ? On a molecular level this is just a chemical reaction between organic compounds (to quote Pacino from "The devil's advocate" here: "love is chemically equal to eating large quantities of chocolate" :)). If we know exactly how many chemical reactions take place inside the brain and how all the particles, molecules interact, we must be able to predict how a human being will react. But we can't, so we say a human being behaves chaotically and indeterministic.
(Tricky subject by the way, since I don't think we already know if there's such a thing as a "human soul" (the spark of life)... Perhaps Boris can enlighten us a bit here).
As I see it, the question we have to ask ourselves before saying nature is indeterministic, is what matter is really made of. They aren'tlittle spheres of mass and charge. They also don't seem to be some sort of wave... These are all mathematical models that are not accurate enough, so the question whether nature is (in)deterministic is not yet to us to answer... I'll stick for deterministic for now :).
Bye!
Crisp
I'm sorry Crisp but you told me nothing new. Again I have to say it makes no sense, how can time symmetric laws give rise to irreversible processes ? This is impossible and self contradictory !
Actually the argument is quite simple to be verified. We need an experiment that verifies a prediction of the changed laws that is not predicted by the classical laws. I will have a look on the net if I find something that does this very thing or that proposes such an experiment.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Hi Plato,
I totally agree that time-symmetric laws cannot predict irreversible processes. But the point I tried to raise (and, after rereading I have to admit it got totally lost somewhere ;)), is that from this observation (and others) you conclude that nature behaves indeterministic. I would simply say that the laws we have are wrong, and once we find a set of laws that have the direction of time implemented in them, nature would be deterministic again (to put it very simple, I know there are some complications).
Correct me if I am wrong, but your point on this is "our current laws of physics cannot predict the indeterministic behaviour of nature, and there are very good indications that nature actually is indeterministic", right ? (Just to be certain we're at the same wavelength here).
Bye!
Crisp
[This message has been edited by Crisp (edited May 05, 2000).]
Plato,
Enlighten me please, but how is it that a process is termed "irreversible"? Is it because the process is modelled by a set of functions that map a single point in configuration space (initial parameters, in other words) to an entire region of phase space, and the mapping is not 1-1?
But there is a big difference between observing a property of a model (such as irreversibility), and claiming that the reality described by the model in fact intrinsically possessses such a quality. We have to look before mere formulae, and remember that the formulae are models, not "laws". The only Laws there are, are summarized in the axyoms used to construct the models. However, a model typically involves much more than a set of axyoms; namely, in modeling physical reality we often neglect or simplify large swaths of it. So when our limited model predicts that two distinct sets of initial conditions result in the same outcome, all it means is that the outcome is only identical because we neglected some finer details of the interaction; were we to dig deeper, we might discover that the "identical" outcomes only look similar, but indeed are distinct and distinguishable, at least in principle. What does it mean when a one-to-many relationship is defined between initial configurations and final outcomes? All it means is that there is noise in the system that deflects a trajectory under ideal conditions so that the result is a distribution of trajectories. However, a distribution is merely a result of the fact that we model the noise as a distribution; it is impossible for us to determine precisely what the noise will be at any moment in time -- however, that does not mean that at any moment in time the noise does not possess a definite, and indeed deterministic, value.
As to the problem of disentangling determinism from free will, I am afraid I've done an indadequate job at ruining your day on that particular issue. :D Let me correct that particular mistake right here and now.
Let's assume that you are right and the universe is indeed nondeterministic at the fundamental level. Then, of course, you have the problem of explaining how the large-scale world we observe is so sharply defined and causal. But even allowing that you found an ingenious explanation for how order arises from chaos (and not the other way around, which would be the position I'm trying to argue), you must observe that both the brain and indeed the cells from which it is built, are large-scale objects. As such, they do not suffer from the quantum "indeterminacies" of the subatomic realm. As sure as a rock that flies when you throw it, a neuron will fire when stimulated. Even at the level of individual synapses, we are dealing with effects of thousands, if not millions, of neurotransmitter molecules acting simultaneously, so that their individual "random" behavior gets averaged into a very predictable and dependable outcome. So even the behavior of an idividual synapse is as deterministic as that of a transistor in an electronic circuit. Now, consider that brain activity is a resultant of many, often redundant, computational units summed together -- so that additional averaging and smoothing occurs even beyond the molecular level. I am afraid that when you look at the cognitive machine as the high-level result of brain activity, it is therefore deterministic for all practical purposes even if the underlying substrate is not (and I claim that it is.) Similarly, when you consider the interaction of that cognitive machine with the environment, you must understand that we are always dealing with smooth averages and therefore sheer determinacy. Even if you assume that at the subatomic level the universe is nondeterministic, you still cannot escape the conclusion that determinacy rules at the large scale, and therefore governs our very nature as human beings.
But going back to the issue of what comes first: order, or chaos -- I choose order. This is simply because in such a scenario we indeed know that chaos still arises in a sufficiently complex system (e.g. at least 3 orbiting bodies), and everything we observe sounds like a possible outcome. If, on the other hand, utter chaos stood at the foundation of reality, then a question must be asked how that chaos manages to acquire deterministic characteristics at any scale whatsoever. I have yet to see even a hint of a satisfactory answer to that question.
------------------
I am; therefore I think.
Crisp,
Yes, you are correct, I claim that our current laws are incomplete in so far that they don't show the order that arises from chaos, which we can observe in a range of experiments (e.g. Belousov-Zhabotinski reaction) and has been called the self organisation of dynamical systems.
Boris,
I mean irreversible as in having a distinct arrow of time in the basic equations that provides a different answer for t and -t. This could indeed be shown as going from a point to a region in fase space.
A simple example is diffusion in gasses, a mixture of two gasses will never "unmix" itself by itself.
A much more dramatic example is the conception and consequent growing of a human embryo. There is absolutly zero chance that this new being will unconceive itself into an eggcell and a sperm again. This is one of the most beautiful examples of self organisation and irreversibility.
You see chaos only reigns at the trajectory level of the description in fase space, if you go to probability description you get order.
Perhaps a small example can illustrate my point more clearly. I am taking this from Prigogine's book "The end of Certainty" which is a very accessable and interesting book which I recommend very much.
Take the recursive equation : X_(n+1) = X_n + 1/2 modulo 1 (X_n means variable the n'th solution of the recursive formula)
This has a very predictable and periodical behavior, for example take X_0 = 1/4 then we have X_1 = 3/4, X_2 = 5/4 modulo 1 = 1/4 and so on. In stead of considering individual points we can examine ensembles of points which I write as P(x), this is the probability distribution of x. A trajectory discription then corresponds to a specific distribution called a delta function, it can be written as P_n(x) = \delta(x - x_n) (with \delta being the greek letter, it is a function that vanishes for all values of x exept x=x_n)
We can formally write the relation between P_n and P_(n+1) as P_(n+1)(x) = U P_n(x). U is the so called Perron-Frebenius operator which for example in quantum mechanics is used to describe the time evolution of a system.
As a special case for trajectories we have :
\delta(x - x_(n+1)) = U \delta(x - x_n), this is exacly the same equation as the first. There are no solutions that cannot be expresed in terms of trajectories. This is the case for a periodic map, if we take a chaotic map like the Bernoulli map we get the following equation :
x_(n+1) = 2x_n modulo 1. This is a deterministic equation because once we know x_n we also know x_(n+1) however every non rational number will result in utter chaos, deterministic chaos. One could argue that the result is still periodical but with an infinite period. We can show that any number will be arbitrarily close approached after an infinite amount of time. We have a dynamical system leading to randomness.
If we swich back to the statistical formulation of the Bernoulli map we get a totally different view, after 4 steps the function finds stability in a flat distribution. The chaos is gone ! The equivalence between the statistical description and the trajectory description is broken. After only 4 steps we already know the system has a flat distribution and is therefor completly random, this knowledge we find only after an infinite amount of iterations in the trajectory description.
This is only a very simple example of course, it show that probabilistic descriptions actually provide more information than trajectory descriptions.
Boris, I'm utterly shocked to hear from you that you describe the brain as deterministic while it is the 'example par excellence' of self organisation from randomness ! We have neurons transmitting information to each other in an apparently random way while the endresult is a coherent thought process. Although coherent is even not really at its place here, if we stop and follow our thoughts for a moment about anything they follow a really strange path of associations and eliminations of nonsense. This has nothing to do with determinism, cause this would mean I could somehow unthink a certain idea that just occurred to me. This of course is utter nonsense.
I claim there is no comparison what so ever with the turing machines that our computers are and the selforganising processes that go on in our brain.
The apparent determinism as you call it would have a very big problem if for example suddenly a part of the brain would function any more because of a tumor or some other throumatic event. However apart from some severe headaches, the person still has the capacity of most of its cognitive processes. There is no way a deterministic system can handle this.
It seems to me that people have concentrated to much of the negative aspects of chaos. It also has a negative connotation, however during the past decades it has become more and more apparent that chaos is actually very positive. That is the way life and evolution works. I would like to refer here to the work done in micro biology and how quasi species provide mechanisms for evolution.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Meta physical plea for indeterminism.
First of all I would like to point out that being a atheist I don't like order as a prerequisit for obtaining a universe. This reeks to much after a god concocting it all.
Second I claim that in a deterministic universe time doesn't really exist as such. What is time ultimatly ? It is something that is very closely related with change however nothing really changes in a deterministic universe. I mean by this that if you know all the preconditions to the infinite decimal point, you know everything there is to know and can predict the future and reconstruct the past. This means that each timeslice of the universe holds in itself all the information of all other timeslices. Therefore I would call time an illusion in a deterministic universe (as did Einstein on several occasions).
However time as in change is the basic dimension for our existence, if there is no change, there is no existence. The non existence never changes for there is nothing to change, everything that doesn't change (and I mean never as in through all time) doesn't really exist. So a deterministic universe doesn't exist !
This looks like one of those nasty syllogisms but actually it isn't. If you think about it determinism take away everything that makes life worth living, it puts life on the same level as death. It puts existence on the same level as non existence and that is actually a contradiction.
Something else that strikes me in the believe that it would be possible to know everything is that this very much resembles the Icarus story. It is a longing to become God, to be able to obtain immortality and become detached from the universe itself.
It is also a disturbing belief in the controllability of the universe or in society it is something that could serve very well as a bases philosophy for a totalitarian regime. This also has a very strict set of rules and tries to mold society in that way. The reason why these regimes never succeded is ultimatly because the universe is not governed by strict laws but it rather searches its own way.
In eastern philosophy nature is something that is not describable by laws but rather something that becomes by itself. I like this very much, I also think that eastern philosophers and religious thinkers are much less antropocentric then our western thinkers who ultimatly always need some form of intelligence who is behind everything. Cause after all God is the ultimate antropocentricity that we assign to nature...
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Plato,
I can't believe I am about to lecture a physicist about the foundations of his own trade, but I am getting a distinct impression that you are not hearing what I'm saying. So, for better or worse, here it goes...
I mean irreversible as in having a distinct arrow of time in the basic equations that provides a different answer for t and -t.
This could indeed be shown as going from a point to a region in fase space.
A simple example is diffusion in gasses, a mixture of two gasses will never "unmix" itself by itself.
Ok, let's dwell on that one for a while. If the collisions between gas molecules are perfectly elastic, then indeed we can build a simulation of an arbitrary number of of gas molecules, take it through some n state updates, then exactly reverse the momenta of all the molecules, and watch the system re-establish its initial conditions. Deterministic indeed.
Of course, in real life the collisions are not perfectly elastic; every now and then energy is leaked and absorbed as photons. If we were to simulate the system to that level of detail, then to reverse it we would need to reverse the outbound photon trajectories, as well as make sure that subatomic particles are simulated at a sufficient level of detail that they will remember what happened to them in the past, so that they can re-enact such events in reverse if we reversed the momenta of their respective components. Of course, here we are faced with the problem of deterministically simulating both photons and other "particles" of matter/energy -- and so far, we do not possess sufficiently detailed models to do so (in fact, all we currently possess are crude models that describe the statistics of trajectories, rather than the actual mechanisms causing the trajectories.) So you may cry foul all you want, and for now you are right -- deterministic computational understanding of reality at all levels is currently nonexistent. However, I would not vouch for the future if I were you.
A much more dramatic example is the conception and consequent growing of a human embryo. There is absolutly zero chance that this new being will unconceive itself into an eggcell and a sperm again. This is one of the most beautiful examples of self organisation and irreversibility.
Nothing but a more complex version of mixing gases. Still the same type of matter/energy, still complex inelastic reactions, still complex interactions with environment, but every one of those reactions and interactions are causal and therefore deterministic.
You see chaos only reigns at the trajectory level of the description in fase space, if you go to probability description you get order.
I said it before, and I'll say it again. There are two kinds of knowledge: applied, and theoretical. The former is more concerned with what is observed, and doesn't care as much about how the observations are brought about. The latter is concerned with the mechanisms that give rise to trajectories. You seem to be having trouble separating the two kinds and realizing that their objectives are quite different -- even though both fit equally well under the aegis of science. The primary difference, I suppose, is that you can always derive a probabilistic description from a trajectory description, but not the other way around. So you ought to realize that one of these levels of description is more fundamentally powerful than the other (although not necessarily more usable or indeed useful in applied endeavors.)
We have a dynamical system leading to randomness.
If we swich back to the statistical formulation of the Bernoulli map we get a totally different view, after 4 steps the function finds stability in a flat distribution. The chaos is gone ! The equivalence between the statistical description and the trajectory description is broken. After only 4 steps we already know the system has a flat distribution and is therefor completly random, this knowledge we find only after an infinite amount of iterations in the trajectory description.
This is just what I've been talking about. Sure, a statistical description may provide you with some useful insights about the system, but it will never allow you to understand how the system really works, what are the rules that guide its intrinsics. In fact, if you wanted to know that, you'd have to somehow discover the formulaic definition of the Bernoulli map -- and once you do, then you will have gained knowledge of how the system works, not just what the results of all that work look like.
This is only a very simple example of course, it show that probabilistic descriptions actually provide more information than trajectory descriptions.
Here, you are confusing amounts of information with types of information. The statistics of outcomes vs. trajectory descriptions are not referring to the same qualities of the system; they are not mutually exclusive but in fact complementary. However, you must note that you would never be able to derive a statistical description of the system unless you first knew the deterministic formulation of what the Bernoullli map is in the first place. This is the difference in descriptive power I've been trying to point out all this time.
Boris, I'm utterly shocked to hear from you that you describe the brain as deterministic while it is the 'example par excellence' of self organisation from randomness !
What randomness? Neither the components of the brain, nor of the environment within which it develops and functions, are random; they all follow the same set of laws, and they are all driven by causal interactions. Causality == determinism, n'est-ce pas?
We have neurons transmitting information to each other in an apparently random way while the endresult is a coherent thought process.
Apparently random, but not actually random. Consider, if you knew nothing about computers, and were given a chance to observe real-time contents of registers in the CPU, what your conclusion would be as to the nature of the process that changes those contents. You'd probably say it was random -- at least that's my guess. All the while, we know that particular process is deterministic as can be.
I keep making analogies between computers and brains, largely because it is indeed true that fundamentally they are the same -- deterministic information processors. Yes indeed, the brain is a rather sophisticated Turing machine. You must have missed that bit I wrote about the utterly deterministic input/output behavior of neurons. An entire branch of science is burgeoning due to that fact, called neural computation. Wellcome to the year 2000!
This has nothing to do with determinism, cause this would mean I could somehow unthink a certain idea that just occurred to me. This of course is utter nonsense.
Plato, you can no more unthink an idea, than a broken Humpty Dumpty can reassemble itself. Remember that funny branch of science called thermodynamics? Time never reverses itself. The only way to achieve a complete reversal of the system, is to simultaneously and precisely flip all of its momenta -- which is statistically next to impossible for most systems, and physically impossible altogether (because everything is causal, and in a closed system a complete reversal cannot occur spontaneously.) Hence, the "arrow" of time. What would we do without inertia, eh?
I claim there is no comparison what so ever with the turing machines that our computers are and the selforganising processes that go on in our brain.
A brain can, at least in principle, be modelled at an atomic level on a computer. Anything that can be precisely modelled on a computer, is a computational process and is describable by a Turing machine. Like it or not, brains are Turing machines. Otherwise, you are going to have to provide me with a fundamental (and not just practical) reason why a brain cannot be completely functionally simulated on a computer.
The apparent determinism as you call it would have a very big problem if for example suddenly a part of the brain would function any more because of a tumor or some other throumatic event. However apart from some severe headaches, the person still has the capacity of most of its cognitive processes. There is no way a deterministic system can handle this.
Now you are treading on ground that will burn your feet. In fact, the brain is severely vulnerable to injury, and most brain traumas that take out a region of the brain indeed result in disability (which is the more severe the larger the disabled chunk of the brain is, and the later in life the injury occurs.) Some aspects of cognition are relatively robust to injury, but only as long as only peripheral functionality is damaged; every brain process has a critical brain region without which it can no longer function at all. Some of the brain's robustness is due to its holography-like representation of information, where data is not stored in fixed locations, but rather is spread out across a network of storage devices; taking out part of the network in such situations will not destroy the data, but only degrade it a little bit. This has been demonstrated quite convincingly with many computational neural network models. In fact, these days one of the standard methodologies in neural network research, is "lesioning" a part of the network, and observing the effects of the lesion on the network's performance (which is essentially a measure of how localized vs. distributed the network's representation is). Another feature that helps the brain witstand injury is the reduncancy of many functions due to its bilateral symmetry -- similar to how your body is somewhat resistant to injury due to the fact that you have a backup kidney, a backup lung, a backup eye, etc. in case one of them gets damaged or destroyed.
So indeed, you can't be more wrong. The brain is a deterministic system, and deterministic brain models are taking lightyear strides in the enterprise of understanding cognition. For some discussion on the deterministic and material nature of the brain, as well as some mention of interesting brain pathology results, see the <A HREF="http://www.exosci.com/ubb/Forum8/HTML/000245.html">souls...................oh Boris </A> thread in the Religious Debate forum.
It seems to me that people have concentrated to much of the negative aspects of chaos. It also has a negative connotation, however during the past decades it has become more and more apparent that chaos is actually very positive. That is the way life and evolution works. I would like to refer here to the work done in micro biology and how quasi species provide mechanisms for evolution.
Once again, nobody is belittling statistical models. What is at issue, is the fundamental nature of reality. Chaos can arise from order. But order cannot arise from chaos. Even though chaos-based, statistical, or monte carlo approaches are useful in learning about the world or even gaining control of the world, we must not loose track of the fact that the ground upon which all of these methodologies stand is purely deterministic, and that they merely give us generalizations of systems while doing nothing to elucidate the details of the inner function. The fundamental mechanisms that drive reality must by necessity be causal, if they are to give rise to our causal world. And causality is just another word for determinism.
<hr>
With regard to your "physical plea".
First of all I would like to point out that being a atheist I don't like order as a prerequisit for obtaining a universe. This reeks to much after a god concocting it all.
This is ridiculous. Why should order entail design? I think you are overgeneralizing based on your anthropomorphic perspective.
Second I claim that in a deterministic universe time doesn't really exist as such.
I concur, partially. The "continuum" of past-future-present is an illusion; there is only the present. However, change does occur, and therefore the universe is indeed evolving and not static. So, of course, there is still the "arrow" of time, however improperly we have tended to perceive it to date.
What is time ultimatly ? It is something that is very closely related with change however nothing really changes in a deterministic universe.
Here, you are playing on words. A non-interactive computer program is entirely deterministic, so that given its precise state at any moment, you can trace back to all of its past states, as well as predict all of its future states. Nevertheless, the computer program is still doing something, accomplishing some goal,and oftentimes, I'd say, it even has a purpose.
However time as in change is the basic dimension for our existence, if there is no change, there is no existence. The non existence never changes for there is nothing to change, everything that doesn't change (and I mean never as in through all time) doesn't really exist. So a deterministic universe doesn't exist !
The "existence" you refer to is from a perspective that is somehow external to our universe. From that point of view, the universe is indeed either just a static object, or a record playing itself out. Mind you, the object (or the record) still exists -- even though it does not interact with its external environment, whatever that environment may be (and even if such an environment exists.) So if the universe indeed lives in some larger world, but is completely closed off from that world, then you could say that to that external world the universe does not exist. For us, however, the perspective changes. Being part of the universe's state, we are directly involved and are part and parcel of state change across timeslices. To us, there is indeed change, and there is indeed existence.
If you think about it determinism take away everything that makes life worth living, it puts life on the same level as death. It puts existence on the same level as non existence and that is actually a contradiction.
What is it that makes life worth living in a nondeterministic universe vs. a deterministic universe, may I ask? And, there only are contradictions if you choose to define your terms in a contradictory fashion. Paradigm shifts usually involve novel use of language; you cannot use a nondeterminist vocabulary on determist issues and expect reasonable outcomes. But a challenge I'd like to fire back at you, is how can any type of ordered existence whatsoever be possible in a universe where there is no order at the most fundamental level.
Something else that strikes me in the believe that it would be possible to know everything is that this very much resembles the Icarus story. It is a longing to become God, to be able to obtain immortality and become detached from the universe itself.
In fact, as a determinist, I have successfully argued that it is impossible to know everything, even if you learn all the deterministic rules and all the state fundamentals of the universe's operation -- see the <A HREF="http://www.exosci.com/ubb/Forum8/HTML/000175.html">Contradictions</A> thread in teh Religious Debate forum. In fact, having complete knowledge of the mechanisms that drive reality does not constitute a complete knowledge of reality; a God's perspective would be to not only know all of the reality's mechanisms, but to also know the reality's complete state during some timeslice (which is what is impossible).
It is also a disturbing belief in the controllability of the universe or in society it is something that could serve very well as a bases philosophy for a totalitarian regime. This also has a very strict set of rules and tries to mold society in that way. The reason why these regimes never succeded is ultimatly because the universe is not governed by strict laws but it rather searches its own way.
This is even more ridiculous. There is nothing about determinism that dictates one social policy or the other; in fact, there is no mention of human societies at all, nor should there be. Determinism is about the fundamental nature of reality, not about how we should behave ourselves. And coming from a physicist, the statement that "the universe is not governed by strict laws" is baffling, to say the least. What seems to be the case in terms of humanity, is that humans are not idealized nor identical either in their individual structure or function. Therefore, they will never as a population completely comply with a rigid set of rules. That is why there has always been crime, and always will be. And in case you haven't noticed, capitalistic societies, which I assume you insinuate are successful, are also invariably governed by pretty rigid rules and laws.
In eastern philosophy nature is something that is not describable by laws but rather something that becomes by itself. I like this very much...
