Criticism of Determinism and it's relation to the Many Worlds Interpretation

Recently in response to a paradoxical question posed by Edwin Schrodinger, modern physicists have come up with a rather creative theory to explain a challenge to the coherence of the Quantum Mechanics field of physics, yet apparently put absolutely no thought into the practical application of it. While the MWI provides a simple and comprehensive solution to the problem of Schrodinger's cat at first glance, it still has utterly failed (at least in my eyes) to reconcile itself with determinism. The Many Worlds Interpretation relies entirely on a completely contradictory "deterministic" system that branches into separate universes at the appearance of an event in which multiple outcomes may exist. However adhering to the deterministic principle, it is completely impossible for this branch to occur, due to the fact that only one outcome is ever possible in a deterministic system. In a deterministic system the entirety of the preceeding parts of the system determine the existence and behavior of the system in the future. If this event were to truly branch according to MWI, then it would regressively have to change the entirety of events leading up to it, effectively changing the universe and causing it to be completely independent and never actually associated with the original universe to begin with. Essentially in order for a different possibility to occur, the conditions of the entire universe would have to be modified to allow for it, making it completely impossible for this event to have been possible in the other dimension. Furthermore, all separate possibilities that are envisioned by this theory are unable to interact in any way due to their inherent seperation in reality.

am i missing something or is it really this obvious

I agree with you. The many worlds interpretation doesn't return determinism to physics. Quantum mechanics appears to be non-deterministic, no matter how you look at it.

And, as some have already guessed, the Relativity foundation of Minkowski four space, with, if I may point it out, its total reliance upon the absolute determinance of the ( time ) world line to connect adjacent three space universal moments, places Relativity and Quantum Physics in a situation analgous to a knife fight in a phone booth.

Relativity is in its intrinsic nature totally deterministic, and Quantum Physics is in its intrinsic nature nature totally non-deterministic.

Quantum physics isn't totally non-deterministic. Totally non-deterministic means random. Quantum physics is not random, or we wouldn't be able to predict anything about quantum systems.

I agree that relativity is deterministic.

James R: The following does not seem valid.Quantum physics isn't totally non-deterministic. Totally non-deterministic means random. Quantum physics is not random, or we wouldn't be able to predict anything about quantum systems.We can make very accurate predictions in spite of the random behavior of quantum systems because of the huge number of quantum entities involved in quantum processes.

As a simple illustration, consider radioactive decay. This is a random process conforming to Poisson (or maybe binomial) statistics. A small amount of a radioactive substance has about 10²⁴ atoms. While we cannot predict which atoms will decay, we can accurately predict how many will decay in a particular time interval. This allows us to build very accurate clocks based on radioactive decay, even though we have good reason to believe that it is a random and non-deterministic process.

Dinosaur:

We can write down the wavefunction for many quantum systems. It is not random. Therefore, quantum physics is not random.

End of argument.

Dinosaur:

We can write down the wavefunction for many quantum systems. It is not random. Therefore, quantum physics is not random.

End of argument.

Because WE CAN TAKE IT FROM YOU.

I can write down: "JamesR is a nutbag.".

Does my ability to write it down make it undeniably true?

James R: Correct me if I have some terrible misunderstanding of the wave function. I did not think it gave precise positions. I thought it gave a probability for each possible position. I did not think it predicted where one would find a particular quantum entity.

If it does not accurately predict a reasonably precise position (as do Newton's gravitational equations), then it can hardly be called deterministic. If (as I believe) it merely provides probabilities for various possible positions, then it describes probabilistic (Id est: random) processes.

Surely radioactive decay statistics strongly support the notion of a random process. Without knowledge we do not currently possess, radioactive decay cannot reasonably be considered anything but a random process. Furthermore, it is my very reasonable belief that further knowledge of some mechanism controlling radioactive decay will merely push the randomness down a level rather than providing a truly deterministic explanation.

BTW: Schroedinger was on a quest for classical deterministic equations. He, like Einstein, was not satisified with nondeterministic probabilistic descriptions of the quantum world. When he finally developed his wave eqution, he said something like the following.If I had known how it was going to turn out, I would have become a chemist or biologist instead of a physicist.His thought expeirment about the cat was an attempt to argue against the Bohr/Heisenberg view of quantum phenomena.

I agree with you. The many worlds interpretation doesn't return determinism to physics. Quantum mechanics appears to be non-deterministic, no matter how you look at it.

JamesR needs to make up their minds about whether they believe Quantum Physics is deterministic or non-deterministic.

To be repetetively and even doubly redundant: Relativity is absolutely positively deterministic, because of its basis of Minkowski four space in which every three space (snapshot of the ) universe is connected by the four space (time) world line. Everything which can happen has already happened and is either in the past or present or future relative to the instantaneous position of the world line.

And, according to Quantum physics, absolutely positively nothing IN SPECIFIC PARTICULAR can be determined.