Which begs the following question: just how exactly is this process of "becoming by itself" accomplished? Which is where determinism comes in.
------------------
I am; therefore I think.
Boris, I don't think I will top the length of your message but then again, I think you hold the record on that ;)
And coming from a physicist, the statement that "the universe is not governed by strict laws" is baffling, to say the least.
Isn't it ? I like to think it is. :)
Let me take you into a secret. Did you know for example that the so called fundamental interaction 'constants' of all four basic interactions are no constants at all ? What happens actually is as two particles get closer and closer together, these so called constants change. Hence the search for some unifying force that emerges at the highest engergies or (equivalently) the smallest distances.
You most think of the current values of the 'constants' as some kind of settlement with the current avarage energy level of our universe. This means that even the fundamental forces are subject to evolution. Don't worry however there is still a nice formula that explains the change but it is a sign on the wall.
What I'm saying is that all those nice formulas we keep finding to explain everything might just be a temporary view on how the universe behaves in our observable region of space. This would mean that the universe itself actually evolves and adapts...
The fundamental mechanisms that drive reality must by necessity be causal, if they are to give rise to our causal world. And causality is just another word for determinism
I agree with the first part but not with the last. You see if reality is probabilistic at the fundamental level then nothing prevents causality to occur still. For something to have some chance to occur there still needs to be a reason but if something occurs it needen't exaclty follow there is a cause for it.
Causation is only a necessary constraint, but not a sufficient one as it is in mechanistic causation.
Take for example an unstable atomic nucleus, physically there is absolutly no difference between a nucleus who is about to decay or one who isn't. The nescessity for the decay is an instable nucleus but the actual emission of for example an alfa particle has no cause at all.
This is no defeat of our human endeavor to understand our universe, quite the contrary, it opens new ways that have been closed until now. It provides a new fresh way to look at the world.
Further more you seem to think of statistical information as inferior to knowledge of each and every particle of a gas for example.
I'm afraid you will never understand self organisation if you don't go to the statistical description of a dynamical system. You see if you take trajectory descriptions of lets say turbulence in a gas all you find is chaos, if on the other hand you take statistical descriptions you see the funadmental mechanisms how for exaple a vortex is formed and how it behaves. If you are after fundamental mechanisms, you will get nothing out of deterministic, time-symmetric equations.
Nothing but a more complex version of mixing gases. Still the same type of matter/energy, still complex inelastic reactions, still complex interactions with environment, but every one of those reactions and interactions are causal and therefore deterministic.
You see it is exactly this attitude that I resent but it is what determinism ultimatly leads to. A true determinist can't possible have any respect for life. What is even more he can't even have respect for the gasses and chemicals of which he himself is composed.
Mind you I'm not pleading for some kind of world spirit here but only for a certain acknowledgement of which we come from and are made from. You see 'liveless' matter most have on some basic level the same qualities that we have, and one of the most treasured of these qualities is choice.
This by the way is the reason why I prefer an indeterministic universe over a deterministic universe : Choice
There are two kinds of knowledge: applied, and theoretical. The former is more concerned with what is observed, and doesn't care as much about how the observations are brought about. The latter is concerned with the mechanisms that give rise to trajectories.
You know I find this pretty concerning if you claim that Observed knowledge is inferior to theoretical knowledge. Next thing you say is that we better stop doing those messy experiments at all and construct our own theoritical paradise as how the universe should be...
For me observation still has precedence over theory even though I am a theoretical physisist from education. We can think and ponder as much as we like what counts is what we observe.
O yes, one more thing. The reason why we can model the functions of our brain on a turing machine is because we are actually only modelling the statistics, these behave deterministic. As in according to some formula, again you are confusion what really happens with a model.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
[This message has been edited by Plato (edited May 10, 2000).]
Why does determinism lead to some form of god or creator ?
As I said in a deterministic universe, each timeslice holds all the information of all other timeslices. This means that the actual information content of the universe is a closed system and is static.
If we look at the big bang event this information needed to be there, but how can such information exist in a singularity ? Or if we go just before that (if we can speak of such a thing as before the big bang of course) how can this information be there in the nothing ?
Somehow at the big bang there must have been some kind of information transfer into the otherwise closed deterministic universe. This can only point to some kind of creator, I know the believers will like this argument but then they must realise there is no such thing as Free Will.
If however the big bang itself was some kind of self organising system, information was created along the way and is now still being created.
Hi Plato,
What I'm saying is that all those nice formulas we keep finding to explain everything might just be a temporary view on how the universe behaves in our observable region of space. This would mean that the universe itself actually evolves and adapts...
Constants that aren't constants, no problem. We just replace them by an adequate function c(t) and we have a deterministic behaviour again. The universe evolves ? So what ? If we study long enough then we could even find a good model (and I have to be careful not to contradict myself with that word) that predicts this adaptation.
Please note that I am not raising the question whether we (meaning the current and coming generations) will "discover" this magical formula; from my believe in a fundamentally deterministic view of the universe, I am convinced that one day we will.
The nescessity for the decay is an instable nucleus but the actual emission of for example an alfa particle has no cause at all.
From my personal point of view this tells me that the theory that cannot predict the exact time of emission is a flawed theory. To counter this argument (rather badly), why don't all the unstable nuclei emit their alpha-particles all at once ? This doesn't occur, and hence I am forced to conclude that there is some mechanism that determines why some nuclei emit them today and some will in 1000 years.
For something to have some chance to occur there still needs to be a reason but if something occurs it needen't exaclty follow there is a cause for it.
How can you still live with yourself ? If things happen without a cause, then you could disintegrate without any apparent reason into trillions of nuclei just when reading this message. If things happen without reason, then the whole mechanism of cause and effect is destroyed, and hence about 99% of all physics we know (which is rather heavily based on this particular assumption).
It provides a new fresh way to look at the world.
I totally agree on this one. A fresh new look might give us more answers and aid us in our way to comprehend the universe and in our efforts to describe it (deterministically). Without fresh new looks we'd still be in the 15th century kind of "technology".
You see it is exactly this attitude that I resent but it is what determinism ultimatly leads to. A true determinist can't possible have any respect for life. What is even more he can't even have respect for the gasses and chemicals of which he himself is composed.
I disagree. A determinist can have an even higher appreciation of life than an indeterminist can. The determinist will step back and have a look at the wonderful theory of everything he just wrote down, marvel at its beauty and say "the mechanism of life is magnificent".
Also, I have to agree with Boris when he says you use the paradigm of determinism to prove your point of indeterminism (as you know, everything about the big bang is fundamentally deducted from deterministic laws). But on the other hand, we can never ask you to deduce a bigbang model based on indeterminism ;).
As a sidenote I would like to add that, after attending a lecture by Prigogine, I also was in doubt of a completely deterministic universe. However, when I had some more thoughts on what he said, I was not satisfied by his answer: his conclusion was that because we simply cannot know all the equations of state of every elementary particle, there is non-lineair and chaotic behaviour. (This is a very rude summary of what I've understood from what he said - the man's english sounded more like german). Perhaps it's just because I am still a newbie in this world, but I still have to find a good argument that convinces me of indeterministic behaviour at a fundamental level.
And coming from a physicist, the statement that "the universe is not governed by strict laws" is baffling, to say the least.
Isn't it ? I like to think it is.
I must say I was as baffled as Boris was, but heck, what the h*ll do I know ? :).
Bye!
Crisp
--
"The best thing you can become in life is yourself" - M. Eyskens.
[This message has been edited by Crisp (edited May 10, 2000).]
Crisp,
calm down, sit, have a sigare :)
We have always been thought that there is a one to one relationship between cause and effect, that is way we can't help but conclude dat everything must be deterministic. There are other logics however that do not adhere this confined principle.
I know this constitutes a severe paradigm shift but a lot of the research in many different fields of science points in this new direction.
The struggle of people like Bohm to put some determinism into quantum mechanics is really almost desperate. I like to compare it with the epicicle theory of Archimedes to explain the retrograde motion of some of the planets.
You see ultimatly determinism and evolution are uncompatible, it is just crazy to propose that the ultimate rise and fall of the dinosaures was already predisposed from the moment that gravity split itself from the GUT force. You must understand that the baby universe simply could not contain that much information so where does it all come from ? The same problem you have with the development of a brain from a strand of DNA, there isn't enough information on the DNA to form something that complex as a brain, where does the information come from ?
What we need is a new kind of logic that encorporates deterministic behavior as a special case of a system from which all choises have been removed. This means that deterministic behavior is still possible but only under strict rules.
If things happen without reason, then the whole mechanism of cause and effect is destroyed, and hence about 99% of all physics we know (which is rather heavily based on this particular assumption).
Maybe I was a bit obsure on that, I'm not saying that things happen without a reason but I'm saying that the same reason can have different effects. Like in the case of an unstable nucleus, the same reason (namely being unstable) can have different effects (namely for one nucleas decay now, for the other decay over a 1000 years).
Quantum mechanically there is absolutely no difference between different unstable nuclea of for example C14(or any other particles of the same kind), they are interchangeble so we are really talking about the same reason resulting in different effects.
Also, I have to agree with Boris when he says you use the paradigm of determinism to prove your point of indeterminism (as you know, everything about the big bang is fundamentally deducted from deterministic laws). But on the other hand, we can never ask you to deduce a bigbang model based on indeterminism
You see this is dialectic thinking, however one doesn't exclude the other. I'm not making a case for complete indeterminism here, I'm more agruing for something like incomplete determinism of wich complete determinism is a special case, hence still valid under certain conditions.
I also think that how we think about the big bang will be severely changed once the new fysics that is rising has found his way into cosmology.
However I envy you Crisp that you could attend one of Prigogines lectures. If you know of an other lecture of his please let me know, may be I will come to.
(Dan kunnen we misschien elkaar eens in het echte leven ook leren kennen ;) )
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Plato,
I concur with Crisp that variability in constants or indeed even laws is irrelevant. What matters is that any such variability be systematic and be itself causal.
As to your allusion to probabilities being a fundamental property of reality, this is where our fundamental difference arises. We might as well debate nothing else, other than the issue of whether probability, or a mechanism, comes first.
You see if reality is probabilistic at the fundamental level then nothing prevents causality to occur still. For something to have some chance to occur there still needs to be a reason but if something occurs it needen't exaclty follow there is a cause for it.
So, suppose that reality is indeed fundamentally probabilistic. What does that entail? Well, I shouldn't be too far off to assume that it entails certain events have higher probability of occurrence than other. Now, the question becomes: why should some events be more probable than others? If you assume that probability is a fundamental building block, you cannot provide a satisfactory answer to such a question; in fact, the only answer you can come up with is "just because it is this way." Which is not too far from the kinds of answers you get from religious people when you inquire why God has this or the other attribute. From a fundamentally determinist perspective, I will be able to tell you precisely why the probabilities are the way they are (e.g. a fair die has 6 sides with 6 different numbers, so the probability of seeing each number on a random toss is 1/6 -- but notice that I had to know something about the die (or indeed have a concept of a die) to provide such a derivation.) Of course, to be able to take advantage of a fundamentally determinist model, you have to have the model first. It is not something we currently have, and personally I don't even like the best running candidate (the M theory) all that much (simply because it assumes too many primitive entities for my taste).
You could argue that there is really no difference between knowing why certain probabilities exist in a nondeterministic framework, versus knowing why the fundamental building block exists in a determinist framework. The difference is, determinism indeed aims to reduce everything to just one, simple, and self-referential building block. A probabilistic approach will merely result in gazillions of different probability distributions for different situations, and will not be able to reduce that complexity to something simple and beautiful. From an aesthetic standpoint, determinism is certainly more promising. And even supposing that either approach ultimately can give the same levels of control over reality, you still must concede that while probability density functions can be derived from a deterministic description of the system, a reverse derivation is mathematically undefined. Therefore, a deterministic formulation is fundamentally more powerful, as well as far more concise. Furthermore, it is potentially much more insightful, since you can derive new and unexpected probabilistic solutions from a deterministic description -- but if your starting point is probability itself, you can only describe what you have observed so far, and you cannot induce previously unseen phenomena.
Causation is only a necessary constraint, but not a sufficient one as it is in mechanistic causation.
Take for example an unstable atomic nucleus, physically there is absolutly no difference between a nucleus who is about to decay or one who isn't. The nescessity for the decay is an instable nucleus but the actual emission of for example an alfa particle has no cause at all.
You are making a circular argument. You are arguing that causality is not sufficient for mechanistic causation, based on the assumption that nothing actually causes an unstable nucleus to decay. In case you haven't noticed, not only is your argument circular, but it is a classical mistake. You assume a negative, and hence assume a passive role of waiting for someone to prove you wrong. Provided everyone agreed with you, 0 progress will be made. If, on the other hand, you assumed a positive, then you might be continuosly trying to come up with a model that indeed explains all the probabilities in a deterministic fashion. Should you or any of your co-workers eventually succeed, you will have on your hands a beautiful theory that not only completely explains all the bird's-eye observations of nondeterminists, but probably also makes lots of empirical predictions -- which make your theory testable. And yes indeed, testability -- we completely forgot about that crucial criterion, haven't we? The reason why determinists have had such difficult time formulating a theory of everything, is because their approach indeed leads to testable predictions -- and so far they have been unable to pass the tests. Another reason is that we still don't have a good idea of what reality actually looks like -- heck, we are still missing 90% of the stuff in this universe! But just because it's difficult, doesn't mean it's not worth it. In my view, a fallback on empirically-grounded mathematical models with empirically-determined constants is a bit of a copout in the ultimate quest for understanding. We certainly need empirical science in order to tell us what the world looks and acts like -- but such shallow understanding should not be our ultimate goal. What should be our ultimate goal is to understand <u>why</u> the world looks and acts like it does.
With respect to your decaying atome argument, let me make an analogy. We know that every year some 30,000 people die in car accidents in a certain country, with the overall probability of any person dying in an accident within one year being something like 1 in 10,000. Now, these people are actually otherwise immortal, so their only way to die is through a car accident. Given one such person, can you predict when they will die? Absolutely not, since the person does not carry such information within them; the best you can do is build a probability density function, and talk about likelihoods of a person dying within some time period (in fact, given a constant death rate, your model would be a decaying exponential.) Yet, whe the person does die, you know with certainty that they had a car accident (because they couldn't die through any other mechanism.) So indeed the event of their death was deterministic and strictly causal. But how come you couldn't predict it? Simple: to predict that event, you would have had to know the complete state of not just that one person, but of the entire environment of that person, which, depending on whether nonlocality is real, may be the entire universe. So there is your answer: even though the event itself is deterministic, there is no way of predicting it, because there is no way of knowing the precise state of the entire universe. My and Crisp's argument are that the same is true of decaying atoms, and indeed of any other random variable in the universe.
Further more you seem to think of statistical information as inferior to knowledge of each and every particle of a gas for example.
I'm afraid you will never understand self organisation if you don't go to the statistical description of a dynamical system.
We are after different levels of understanding here. First of all, I don't just "think" that there is more information, mathematically speaking, in a more detailed model -- <u>I know so</u>. And so do you. The problem with understanding, is that our cognitive resources are limited, and we cannot keep track in our heads of billions of individual entities each with hundreds of parameters all mutually interacting among themselves and with their immediate environment simultaneuously. This is why we need to compress information in order to get it into our heads. So sure, to understand the world at a cognitive level, we need to simplify and abstract away -- and there is nothing wrong with that. However, the type of understanding that I am talking about is not the kind that directly allows you to easily grasp all of the implications of a model. Rather, if you had sufficient computational resources at hand, the type of understanding I imply would allow you to carry out timestepped simulations of a complex dynamical system, and observe the results. If the simulation matches observations, then you know the fundamental model is correct. Also, starting with the fundamental model, you can indeed proceed to build up a framework of escalating generalizations, probabilistic or otherwise -- but this time, you are mathematically assured of never missing anything important, because at each step of abstraction you will be able to derive an exact measure of how much information about the system is lost in the process.
A true determinist can't possible have any respect for life. What is even more he can't even have respect for the gasses and chemicals of which he himself is composed.
This is a matter of your personal opinion. I still do not understand why you are so eager to prescribe such a detached attitude for me. In fact, I could construct a diametrically opposite stance based on determinism -- that the entirety of the universe is just as precious and just as wonderful as the tiny subset of it that we call life. Respect is a matter of personal attitude; it has nothing to do with knowledge of the universe's fundamental nature.
You see 'liveless' matter most have on some basic level the same qualities that we have, and one of the most treasured of these qualities is choice.
This by the way is the reason why I prefer an indeterministic universe over a deterministic universe : Choice
And do you remember why people used to prefer a Newtonian clockwork space over an Einsteinian spacetime continuum? As I recall, it was all about <u>absolute frame of reference</u>. Back then, people were so used to that notion, it was so natural to them, that they simply couldn't accept the suggestion that absolute references are only an illusion. You are facing a similar conundrum: you are refusing to accept the suggestion that choice is nothing but an illusion -- a suggestion I and many others are making. However, I have the upper hand in this debate, because at the very least on the human level, I understand that the cognitive machine is a deterministic state automaton. So at least with respect to <u>us</u>, I *know* that choice is an illusion. It may take you a while to see this, but science is squarely on my side this time around, and this time I am the expert.
You know I find this pretty concerning if you claim that Observed knowledge is inferior to theoretical knowledge. Next thing you say is that we better stop doing those messy experiments at all and construct our own theoritical paradise as how the universe should be...
You are misinterpreting my position. What I said, is that theoretical models carry more information than empirical models. Naturally, empirical models must come first, but theoretical models are the ultimate end-result. This is why in the end theory is always superior to practice when it comes to actually understanding what is happening, rather than merely memorizing a rather arbitrary observed association between inputs and outputs. In studying, there are two fundamental approaches: rote memorization, and deep understanding. With the former, you are stumped by novel situations and must possess a heck of a memory to perform well in classical situations. With the latter, you don't need as much memory to explicitly remember all the formulae and results; you can derive many of them based on your deeper understanding of the system; furthermore, you will be able to successfully tackle novel situations, because you understand not just how a system responds under classical conditions, but why.
O yes, one more thing. The reason why we can model the functions of our brain on a turing machine is because we are actually only modelling the statistics, these behave deterministic. As in according to some formula, again you are confusion what really happens with a model.
You are simply wrong. As computer power grows, the brain is increasingly modelled at synaptic and molecular levels. True, at those levels we still use statistical abstractions to describe ion transport or neurotransmitter degradation, but at the level of neural behavior, we have complete determinism. And it is only at that level that cognition occurs -- therefore, a cognitive machine is a Turing machine, regardless of the actual substrate (and I claim that all substrates are ultimately Turing-describable anyway, at least in principle.)
<hr>
<center><h3>As for your other posts:</h3></center>
<hr>
Somehow at the big bang there must have been some kind of information transfer into the otherwise closed deterministic universe.
Indeed, there was -- and the information content of the universe has been fixed ever since. That is why whenever information is concentrated in one place, it must be diluted elsewhere -- which is just another way to paraphrase the laws of conservation of energy and matter.
This can only point to some kind of creator, I know the believers will like this argument but then they must realise there is no such thing as Free Will.
If however the big bang itself was some kind of self organising system, information was created along the way and is now still being created.
No it does not point to a creator at all. It simply means that the universe emerged somehow -- and nobody knows how. Indeed, a determinist view gives absolutely no indication of where the observed universe came from. If, on the other hand, you assume a continuous influx of information into the universe since the Big Bang, then you are indeed implying a meddling Creator! Talk about getting it backwards...
You see ultimatly determinism and evolution are uncompatible, it is just crazy to propose that the ultimate rise and fall of the dinosaures was already predisposed from the moment that gravity split itself from the GUT force. You must understand that the baby universe simply could not contain that much information so where does it all come from ?
Plato, just because something sounds crazy to you doesn't mean that it cannot be true. If you want to really demonstrate that evolution and determinism are incompatible, you are going to have to construct a mathematical proof. Until then, all I can conclude is that you simply find determinism too incredible to accept -- in which case, you must be growing old.
Indeed, the claim is that the baby universe contained all of the same information that it contains now. It contained all the matter and energy, and all the spacetime, that it contains now -- didn't it? And units of matter/energy/spacetime are merely units of information.
The same problem you have with the development of a brain from a strand of DNA, there isn't enough information on the DNA to form something that complex as a brain, where does the information come from ?
The answer is easy: the information is contained both in the DNA and in the environment within which the brain develops. In fact, DNA is meaningless without an environment -- and a common mistake is to assume that all information needed to construct a human is contained in DNA.
Your problems with determinism result from the fact that in order to create an abstract representation of some entity, you decouple it from its environment. This is when you begin to have events that apparently had no cause inherent in your definition of the entity. Of course such events will have no cause, because you have removed the environment -- the source of cause itself, from the equation.
------------------
I am; therefore I think.
1. Interchangability of elementary particles. There is actually far less information that is lost in a statistical description of a gass then a statisticle description of a population in which each individual actually is unique. Molecules are not unique, they are all the same. The only thing that differs between two atoms in a gass are their impuls and position (assuming that the kinetic energy of the particles are low enough not to exite them to higher energy levels).
2. Influx of information at the beginning of the universe. What is this, we don't know where it came from ? Suddenly we don't want to know any more ? The famous urge to know everything has come to a full stop ? Besides you forget something : the baby universe couldn't possible contain all the information that it contains today because it was smaller. Yes, I know the only thing that has changed is simply there is more 'empty space' but this empty space has a direct impact on the matter/energy contained in it, it poses new boundary conditions. So actually the information content of the universe has been and is still increasing, this alone is enough to refute deterministic theories. Then I even haven't mentioned the vacuum fluctuations that pervade so called empty space, more and more influx of unknowns that disable your nice deterministic model !
3. What are the mecanisms that make probability distributions who are not flat ? Boundary conditions ! You seem to be unable to disattach probability from some kind of underlying mechanism (e.g. dice). Observe the hydrogen atom : the central proton provides a boundary condition for the bound electron, hence its probability to be found close to the proton is much higher then further away. Ok but now I'm predisposing a distinctly localised proton, give me some credit here, the boundary conditions for the proton are something like 100000 times smaller then the electron, thus giving me all the right to temporarily hold it to be a mathematical point for calculating electron orbitals.
4. Thinking that the brain is deterministic because cognition only arises at macroscopic levels is committing the same error as thinking you can predict the weather by measuring temperature and airpressure all over the world. This is true but only for a limited amount of time, long term predictions are as valid as wild guesses. I guess you are familiar with the butterfly effect ? This means that even tiny quantum variations can ultimatly lead to totally new behavior. So if at the basic level the universe is probabilistic, so is the brain ! I know that you know a lot about how the brain functions but ultimatly it is just an other non equilibrium system and thus behaves in the same way. Since a Turing machine is in total equilibrium at all times : you get as much information back as you put in, it can never become a means to make true intelligence, it will always be 'artificial'.
5. Why have the deterministic equations been so succesful up until now ? Because they have always described ideal situations for example two body interactions, they describe but a small sample of reality. They are correct but only under certain conditions, it is a logical error to assume that they are applicable in all situations.
6. About my circular argument, I didn't say that causality is not sufficient for mechanistic causation, I said it WAS sufficient for mechanistic causation but not for PROBABILISTIC causation. I do not assume a negative, I prove there is no fundamental mechanism at work by showing that it is impossible to observe this mechanism. You see even Bohm ultimatly admitted that his theory was never possible to prove, the so called hidden variables are doomed to stay hidden forever ! So why persist in believing in them ? It almost is like a religious conviction in the ultimate triumph of determinism. Besides the proof that the Einstein-Rosen-Podolsky paradox isn't really a paradox has been done in the eighties and clearly demonstrates the non-locality of quantum mechanics and if you say non-locality you say probability. Determinism is dead and buried but it doesn't want to admit it !
7. If you get the feeling that I'm prescribing some kind of detached attitude for you then this is totally not my intension. I was more talking about a determinist in general. Once you start marvelling about beauty you give up your deterministic views. You think there is something that devides personal attitude and fundamental nature of the universe ? How is that ? For a determinist marvelling about beauty is something he can't help but doing since this was compelled at the time the universe was conceived. ;)
8. A meddling god in a indeterministic universe would not be a true god in the christian sense since he wouldn't know what his meddling ultimatly would arise to. The universe is in constant need of meddling, no problem for an omnipotent god of course but this means that the system universe plus god is still deterministic unless you assume that the god doesn't know what he is going to do next. Besides an open universe doesn't need a god to make choices for it, it can do that for itself (thanks to Occam we dispose of the meddling god notion) while a deterministic universe does need this information input at its conception.
------------------
"If I have been able to see further, it was only because I stood on the shoulders of giants."
Isaac Newton
Hi Plato,
You see ultimatly determinism and evolution are uncompatible, it is just crazy to propose that the ultimate rise and fall of the dinosaures was already predisposed from the moment that gravity split itself from the GUT force. You must understand that the baby universe simply could not contain that much information so where does it all come from ? The same problem you have with the development of a brain from a strand of DNA, there isn't enough information on the DNA to form something that complex as a brain, where does the information come from ?
It depends on how you look at it ofcourse. What you call "all the information" is something I would prefer to call "initial conditions" for the deterministic super-equation. Then, by using these initial conditions, you can determine what will happen to each particle in the past, present and future. Sidenote: You will probably (and I mean this in a deterministic sense ;)) argue that in the babyuniverse there were no particles but only energy (and hence nothing to apply these initial conditions to), but I would like to refer to the "Energy = Matter = Fields" post in the General Astronomy forum, where I argue for a theory that describes everything as energy (and because of the equivalence with matter, particle initial conditions can also be applied to their equivalent amount of energy).
Now the problem you seem to have with this view is that the universe cannot be able to store all this "information" somewhere.
The way I look at it, this information doesn't need to be stored anywhere. Let's assume for an instant that time is discretized (e.g. into steps of 10^(-50) second). In your point of view, the universe then has to contain the following number of information:
(lifetime of universe)*(number of parameters)/(10^(-50))
The "number of parameters" refers to the number of ways a particle can interfer with other particles (eg. electromagnetic forces) and the number of coordinates needed to exactly pinpoint a particle in space (eg. 3 for place, 3 for rotation, 1 for time).
Ofcourse this is a huge amount of information to store.
But why should this information be stored anyway ? I'd like to look at it the following way: after every 10^(-50) second, the universe evaluates all particles, how they should interact with the other particles in the next 10^(-50)s slice of time, and let the particles act accordingly. This is the "we don't care for tommorow, let's care for the next 10^(-50)s" approach ;).
Okay, this discretization of time is a dangerous thing to say ofcourse, but I personally think that this would save us loads of trouble,eg.:
the problem of timetravel is solved when time is discretized: there is no past or future, only the present. Hence timetravel is impossible).
the problem of living matter is solved. Every interaction of a living being is evaluated at every instant.
But I still have to do some thinking on that, for example see what the effect of timedilatation does to this model.
I'm not saying that things happen without a reason but I'm saying that the same reason can have different effects. Like in the case of an unstable nucleus, the same reason (namely being unstable) can have different effects (namely for one nucleas decay now, for the other decay over a 1000 years).
Okay, to me this is a confirmation that quantummechanics fails at this point. "Why, but now when" is not a satisfactory answer.
In regard of your reply to Boris,
Besides you forget something : the baby universe couldn't possible contain all the information that it contains today because it was smaller. Yes, I know the only thing that has changed is simply there is more 'empty space' but this empty space has a direct impact on the matter/energy contained in it, it poses new boundary conditions. So actually the information content of the universe has been and is still increasing, this alone is enough to refute deterministic theories. Then I even haven't mentioned the vacuum fluctuations that pervade so called empty space, more and more influx of unknowns that disable your nice deterministic model !
Hrm, doesn't this violate the conservation of energy/matter rules that apply to any closed system, as information (and hence energy/matter) is introduced ? And how would you explain, from an "incomplete determinism" point of view where this new information comes from ?
About the virtual/real particle creation/annihilation in vacuum; those particles are formed from energy and energy can be described deterministically.
Why have the deterministic equations been so succesful up until now ? Because they have always described ideal situations for example two body interactions, they describe but a small sample of reality. They are correct but only under certain conditions, it is a logical error to assume that they are applicable in all situations.
Completely true, but it is, as you called it, a logical error to apply this model to larger systems. The deterministic equations we know, indeed only apply to a specified region of space (from femtometers to lightyears, ranging from theory to theory). I don't see how this can be a plea for indeterminism; Personally I'd say it's a plea for more research and a confirmation of our limited knowledge.
As a last note, I would like to concure with Boris when he talks about determinism in probability. The only reason we have probability is because we have a deterministic procedure to determine what all possible outcomes are of a proces. For example, take the Gaussian distribution: the only reason that this distribution yields results from -oo to +oo is because we know for sure that the particle (or anything else) can have this set of values. On the other hand, the Chi-Squared distribution only allows a region of |R (the real numbers). If we use this distribution, then suddenly determinism is introduced about the area of space the particle can be in, and to create the distribution, assumptions of determinism are used.
In schematic form: determinism -> probability -> determinism
This is not a convincing argument at the moment, but I'll work this out a bit further.
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
[This message has been edited by Crisp (edited May 13, 2000).]
I will try something new here, see if visualisation can help my cause. (I must be getting desperate ;) )
http://igw.tuwien.ac.at/igw/menschen/hofkirchner/papers/InfoScience/Emergence_Logic_Expl/image2.jpg
This represents complete determinism. It has been the fundament of science since Newton. However it needs revision :
http://igw.tuwien.ac.at/igw/menschen/hofkirchner/papers/InfoScience/Emergence_Logic_Expl/image3.jpg
would be the representation of incomplete determinism. According to this logic, the strangeness of quantummechanics makes perfect sense. You see it is just a question of using the correct logical frame, there is no magic or acts of god involved.
If you want to read more about this new form of logic or the philosophy that is behind it I refer you to Emergence Logic Explained (http://igw.tuwien.ac.at/igw/menschen/hofkirchner/papers/InfoScience/Emergence_Logic_Expl/echo.html)
Crisp, in response to your question of where does new information come from in an open universe, you only have to look at the second relationship. Once you let go of the strict relationship between cause and effect new information automatically emerges (hence emergence philosophy).
Besides I don't really think you grasp the implications of one to one cause and effect (my excuses if you do and I simply have misinterpreted your last post) Even though the universe might seem to live from moment to moment (which you can choose arbitrarily close together so actually as far as we are concerned is time a continuum and not discrete) every one of these moments holds all the informations of all moments to come and that have been. Boris will confirm this even though it might be the only thing he agrees with of my entire post :D :D
Something else entirely, how are the examens going for you two ? (just to keep things not as serieus all the time)
Hi Plato,
Thanks for the images, but they didn't tell me anything new (the images told me axactly what I understood from your posts).
Besides I don't really think you grasp the implications of one to one cause and effect (my excuses if you do and I simply have misinterpreted your last post)
I thought I did, but now you made me doubt ;).
Even though the universe might seem to live from moment to moment (which you can choose arbitrarily close together so actually as far as we are concerned is time a continuum and not discrete) every one of these moments holds all the informations of all moments to come and that have been.
Why should that be ? Ofcourse all the particles and other energy have to be contained (assuming the universe is a closed system and the conservation of energy is valid), but I don't see any reason why information about "old" positions of particles should be contained. To get back to the discretization of time point of view, the universe just "looks" where all the particles are (regardless of where they were in a previous slice of time) and "repositions" them according to some law we'd call a physical law.
Now, on the other hand, if the universe lives from moment to moment, how can there be a physical law that predicts something about the future when the information of the future is not contained in the universe...
Hrm... Better do some thinking on this.
Bye!
Crisp
There is a statement you made in Evolution vs. Creation that I want to address:
There is one thing that I agree with however and that I suspect Boris will defy ( :D) the whole is different then the parts. This brings me back to the determinism thread but if you assume a one to one relationship between cause and effect there is no difference between the whole and the parts, the whole carries as much information as the parts contain, however when there is a one to many relationship new information can be created and can lead to new properties of the whole.
Especially in light of your illustration, I fail to understand how you can make such a statement.
First of all, given a many-one mapping from cause to effect, you are in fact loosing information by only observing the whole -- which is in part what I've been trying to state in this thread. Think about it: given an effect in a many-one mapping, can you deduce the cause? Given a cause in a many-one mapping, can you deduce the effect? It's "no" in the first case, and "yes" in the second case, if there are any doubts. In the first case, you know only the effect. In the second case, you know both the effect and the cause. This means that in the second case we possess fundamentally more information than in the first case. Therefore, by only looking at the effects, or at the "whole" in the sense you use the word, you are in fact loosing information.
Yes indeed, the "whole" is different from the parts -- but only in the sense that it is an incomplete, lossy representation of what's truly going on. You could argue that the whole may possess some attribute that the parts do not, such as, for example, transparency -- but this would be a play on semantics. The attributes normally understood to belong to the "whole", are merely attributes of a collection of the parts. In the same way that three Newtonian orbiting bodies give rise to chaos (an "emergent" feature of a system of deterministic parts) -- so are all the other properties of composite objects driven by the collective behavior of those objects' deterministic constituents.
Secondly, I contest the entire idea that two distinct causes will have a precisely identical effect. If that were the case, then I do not see how the two causes can be defined as distinct in the first place. The very reason we consider causes to be distinct, is because they arise out of distinct interactions or types of interaction -- which implies that even if the <u>observed</u> effect is the same, internally the mechanisms are quite different, and the observations that we make describe only a part of the outcome. In essence, were we to indeed discover such an apparent many-one mapping, it would suggest to me that we are observing only part of the outcome, and failing to capture information that would have enabled us to distinguish the underlying causes from one another.
Now, back to this thread, and your itemized rebuttals... For the sake of keeping this post somewhat brief (yes, I know, brevity is seldom a virtue I exhibit :)) I'll just refer to your post by the same numbers you used, instead of quoting it directly.
1. It is irrelevant whether we are talking about people or subatomic particles. When you say that molecules are all the same, you cannot be more wrong than when you say that people are all the same. For, we all know that each molecule is composed of a large number of known elementary "particles", each of which possesses a slew of its own parameters. Moreover, because of that complexity at the level of the Standard Model, as a determinist I suggest that the "particles" we observe are also no less primitive than a molecule or perhaps indeed a human being; they may in turn consist of many other components of which we are unaware at present. The point is that all those components, besides having a unique identity unto themselves, also possess their own unique parameters; thus, even a simple molecule's parameter vector is quite long indeed. But that is not the real point; the real point is the difference between observing a deterministic outcome, and being able to determine it ahead of time. While the former happens all the time (any time we observe something), the latter is impossible in practice (because we cannot know an exact state of anything, due to the uncertainty principle.) We can, however, pretend to know all the parameters of a theoretical system, and proceed to simulate it in full detail; if the simulation outcomes match real world observations, we can judge our deterministic model to be correct. And in fact, if we are able to create special cases where the mapping from state to outcome is smooth, we might be able to determine an entire complex state of a system by matching its behavior to a simulated model with that initial state.
2. It would be nice to know where the universe came from, but regardless of your stance on determinism, you gain no information concerning that particular question. What I refer to as "information", is the complete set of all parameters of all elementary entities in the universe at any single instant in time. Because matter/energy/vacuum are not being created or destroyed, the total number of parameters in the universe remains constant. This is what I mean when I say that the information content of the universe is fixed. The parameters may be changing values due to mutual interactions, but such changes do not alter the total information content. Entropy may flow from one subset of parameters to another, but the sum total stays fixed. It is true that there is ever more "empty space" in the universe; however we do not yet understand where it is coming from. In M-theory, for example, the three spatial dimensions we observe are expanding at the cost of other dimensions contracting, so the sum total is still constant. The "vacuum fluctuations" are something I like to liken to waves on an ocean's surface -- though apparently random, they are still a deterministic result of motion and mutual interaction of countless molecules and ions that constitute the ocean's essense.
You seem to have some kind of an urge to oversimplify my "nice deterministic model" -- which allows you to subsequently balk at all the inconsistencies that come from such oversimplification. Inconsistencies only arise because you are focusing your attention upon a superficial description of reality, rather than trying to picture an entire underlying hidden universe seething with activity and complexity. Contrary to your apparent suggestion, determinism promises a universe far more complex, multilayered, hierarchical, and structured than any other possible approach. The difference between you and me, is that I want to resolve the individual trees where you only wish to see the forest. I enjoy the concept of a forest and I find it useful, but I also want to know about the trees, and the grass, and indeed the very cells and elementary particles from which the forest is composed.
3. Fine, let's obseve the hydrogen atom. Suppose, for argument's sake, that we have discovered the inner structure of the electron and indeed of the very field through which the electron is interacting with the photon. Now, we have the exact mechanism that gives the exact characteristics of the electron at any moment in time, provided we know its exact starting conditions. So, we calculate the state of the electron into the future, and discover that something in the fundamental mechanisms we discovered causes the electron to spend more timeslices closer to the proton than farther away. So now, we have the actual mechanism behind the probability distribution. In general, there is absolutely no way you can "disattach" a probability distribution from an underlying mechanism. Indeed, by its very nature a probability distribution is a low-moment, lossy description of some mechanism (and it is precisely because of the extreme lossiness of probability distributions as descriptions, that we cannot trivially derive a mechanism from a distribution.)
4. You are missing the point again. Take the weather example. If you knew absolutely all the parameters of the Earth's current atmosphere, you'll still be unable to predict weather into the future accurately -- but not because of some fundamental nondeterminacy in the system. The reason is that the system is not isolated -- it is receiving input both from the Earth's interior, and from the Sun, as well as from the infalling meteorites, and indeed from butterfly wings. You see, if we knew the complete state of an entire region of the univers within some light-radius of Earth, then we would indeed be able to predict the exact state of the atmosphere for up to the amount of time it takes light to traverse that radius (and thus provide unforseen input to the atmosphere). And actually, if quantum nonlocality is for real, we'd need to know the precise state of the entire universe to deterministically predict weather.
I am getting tired of repeating this over and over, but I'll keep repeating it until it sinks in: there is a difference between understanding how something works, and being able to completely describe something. The former is the goal of determinism. The latter is impossible -- not only for the weather or for the brain, but even for a single photon. The brain is indeed a Turing machine, but in real-world conditions its state is impossible to predict because it is constantly receiving input through its sensory apparati, as well as through interaction with the body that encases it. However, if we were able to computationally simulate a complete developed brain, and feed it controlled input, we will observe the same deterministic outcome every time we repeat the same exact experiment. In essense, with respect to the brain its immediate surroundings become part of the Turing machine -- part of its input on the tape. Without having knowledge of both the complete state of the brain and its current input, you will not be able to exactly predict the next state.
5. Equations are nice, but there are very few things in nature (aside from simple, idealized laboratory experiments) that can be described by nice tidy equations. The majority of natural systems to not offer clean analytical solutions. This is why many tasks in real-world engineering are tackled through computer simulation -- be it weather forecasts, plasma flow in an inertial confinement reactor, or virtual car crashes. However, what is crucial in such endeavors, is to know the fundamental interactions between the components of a system you are trying to simulate -- and yes, those fundamental interactions are deterministic and indeed described by nice tidy equations.
6. First of all, I do not see why we have to assume that we have reached a limit in our resolving power. There may be such a thing as Planck scale, but we still have a long way to go before our measurements can approach that degree of precision. And in the meantime, who knows what "hidden variables" will yet come out of hiding? Remember the time when protons and neutrons were assumed to be fundamental particles? Described by simple models, and everything worked nicely -- until we started using particle accelerators, and discovered quarks. Indeed, just when do you suppose we are going to finally hit that impervious wall beyond which we supposedly can no longer peer? Maybe Niels Bohr can give you some insight regarding what science of the future will and will not be able to do? And even then, when we become somehow ultimately and fundamentally limited by our instruments and can no longer hope to detect the "hidden variables" directly, we might be able to deduce their nature from what our instruments do allow us to observe. You see, when a tree falls it makes a sound, even if nobody is listening; and if we listen for it, we just might be able to tell that a tree fell without ever having a chance to directly observe it. It is precisely due to such possibilities (or, indeed, expectations) of future discovery that a determinist believes in "hidden variables"; to refuse to look deeper is to give up on any further progress that might have been made otherwise. And once again, nonlocality has nothing to do with determinism or lack thereof. It may carry significant implications for relativity (due to its faster-than-light interactions), as well as for the ultimate theory of everything -- but whatever mechanisms mediate nonlocal interactions must still in themselves be deterministic and indeed causal. Indeed, the EPR experiments have demonstrated, if anything, that nonlocal interactions still obey the laws of cause and effect -- only by altering one of the entangled particles do we also determine the state of the other.
7. Here, we are once again getting into discussion of meaning. Even though as a determinist I am convinced that both my attitudes toward things and your challenges to my attitudes have been predetermined from the beginning (whatever that "beginning" is), I would say that as a sentient entity, my own attitudes and actions still have meaning to me. It does not matter if I am only a tiny part in a larger machine; as a very special kind of part I have my own internal machinery (at least as long as I continue to exist as a "human being") -- and that machinery has its own internal states which construct a representation of meaningfulness and purpose.
8. Care to elaborate what you mean by "open universe"? Are you suggesting that the universe as we know it is not a closed system, and that information is coming into it from somewhere else? In which case, where from? Does such a construct give you fundamentally any more information about the universe than the assertion that all of the universe's information was already contained by it at the moment of the Big Bang? As to where the information came from, the question is exactly equivalent to asking where the universe came from, since in my book the universe and "information" are really one and the same thing.
Oh, and also, with regard to "choice" -- under your framework, just how is it that the universe makes its "choices"? Are you saying that there is no mechanism behind the "choice"? In which case, why is "choice" the correct word to use? (Wouldn't it be more accurate to call it "noise"?)
------------------
I am; therefore I think.
[This message has been edited by Boris (edited May 16, 2000).]
Adlerian
05-16-00, 05:40 PM
Boris: It was hard for me to follow all of what you said. A scientist outside his specialized field of knowledge is just another lay person. However, I did want to compliment you on what I DID understand (about 80% of what was said). YOU AREconsistent! There is nothing more that I admire more than consistency in thought. At some point it will be fun to talk about the Turing machine as you call it. I believe in the immateriality of the mind and another thread should yield some interesting posts between us. Speaking of which...tapping foot... I know you said you haven't as much time as you'd like to respond on the Evolution/Creation argument but I AM waiting. ;)
GOOD JOB!
Adlerian
Boris,
parts/whole:
I wasn't really talking about losing information but rather obtaining new, in the light of the illustration : you win some but also lose some hence you get new information ! This means that the parts can hold different information than the whole.
By this I can say that the whole isn't just a lossy representation of what is 'truly' going on but indeed something with new information !
By only observing the whole you can't deduce the workings of the parts and by only observing the parts you can't deduce the workings of the whole. This is the sad truth.
About the two distinct causes having the same effect:
To tell you the truth I was a bit at loss about that one either but then it occured to me that what was meant were processes like absorptions. Again like in emissions there is no quantummechanical difference between an atom that has just absorbed a photon with one that has done this 5 minutes ago. So two different absorbations (causes) can result to one and the same (identical) exited atom (effect). Your whole reasoning is simply based on complete determinism where the only way you can have distinct effects is when there are distinct causes, I'm telling you that this logic is not applicable to quantummechanics and chaos theory !
All is not lost however, we can still deduce causes from effects and effects from causes, we only have to be more careful. We have to restrict our observed systems like if we do measurements with particle accelerators we only observe a single collision at the time. These are transient interactions, they describe free - collide - free type interactions.
I will also try to follow my previous enumerations :
1. I'm afraid I'm not wrong, you see if we keep the energies low enough it doesn't matter how many elementary particles are involved in one molecule, if they are all in their ground state (meaning the internal energy of each molecule is at its minimum) there is no difference what so ever between the molecules. You see the only thing that matters is the wavefunction, or as Prigogine would argue the probability matrix, this is exactly the same for molecules (of the same kind of course).
I don't know if you have ever seen a diffraction diagram of protons in a two slit experiment ? You get exactly the same patterns as with a photon (light) while we know that protons are actually constituted out of quarks. This however has no effect on the diffraction pattern, it shows as if every proton is exactly the same (and it is I can't stress this enough).
2. I think you are confusing determinism with stringtheory here even though you must agree that stringtheory is as indeterministic as quantummechanics because it really is quantummechanics. You see String theory is not really a new theory in the sense that quantummechanics was in regards to classical mechanics or now the new probability mechanics that is emerging.
Everyone knows what is should do and if there are some more dimensions involved in doing this then so be it, they still need to be proven to exist !
What I don't know is if String theory also is time symmetric, I suspect it is however but I haven't checked it. Do you know, Boris ?
3. See 1. I should say, inner structure has no relevance at all ! You seem to think that there is something like a basic particle of which everything else is build and if we know the exact position and momentum we know everything there is to know.