Anyone who does not really understand these points about either Relativity or Quantum Physics has not been reading their physics literature like any good little boy should have been doing.

End of discussion.

Dinosaur,

James R: Correct me if I have some terrible misunderstanding of the wave function. I did not think it gave precise positions. I thought it gave a probability for each possible position. I did not think it predicted where one would find a particular quantum entity.

If it does not accurately predict a reasonably precise position (as do Newton's gravitational equations), then it can hardly be called deterministic.

I think you're misunderstanding what determinism means. Determinism means that if the state of a system is given at time t, then the state at time t+dt can be deduced from a set of equations. That is, we know how the state evolves with time.

In the case of quantum mechanics, wavefunctions evolve according to the Schrodinger equation. That evolution is totally deterministic. But, here's the catch: whenever the wavefunction "collapses" (for example, when a measurement is made on a quantum system), the state evolves non-deterministically, changing to one of the eigenstates of the system. However, even this process is not totally random, since the probability of finding the system in one or other of the eigenstates following a collapse is predictable.

My point is not that there is no randomness in quantum mechanics. I am simply pointing out that claims that quantum mechanics is totally random and non-deterministic are false.

It's a reasonably simple point and uncontroversial point, which I fear is being blown out of proportion.

Surely radioactive decay statistics strongly support the notion of a random process. Without knowledge we do not currently possess, radioactive decay cannot reasonably be considered anything but a random process.

But it is not totally random. The probability of decay of any atom in a given time frame is constant and known.

CANGAS:


JamesR needs to make up their minds about whether they believe Quantum Physics is deterministic or non-deterministic.

This isn't an either-or choice. Some aspects of quantum mechanics are deterministic; others are not. It's not my fault that you know as little about quantum physics as you know about relativity.

To be repetetively and even doubly redundant: Relativity is absolutely positively deterministic, because of its basis of Minkowski four space in which every three space (snapshot of the ) universe is connected by the four space (time) world line. Everything which can happen has already happened and is either in the past or present or future relative to the instantaneous position of the world line.

I agree.

And, according to Quantum physics, absolutely positively nothing IN SPECIFIC PARTICULAR can be determined.

Wrong. Go educate yourself. Start by reading my comments to Dinosaur, above.

Dinosaur,


But it is not totally random. The probability of decay of any atom in a given time frame is constant and known.



The probability of a random function(for example random numbers function on a computer) generating each possible solution is well known. It doesn't make the function any less random.

The fact that we found the probability tables for each event implies that we DO accept the events are either random or we do not know HOW they are not random.

James R, neither of us here really invented this view on quantum physics, it was thought of by Einstein who did provide some truly deterministic theories. So, with respect to him, you should realize that we too don't have to "embrace" quantum physics with a happy face. We can accept it provides some worthy and accurate predictions, but we do not have to regard it as the 'end of story' theory when it comes to space-energy fundamentals.

Dinosaur,



I think you're misunderstanding what determinism means. Determinism means that if the state of a system is given at time t, then the state at time t+dt can be deduced from a set of equations. That is, we know how the state evolves with time.

In the case of quantum mechanics, wavefunctions evolve according to the Schrodinger equation. That evolution is totally deterministic. But, here's the catch: whenever the wavefunction "collapses" (for example, when a measurement is made on a quantum system), the state evolves non-deterministically, changing to one of the eigenstates of the system. However, even this process is not totally random, since the probability of finding the system in one or other of the eigenstates following a collapse is predictable.

My point is not that there is no randomness in quantum mechanics. I am simply pointing out that claims that quantum mechanics is totally random and non-deterministic are false.

It's a reasonably simple point and uncontroversial point, which I fear is being blown out of proportion.



But it is not totally random. The probability of decay of any atom in a given time frame is constant and known.

CANGAS:




This isn't an either-or choice. Some aspects of quantum mechanics are deterministic; others are not. It's not my fault that you know as little about quantum physics as you know about relativity.



I agree.



Wrong. Go educate yourself. Start by reading my comments to Dinosaur, above.

If JanesR had ever read a science publication after about 1927 he would understand that Heisenberg uncertainty prevents any specific information about any spefic particle to be DETERMINED.

I am growing very weary of having someone who has not read a physics book for many decades tell me that the claims of the Standard Model are wrong but does not ever present any whiff of proof.

If Quantum Physics proves to you, JanesR, that The quantum view of reality is exactly determinable, GIVE US SOME QUOTES AND REFERENCES.

CANGAS:

If Quantum Physics proves to you, JanesR, that The quantum view of reality is exactly determinable, GIVE US SOME QUOTES AND REFERENCES.

Your continual deliberate misconstruction of what I write is getting wearisome.

I have been very clear on which parts of quantum theory are deterministic and which are not. I have never once claimed that all of quantum mechanics is deterministic - either in this thread or anywhere else.