This is not how it works, Boris ! You see the reason we know there are things like quarks is by bouncing other things at them, we have to do this at very high energies and it is only by virtue of these high energies that they become visible. If these energies are not there, the quarks are invisible again. And by invisible I mean not detectible, not for you, not for me, not for the electron that is bound in the hydrogen atom. If they are not detectible then they also have no effect on the system of the electron, this means as far as the electron is concerned : they aren't even there !
And Boris, if you think there is no way you can disattach a probability distribution form an underlying mechanism then you must still believe in ether ! You see, there is also no underlying mechanism for photon waves to propagate in ! You are missing the point entirely if you can't see this I'm afraid.
Here I must come to an end with my responses but I promise I will continue as soon as I have time again.
------------------
I err, therefore I exist !
Epitectus
05-17-00, 02:15 PM
You need to consider gyromagnetic ratio's to see the effect -t and t has on Hiesenburgs uncertainty principle. The angular momentum of an atom, as well as its orbit are indetermistic, becuse u don't know where the atom is at any given time. The atom may be travelling faster than the speed of light, and is affectede by gravity, the rotation of the earth might have to be considered.
Epitectus
05-17-00, 03:07 PM
A wavelength vacuum
Epitectus,
nice idea about gyromegnetic ratio's but I don't see how this has anything to do with first of all Heisenberg's uncertainty principle or with timesymmetry. Could you please elaborate a bit ?
Boris,
Let me continue where I left of...
4. Granted the Earth atmosphere is not an entirely closed system but if we are looking at the universe as a whole I like to think that this is a closed system.
Now if you are claiming that it is the goal of determinism to understand how something works that it has failed to do that. Because it can't explain how the second law of thermodynamics works and it also can't explain how self organisation works.
Before you begin again about inertia as the explanation for the second law, let me tell you it has nothing to do with it. You see given an infinite amount of time every single state of the universe in a deterministic system must repeat itself (ultimatly the deterministic equations are periodical even if this period might be infinitly long in a non-linear equation for example), this blantly contradicts the second law which clearly states that entropy increases now and also an infinite amount of time from now.
Now, let's also stop pretending that we will one day succeed in measuring exact states of things. It is clear that you have never made a physical experiment, there is always noise. You can't get out of it, we are surrounded by it, we are constituted of it : precise measurement is impossible, now and always. It is simply the nature of the beast. You must understand that if it is impossible for us, it is also impossible for a molecule to know exactly where the other molecules are (be knowing I mean here simply interacting) or for the electron. If this is the case then we might as well accept that presupposing a distinctly localised electron is also rubbish and wishful thinking. The electron is not a particle nor is it a wave, it is a probability distribution. There is no mechanism underneath this destribution, there is only interaction with other distributions (e.g. electrons or other particles).
5. Boris, what these computers are calculating is a possible car crash or a possible weather system, this doesn't mean that they are capturing an actual event or predicting how it will actually happen.
The only thing that deterministic equations can do is show things that have been given in the first place. I say this again, a Turing machine can only give back information that is put in, there is a linear correlation between input and output. It can't anticipate, it can't invent, it can never be original ! In contrary that you and I who can do this.
The magic is done in the noise ! If you remember something, it won't ever be exactly the same as it happened, there is noise. Due to this noise you must guess and extrapolate, this automatically leads to a different kind of output which is not entirly based on what has been given as input. Noise has always been called error, as something bad but actualy it is the source of our freedom, freedom of determinism. That is why I changed my sign cause I believe that a deterministic way of existing isn't really existing at all :
I err, thus I exist !
6. We haven't really reached a limit in our resolving power as long as we keep in mind what we are talking about here. You see it might very well be possible to probe deeper and deeper into matter and keep finding smaller and smaller particles. But you must realise that if you are looking at a particle at distances of femtometers, you are sacrifising your knowlegde about it's impuls.
Actually there is good reason to think that quarks and certainly electrons are without any internal structure. Take for example the electron : it has a rest mass of 511 KeV and we know (by experiment) that it behaves as a point mass to distances <= 10^-17 m. If there is something that is smaller then this then the electromagnetic energy involved in producing this already exeeds many times its rest mass. This is of course impossible, same reasoning goes for the quarks. So the three families of elementary particles really does constitute everything there is (ignoring the force particles or course)
7. Boris, the machine doesn't 'construct' anything, everything is already there you as a part might have a meaning for the machine but the machine has none what so ever because it doens't do anything it just exists. Now, I don't call this existing because really the nothing also doesn't do anything so there is no difference between the nothing and the being of a deterministic machine.
8. An open universe is something that does something, where there is noise that brings in new things, that distorts old things and that makes evolution and life possible. An open universe gives people a choice and makes them responsible for it. There is no responsiblity in a deterministic universe cause there is always something that compelled you to the deeds that you did.
I'm glad that you in your last word came to the right conclusion : yes, choice for the universe is what we perceive as noise. It actually only becomes a choice if the actor that makes it has knowledge of the possiblities that are open. This knowledge is something that requires a fairly develloped cognition that we have only seen in multicelled organisms. Responsibility of this choice comes when the actor also has a sense of what his choises can cause, this requires some form of consciousness which perhaps manifests itself in the higher primates and maybe the whale families but it certainly does so in humans !
------------------
I err, therefore I exist !
Adlerian
05-18-00, 06:25 PM
Plato: This caught my eye.
I'm glad that you in your last word came to the right conclusion : yes, choice for the universe is what we perceive as noise. It actually only becomes a choice if the actor that makes it has knowledge of the possiblities that are open. This knowledge is something that requires a fairly develloped cognition that we have only seen in multicelled organisms. Responsibility of this choice comes when the actor also has a sense of what his choises can cause, this requires some form of consciousness which perhaps manifests itself in the higher primates and maybe the whale families but it certainly does so in humans !
I thought that Boris was referring to the human mind as a Turing Machine. Unless new developments have gone un-noticed by me there isn't a Turing Machine that has been constructed that can pass the test. Is there?
Actually, it is only humans that are able to conceptualize during cognition. Higher primates and mammals are conceptually blind, they are able to perceive but not conceive. This requires very precise use of language here so I should stop. But I will be creating a thread that concerns the immateriality of the human intellect and why we are different from other animals concerning our ability to think. It is a radical difference, not just one of degree, but I will leave that distinction for the thread.
Good post!!! :)
Adlerian
Hi Plato,
Now, let's also stop pretending that we will one day succeed in measuring exact states of things. It is clear that you have never made a physical experiment, there is always noise. You can't get out of it, we are surrounded by it, we are constituted of it : precise measurement is impossible, now and always. It is simply the nature of the beast.
We know! ;). But it's not the actual measurements we're talking about, it's about the fundamental (and let me stress that) kind of relation that exists and "predicts" the behaviour of particles. The fact that we measure nothing but noise at a certain point, is irrelevant.
Don't take this the wrong way, but I have the feeling that you are not looking "deep" enough. Yes, Boris and I - though I'll leave it to Boris to acknwledge this - agree that we SEE chaotic behaviour, yes there are probability distributions and yes, there are equations that have different outcomes if you put the same initial conditions in them. But this is still not fundamental enough.
The question is whether the underlying mechanism that determines what the particle does is deterministic or indeterministic (or incomplete indeterministic, whatever you want to call it). The question is not: "are we able to see or measure that the particle behaves deterministic or indeterministic" but rather "is the behaviour of the particle det. or indet.". (Sorry I repeat this 10 times, but the amount of "fundamentability" has to be stressed ;)).
The problem is ofcourse that we don't have an answer to that question at this time. We have some very neat theories (eg. QM) that pretty much tell us everything to the detail. But these are only theories where the kind of behaviour of every single particle is postulated. The probabilistic behaviour of particles is postulated and the uncertainty principle is a direct consequence of the postulates of quantum mechanics. This doesn't mean the interactions are indeterministic, because we simply don't know that.
Now I don't have the intention to reduce this debate to a philosphical argument with no right outcome (read: we want more scientific facts ;)), but you should have known this discussion would lead nowhere :).
Anyway, I'll get back on this in the weekend. I have early classes tomorrow and I should better spend my time sleeping instead of trying to tear apart the future of the discipline I am studying :)
Bye!
Crisp
Plato,
I apologize for the late response, but how should I have known that a poster I applied for at a research conference would be declined, and instead I would be saddled with both a talk and a paper! I've just spent the worst two sleepless weeks of my life in the lab, though I must say I accomplished more work in two weeks than I normally do in two months :) But now that I'm done with my 14-hour stint at the bed (man, that felt good...) -- I thought I'd get back to what really matters :D
By only observing the whole you can't deduce the workings of the parts and by only observing the parts you can't deduce the workings of the whole.
I must say I disagree with both statements. Indeed, what do you define as a "part" versus the "whole"? The reality as it enters our senses is basically monolithic; the segmentation of it into objects, actions and actors is entirely a cognitive phenomenon. Indeed, all we ever observe is the whole, and yet we are keenly aware of the "parts". Conversely, provided there are no nonlocal effects involved, you can indeed deduce the workings of the whole from a sufficient knowledge of the parts. That's, for example, how code breakers break encryption. That's how reverse engineers re-create a product that someone else designed and built. That is indeed how we have been reverse engineering nature up to now, and I don't expect that process to stop any time soon.
Again like in emissions there is no quantummechanical difference between an atom that has just absorbed a photon with one that has done this 5 minutes ago. So two different absorbations (causes) can result to one and the same (identical) exited atom (effect). Your whole reasoning is simply based on complete determinism where the only way you can have distinct effects is when there are distinct causes, I'm telling you that this logic is not applicable to quantummechanics and chaos theory !
Well, for one we both agree that the principles of quantum mechanics are inadequate as the ultimate substrate of reality. So I don't see any point in using quantum mechanics, which is obviously not a complete theory, to argue that something can or cannot be the case -- at least when that something is altogether out of quantum-mechanical realm of discourse. You say that the two atoms are identical. I say they are only as identical as two "identical" cars. They may look and feel the same to the user, but they are indeed distinct, and possess quite distinct internal states.
<hr>
And now, onward to our beloved enumerations :)
1) Ground state or not, you ought to agree that unless the entities in question are entangled, they are indeed distinct (i.e. if we measure their exact properties, we will get distinct instantaneous results, even if the overall distributions of outcomes are identical.) Another way to put it, is to consider the wave function versus where it comes from. You assume the wave function is the fundamental entity; I claim that it is a probability distribution generated by as-yet hidden mechanisms. And the reason we get different instantaneous measurements from the two distinct quantum entities, is because their respective generators of the wave function are in distinct instantaneous states.
2) Naturally, string theory is time symmetric. It is based on vibrations of membranes, and any oscillation is completely time-reversible by definition. Besides, how else would we get conservation of matter and energy?
3) There is a problem with your definition of "detectable". Is it truly necessary to <u>directly</u> perceive something in order to know that it exists? I should think it is quite often sufficient, even in accelerator experiments, to observe <u>indirect</u> effects of an entity to verify the theory that describes that entity. For example, would you find it just as easy to dismiss determinism if there appeared a deterministic theory that precisely predicted a whole bunch of empirically established "fundamental" constants, such as speed of light, vacuum permittivity, gravitational, etc?
And Boris, if you think there is no way you can disattach a probability distribution form an underlying mechanism then you must still believe in ether ! You see, there is also no underlying mechanism for photon waves to propagate in ! You are missing the point entirely if you can't see this I'm afraid.
Well yes indeed, I do believe there is something like an ether. Not in its classical connotation, mind you -- but you must remember that I've argued its case from the beginning; at one point I was calling it the cosmic Matrix. I indeed think that there must be something to propagate waves, in order for waves to even exist. There must be something to guide waves. There must be something to contain and define fields. There must be something that GR describes with manifolds. There must be something that gives rise to the various constants we associate with the "vacuum". I do not believe in "empty space" -- I see space as the fundamental layer (if not the fundamental substrate) on top of which everything is built. I believe that science is astoundingly ignorant when it comes to the most fundamental block of reality -- no small surprise, considering that even in this, the "advanced" age, we are still missing 90% of all <u>matter</u> in the universe, not to mention the fundamental "stuff" that gives rise to matter/energy/spacetime. You, on the other hand, seem to be under some kind of an illusion that we are close to having completely detected everything there ever was to detect. With respect to such attitudes, I said before and I'll say again: been there, done that.
4) Your objections here expose the lack of thought you, as a physicist, should have given to such issues. But let me, the amateur, enlighten you.
You see given an infinite amount of time every single state of the universe in a deterministic system must repeat itself (ultimatly the deterministic equations are periodical even if this period might be infinitly long in a non-linear equation for example), this blantly contradicts the second law which clearly states that entropy increases now and also an infinite amount of time from now.
This is not at all the case. Consider the following Turing machine:
<pre>
start: print "hello, world!", go to loop
loop: print "I'm stuck!", go to loop
junk: print "that's not possible!"
</pre>
Obviously, the machine has only three possible states. Obviously, the machine never halts. Obviously, the machine repeats its "start" state only once, no matter how long you wait. Obviosly, the machine never even enters one of its states -- ever. What's going on here? Isn't the machine deterministic? You betcha -- and the resolution to the paradox is.....that it is NOT a requirement for a deterministic system to exhaust all of its possible states, even given an infinite amount of time. In fact, it would be an amazing, next to impossible, freak occurrence if a Turing machine with as complex a state as the Universe, naturally arose with such a structure that it was doomed to not only go through all of its possible states, but also to continue repeating all of them as time passed!
The second law merely argues that the universe is constrained to shift state only in direction of increased entropy. This does not mean that entropy is going to increase at the same rate forever (which seems to be your assumption) -- this would imply a truly infinite amount of matter/energy in the universe (since "entropy" represents the amount of disarray in matter/energy), while we know that the amount is finite. What is happening, is an exponential drop-off in growth of entropy as the universe ages. As time passes and entropy increases ever slower, the total number of possible states that the universe can transition toward based on its current state, shrinks. In the infinite time limit, the universe will reach the state or the set of states with the lowest possible entropy -- and from then on, it will just cycle within that state or set of states, forever.
You can't get out of it, we are surrounded by it, we are constituted of it : precise measurement is impossible, now and always.
No contest to that. Your problem is not with the above statement; it is with the assumption that knowledge = existence. The assumption is clearly ridiculous. When a tree falls in the forest, it still makes a sound -- even if there is nobody there to listen. Though it may be physically impossible for any being or entity to <u>measure</u> anything to infinite precision, it does not follow that there is no true, absolute, intrinsicly correct value that we are failing to measure without error. Ever heard of the term "non sequitur"?
5) Forgive me, but once again I'm forced to quote:
Boris, what these computers are calculating is a possible car crash or a possible weather system, this doesn't mean that they are capturing an actual event or predicting how it will actually happen.
The only thing that deterministic equations can do is show things that have been given in the first place.
I have said it time and again by now, and please, PLEASE try to pay attention this time, and think it through:
<u>It is not the ultimate goal of determinism to predict actual events. It is often impossible to predict actual events, because such predictions require precise knowledge of a complete state of the system. What is the ultimate goal of determinism, is to understand the mechamisms that drive actual events.</u>
Naturally, if you have a deterministic description, and you provide it with a set of input parameters, it is going to produce a concrete outcome -- and that outcome will be merely a transformation of the input, or what "has been given in the first place". You are absolutely correct. In fact, given deterministic descriptions, it is often possible to retrospectively determine the original state of the system by merely observing the final outcome and putting the model in reverse -- which is a big plus for determinism. Whenever such feats are not possible, it is not because determinism fails -- it is because we fail to obtain a complete and exact description of the final state, not to mention that in certain situations (such as quantum mechanics) we don't even have any deterministic model in the first place.
Turing machine can only give back information that is put in, there is a linear correlation between input and output. It can't anticipate, it can't invent, it can never be original ! In contrary that you and I who can do this. The magic is done in the noise !
Not at all. First of all, what is this nonsense about linear correlation between input and output??? Turing machines are not mere finite state automata, they possess memory. But even finite state automata are perfectly capable of computing nonlinear functions, as well as non-analytical functions.
A Turing machine that is complex enough, and that has a sufficiently rich input, is capable of everything you and I are capable of (which is why we are indeed Turing machines, as is everything else in the universe, as is the universe itself.) You are forgetting that you are getting constant real-world input through all of your senses, and not just through your senses, but through any and all interactions of your body with the environment, down to absorption and emission of photons. There are a lot of things happening with the brain that make its behavior "unpredictable" -- but such randomness is merely an apparent randomness that is due to our failure to know all of the input factors that affect the brain's state. If we were to build a cybernetic equivalent of a human being, the "noisy" component of the biological brain that comes from its internal chemical and thermal interactions, can be simulated with similarly "noisy" artificial elements, such as, for example, very low-power electronic circuits -- and as far as the sensory input goes, we wouldn't have to simulate that at all, we could just equip the android with all the same senses that we possess.
Though I must say that at this time it is not even clear that the noise is a beneficial thing for cognition. In fact, it is apparent that the brain has evolved to ignore noise. Cognitive computation is done by entire pools of neurons, which, despite being individually noisy, aggregate their activity into a nice and smooth output. So I wouldn't be surprised if it was perfectly sufficient to have a completely deterministic machine in order to completely replicate human cognitive function. But either way, intelligent machines are coming -- perhaps even within our lifetimes.
If you remember something, it won't ever be exactly the same as it happened, there is noise.
Overly simplistic. One source of memory degradation is imperfect encoding (remember that discussion about compression and lossy representations?) Another is imperfect retrieval. A third is interference from other memories. A fourth is interference from other cognitive processes. A fifth might indeed be "noise" -- but any noise is ultimately deterministic anyway.
Due to this noise you must guess and extrapolate, this automatically leads to a different kind of output which is not entirly based on what has been given as input.
No sir, extrapolation (or generalization) has nothing to do with noise. It has everything to do with determinism. Our brains evolved to assume that the environment is predictable (and so it is); because of this, generalization from past experience is normal cognitive function, and deterministic indeed. Even single-layer linear perceptron units can do it (and nothing is more deterministic than that.)
Noise has always been called error, as something bad but actualy it is the source of our freedom, freedom of determinism.
Noise is not the source of freedom, neither should it be equated to error. It is simply the fact of life that nature is "noisy" from the point of view of a cognitive observer -- and hence all cognitive systems have evolved to deal with this noise. True, old-school AI approaches with their flowchart algorithms cannot deal with noise -- and that's why they are dead. The new school teaches us that cognitive systems are statistical processors. Ultimately, however, that does not matter -- computers can do statistics just as well as they can play chess.
6) Measurement resolution is not the ultimate issue here. The ultimate issue here are the very numbers that we get from our measurements. Why is it exactly that an electron weighs 511 KeV? Why is it not 512, not 510, not 5, not 1000?
If there is something that is smaller then this then the electromagnetic energy involved in producing this already exeeds many times its rest mass. This is of course impossible, same reasoning goes for the quarks. So the three families of elementary particles really does constitute everything there is (ignoring the force particles or course)
This is like saying that a brick house can be built out of bricks, but a brick cannot be built out of bricks -- therefore the brick is the fundamental unit. Should I remind you that our quantum-mechanical concepts are not the ultimate level of description?
7)
Boris, the machine doesn't 'construct' anything, everything is already there you as a part might have a meaning for the machine but the machine has none what so ever because it doens't do anything it just exists.
That's a pretty strong assumption, don't you think? What do you know of the machine's true nature, its true origin, its actual context?
8)
There is no responsiblity in a deterministic universe cause there is always something that compelled you to the deeds that you did.
That's a self-contradictory statement -- because responsibility is certainly one of the factors that compels you in anything you do. Even if your behavior is deterministic, responsibility plays a role in it -- and therefore it is also part of the machine (indeed, the very concept was generated within the machine in the first place!), and it is not meaningless.
yes, choice for the universe is what we perceive as noise. It actually only becomes a choice if the actor that makes it has knowledge of the possiblities that are open.
Again, you are assuming that noise matters at the cognitive level. Take your computer: it doesn't care about the noise in its circuits; the noise is sub-threshold and does not affect the computer's functions. Same is likely for the brain. The quantum noise is irrelevant, because the brain operates at a cellular level (if not at cellular aggregate level) -- many (dozens!) orders of magnitude above the noise.
It is an illusion to think that your behavior is not predictable in an absolute sense. You do not possess perfect introspection; indeed such a faculty has never been necessitated by nature. Therefore, you have only an astonishingly, overwhelmingly shallow understanding of what goes on in your head and how exactly you arrive at your conclusions and make your choices. No two brains are exactly alike, so it gives you an illusion that the choices others make or that conclusions others form are not predictable based on what you think you personally would have chosen or concluded.
Your position is that of a blind man who thinks he sees everything. I'm a blind man also, but at least I accept my blindness. What we perceive of the world is but a shallow silhouette of what's truly there -- difficult as it may be to accept such a fact based on our everyday experience.
------------------
I am; therefore I think.
[This message has been edited by Boris (edited May 28, 2000).]
Boris,
welcome back ! Let me treat you on a nice non deterministic dish ;)
but how should I have known that a poster I applied for at a research conference would be declined, and instead I would be saddled with both a talk and a paper!
I didn't know you were actually a PhD student, I thought you were younger then that. However it does explain your erudite a lot better I must say ;)
What was the paper and talk about if I might ask ?
Any way back to our discussion.
You know Boris, this thing you have with determinism really strikes me more and more as some irrational belief. I have collected here some of your quotes of your previous message :
You say that the two atoms are identical. I say they are only as identical as two "identical" cars. They may look and feel the same to the user, but they are indeed distinct, and possess quite distinct internal states.
You assume the wave function is the fundamental entity; I claim that it is a probability distribution generated by as-yet hidden mechanisms. And the reason we get different instantaneous measurements from the two distinct quantum entities, is because their respective generators of the wave function are in distinct instantaneous states.
There must be something that gives rise to the various constants we associate with the "vacuum". I do not believe in "empty space" -- I see space as the fundamental layer (if not the fundamental substrate) on top of which everything is built. I believe that science is astoundingly ignorant when it comes to the most fundamental block of reality -- no small surprise, considering that even in this, the "advanced" age, we are still missing 90% of all matter in the universe, not to mention the fundamental "stuff" that gives rise to matter/energy/space-time. You, on the other hand, seem to be under some kind of an illusion that we are close to having completely detected everything there ever was to detect.
Though it may be physically impossible for any being or entity to measure anything to infinite precision, it does not follow that there is no true, absolute, intrinsicly correct value that we are failing to measure without error. Ever heard of the term "non sequitur"?
A fifth might indeed be "noise" -- but any noise is ultimately deterministic anyway.
Even if your behaviour is deterministic, responsibility plays a role in it -- and therefore it is also part of the machine (indeed, the very concept was generated within the machine in the first place!), and it is not meaningless.
Again, you are assuming that noise matters at the cognitive level. Take your computer: it doesn't care about the noise in its circuits; the noise is sub-threshold and does not affect the computer's functions. Same is likely for the brain.
Your position is that of a blind man who thinks he sees everything. I'm a blind man also, but at least I accept my blindness. What we perceive of the world is but a shallow silhouette of what's truly there -- difficult as it may be to accept such a fact based on our everyday experience.
Take for example time symmetry. We know it is indeed the symmetrie that gives rise to conservation of energy. This however is a theoretical fact. On the other hand we have emperical data of the decay of K mesons were it shows that time symmetry is broken ! When I see this then I don't care what theoretical sacrifices we have to make but out goes the time symmetry !
You know up until today theorist have so far ignored this fact that has been known since the sixties. It has been dismissed as a freak feature that could be solved with a small patch to the otherwise time symmetric hamiltonian. After all the effect is terribly small, much smaller then the parity breaking.
In the field of thermodynamics, same story. It was always felt that thermodynamics was the study of equilibrium. Irreversible interactions were said to be due to incomplete knowledge of the real values of the observables of the particles.
This precidence of theory over emperical fact finds his origin with Plato and his freakin cave analogy. I can't say there is anything in the history of philosophy that I hate more then this cave analogy, with the possible exeption of the Ubermensch theory of Nietsche. Plato's cave metaphore spread like a disease.
Now, don't make the mistake that I want to replace the dominance of theory with a dominance of observation. I'm pleading for a symbiotic exchange of information. I always thought that this was science was really about...
I think it is only fair that I took his name as alias to put his mistake right again, don't you think so ? ;)
------------------
I err, therefore I exist !
[This message has been edited by Plato (edited May 29, 2000).]
Plato,
Well, actually I'm not a graduate student (yet) -- what happened, is that an undergraduate research project spun out into something that actually was of sufficient interest to people. I developed a system for discovering and tracking faces within a video stream in real time. It's actually not exactly what I want to do in the future (my goal is to do research in neural computation); it was just a tool I was developing for use by other people in the lab. It does combine a number of techniques in computational cognitive science, which is why I suppose it was of sufficient interest at the conference.
Anyway...
...this thing you have with determinism really strikes me more and more as some irrational belief.
No biggie. That particular assessment has been around at least since the Bohr-Einstein debates, and probably a lot longer. It is certainly a belief, but I don't consider it irrational. If anything, it's rational -- because it is a belief in the ultimate triumph of rationality. If you think about the entire scientific enterprise to date, you will notice an interesting trend: no barrier to knowledge has ever proved insurmountable. And barriers have existed before. In anscient Greece, the idea of atoms was ridiculed precisely because they were considered too small to ever be detected. Yet, we have found ways of detecting atoms without actually toching or feeling them with our senses -- we observe atoms by their indirect manifestations upon our instruments, by the way our predictions based on atomic theory are borne out in experiments. At this point in time, we are faced with a situation similar to that in anscient Greece. There are thinkers who propose that we have hit an insurmountable wall, and that we must abandon all search for concreteness and instead ground our understanding in abstract and meaningless mathematical constructs that seem to work. Then there are those of us who are not content with abstraction, who insist that behind every metaphor there must hide an actual referrent.
Mathematics has arisen out of attempts to systematically manipulate symbolic representations of actual concrete entities. Even when mathematics branched out into new and abstract fields, the rules of manipulation in those fields were designed to be consistent with the concrete origins of math. Now, mathematics has become a runaway process, enabling us to derive symbolic models of empirical phenomena, while having lost track of what the symbols are actually referring to. It is my belief, irrational though you may call it, that even in all of its abstraction modern mathematical physics still describes real objects, even if it has lost track of that fact. I have no problem with a probabilistic treatment of phenomena that cannot be measured precisely -- just as long as it is understood that the statistics is there to compensate for the shortcomings of the observer, not to be the fundamental mechanism behind the observed event.
But seriously, how else to address the following questions if not through determinism:
1) We want to know why empirical constants have the particular values they do
2) We want to know why the universe is the way it is: why there are two electrical charges and why the opposite charges attract and same charges repulse, why induced magnetic fields follow the right hand rule, why space is 3-dimensional, how matter/energy is connected to space/time, why matter and antimatter annihilate, what is inertia, how a photon's polarization plane accomplishes rotation, and so on, and so forth
3) We want to know what is the true nature of reality
If we ever want to find answers to such questions, we are going to have to concern ourselves not with just models that replicate observables, but with the very mechanisms that give rise to the observables. In other words, it is not enough to replicate or describe -- what we truly want, is to explain. Hence, ultimately, a determinist theory of everything is the Holy Grail toward which all science strives.
Take for example time symmetry. We know it is indeed the symmetrie that gives rise to conservation of energy. This however is a theoretical fact. On the other hand we have emperical data of the decay of K mesons were it shows that time symmetry is broken ! When I see this then I don't care what theoretical sacrifices we have to make but out goes the time symmetry !
This is news to me; I only knew of K mesons' fame in the CP violation arena. Perhaps there's a reference you've been tucking away?
I can't say there is anything in the history of philosophy that I hate more then this cave analogy, with the possible exeption of the Ubermensch theory of Nietsche. Plato's cave metaphore spread like a disease.
There, there, Plato. Now who's being irrational? :D
I think it is only fair that I took his name as alias to put his mistake right again, don't you think so?
Actually, I can hear him rolling in his grave. :D
------------------
I am; therefore I think.
Boris,
Interesting, if you say discovering faces, do you also mean recognising them as belonging to a face stored in memory ?
I did my thesis also on recognition(I took a masters in informatics after I graduated from physics) but this was on simple geometric objects. I made use of geometric invariants, what do you use for face recognition ?
If anything, it's rational -- because it is a belief in the ultimate triumph of rationality. If you think about the entire scientific enterprise to date, you will notice an interesting trend: no barrier to knowledge has ever proved insurmountable.
Hmm, may be we should change the subject here and work towards some kind of definition of what is truly knowledgeable and what isn't ? Or perhaps what constitutes a satisfying explanation for something ?
What do you have in mind actually when you say an actual referent ? What do you think of when you say quarks might very well have internal structure ? Do you think there is something as a particle that is undividable ? And how small do you suppose this particle is ? A mathematical point ?
These things have been tried, you know. For example an electron has always been thought to be just this very thing : a mathematical point with all its mass and charge crammed into this point. The problem with points is however that they are singularities : the electromagnetic energy to make an electron for example (this means take hypothetically the electron charge from infinity and bring it together in this one point) is infinite. Although clearly the mass of an electron isn't... There have been proposals that elementary particles were in fact black hole because since their masses are crammed into mathematical points, they are actually within their Schwarzschild radius. These theories however failed because the physics of general relativity just doesn't work on the small scales of the elementary particles.
This is why in most fundamental equations mass is actually an ad hoc hypothesis. The Dirac equations with mass included aren't even relativisticly invariant any more ! You see how desperate the situation was.
When Higgs proposed his particle it was more a desperate attempt to save what could be saved of the Standard Model. He showed a way to keep Lorentz invariance and introduce mass at the same time but in doing this he needed an other particle. Hence the desperate search for the particle in which no expenses are spared. The way mass is introduces then is by breaking the Lorenz invariance, the system then 'chooses' a mass which is dependent on more fundamental constants.
This breaking of symmetry is something very fundamental it seems. The same thing happens in gauge theory, there the gauge symmetry is broken and creates the gauge particle (like the photon).
This is actually what I think happened at the beginning of the universe : since there was nothing to begin with the symmetry of the nothing was absolute and perfect. You can compare this with a mathematical plane, every point of a plane can be transformed in any other with every possible planar transformation. Now imagine this in a hyperspace with infinite dimensions : the symmetry is astounding. Then the symmetry was broken and in breaking a choice was made, I think this was the choice for the most fundamental constant of which all others are somehow related. Once this was established more symmetry was broken and more constants were chosen in the process.
Why was the original symmetry broken ? Why not... ? Since there was nothing, there was also nothing preventing it to happen...
First of all you must realise that the more symmetry a system has, the more unstable it is, the nothing must have been the most explosive thing ever.
So to answer your questions :
1) the constants are this way because of a combination of choice and interdependence this last in a deterministic way. Once certain choices were made, the others had to follow.
2) You can explain the universe be looking at its origin, which was the nothing. In the nothing there was no charge so all charges coming from the nothing must add up to nothing. Why are there not three or more kinds of charge ? Because nature is lazy, one of the most fundamental principle on which all equations are based is the least action principle. This is why nature always chooses the easiest way or answer.
On other way of looking at it is since the whole history of the universe is actually a quest form instability to stability a two charge system is much more stable then a three, four or more charge system.
This rule also serves us if we want to know why there are only four dimensions that matter, first of all time is a nasty one and therefor I suspect that it already existed before the rest. I think time was there when nothing else was there with it.
Most of the questions you asked are actually answered by physics right now.
For example the right hand rule of magnetic fields is because of the mathematical properties of three dimensional space. Matter and antimatter annihilate because they represent what happened at the time of the big bang, again we come from nothing thus everything added together must still equal nothing.
What we did is we stole energy from the nothing but we can do that only for a limited amount of time, that is why the days of the universe are numbered, that is why everything ultimately falls apart and that is why time transcends the universe.
About rotation of elementary particles, this is a very cumbersome notion of course. If on one side particle are thought to be mathematical points then how can a point rotate ? This is again where our macroscopic views conflict with the quantum world. What you must do in these cases is simply stop to form a picture because you know it is false any way since you can't imagine things that behave as weird as electrons.
I think this is were must of your frustrations come from, what you are trying to do is force your macroscopic imagination on the microscopic world : let me tell you it is no use, our mind isn't designed for it.
May be we will be able to construct an AI that will understand the complexities, but will we still be able to understand the AI ?
3) Is there such a thing as the true nature of reality ? I do hope so but I sometimes wonder...
I hope however that this has shown that getting answers actually can be without strict determinism, determinism is still needed but not to its fullest consequences.
About the CP violation. Actually this is the same thing as saying T-violation.
There is a very general theorem that states that if a Hamiltonian is hermitical (this means that it gives real numbered eigenstates, which are the energy spectra that you measure) it has to conserve CPT symmetry. If you find CP violation then in order to conserve CPT symmetry, T needs to be violated also...
And Boris, I never said that being irrational was wrong, it adds flavour to the discussion ;) as long as you know you are being irrational...
------------------
I err, therefore I exist !
Plato,
Actually, my system is not concerned with recognition. At best, you could call it classification: a part of the system discriminates a class of objects (faces) from everything else (nonfaces) -- which is actually an exceedingly difficult problem, as the input is not normalized in any way (i.e., the system has to deal with the astonishing variety present in real-world stimuli, not some laboratory-controlled, limited-pose, limited-illumination, and limited-everything else, situation.) And I do not use any geometric or explicit mathematical models (beyond a blob-based tracker component); the system operates on a neural network, and it learns to solve the problem by being trained on a database of images. In fact, the particular approach the network found so far eludes me; I'm still trying to understand how exactly the problem is being solved (which is part of the lure of neural networks -- they are an excellent discovery mechanism.)
Anyway, if you're particularly interested in what the system does, or how it works, I'll send you the final draft of the paper when we finish it (the deadline for final draft is June 30th, so we better be done by that date.)
<hr>
What do you think of when you say quarks might very well have internal structure ? Do you think there is something as a particle that is undividable ? And how small do you suppose this particle is ? A mathematical point ?
Well, as a fundamental feature of my construct, I do not accept infinities of any type. That is, there cannot be such a thing as infinitely small, nor infinitely large. In other words, I argue that space itself is ultimately quantized. This has to be the case in order for the universe to be equivalent to a Turing machine (i.e., for it to be able to compute) -- the Universe must have a finite state description. Since "positions" of various components are part of the universe's state, it follows that there must be a finite total number of possible positions.
Due to such a proposition, it follows that there is, in reality, no such thing as a mathematical point; mathematical points are mere abstractions. They do work, but only when applied by us as observers to describe what we observe. Note how neatly it follows that there is no such thing as a true mathematical singularity, either. Information must always be preserved, even if it happens to fall into a black hole.
Now, against this backdrop of a quantized universal Matrix, everything else happens. You can think of the Matrix as a collection of "units" that individually possess various properties -- yet all the properties are defined circularly in terms of the units themselves (in other words, there cannot be any "fundamental" constants that cannot be mathematically derived from relationships between the units.) The interactions between units of the Matrix somehow generate the 3 continuous dimensions of our space (the 3 degrees of freedom in "position"). Likewise, everything from photons to electrons is a result of aggregate patterns of activity among potentially huge numbers of such units. In other words, saying that a photon has inner structure is a bit like saying that a hurricane has inner structure -- I fully expect the proportions between "fundamental" particle/wave entities and the numbers of Matrix units that compose them to be at least at the level of proportionality of the number of molecules to a single hurricane composed of them.
Now, I'm at a loss to define what the actual properties of the units have to be like. One thing seems clear, however: they possess inertia, or memory -- whatever you want to call it -- which guarantees that interactions between them only evolve based precisely on current state. In other words, a Matrix unit (or a set of them) must be describable with a Turing machine.
See, what I'm ultimately after here, is a complete unification of everything: not just matter and energy, not just fields and forces, but everything in existence including spacetime itself (and whatever may underlie it) -- into a single universal framework that precisely defines both existence of, and interrelationships between, the observables. Note that such ambitions are somewhat similar to what M-theory tries to do -- but the reason I don't like M-theory, is because its fundamental units (the m-branes) are in themselves entirely too complex (they do things like vibrations, coiling, etc, as well as possessing extent, elasticity, topoloty -- all properties identified with objects that are themselves composed of something yet more fundmental.) Also, the fundamental units of M-theory are not self-referential; they are defined in terms of concepts that indeed are more fundamental than the concept of an "m-brane" (e.g. continuity, extent, etc.) The properties of a true unit must be truly fundamental, with no simpler constructs necessary to define them, and they must not derive from anything other than the fundamental unit (i.e., no mysterious helper forces, fields, or objects are allowed.) For all of these reasons, I'm convinced that the M-theory is far from the final theory-of-everything. But M-theory might be an incremental step in the right direction.
This is actually what I think happened at the beginning of the universe : since there was nothing to begin with the symmetry of the nothing was absolute and perfect. You can compare this with a mathematical plane, every point of a plane can be transformed in any other with every possible planar transformation. Now imagine this in a hyperspace with infinite dimensions : the symmetry is astounding. Then the symmetry was broken and in breaking a choice was made, I think this was the choice for the most fundamental constant of which all others are somehow related. Once this was established more symmetry was broken and more constants were chosen in the process.
As a dynamical description, this might even be right. However, it leaves unanswered the following questions: what is "it" that contains, or defines, the symmetry in the first place? If there is something like a hyperspace in the beginning, then what gives rise to such a hyperspace? What sets up its dimensionality, what makes it continuous, what determines the total number of symmetries that were originally there, what determines the modes in which those symmetries can be broken, etc, etc, etc.
In the nothing there was no charge so all charges coming from the nothing must add up to nothing. Why are there not three or more kinds of charge ? Because nature is lazy, one of the most fundamental principle on which all equations are based is the least action principle.
But why is there such a thing as "charge" at all, in the first place? What <u>is</u> charge?
This rule also serves us if we want to know why there are only four dimensions that matter, first of all time is a nasty one and therefor I suspect that it already existed before the rest. I think time was there when nothing else was there with it.
Well, actually under my construction, time is not a dimension at all. At its root, it is merely the property of the fundamental units: they are capable of mutual interactions, and of changing state based on previous state and on those interactions. And again, why are there 3 dimensions, and not 2, 1, or none? Wouldn't 0 dimensions be more economical?
Most of the questions you asked are actually answered by physics right now.
For example the right hand rule of magnetic fields is because of the mathematical properties of three dimensional space.
You are totally missing the point. Your "explanation" is empty, because it is not based on a deduction; rather, it is based on an induction. You see, we do not deduce the "mathematical properties of three-dimensional space"; rather, we detect magnetic fields, and modify our mathematical models of 3-dimensional space to include rules that generate those same fields. The right-hand rule does not derive naturally from some fundamental mathematical definition of space; rather, it is artificially built into our very definition of that space. In other words, "explanations" of modern physics are a bit like observing the sky to be blue, writing down the law that states "the sky is blue", and then saying that the sky is blue because the law says the sky is blue. You see, such an "explanation" fails to capture the quantum-mechanical dynamics that result in the sky's color -- which are the real cause of its blueness. Modern physics is great for manipulating reality, because through its models it enables us to predict how reality will respond to our manipulations; however, modern physics provides no explanation for why reality is the way it is, nor how it really works under the covers. Such an explanation lies at a deeper level, certainly below the superficial empirical models we derive from our systematic studies.
Matter and antimatter annihilate because they represent what happened at the time of the big bang, again we come from nothing thus everything added together must still equal nothing.
But what are the exact mechanisms of annihilation? So far, we have: electron meets positron, bang, two gamma photons come out. But what happens during the "bang"? How exactly are the two particles converted into the two photons? What is the topological path such a transformation takes, what gives rise to the topology in the first place, and what determines the particular path? In other words, what happens to our model if we increasingly slow down time and expand our obsevations into ever-closer-spaced timeslices of increasing spatial resolution? You see, as a determinist I claim that were you indeed to do such an expansion (if it were indeed possible), you would obseve the finer mechanisms of annihilation, as well as the finer structure of positrons, electrons, and photons.
About rotation of elementary particles, this is a very cumbersome notion of course. If on one side particle are thought to be mathematical points then how can a point rotate ? This is again where our macroscopic views conflict with the quantum world. What you must do in these cases is simply stop to form a picture because you know it is false any way since you can't imagine things that behave as weird as electrons.
Perhaps the insight here is that an electron is not a unitary object, but rather indeed is something as complex as a weather system.
I think this is were must of your frustrations come from, what you are trying to do is force your macroscopic imagination on the microscopic world : let me tell you it is no use, our mind isn't designed for it.
Our mind isn't designed for many things that we now do -- because we adapt. Even our conceptual frameworks evolve, and arguably with evolving language and theory, we are actually capable of ever richer and more complex thought. I would consider it an open question when it comes to what human minds are ultimately capable of understanding -- even apart from the impending self-driven structural evolution of intelligence.
Is there such a thing as the true nature of reality ? I do hope so but I sometimes wonder...
I certainly hope so too.
I hope however that this has shown that getting answers actually can be without strict determinism, determinism is still needed but not to its fullest consequences.
Well, I hope to have shown that answers without determinism are shallow and not true answers -- they are more descriptions than explanations.
There is a very general theorem that states that if a Hamiltonian is hermitical (this means that it gives real numbered eigenstates, which are the energy spectra that you measure) it has to conserve CPT symmetry. If you find CP violation then in order to conserve CPT symmetry, T needs to be violated also...
Allright, admittedly I'm swimming in foreign waters here, but what about the following observation: since determinism does not allow infinities, it doesn't allow truely real numbers. Indeed, all numbers in determinism are ultimately rational, and integral at the lowest level of analysis. What does such a fact do to the theorem you mentioned?
------------------
I am; therefore I think.
[This message has been edited by Boris (edited June 01, 2000).]
Hi Boris,
In other words, "explanations" of modern physics are a bit like observing the sky to be blue, writing down the law that states "the sky is blue", and then saying that the sky is blue because the law says the sky is blue. You see, such an "explanation" fails to capture the quantum-mechanical dynamics that result in the sky's color -- which are the real cause of its blueness. Modern physics is great for manipulating reality, because through its models it enables us to predict how reality will respond to our manipulations; however, modern physics provides no explanation for why reality is the way it is, nor how it really works under the covers. Such an explanation lies at a deeper level, certainly below the superficial empirical models we derive from our systematic studies.
Thanks! You've just put the feeling that I had (that there is something wrong about some of the current theories) into words. Liberated at last (now I have something else to worry about :)).
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
Crisp,
good for you ! That is the attitude of a true scientist, always be very critical for everything (especially your own theories ;) )
Boris,
I certainly would like to see the end product of your sweat, you can mail me at gert_willems@hotmail.com I will look forward to it ;)
back to the debate :
I can see why you don't like infinities (I hate their guts also :D ) but if you are postulating a finite granularity then you must know the consequences.
You see the reason why they first postulated mathematicle points and why they postulate strings (which are 1- dimensional) as the fundamental particles is special relativity.
Suppose you have a three dimensional finite little ball as your most basic particle then this ball will, if it is accelerated to lightspeed, undergo a lenght contraction. This means that the basic particle's volume is not constant to begin with.
Second, suppose it smashes against an other particle then the side that hits will stop faster then it's far side because since it has a finite radius it takes some time (effects like that have finite speed, especially if you are allergic to infinities) for it to stop all together. This would mean however that there would be stresses withing your most basic particle and as such making it less basic for it must have internal structure if forces can work within it.
You see it ain't that simple...
Besides if every observable is ultimatly a rational number then all behavior in the universe must be periodical. This would mean that in due time there will be an other big bang and an other Boris talking to an other Plato saying the exact same things as we do now. And there is the infinity for everything would go through this enormous cirkel and would repeat itself over and over again. This is what Nietzsche believed actually so now you managed to pick those philosophies I despise the most, congradulations :D :D
Boris, all I can say is I can not accept your mechanical universe and I refuse to believe that we are actually just a simulation in a giant computer. Which is what you are ultimatly saying. This is not my idea of solving the basic questions for then I can ask : why is the computer there and who build it ?
However, it leaves unanswered the following questions: what is "it" that contains, or defines, the symmetry in the first place? If there is something like a hyperspace in the beginning, then what gives rise to such a hyperspace? What sets up its dimensionality, what makes it continuous, what determines the total number of symmetries that were originally there, what determines the modes in which those symmetries can be broken, etc, etc, etc.
You sure have a hard time asking one question at the time, don't you ;)
The symmetry is defined in mathematics of course, in mathematics we can easily define an empty space with infinite dimensions. No problemo, once you have this space you can ask yourself : ok now what are the transformations I can do that leave the space invariant. Can I turn it over some degree without changing it ? Yes, hence rotational symmetrie. Does the rotation depend on a specific axe ? No, hence spherical symmetry. Can I mirror it ? Yes, parity symmetry. And so on and so on...
What sets up its dimensionality ? That is implied in the definition of course, if you are postulating an N-dimensional space, you are assuming N dimensions of course.
The total number of original symmetries that originate in any given dimension is actually a geometrical problem of which I sadly don't posses the aswer. But I'm confident that it has been found. The modes to break them is of course very much related to the previous problem is has, I'm sure, a very distinct mathematical answer.
But why is there such a thing as "charge" at all, in the first place? What is charge?
Aha, this is a very interesting question indeed ! Charge is actually something that pops up whenever you introduce a force in an equation. You see there is this truly magnificent derivation of the electromagnetic force and the equations of Maxwell only starting from a general function that obays the least action principle. The least action integral has some inherent symmetries called Noether symmetries, this means that you can add some kind of gauge to your function without chaning it. This gauge turns out to be the photon ! It gave me an intellectual orgasm if I recall the paper well, I will try to find it back if I can ;)
This was theoretical physics at its best constructing an entire theory based on 1 fundamental assumption : the least action principle. Do you have any idea how long it took for the equations of Maxwell to be found ? There it was on nothing more then three pages ! Suddenly I couldn't understand why Euler himself didn't see this, he could have invented electromagnetism and gauge theory 100 years before Maxwell. This is not how it works of course... :(
Well, actually under my construction, time is not a dimension at all. At its root, it is merely the property of the fundamental units: they are capable of mutual interactions, and of changing state based on previous state and on those interactions. And again, why are there 3 dimensions, and not 2, 1, or none? Wouldn't 0 dimensions be more economical?
Boris, without time they aren't capable of anything ! They need time to exist and if you rather prefer to call it rate instead of time, fine but this 'thing' as a prerequisit for existence, that is why I think time must have been there before anything else...
Why three dimensions ? Because it is the smallest number of dimensions it takes to make life possible. Anything lower would never arise to life and we wouldn't be having this discussion. Anything higher would be to much effort or perhaps create some other strange effect that would prevent life from occurring... This is what I think, mind you. Although I have heard that higher dimensions would also make the standard model unrenormisable and give rise to all sorts of infinities, this would also prevent life from happening of couse which is what I was trying to say...
Your "explanation" is empty, because it is not based on a deduction; rather, it is based on an induction. You see, we do not deduce the "mathematical properties of three-dimensional space"; rather, we detect magnetic fields, and modify our mathematical models of 3-dimensional space to include rules that generate those same fields. The right-hand rule does not derive naturally from some fundamental mathematical definition of space; rather, it is artificially built into our very definition of that space.
You have every right to say this because I did try to shake off the explanation. I apologise and will try to be a bit more complete this time.
Three dimensional Euclidian space is the only one that has something that is called a vector product. This is an operations that turnes two vectors into an other vector. I'm sure you know the scalair product, this operations is defined for N-dimensions and turn two vectors into a scalair number.
The resulting vector of the vector product stands to the two others in a righthanded way. This is why magnetism follows a righthand rule since it is the vector product of the speed of a particle and the magnetic field it moves in.
Modern physics is great for manipulating reality, because through its models it enables us to predict how reality will respond to our manipulations; however, modern physics provides no explanation for why reality is the way it is, nor how it really works under the covers. Such an explanation lies at a deeper level, certainly below the superficial empirical models we derive from our systematic studies.
This is hardly something you can reproach modern physics because the question 'why' hold an infinity in itself : you can always ask 'why' again on any answer you find. It will never be 'sufficient' there is no such thing !
But what are the exact mechanisms of annihilation? So far, we have: electron meets positron, bang, two gamma photons come out. But what happens during the "bang"? How exactly are the two particles converted into the two photons? What is the topological path such a transformation takes, what gives rise to the topology in the first place, and what determines the particular path?
If you take the Feynman diagrams it is quite simple : the electron meets a photon that is travelling back in time, collides and begins to travel back in time itself, the photon however now runs forward in time. Feynman tried to explain antimatter as matter running backward in time.
I don't like this explantion however because I don't believe anything can go back in time. So maybe Dirac's explanation wasn't that bad after all : he claimed that the positron was a hole in the negative energy of which the electron was the particle, annihilation is simply putting the electron back in the hole. Of course since both have restmasses, this is converted back to energy and both had impuls this is why we need two photons to conserve that.
There is nothing that determinis their path because they actually have no path, since they have a very distinct impuls and energy all information about their possible path is lost : they are plan waves ! (I know you hate this but that is the way it is :) )
you would obseve the finer mechanisms of annihilation, as well as the finer structure of positrons, electrons, and photons.
Fine by me, but it is impossible to observe this by virtue of the Heisenberg principle. Besides why do you think that the finer structure would explain everything ? Where does the finer stucture come from ? Why is it there ? How does it give rise to quantisation at a much higher level ? For I assume that your fine structure would be like billions of billions of times smaller then what we can see ? Then how is it that such fine granularity gives rise to quantisations that are so much bigger ?
Our mind isn't designed for many things that we now do -- because we adapt. Even our conceptual frameworks evolve, and arguably with evolving language and theory, we are actually capable of ever richer and more complex thought. I would consider it an open question when it comes to what human minds are ultimately capable of understanding -- even apart from the impending self-driven structural evolution of intelligence.
I don't agree. First of all I believe that most of our abstrahation abilities actually predate our language capabilities. Primitive man must have had a high developed degree of abstract and scientific thought if he was able to read the signs of his prey that he was persuing. Since he lacked the superiour smell and sight abilities of his competitors.
Second we are talking about the structure of matter and the properties of elementary particles this is not some machine or computer that we ourselves constructed. It is something way out of our normal day to day experience level. What you are hoping is that we are just machines and thereby we would indeed be able to know everything. I am afraid to break this for you : this is not the case !
Well, I hope to have shown that answers without determinism are shallow and not true answers -- they are more descriptions than explanations.
But Boris, that is ultimatly the only thing we can do ! Describing !
If you think it would be possible to assume some premise and from that construct the whole world with it then, first of all you would be god, second of all you would be trapped in yourself. There is a whole world out there Boris, ready for discovery don't get locked into yourself !
Allright, admittedly I'm swimming in foreign waters here, but what about the following observation: since determinism does not allow infinities, it doesn't allow truely real numbers. Indeed, all numbers in determinism are ultimately rational, and integral at the lowest level of analysis. What does such a fact do to the theorem you mentioned?
Why would determinsim not allow infinities ? Determinism only states that for every cause there is exactly one effect, this cause can be something infinitly small, no problem with that.
I think you are intertwining your assumption that there is a basic granularity to the universe with determinism itself, the two are distinct things you know.
Now, to answer your question : it doesn't do anything to it. If observables must be real then they certainly are rational or integrals...
------------------
I err, therefore I exist !
Hi Plato,
good for you ! That is the attitude of a true scientist, always be very critical for everything (especially your own theories)
I am :). It took me 2 and a half months before I started to appreciate the beauty of quantum mechanics (but I must say that I still am not entirely convinced)... This will be continued in another post soon (if I ever get to it).
And now for the crisis of the day:
I can see why you don't like infinities (I hate their guts also) but if you are postulating a finite granularity then you must know the consequences...
Infinities... Mathematician's wet dream & physicist's worst nightmare.
The reasons you stated for the "elementary" building block to be one-dimensional, seem to have a wierd consequence: there is no elementary particle; since a "point" is infinitely small, whatever you propose as an elementary building block can be decomposited into smaller "points"... Okay, did I miss something here ?
Boris, all I can say is I can not accept your mechanical universe and I refuse to believe that we are actually just a simulation in a giant computer. Which is what you are ultimatly saying. This is not my idea of solving the basic questions for then I can ask : why is the computer there and who build it ?
Taking the analogy back to the real world, this question would probably rephrase to "why did the big bang occur and who caused it?". Not the mechanical, deterministic nor your incomplete deterministic description of the universe, can answer that question at this time, so with a pat on the back of Herr Occam, I'd go for the deterministic view ;).
What sets up its dimensionality ? That is implied in the definition of course, if you are postulating an N-dimensional space, you are assuming N dimensions of course.
The total number of original symmetries that originate in any given dimension is actually a geometrical problem of which I sadly don't posses the aswer. But I'm confident that it has been found. The modes to break them is of course very much related to the previous problem is has, I'm sure, a very distinct mathematical answer.
This problem is solved in the current (basic) group theories in mathematics. Using those, you can calculate how much symmetry is possible in an N-dimensional space and what combinations of linear transformations can be combined or not (eg. if can you do both a rotation and a reflection on an object in this space). The exact formulas are unknown to me since I only have a very limited knowledge of group theories.
Charge is actually something that pops up whenever you introduce a force in an equation. You see there is this truly magnificent derivation of the electromagnetic force and the equations of Maxwell only starting from a general function that obays the least action principle. The least action integral has some inherent symmetries called Noether symmetries, this means that you can add some kind of gauge to your function without chaning it. This gauge turns out to be the photon ! It gave me an intellectual orgasm if I recall the paper well, I will try to find it back if I can
Hrm... Be sure to drop it somewhere near my mailbox too please ;).
Three dimensional Euclidian space is the only one that has something that is called a vector product. This is an operations that turnes two vectors into an other vector. I'm sure you know the scalair product, this operations is defined for N-dimensions and turn two vectors into a scalair number. The resulting vector of the vector product stands to the two others in a righthanded way. This is why magnetism follows a righthand rule since it is the vector product of the speed of a particle and the magnetic field it moves in.
Just two sidenotes: The first being that the Maxwell equations of electromagnetism beautifully predict the right hand rule for electric & magnetic fields. Secondly, the fact that the resulting vector from the vectorproduct is ortogonal to the two vectors you started with is merely a coincidence (the resulting vector is actually not a vector at all but an antisymmetric tensor - for three dimensional euclidian spaces this tensor just happens to have three components ;), for 4 dimensional spaces it has 6 components).
There's another problem with indeterminism (complete or incomplete); Any indeterministic theory will never be able to predict anything (since anything you do can have different outcomes). What good is it if we can only say "hey, this nucleus will decay" when we cannot say "now", "tomorrow" or "in 10^30 years" ? Isn't the aspect of prediction the most important goal in physics ? I simply cannot be satisfied with an answer like "there's a 50% chance that this won't kill you" when somebody hands me over a bar of uranium. Will it or won't it ? (author's sidenote: do not try this at home 'coz it will kill you - at least, in my deterministic point of view).
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
The first being that the Maxwell equations of electromagnetism beautifully predict the right hand rule for electric & magnetic fields. Secondly, the fact that the resulting vector from the vectorproduct is ortogonal to the two vectors you started with is merely a coincidence (the resulting vector is actually not a vector at all but an antisymmetric tensor - for three dimensional euclidian spaces this tensor just happens to have three components , for 4 dimensional spaces it has 6 components).
Exactly, very finely put ! I have some rust on my mathematical background but this is indeed how I remember it now, thank you Crisp.
Isn't the aspect of prediction the most important goal in physics ?
This is a metaphysical question actually and I don't agree with it. We aren't concerned in prediction but rather in understanding. These are two very distinct points. If it so happens that nature cannot be predictable then I want to know the reason why.
This is what is important, not the prediction. We aren't concerned with truth saying or astrology. Those are things that belong in the realm of magic and phantasy.
Besides, think about it what would the world be like if you could predict everything that will happen ? This is what Boris is after.
First of all you would be equal to God. Very nice at first glance but at second glance you would have created a prison for yourself of which there is no escape possible. This fate would be worse then Hell ! And what is even worse you would be able to predict your own insanity to the finest details : this is the ultimate consequence of determinism !
Hmm, quite dramatic ending don't you think ? May be I should become a story writer ? Then again, I probably make to many mistakes... ;)
------------------
I err, therefore I exist !
Plato,
First of all, what was that:
Besides, think about it what would the world be like if you could predict everything that will happen ? This is what Boris is after.
??? How many times do I need to repeat that my position actually makes prediction of "everything" impossible, before the point sinks in? Hello, this is not at all what I'm after!! Knock-knock?
<hr>
And now, on with the grind...
Suppose you have a three dimensional finite little ball as your most basic particle then this ball will, if it is accelerated to lightspeed, undergo a lenght contraction. ... This would mean however that there would be stresses withing your most basic particle and as such making it less basic for it must have internal structure if forces can work within it.
I do not see why either should follow. Clearly inertia, repulsion, attraction, mass, spatial extent, shape, length contraction, or structure are all secondary qualities that arise from interactions of the basic units. The units themselves obviously cannot possess such properties, since otherwise they would not be fundamental. You see, I hope that eventually we will not only be able to unify all of our knowledge into a single framework, but even explain the existence of particular properties within our experience -- such as shape, inertia, length contraction, or mass, for example.
Besides if every observable is ultimatly a rational number then all behavior in the universe must be periodical.
I can't believe this. We've discussed the issue before, haven't we? Were you paying <u>any</u> attention? Here's a quote from my previous post:
This is not at all the case. Consider the following Turing machine:
<pre>
start: print "hello, world!", go to loop
loop: print "I'm stuck!", go to loop
junk: print "that's not possible!"
</pre>
Obviously, the machine has only three possible states. Obviously, the machine never halts. Obviously, the machine repeats its "start" state only once, no matter how long you wait. Obviosly, the machine never even enters one of its states -- ever. What's going on here? Isn't the machine deterministic? You betcha -- and the resolution to the paradox is.....that it is NOT a requirement for a deterministic system to exhaust all of its possible states, even given an infinite amount of time. In fact, it would be an amazing, next to impossible, freak occurrence if a Turing machine with as complex a state as the Universe, naturally arose with such a structure that it was doomed to not only go through all of its possible states, but also to continue repeating all of them as time passed!
The second law merely argues that the universe is constrained to shift state only in direction of increased entropy. This does not mean that entropy is going to increase at the same rate forever (which seems to be your assumption) -- this would imply a truly infinite amount of matter/energy in the universe (since "entropy" represents the amount of disarray in matter/energy), while we know that the amount is finite. What is happening, is an exponential drop-off in growth of entropy as the universe ages. As time passes and entropy increases ever slower, the total number of possible states that the universe can transition toward based on its current state, shrinks. In the infinite time limit, the universe will reach the state or the set of states with the lowest possible entropy -- and from then on, it will just cycle within that state or set of states, forever.
Now, I should hope this particular issue can be put to rest now??
Boris, all I can say is I can not accept your mechanical universe and I refuse to believe that we are actually just a simulation in a giant computer. Which is what you are ultimatly saying. This is not my idea of solving the basic questions for then I can ask : why is the computer there and who build it ?
First of all, I repeat Crisp's point: your approach has even less of a chance to answer that particular question than does mine. Secondly, the basic questions I'm talking about are apparently the type of question you never even bothered to ask. For example, what gives rise to those systems of coordinates of which you are so fond?
What sets up its dimensionality ? That is implied in the definition of course, if you are postulating an N-dimensional space, you are assuming N dimensions of course.
Sigh.... You did not understand the question. Let me try to rephrase it: what gives rise to your concept of an N-dimensional space, in the first place? Don't say it's mathematics, because that's not what I'm asking. What I'm asking is: what is it that generates the mathematics in the first place, and how is that done?
Charge is actually something that pops up whenever you introduce a force in an equation. You see there is this truly magnificent derivation of the electromagnetic force and the equations of Maxwell only starting from a general function that obays the least action principle. The least action integral has some inherent symmetries called Noether symmetries, this means that you can add some kind of gauge to your function without chaning it. This gauge turns out to be the photon !
Here's what you are missing in this picture. Forget gauges, and focus your attention on the very fundamental concept of a manifold. Ask yourself: what is the real-life equivalent of a mathematical manifold? In other words, what is it that the manifold represents? Where does that "something" come from?
This was theoretical physics at its best constructing an entire theory based on 1 fundamental assumption : the least action principle.
See, this is exactly the kind of elegance that I'm after. Not dozens and dozens of fundamental assumptions, but a scant one or two -- from which arises everything, including space, time, energy, matter, and mathematics itself.
Why three dimensions ? Because it is the smallest number of dimensions it takes to make life possible.
So, your ultimate answer to any questions concerning the "fundamentals" of our existence, is the anthropic principle? It is so because it is so? Why, then, bother to discover <u>any</u> mechamism behind <u>anything</u>?
The resulting vector of the vector product stands to the two others in a righthanded way. This is why magnetism follows a righthand rule since it is the vector product of the speed of a particle and the magnetic field it moves in.
This is laughable, and for a very simple reason. The vector product gives you a right-handed result because it is being applied within a right-handed coordinate system, and has been defined to be a right-handed operator. You never answered the real question: why are our coordinate spaces right-handed, as are our vector operators? The answer is, because such constructs simplify our symbolic models of empirical objects. But the real real question is: why should empirical objects exhibit right-handedness in the first place? Certainly not because we have defined our mathematics to mirror the right-handedness!!
This is hardly something you can reproach modern physics because the question 'why' hold an infinity in itself : you can always ask 'why' again on any answer you find. It will never be 'sufficient' there is no such thing !
The question may never exhaust itself, but what we can do is narrow down the domain within which the question applies. Pre-science, the question was unanswered with respect to many things whose mechanisms and causes we have since determined. We can continue to expand our base of knowledge and explanations, all the way down to some fundamental construct from which everything eventually derives. When we get there, there are two possibilities. Either there will be no way to answer the questions of "how" and "why" with respect to that fundamental construct, or through its very definition it will point us to the answers. Until we have reached that point, however, the most productive and worthwhile thing we can do is try to reach it.
If you take the Feynman diagrams it is quite simple : the electron meets a photon that is travelling back in time, collides and begins to travel back in time itself, the photon however now runs forward in time.
Even aside from the time-travelling thing, what underlies the process of "collision" that is presupposed here? Through what mechanisms is the collision accomplished, through what mechanisms does it result in changed spacetime trajectories of the objects involved?
So maybe Dirac's explanation wasn't that bad after all : he claimed that the positron was a hole in the negative energy of which the electron was the particle, annihilation is simply putting the electron back in the hole. Of course since both have restmasses, this is converted back to energy and both had impuls this is why we need two photons to conserve that.
How are the restmasses "converted back to energy"? Through what pathways is the impulse conserved? What is this "negative energy", and how can it have a hole in it?
I'll keep pestering you with such questions, until one day you will hopefully realise that modern physics does not possess any answers. It completely glosses over the issues of fine structure and fundamental mechanisms, which enables it to maintain its nondeterministic flavor, but strips it of any real explanatory power.
There is nothing that determinis their path because they actually have no path, since they have a very distinct impuls and energy all information about their possible path is lost : they are plan waves !
No, what I'm talking about here is not "path" as "trajectory" within spacetime. What we are talking about is: a topological configuration (a) is being transformed into a topological configuration (b), where the topology is defined over some parameter space. The natural assumption would be that the topological transformation is smooth. Hence, at certain instants during the process, we would actually have intermediate configurations that cannot be classified as either (a) or (b). The question is, what path in the topological space, what trajectory, does the transformation take? And what generates such a trajectory?
Fine by me, but it is impossible to observe this by virtue of the Heisenberg principle. Besides why do you think that the finer structure would explain everything ? Where does the finer stucture come from ? Why is it there ? How does it give rise to quantisation at a much higher level ? For I assume that your fine structure would be like billions of billions of times smaller then what we can see ? Then how is it that such fine granularity gives rise to quantisations that are so much bigger ?
First of all, I've already argued that direct observation is not the only way to test theories. Hence, I would be very surprised if, given a theory of the fine structure, we couldn't figure out ways to detect its indirect effects, regardless of the uncertainty principle. Not to mention that I fully expect any theory of the fine structure to actually provide numerical or even analytical derivations of the many "constants" that we empirically measure -- which would be a triumph in itself.
Secondly, no theory of fine structure would explain <u>everything</u>. Naturally, it would involve some fundamental entities that possess no explanation by their very virtue of being fundamental. However, it would explain a great many things which are currently unexplained. So, it would fit in nicely within the general evolution of scientific knowledge.
As to the questions you ask, they are all excellent questions. However, if I could answer them I wouldn't be here writing these posts; I'd be busy spending my Nobel prize money at some tropical resort. But don't think such questions are not bugging me on a daily basis.
Me:
Even our conceptual frameworks evolve, and arguably with evolving language and theory, we are actually capable of ever richer and more complex thought. I would consider it an open question when it comes to what human minds are ultimately capable of understanding -- even apart from the impending self-driven structural evolution of intelligence.
You:
I don't agree. ...
Ok, just a simple example. Imagine what it would be like to describe to a caveman the concept of being stuck in traffic. Point is, with expanded conceptual frameworks we can conceive of a great many more things than we otherwis would be capable. Language is intimately intertwined with cognition, and the two are engaged in a perpetual feedback cycle. Just think about the difference betwee a human that possesses any language at all, and a human who grew up without ever learning a language; one of them will have vastly superior mental capabilities (can you guess which one?)
But Boris, that is ultimatly the only thing we can do ! Describing !
If you think it would be possible to assume some premise and from that construct the whole world with it then, first of all you would be god, second of all you would be trapped in yourself. There is a whole world out there Boris, ready for discovery don't get locked into yourself !
I disagree. If you were faced with a clock, you could describe it allright -- but if you were a little bit more curious, you might also discover and explain the mechanisms that make it tick. We are surrounded by all sorts of clocks, but all we've done so far is give them names and measure their dimensions.
And actually, I'd rather think that a theory of fine structure (I like that phrase!) would be a mechanism of discovery rather than a mental prison. It would, in all likelihood, suggest entirely new phenomena that we would otherwise never even search for, much less discover.
Why would determinsim not allow infinities ? Determinism only states that for every cause there is exactly one effect, this cause can be something infinitly small, no problem with that.
I think you are intertwining your assumption that there is a basic granularity to the universe with determinism itself, the two are distinct things you know.
Ok, I wasn't clear on it. There are a couple of different ways to think of determinism. One is to think that determinism merely means that everything in the world is describable with functions (1-1 mappings). Another way to think of determinism, is that it provides <u>mechamisms</u> through which all phenomena are realized. And if you think about it that way, then through what mechanism can you possibly implement infinity?
In other words, it is my assumption that mathematics is merely a symbolic language for describing reality. Hence, any reference mathematics makes to the real world, must possess a real-world "implementation" (provided the mathematical theory is correct, of course.) So the question is, how do you implement infinity?
Now, to answer your question : it doesn't do anything to it. If observables must be real then they certainly are rational or integrals...
But they can no longer be irrational or transcendental, can they? I should think that alters the entire concept of what a function is; indeed it forces one to think back to the set-theoretical definition of functions. Ultimately, a function is merely a mapping from one set onto another. As such, it doesn't have to be analytical, for example -- but what really matters, is that the properties of the sets also define the properties of the functions. If we are to change the very domain and range of a function, then any theorems that were valid over its previous definition may no longer apply.
------------------
I am; therefore I think.
Crisp,
I have found the article ! Rejoice !
"Derivation of Maxwell's equations from the gauge invariance of classical mechanics" Donald H. Kobe, Am. J. Phys. 48(5), May 1980, p 348-353.
I hope you have the American Journal of Physics in the library of the physics department of Leuven. If not, you can always come to Gent (de wetenschapsbibliotheek bevindt zich aan de Sterre campus), that is where I got it.
Boris,
??? How many times do I need to repeat that my position actually makes prediction of "everything" impossible, before the point sinks in? Hello, this is not at all what I'm after!! Knock-knock?
"Knock-knock?" Hmm, you are almost beginning to sound like Lori here :D :D
I'm sorry that I keep repeating this but you keep giving this impression... For example if you are stating that observables can only take rational values, for me this means that you will be able to measure them exactly and thus via your deterministic theory predict their future exactly. What am I not getting here ?
I do not see why either should follow. Clearly inertia, repulsion, attraction, mass, spatial extent, shape, length contraction, or structure are all secondary qualities that arise from interactions of the basic units. The units themselves obviously cannot possess such properties, since otherwise they would not be fundamental.
This is not true, Boris. If you are saying "interaction" you are already implying the whole shabam of repulsion, attraction, charge, dimensions, etc. These things are your first premisses, they aren't constructed from more basic mechanisms.
I can't believe this. We've discussed the issue before, haven't we? Were you paying any attention? Here's a quote from my previous post:
Don't be so hasty in your debate, Boris. It seems we are talking next to each other here.
My claim is that deterministic theory gives rise to periodicity for everything.
What you are saying is that deterministic theories don't exhaust every possible state.
These are clearly two distinct cases who can be true at the same time. And they are...
As time passes and entropy increases ever slower, the total number of possible states that the universe can transition toward based on its current state, shrinks. In the infinite time limit, the universe will reach the state or the set of states with the lowest possible entropy -- and from then on, it will just cycle within that state or set of states, forever.
You see, this is inconsistent ! You are using an indeterministic claim : namely that information is not preserved and then use it to show that a deterministic theory of the universe would not by cyclic. You will have to do better then this I'm afraid.
Secondly, the basic questions I'm talking about are apparently the type of question you never even bothered to ask. For example, what gives rise to those systems of coordinates of which you are so fond?
I haven't made any claim about coordinate systems this would be stupid of me because general relativity shows us that no coordinate system is to be preferred above any other one. The coordinate systems are our own inventions to make sense of it all ! There is nothing physical about them.
what gives rise to your concept of an N-dimensional space, in the first place? Don't say it's mathematics, because that's not what I'm asking. What I'm asking is: what is it that generates the mathematics in the first place, and how is that done?
Very clever Boris, but you are just bouncing the ball back without doing something with it. Did I say that the nothing had dimensions ?
What I meant to say was that even they are absent so your universe-in-potention can choose any dimension it wants. This I would like to add is even one more symmetry : namely a dimensional symmetry of the nothing.
Ask yourself: what is the real-life equivalent of a mathematical manifold? In other words, what is it that the manifold represents? Where does that "something" come from?
I don't think that is a valid question. We use mathematics as a tool to describe and try to understand the universe. What you are asking is where does the tool come from ?
We invented it ! It is en emergent property of our cultural evolution on this planet.
Mathematics isn't something that is constructed by the basic universe, it is a language that we invented to enable us to 'talk' with the universe, this is ultimatly what physics and science is all about : a dialogue with nature. May be in a different, alien civilisation they invented an other kind of language...
So, your ultimate answer to any questions concerning the "fundamentals" of our existence, is the anthropic principle? It is so because it is so? Why, then, bother to discover any mechamism behind anything?
Ok, the anthropic principle was a lame excuse for me saying I don't know that one. But I don't have all the answers. I do know that super string theory gives a rather interesting answer to the question of why exaclty this many dimensions. I suggest you read a book about it. But first perhaps read a book about quantum mechanics and gauge theory because they are the basics of what string theory is talking about.
In the previous discussions with you I have come to realise that you actually adhere still a very classical philosophy as basic starting ground to understand the modern physics.
You see you cannot believe at the same time in a global referential frame and accept length contraction and time deletion.
You cannot at the same time believe that time is simply an internal parameter and talk about space-time distortions of black holes.
You cannot at the same time believe in a deterministic universe and accept the fact that energy is quantised.
You cannot at the same time state that observables may only be rational numbers and accept something like the spherical symmetry of the gravitational force since this involves something like Pi which is as trancendental as you can get !
This is laughable, and for a very simple reason. The vector product gives you a right-handed result because it is being applied within a right-handed coordinate system, and has been defined to be a right-handed operator. You never answered the real question: why are our coordinate spaces right-handed, as are our vector operators?
What is laughable is that you don't seem to know that vector procucts are defined regardless of any coordinate systems. That they can be used to define a coordinate system in three dimensional space. They are righthanded because they are positive with regard to the coordinate system that you choose. We can do everything with lefthanded coordinate systems and negative vector products without changing anything of the basic observables.
. Either there will be no way to answer the questions of "how" and "why" with respect to that fundamental construct, or through its very definition it will point us to the answers. Until we have reached that point, however, the most productive and worthwhile thing we can do is try to reach it.
amen !
what underlies the process of "collision" that is presupposed here? Through what mechanisms is the collision accomplished, through what mechanisms does it result in changed spacetime trajectories of the objects involved?
This, I can answer : virtual bosons. Bosons are particles with integer spins and they arise when the local gauge field of it's internal symmetry is quantised. The virtual bosons are particles that are created and destroyed before they completed a wavelength.
About charge : conservation of charge is due to an internal symmetry of the wavefunction : it is symmetric in regards to phase transformations. \psi' = e^{i\theta}\psi. With \theta any real number.
If you make this phase symmetry local, QED arises as if by magic ! I just love gauge theory.
I'll keep pestering you with such questions, until one day you will hopefully realise that modern physics does not possess any answers. It completely glosses over the issues of fine structure and fundamental mechanisms, which enables it to maintain its nondeterministic flavor, but strips it of any real explanatory power.
What does it take for you to realise that something can be incomplete deterministic and give a perfectly satisfying explanation at the same time. There is no relation what so ever between determinism and complete explanation of a system.
------------------
I err, therefore I exist !
Plato,
Wow, what a great post. You've just given me enough to write an entire chapter about!
For example if you are stating that observables can only take rational values, for me this means that you will be able to measure them exactly and thus via your deterministic theory predict their future exactly. What am I not getting here ?
There are a number of things you are not getting.
First of all, even if determinism ultimately rules, that does not mean we will ever be able to measure anything <u>exactly</u>. I am well aware of the uncertainty principle, and my take on it is simple: when we are trying to measure the exact parameters of quantum objects, we are doing something in effect reminiscent of drilling a tooth with a jackhammer. The very fact that we are made of the same stuff we are trying to measure precisely, prevents precise measurement. We can shoot photons at large-scale objects, and collect the rebounding photons to gain detailed information. If we were trying to shoot photons at a quantum or indeed subquantum object, it would be like trying to get a detailed description of a lightbulb's shape by shooting cannonballs at it. Using a wave description of light, we know that positional measurement precision grows linearly with wavelength; yet impulse imparted by a photon also linearly grows with wavelength. Hence, by increasing precision of positional measurement, you are imparting a greater disturbance upon the velocity of the target object. Conversely, by minimizing inertial impact you lose positional precision. That's all there is to it. The only reason we can't do better that this, is because of the tools that we have available -- i.e., as long as we use electromagnetism to make our measurements, we are forever limited in resolution (and there may never be any alternative to electromagnetism.)
Secondly, even if we could somehow measure exact parameters of a single quantum object, we still would not be able to predict its behavior for any extended period of time -- because it is merely one of the countless specks within a roiling quantum mess. To predict the behavior of an entire system, composed potentially of say, some 10^30 such objects, we would need to precisely measure that many parameters -- <u>simultaneously</u>. This is impossible for a variety of reasons. One is the sheer impossibility of implementing instantaneous data collection of such magnitude. Another is the relativity of simultaneity, which prevents us from <u>exactly</u> synchronizing any two spacelike separated processes (rendering us unable to measure exact time intervals between events.) A third might be quantum nonlocality, which actually links together all the quantum objects within the universe into a web of instantaneous interactions; hence, we would need to precisely measure the parameters of every single quantum object in the universe in order to be able to predict the future without any uncertainty -- which is of course impossible not only physically, but even mathematically.
So you see, even though a deterministic theory presupposes that the universe is one big Turing machine, it gives us no chance of measuring that machine's current state. And if you don't know the precise current state of a Turing machine, you cannot precisely determine the next state.
This is not true, Boris. If you are saying "interaction" you are already implying the whole shabam of repulsion, attraction, charge, dimensions, etc. These things are your first premisses, they aren't constructed from more basic mechanisms.
Not at all. Just as temperature of a gas arises from kinetic movements of its molecules, so do I fully expect that "whole shabam" of "first premises" to derive from the interactions between the units. Of course, "interaction" as I use it no longer fits the classical physics usage of the word; it merely means interaction in a more mundane sense -- it assumes an exchange of information between the units, but it does not assume the means through which information should be exchanged (indeed, defining such means would go a long way toward formulating the complete theory.)
My claim is that deterministic theory gives rise to periodicity for everything.
What you are saying is that deterministic theories don't exhaust every possible state.
...
You see, this is inconsistent ! You are using an indeterministic claim : namely that information is not preserved and then use it to show that a deterministic theory of the universe would not by cyclic. You will have to do better then this I'm afraid.
Ok, I indeed said that deterministic machines don't have to exhaust every possible state. But to say that information is not preserved is diametrically opposite from what I was trying to express. It is precisely due to conservation of information, combined with growing entropy, that periodicity is prevented. Though I how you can get confused by what I mean by "information". You could have thought that the information I'm talking about is inversely related to entropy (or directly related to degree of order) -- so that as entropy grows, information is destroyed. However, such a concept of information is incomplete.
In reality, information is truly contained in the very parameters of every single fundamental entity in the universe at a particular moment in time. This information stays fixed -- i.e., the universe has a fixed number of fundamental parameters, and that number cannot change. Which is another way to state the law of conservation of "matter" (not really matter, but the analogy holds). Whithin that set of parameters, an exchange takes place that deals with another type of information -- information encoded in the actual values of the parameters. Again, the exchange is a zero-sum process, so that whenever a parameter's value increases, some other value must decrease to compensate. This is another way of expressing conservation of "energy" (again not really energy, but analogous.)
Classically, entropy maximum has been defined as 0 information, while entropy minimum as maximal information. However, what "information" truly means in this context, is a <u>relative</u> degree of disorder between two systems -- i.e. if we were to quantify disorder, then the information contained in system A over system B is merely a negative of the difference between their measures of disorder. Within such a construct, it is not correct to think of information destruction -- rather, one should think of disorder equalization. Whereas at some point there might be a gradient in disorder between A and B, over time that gradient will disappear as disorder flows from high concentrations toward low concentrations. This is basically transfer of heat -- heat is never destroyed, it is merely equalized.
What seems to have happened to the universe, is that it started out in a very homogeneous, equalized state. Something disturbed that state, and touched off a cascade of chain reactions that, at first, destabilized the universe even further (by some kind of inertia, apparently) -- but the universe has since been on a trajectory toward maximizing its homogeneity. What we would conceive of as local aggregations of information (such as stars, planets, life) are merely eddies within this much larger disturbance -- and just like all eddies must eventually do, ours will, with time, dissipate.
Note that there is nothing indeterministic about the picture I just attempted to draw. So, please explain why you keep insisting that this is not compatible with determinism (indeed, I always rather thought that the very picture emerges from determinism!)
Now, given all that, it should be clear that a deterministic universe constrained toward equalizing disorder will not cycle -- for any true cycle would involve a reversal of the flow of disorder, which is kind of like creating a perpetual motion machine.
The coordinate systems are our own inventions to make sense of it all ! There is nothing physical about them.
No? Then what is an interval? What is a metric? What makes for relationships such as in-between vs. outside? What is it that defines such properties as in-a-plane, vs. out-of-plane? Don't tell me we made it all up, because I'll slap you upside the head every time you put one foot in front of the other.
Did I say that the nothing had dimensions ?
What I meant to say was that even they are absent so your universe-in-potention can choose any dimension it wants.
No, it is you dodging the question. Even if you presuppose that at the outset the universe had a set of configurations to choose from, you still cannot deny that those configurations must have already been defined prior to the choice, and you cannot avoid the question of what it is that gives existence to those configurations (i.e., configurations of <u>what</u>?)
We use mathematics as a tool to describe and try to understand the universe. What you are asking is where does the tool come from ?
We invented it ! It is en emergent property of our cultural evolution on this planet.
Mathematics isn't something that is constructed by the basic universe, it is a language that we invented to enable us to 'talk' with the universe, this is ultimatly what physics and science is all about : a dialogue with nature. May be in a different, alien civilisation they invented an other kind of language...
Horseshit. We invented nothing; mathematics was abducted directly from our interactions with the environment. Mathematics is a language allright, but it does not come off the top of our heads -- it derives directly from nature. That is why it is argued that mathematics is the only universal language; if you ever meet sophisticated intelligent aliens, they will "speak" the same mathematics you do (as long as they come from the same universe, that is.)
I hate the direction this is taking, but I'm afraid it's back to the old 2+2 debate. You would agree, wouldn't you, that 2+2=4 is true not because we define it that way, but because we observe it that way? Of course, we could always define anything we want to be "true" by virtue of its definition; however <u>applied</u> mathematics is true by virtue of more than merely definition -- it is true by virtue of reflecting the observed properties of our world.
Hence, it is a fundamental fallacy to regard any abstract mathematical model as a basic, irreducible explanation of any physical system. (Lest there be any mistake, this is indeed a direct assault on the Copenhagen philosophy.) Whenever mathematics is applied to model physical systems, it represents real objects and real properties.
You see you cannot believe at the same time in a global referential frame and accept length contraction and time deletion.
I can if I realize that the global reference frame is not accessible (at least not easily) through electromagnetic phenomena -- because such phenomena always occur relative to one another.
You cannot at the same time believe that time is simply an internal parameter and talk about space-time distortions of black holes.
I can if I merely restrict time from going backward. I can still talk about differentials in rate of events. As for metric distortions, I would like to ask you what it is you think that embodies the instantaneous metric at any point in "spacetime"? For that matter (and yet again), what is it that our concept of "spacetime" represents; what is its fundamental nature?
You cannot at the same time believe in a deterministic universe and accept the fact that energy is quantised.
Actually, it is the quantization of energy that was one of the big hints that originally drove me to wonder if the Universe in its entirety is ultimately quantized. I can think of ways to form quanta from quantized substrates. I cannot think of ways to form quanta from continuous substrates. In fact, the quantum mechanics' mixture of quanta (essentially integer arithmetic) with continuous fields (real number arithmetic) has always struck me as a grotesque amalgam -- a hack, at best.
You cannot at the same time state that observables may only be rational numbers and accept something like the spherical symmetry of the gravitational force since this involves something like Pi which is as trancendental as you can get !
And I thought you were against absolute precision! Ever heard of approximation? Even a circle drawn on your screen (a grid of discrete pixels) forms a recognizable geometric shape. Point is, the "exact" constants, such as PI, defined by our mathematics are in reality not exact; their precision only goes as far as the resolution of the fundamental structure. It is only because large-scale objects are composed of such fine and many discrete building blocks, that we perceive continuity -- unless, that is, we begin to probe reality at quantum resolution. My claim is that in turn, any "continuity" we still observe at quantum scale turns into complete discreteness at the fine structure scale.
We can do everything with lefthanded coordinate systems and negative vector products without changing anything of the basic observables.
Man, how explicit do I have to get? You just restated my point! Why do you think that, were we to choose a left-handed coordinate system, we would need to compensate with negative signs in order to match the "basic observables"? Is it not precisely because right-handedness is <u>a property of the basic observables</u>? Here is my question again: why is right-handedness a property of the basic obsevables??
<hr>
With respect to the finer points of gauge theory derivations, I cannot comment because I don't know what I'm talking about -- so I'll stick to the topics I can discuss in a somewhat informed manner. I know, one of these days I must teach myself QED, but until then I still think I have a case to make even based on the little that I know.
------------------
I am; therefore I think.
Hi Plato & Boris,
Wow, this discussion is really heating up (perhaps one day this forum will get hotter than the "religious debate" one ;)). Anyway, loads of stuff to catch up with...
Plato,
I have found the article ! Rejoice !
"Derivation of Maxwell's equations from the gauge invariance of classical mechanics" Donald H. Kobe, Am. J. Phys. 48(5), May 1980, p 348-353. I hope you have the American Journal of Physics in the library of the physics department of Leuven. If not, you can always come to Gent (de wetenschapsbibliotheek bevindt zich aan de Sterre campus), that is where I got it.
No problem, even at the LUC where I am studying now (Leuven won't be 'till in a few months) we have a whole collection of AJP. I'll look up the article once I get around to it (exams in one week so I have some other stuff on my mind now).
Back to the debate:
What is laughable is that you don't seem to know that vector procucts are defined regardless of any coordinate systems. That they can be used to define a coordinate system in three dimensional space. They are righthanded because they are positive with regard to the coordinate system that you choose. We can do everything with lefthanded coordinate systems and negative vector products without changing anything of the basic observables.
Well, I hate to say this, but I think both you and Boris got it the wrong way (feel free to correct me aswel); The vectorproduct is NOT a vector. The resulting antisymmetric tensor actually has nine components, of which three are zero, and hence, because of the antisymmetry, only three need to be known to write the entire tensor. Physicists (lame as we are) just write the three components as a vector, but once you get around to doing stuff like transformations on the vectorproduct, you'll see that it does not behave like an ordinary vector. Example: the vectorproduct of two vectors in one plane is indeed ortogonal to that plane (more on this in a second), but when you mirror the vectorproduct in respect to that very plane, the vector does not change! It transforms completely different than any other "vector" in the three-dimensional euclidian space.
Hence talking about coordinate systems constructed from vectorproducts is a tricky business, since any of those bases will not transform regularly.
Now about the ortogonality of the vectorproduct; this is purely a coincidence that follows from the definition of that tensor I was talking about. Okay, in the early days the vectorproduct was probably invented to construct a vector ortogonal to the two you start with, but in the meantime mathematics has shown that it's not all that simple.
What does it take for you to realise that something can be incomplete deterministic and give a perfectly satisfying explanation at the same time.
I am begging for an example here.
There is no relation what so ever between determinism and complete explanation of a system.
Isn't this exactly what determinism is fundamentally all about ? Whether you regard determinism as a 1-1 causilty or an "underlying mechanism" (which are equivalent btw), it all comes down to one thing: being able to exactly predict how a system evolves once initial parameters are known. As Boris already argued, this is practically impossible, but once again, in theory it could be done... (and why do I suddenly have the feeling that the words "in theory" will be bounced back to me twice as hard ;)).
Boris,
Just as temperature of a gas arises from kinetic movements of its molecules, so do I fully expect that "whole shabam" of "first premises" to derive from the interactions between the units. Of course, "interaction" as I use it no longer fits the classical physics usage of the word; it merely means interaction in a more mundane sense -- it assumes an exchange of information between the units, but it does not assume the means through which information should be exchanged (indeed, defining such means would go a long way toward formulating the complete theory.)
Sounds very nice indeed, but I have one problem here: you strive to know the exact mechanism on how "information" is exchanged between your units, but your theory cannot predict anything until that very same mechanism of interaction is postulated somewhere. For example, you could argue that the interactions are purely energetic in form (which is my belief btw), but how would you explain repulsion and attraction between charged particles ? Somewhere in your theory you would have to argue "if this representation of energy (let's say positive charge), meets another representation of energy, (and why not negative charge), then this or that will happen".
Although probably not very clear from the example, you'll need at least one postulate describing interactions (pretty much like the Schrodinger equation in QM, or Newton's second law).
No? Then what is an interval? What is a metric? What makes for relationships such as in-between vs. outside? What is it that defines such properties as in-a-plane, vs. out-of-plane? Don't tell me we made it all up, because I'll slap you upside the head every time you put one foot in front of the other.
I'm afraid I'm going to get a beating of a lifetime here, but Plato's pulling the right end here. Intervals, inside and outside are all human inventions (how would you define "outside" ? It's something we, as humans, choose). The same goes for coordinate systems. Coordinate systems are only a mathematical aid to describe physical systems, and it is only logical that the physical properties of a system cannot change when the observer decides to use another coordinate system.
Now I see what your point is; the distance between two objects is "universal", a property of reality (let's not take relativistic effects in account here), and so is position. But eventually it all comes down to a choice of coordinates, and these are non-realistic in nature. Saying you're outside a plane is exactly the same as saying your inside "the outside" of the plane. But heck, this is all referential frames stuff and you guys know a lot more about that than I do :).
Here is my question again: why is right-handedness a property of the basic obsevables??
Then here's my question to you: how would you explain it in terms of your units ?
The question might sound unrelated at first, but allow me to explain; My first answer to your question would be "because the Maxwell equations predict it that way". Realizing that I would get verbally slaughtered for that answer, I thought of how QED might explain it, but then it suddenly struck me: you can twist and turn as much as you like to, but somehow it must follow from the postulates of the theory you want to explain it with. Pretty obvious ofcourse, but how can you explain the very same phenomena that you are making assumptions about in the postulates of your theory ? Cyclic reasoning or not ? You can explain and understand why an object falls towards earth, but this explanation is based on a postulate (eg. Newton's second law) and hence every explanation you give is never a fundamental property of nature but a human invention. This somehow puts some very serious restrictions on the amount of phenomena you can explain.
Having said that, I am even wondering why I am discussing here since every post I read and think about makes me doubt more and more of the physical theories we have... This cannot be good :).
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
[This message has been edited by Crisp (edited June 05, 2000).]
Boris & Crisp,
I would love to continue this discussion A.S.A.P. we are getting closer and closer to some kind of consensus, I can feel it. Although it may not look at all this way at this point.
However severe time constraints restrict me from furthering this discussion into the realm of synthesis. I will get back as soon as I can, hopefully today.
Ok people, let's roll !
...The only reason we can't do better that this, is because of the tools that we have available -- i.e., as long as we use electromagnetism to make our measurements, we are forever limited in resolution (and there may never be any alternative to electromagnetism.)
That is hardly the case, in fact we are doing measurments with the weak force (otherwise we couldn't detect neutrino's since they only interact through this weak force) gravitywave will soon become a means to probe the far reaches of space since we are now building large stations like the ligo detectors (http://webplaza.pt.lu/public/fklaess/html/LIGO.HTML) to pick up this weakest of all forces.
The problem is, they all exibit the same properties as what you said about electromagnetism. So actually what you are saying is : you believe that somehow the world is deterministic but for all practicle purposes we must assume that it is indeterministic. Isn't this a good place for Occam's Razor ?
"interaction" as I use it no longer fits the classical physics usage of the word; it merely means interaction in a more mundane sense -- it assumes an exchange of information between the units, but it does not assume the means through which information should be exchanged (indeed, defining such means would go a long way toward formulating the complete theory.)
Look Boris, 'exchanging information' as you put it must involve in the most general case a carrier of this information. The non-locality of quantummechanics would suggest that their could be a way of circumventing this but that is an illusion because this very non-locality is nescessary and sufficient for Heisenberg uncertainty. This means a breakdown of information. So information can only be transferred locally, as a package.
You see how much assumptions you are already making if you simply use the frase : basic particles interact.
...This is basically transfer of heat -- heat is never destroyed, it is merely equalized.
You should better use the term 'energy' in this context. But Boris, entropy is not a deterministic concept, you can not explain it with a deterministic theory. You can see this in any work of thermodynamics, entropy is an ad hoc concept, it doesn't follow from the basic equations of Newton or any other basic equations who are time-symmetrical.
What seems to have happened to the universe, is that it started out in a very homogeneous, equalized state. Something disturbed that state, and touched off a cascade of chain reactions that, at first, destabilized the universe even further (by some kind of inertia, apparently) -- but the universe has since been on a trajectory toward maximizing its homogeneity.
again you are using indeterministic language : something disturbed that state. This something cannot be expained deterministically because it has no direct cause !
Now, given all that, it should be clear that a deterministic universe constrained toward equalizing disorder will not cycle -- for any true cycle would involve a reversal of the flow of disorder, which is kind of like creating a perpetual motion machine.
Given all that anything can follow since you contradicted yourself time and time again.
Then what is an interval? What is a metric? What makes for relationships such as in-between vs. outside? What is it that defines such properties as in-a-plane, vs. out-of-plane? Don't tell me we made it all up, because I'll slap you upside the head every time you put one foot in front of the other.
A metric (I assume you are talking about the g_{\mu\nu} of relativity) my dear Boris is something that is totally coordinate independent ! That was precisely the reason why Einstein used it in his relativity theory since any pinning to a certain coordinate system would have been fatal to the theory he was developing.
For the rest I refer you to what Crisp has said. And hope you won't slap him on the head for it ;)
I hate the direction this is taking, but I'm afraid it's back to the old 2+2 debate. You would agree, wouldn't you, that 2+2=4 is true not because we define it that way, but because we observe it that way? Of course, we could always define anything we want to be "true" by virtue of its definition; however applied mathematics is true by virtue of more than merely definition -- it is true by virtue of reflecting the observed properties of our world.
I'm afraid to say that we indeed defined 2+2 to be 4 since there are algebra's in which 2+2 equals zero and they are also perfectly consistent !
We have to resort to observation to choose the correct algebra that confirms with our universe. But this means that algebra is something far more general then the universe we live in, and certainly that mathematics is something far more general. It could be that there are several possible ways to describe our universe who are all totally consistent but are utterly different from each other. Our way is this specific type of algebra. Actually it is becoming more and more a trend to use geometry in stead of algebra to talk about the fundamental interactions, see String Theory.
Hence, it is a fundamental fallacy to regard any abstract mathematical model as a basic, irreducible explanation of any physical system. (Lest there be any mistake, this is indeed a direct assault on the Copenhagen philosophy.) Whenever mathematics is applied to model physical systems, it represents real objects and real properties.
Here I already have a counter example : when quantum mechanics was develloped in the twenties there were two distinct ways to tacle the problem : one was the wavemechanics of Schrödinger that involved a wave function, the other was the matrix mechanics of Heisenberg that involved non-commutable matrices. It took two year before it was realised that the two views were actually complementary, this was shown by Dirac and he made a third way of looking at quantummechanics: the bracet notations.
So you see that the mathematics aren't fundamental at all but are simply a language with different dialects that can talk about the same thing independently from each other.
I can if I realize that the global reference frame is not accessible (at least not easily) through electromagnetic phenomena -- because such phenomena always occur relative to one another.
What is this that you have against electromagnetism ? Besides all other forces are found based on this fundamental assumption that global symmetries need to be locallised in order to make them free of global referential frames, this is what gauge theory is all about !
I can if I merely restrict time from going backward. I can still talk about differentials in rate of events. As for metric distortions, I would like to ask you what it is you think that embodies the instantaneous metric at any point in "spacetime"? For that matter (and yet again), what is it that our concept of "spacetime" represents; what is its fundamental nature?
This going backward of time is merly a freak solution of the fundamental equations being time symmetric and will be taken care of in due time. What you are reffering to as 'rate' is exactly the same as 'time' there is no differentiation of rates if there is no differentiation of times.
What is spacetime ? Aha, actually I don't have the foggiest idea but what could come close to it could be this. I think what we call spacetime is the form and shape of the GUT-field of which all forces and particles come. Why does it has this specific amount of dimensions and shape ? Because it is the only possible one that agrees with gauge theory and renormalisation of this theory. You can get a feeling of this with String theory.
I cannot think of ways to form quanta from continuous substrates. In fact, the quantum mechanics' mixture of quanta (essentially integer arithmetic) with continuous fields (real number arithmetic) has always struck me as a grotesque amalgam -- a hack, at best.
Not at all Boris, the reason why continuous substrates become quantised is because they are waves ! Waves who are bound can only exist as an integral times their ground wave. Free wave are contiuous again, that is why photons come in any possible wavelenght and free electrons can have any possible energy. Once bound in an atom, their wavenature restricts them to a certain amount of energy states.
Point is, the "exact" constants, such as PI, defined by our mathematics are in reality not exact; their precision only goes as far as the resolution of the fundamental structure. It is only because large-scale objects are composed of such fine and many discrete building blocks, that we perceive continuity -- unless, that is, we begin to probe reality at quantum resolution. My claim is that in turn, any "continuity" we still observe at quantum scale turns into complete discreteness at the fine structure scale.
First of all, you are contradicting yourself again when you said that mathematics is something that we 'observe', if there is no such thing as a perfect circle in nature how are we to make a math with perfect circles ?
Besides I'm afraid gauge theory requires a continuous symmetry for it to produce photons and gravitons and gluons and W and Z bosons. So by by discrete theory.
? Here is my question again: why is right-handedness a property of the basic obsevables??
Yes, let's tacle this once and for all.
First of all we are talking about magnetism and electrostatic force which are not the fundamental forces. Magnetism is actually the rotor of the underlying Vector field : \nabla \times \vec{A} (I hope this \Latex notation makes any sense to you, if it doesn't \nabla is the sign used for taking the gradiant : \nabla f(\vec{r}) = \partial{f}/\partial{x}\vec{e}_x + \partial{f}/\partial{y}\vec{e}_y + \partial{f}/\partial{y}\vec{e}_y) and the electrostatic field is the gradient of the underlying scalair field plus the time derivative of the vectorfield.
\vec{E} = \nabla \phi - 1/c\partial{\vec{A}}/\partial{t}. So you see that the righthandedness that you are talking about finds its origan in the sign of the vectorfield and the scalair field.
Crisp is very much right when he says that a vectorpoduct isn't actually a vector at all, it is a pseudovector (also called an axial vector). This means that under parity transformations (this is the mirror transformation that Crisp was talking about) the pseudovector keeps his sign while the vector reverses it. This means that the magnetic field actually is a pseudovectorfield while the electric field a real vectorfield is. This is the reason why there is a fundamental righthandedness for the magnetic field because it is invariant under mirror transformations !
So thank you Crisp for finally pointing this out to us. :)
About your posts :
What does it take for you to realise that something can be incomplete deterministic and give a perfectly satisfying explanation at the same time...
I am begging for an example here.
Ok, let's take the wave nature of elementary particles, as I explained above it gives a perfect explanation of how an otherwise continuous substrate can give rise to quantised energy levels. This explanation requires nature to be indeterminsitic or rather : incomplete deterministic.
What this means is : if I postualte strict determinism as undertlying logic of the universe I can't explain quantisation, if I postulate incomplete determinism, I can expain it. Take your pick I should say.
Isn't this exactly what determinism is fundamentally all about ? Whether you regard determinism as a 1-1 causilty or an "underlying mechanism" (which are equivalent btw), it all comes down to one thing: being able to exactly predict how a system evolves once initial parameters are known.
No Crisp, as Boris already pointed out a deterministic system doesn't exhaust all its possiblities. If you propose a probability distribution as fundamental object then all the possiblities are exhausted by that, they will all have a certain probability.
Wow, this thread is steaming ! I love it ! :D
------------------
I err, therefore I exist !
Hi Plato, Boris, et al.
Phew, time to catch up with you guys; spent the last week preparing a presentation I had to give today (and rest assured, talking to 20 professors that know things way better than you is not an easy challenge ;).
Now for your post, Plato:
You should better use the term 'energy' in this context. But Boris, entropy is not a deterministic concept, you can not explain it with a deterministic theory. You can see this in any work of thermodynamics, entropy is an ad hoc concept, it doesn't follow from the basic equations of Newton or any other basic equations who are time-symmetrical.
Okay, thermodynamics is a very tricky subject because it involves a mixture of both deterministic and indeterministic reasonings. I agree when you say that all books on thermodynamics postulate the existance of entropy as the second law of thermodynamics, but most books also tell a little story about why entropy is necessary (and that's the "we cannot know all parameters for all 10^30 particles so we work statistically" explanation) and this is where the indeterministic view comes in. The underlying idea is deterministic however, in the way that in principle you could know all the 10^30 equations of state, but because it is inpractical, you use entropy and distributions.
again you are using indeterministic language : something disturbed that state. This something cannot be expained deterministically because it has no direct cause !
And why wouldn't it have a direct cause ?
So thank you Crisp for finally pointing this out to us.
I always liked math ;)
if I postualte strict determinism as undertlying logic of the universe I can't explain quantisation, if I postulate incomplete determinism, I can expain it. Take your pick I should say.
...
......
...
Okay....
...
I think you pretty much got me here ;). All of the sudden the idea of incomplete indeterminism sounds much more appealing :).
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
conseil
06-09-00, 04:21 PM
Following the discussion in this thread, I have to state I agree with Plato.
The argument of the decaying atom is indeed a good one here. Presently we must accept that 10 identical (to the best of our efforts) atoms can decay at different times, but that the probabilities always are correct. Saying there is still something we didn't discover yet is cheap. The theory we have now suffices. If there is more, good thing, but for now, that's a believe.
Science is not about believing.
About the beginning of the universe and the necessety of a cause that disturbed the initial state. Don't worry, off course there will be a cause, and science does it best to discover that. What Plato wants to show (I think), is that when we find the cause, we will also find that that cause could lead to a different outcome. And who knows, perhaps the probability for the outcome we had, is an almost centainty (a delta function as Plato calls it).
About the sidethread of the human brain. I also don't think it's a Turing Machine. It also works with probabilities (and I saw this in the course AI, part Neural Networks).
The way to make it animated (alive) is that we also have a system to evaluate the probabilities, and to apply feedback, so that the action with the biggest probability off success is pursued. So we don't just wait till things happen to us. We work out different threads (subconsciously), and evaluate this with a goal we set us to do. Since we don't know beforehand if one of the threads will lead to a way out of a certain situation, we can't predict if a person can solve a certain problem (although we are often capable of guessing the goal, based on passed actions).
My personal conclusion of this thread :
1/if one cause/start state can lead to different effects, then the world is indeterministic. Present experimental proof, leads me to believe this is the case.
2/if I can influence the process leading to the effect, and evaluate beforehand the different probabilities, I can choice the one best to my liking to follow. I still don't have certainty, but I have the choice of the functions with the biggest probability. In short, I am a free man.
Hi Conseil,
The argument of the decaying atom is indeed a good one here. Presently we must accept that 10 identical (to the best of our efforts) atoms can decay at different times, but that the probabilities always are correct. Saying there is still something we didn't discover yet is cheap. The theory we have now suffices.
Even though I now consider myself a fallen angel (sorry Boris, Plato got to me with his energy-discretization), I still cannot be satisfied with the decaying nucleus answer presented here - if we cannot predict when the nucleus will decay, or at least explain why the decay occurs (what internal cause leads to this) then our theories are still flawed. I've said this before, but now I believe that the mechanism behind it doesn't have to be deterministic per se. Finding the exact cause is important however.
Saying that there is something that hasn't been discovered yet is not cheap. It's the question that drives science. Denying that there are still things out there to be discovered is wrong IMHO; Einstein was right when he said that the more he knew, the more he was realizing that he in fact knew nothing.
If there is more, good thing, but for now, that's a believe. Science is not about believing.
I beg to differ. Science is a belief just like any other. Take away the belief in a few postulates and all theories we have melt away. Even experimentalists have to believe in their empirical laws, so I'd rather say that the whole of science is about rational believing.
Anyway, welcome to the board conseil :).
Bye!
Crisp
------------------
"The best thing you can become in life is yourself" -- M. Eyskens.
Hello Conseil,
thanks for the backup here. However there are some minor points I would like to clear up :
What Plato wants to show (I think), is that when we find the cause, we will also find that that cause could lead to a different outcome. And who knows, perhaps the probability for the outcome we had, is an almost centainty (a delta function as Plato calls it).
Yes, that is what I want to say : the same cause (e.g. the instability of the nothing) might lead to different outcomes. However I don't think that the probability would be a deltafunction. This would mean that there would be high restrictions on the initial conditions of our universe. For the moment I don't quite see where they would come from...
Crisp,
Let's see if I can make you fall a little bit further :D
I still cannot be satisfied with the decaying nucleus answer presented here - if we cannot predict when the nucleus will decay, or at least explain why the decay occurs (what internal cause leads to this) then our theories are still flawed. I've said this before, but now I believe that the mechanism behind it doesn't have to be deterministic per se. Finding the exact cause is important however.
Ok, let's look at the nucleus for a while. First of all, I don't know if you have seen any nuclear models but they actually very much resemble the models we have of atoms. They also have magical numbers of protons and neutrons where the nucleus is exceptionally stable (this means that the internal energy shows a minimum, but you probably knew that...) and they have 'orbitals' that can be filled with neutrons or protons. So we might as well look at decay of any kind of quantum system.
You probably also know that the Heisenberg uncertainty principle comes in two variants : the one which couples variations in impuls with variations in place and the one which couples variantions in time with variations in energy. This is quite easily understood if you look at it through special relativity eyes then the two relations become two aspects of the same four-vector relation.
What does the second relation mean ? It finds its meaning in decay and absorption reactions.
What does it tell us of stable systems ? A stable system would mean no energy variation, this means an infinite time variation or in other words we don't know or have no way of knowing when this system was created or when it will ever decay. This already shows the way to the fundamental interchangebility of quantumsystems with the same energy.
What does it mean for an unstable system ? Here we have a way to predict how long this system will live, to a certain degree of course. We can calculate the exact time it takes for the system to have a fifty percent chance to decay (or any other chance to that respect). The reason we are able to do this is because we know the cause of the instability, this could be for example in the case of Carbon 14, to have two neutrons to many. We can calculate how much energy these neutrons have in their orbitals and thus how much energy will be released at least when the nucleus decays by converting one of the neutrons into a proton and sending out an electron and anti-neutrino in the process.
Boris,
I have been reading some sites that talk about String theory : it doesn't look good at all for determinists :cool:
It appears that they even have an additional uncertainty : namely one that prevents them to know the exact nature of spacetime itself ! By, by discrete grid of which everything is build...
------------------
I err, therefore I exist !
Patterns, Design, and Physical Laws
A computer program will behave in exactly the same way at any time on any computer, given the same initial state. A software program is an example of a "pattern". The program may be copied. Two copies of the program will behave exactly the same way on two different computers even though the two computers, on which the program copies run, are made up of completely different atoms from one another.
Because the computer program is a pattern, it could be translated into an entirely different programming language and run on an entirely new type of computer. The computers are patterns as well. The pattern called "computer" and the pattern called "program" have a degree of independence from the stuff of which they are made. At the physical level, the atoms, and electrons, and the energy states are absolutely 100% different on both machines and both "copies" of the "same" program, yet the programs behave in exactly the same way on the "design" level!
Ultimately, the computer and the program that runs on it are subject to the pre-determined laws at the physical level, but the patterns at the design level are subject to a much stronger force - that imposed by the pattern itself. Even though the atoms, the initial state and everything about the two computers and the two programs can be absolutely 100% different in space, time, behavior, initial state, molecular structure, elements, and on and on..., the pattern manages to "overrule" the pre-determined physical state that the computer and the program will be in at the start and the end of the running at end of the program. We are not even concerned of the "physical" state of the pattern, only the "design" state of the pattern.
Patterns are at least somewhat independent of the stuff of which they are made. A boat is a pattern. If it has several parts replaced on it, as the parts wear out, it is still recognized as the same boat. A person is a pattern with atoms and cells that are constantly changing.
Similar to the program pattern, identical twins are born with identical copies of a DNA pattern, but each copy is obviously made up of separate molecules. The twins rapidly form separate identities because their initial conditions and environments are different at both the physical and the pattern level.
Unlike boats, DNA, people, computers, and Turing machines all are patterns that contain a type of memory and take input from the outside environment in the world in which they exist. DNA and people are different from computers and Turing machines, largely due to their relative complexity, but at least partially because they are subject to both physical and pattern states. Physical objects, independent of the person or the DNA may change their respective pattern behavior in unpredictable ways. Unless pre-programmed in advance, to accept inputs, for example, an ordinary software program will ignore external events.
Although, ultimately "it is all physical", the white blood cell reacts to the germ that it "detects" in the blood stream, because it is "programmed" by the DNA to seek and destroy germs, not merely clumps of amino acids, but the special pattern we may call a "germ".
DNA mutates in a random way due to being struck by various particles. These mutations are the physical mechanisms by which Evolution occurs. Mother Nature would not get very far by merely following low-level physical laws. Random change must be augmented by a Design mechanism - the Pattern of Natural Selection which is used to select the most "useful" designs for replication, and to eliminate the "bad" designs. Natural Selection is a very slow process, because it is so closely linked to the natural physical level. That is why relatively simplistic life forms do not have many degrees of freedom. However, as the patterns (life forms), become more and more complex, with patterns layering upon other layers of patterns, they gain more and more freedom from their physical makeup. Each pattern layer is subject to the new laws of the pattern "designs" of the layers "below" allowing a slightly higher degree of freedom from the underlying physical layer.
The computer program "if" statement "reacts" to the value (pattern, design) of "true" or "false", and does not give one hoot about the makeup of the computer or how the "true" or "false" is ultimately represented at the physical level. An "if" statement embedded inside a computer program follows rules that are designed into the programming language. The computer program may be of the sort, such as the Java programming language, that is interpreted by a virtual machine - yet another program. The virtual machine is said to run "on top of" the computer operating system. Eventually, these multiple layers of programs (patterns) get converted into the machine language that the Central Processing Unit (CPU) "understands". The CPU, in turn, is made up of patterns of circuits. The circuits are made up of a complex pattern of logical “NAND”, “XOR” and “NOT” gates, and are manufactured out of silicon and various other elements, consisting of atoms, and powered by electricity.
Each layer outlined above, from the bottom physical layers, to the top software layers, have room for multiple design or pattern variations in their makeup. As long as each pattern layer is designed in such a way as to produce the same outputs and accept the same inputs that are “expected” by the layers immediately above and below it, the design variations will not affect the state of the program of interest at the top layer. In general, the higher the level in the pattern layers, the higher the degrees of freedom one has in the design of that level. The original program could be written in several different ways, and still express identical results to the original.
A baseball player, consisting of many more complex layers than a computer program, may decide to move out of the way of the ball rapidly flying towards his face, because the ball is going to smack him in the face and it will hurt. The physical state of the ball is of no immediate interest. It could be any baseball at any time in any space - it is the "ball" and "face" and "pain" patterns that are the important pieces of information stored somewhere in the baseball player's brain. It could be any baseball player playing on any baseball team. It is not inevitable that the player will be hit by the ball or that player will avoid the ball.
The baseball player’s conscious level is built upon countless pattern-based "design" layers which allows for a degree of freedom allowing for the avoidance of the "inevitability" of being struck by the ball. The baseball player’s conscious mind is much more influenced both by the patterns it is processing, and the patterns doing the processing, than by the physical stuff that the player’s brain is made of.
Ultimately, the physical structures of the atoms involved do matter. The physical laws do determine the direction, speed, and force of impact of the ball. The brain is physically made out of atoms, but the baseball player does not care or think about those things. The player is considering the patterns (and avoiding pain).
Free Will and Determinism are not mutually exclusive. Indeed, an agent "pattern", with a memory and feedback from the external world can make predictions better in a fully deterministic universe than it could in a non-deterministic universe. Calculation can be made by that agent, to avoid dangers, seek energy sources, improve its local environment, self-replicate, communicate (via yet another set of patterns following rules) with other similarly-patterned agents, and so on.
Above, I mentioned that “patterns at the design level are subject to a much stronger force - that imposed by the pattern itself”. “A much stronger influence" is a more accurate phrase. Weaker forces seem to have stronger influences at macroscopic levels than do the strong forces.
I am no expert in physics, so some statements may not be completely accurate. Hopefully, the overall concepts will be clear:
At the sub-atomic level, we see that there seems to be a non-deterministic quantum state "ruling" this "lowest level of all worlds" world - the center of the onion. However, it is masked by a more deterministic, atomic-level "pattern" one, or just a few levels above it.
The Neutrons and Protons consist of sets of 3 quarks each, held by the strong nuclear force. A residual force holds the nucleus together. The weak nuclear force works at a larger distance but is obviously weaker. The Electro-magnetic force controls electrons, with the residual binging atoms to create molecules.
Already, at these lower pattern levels, determinism seems to overcome the quantum effect. The larger the pattern, the more reliable and useful they become. On my way to work, I do not have to hunt for the local Starbucks, where I get my coffee for my long trek to work in the morning ;)
Gravity is a force that is so weak, that scientist are just now getting the point where it can be measured at distances down to the millimeter. I have heard that gravity is 5-10 orders of magnitude weaker than the electro-magnetic force, yet it has a dominant influence over ordinary matter! As I sit here at my computer desk, I can very much feel gravity holding me down on my chair. The patterns of solar systems and galaxies are not “interested” in the stronger forces. Still larger patterns are dominated by Dark Energy (from the vacuum of space?) Is this because the entire Universe is the largest and greatest pattern?
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.