I have made the very simple and obvious point that quantum mechanics is not totally random.

Your personal comments and insinuations are water off a duck's back. Here you are, a complete nobody, telling an employed physicist that he doesn't know physics.

Stick to what you're good at, CANGAS. You probably have skills in some area of other, but your expertise sure ain't physics.

CANGAS:



Your continual deliberate misconstruction of what I write is getting wearisome.

I have been very clear on which parts of quantum theory are deterministic and which are not. I have never once claimed that all of quantum mechanics is deterministic - either in this thread or anywhere else.

I have made the very simple and obvious point that quantum mechanics is not totally random.

Your personal comments and insinuations are water off a duck's back. Here you are, a complete nobody, telling an employed physicist that he doesn't know physics.

Stick to what you're good at, CANGAS. You probably have skills in some area of other, but your expertise sure ain't physics.


It is the very height of entertainment for me, to read that you call me a nobody whereas you have no personal knowledge of me and my present formal credentials or employment. Perhaps you think are clairvoyant?

There are physicists who are employed flipping burgers and/or cleaning toilets ( not that there's anything wrong with that ), so your proud proclamation of being employed means absolutely nothing to me. We are all happy that you are earning your own living(?) and that you have pride in what you are doing.

The issue which you have tried to obscure with these several Red Herrings, is that you have claimed that the Quantum Physics view of reality is not completely non-determinate, ( in contravention to Special Relativity, which is completely determinate. ).

There are pupils in grade school who understand that Heisenberg's uncertainty principle, published in 1927, claims blatantly that, in terms of Quantum Physics, the position of every particle in the universe is absolutely non-determinate: it cannot in principle possibly be determined.

In contrast, Einstein Relativities, based inextricably upon Minkowski 4 space and also fully honoring the classical traditions of Newtonian physics and relativity, treats the position of every particle in the universe as not only being exactly defineable but as being absolutely defined in actual fact within each Minkowski 3 space which is connected by the world line.

JanesR; I cannot, if I try, insult you any more than your own posts do.

CANGAS:

It is the very height of entertainment for me, to read that you call me a nobody whereas you have no personal knowledge of me and my present formal credentials or employment. Perhaps you think are clairvoyant?

It is sufficient that I can tell from your posts that you are not a physicist.

There are physicists who are employed flipping burgers and/or cleaning toilets ( not that there's anything wrong with that ), so your proud proclamation of being employed means absolutely nothing to me. We are all happy that you are earning your own living(?) and that you have pride in what you are doing.

Thankyou. That is good to hear.

The issue which you have tried to obscure with these several Red Herrings, is that you have claimed that the Quantum Physics view of reality is not completely non-determinate, ( in contravention to Special Relativity, which is completely determinate. ).

I have not tried to obscure this. On the contrary, I have repeated it over and over again, very clearly and succinctly, because you seemingly failed to understand the point the first few times I made it.

There are pupils in grade school who understand that Heisenberg's uncertainty principle, published in 1927, claims blatantly that, in terms of Quantum Physics, the position of every particle in the universe is absolutely non-determinate: it cannot in principle possibly be determined.

That is not what Heisenberg's uncertainty principle says. You need to do some basic study.

In contrast, Einstein Relativities, based inextricably upon Minkowski 4 space and also fully honoring the classical traditions of Newtonian physics and relativity, treats the position of every particle in the universe as not only being exactly defineable but as being absolutely defined in actual fact within each Minkowski 3 space which is connected by the world line.

I agree.

You're not advancing the discussion at all with your posts. Every statement you make that attempts to refute rather than agree with something I have written turns out at the slightest examination to be patently incorrect.

James R: Relating to radioactive decay you posted the following.But it is not totally random. The probability of decay of any atom in a given time frame is constant and known.The difference between random and totally random escapes me.

To me random relates to processes associated with statistical data. Radioactive decay conforms quite well to this view.If the number of decays is recorded for each half life, radioactive decay can be very accurately modeled by flipping a true coin for each atom. Heads, decay; Tails, no decay. This model works for one atom as well as for all the atoms in several kilograms (perhaps 10²⁴ atoms). I think this is binomial distribution stastistics.

For time intervals much smaller than a half life, I think the decay is well modeled by Poisson statistics, also a well known probability distribution.The half life is used to describe the decay rate because there is no whole life, due to the process being random rather than deterministic.

What does totally random mean? to me it conjures up dice for which the numbers get changed between throws without allowing the numbers to be known in advance, making it impossible to determine any probabilities. For example.First throw with ordinary dice: 1 to 6 on the six faces. Second throw with only three numbers on each die (opposite faces have same value). Third throw with 25 on each face of one die and 22 on each face of the other.You get the picture in my mind. Is that an example of totally random?

Are throws of ordinary dice slightly deterministic because I know the probabilities associated with each total? Does this knowledge make the process not random?

BTW: I find it fascinating that the classical world of our senses seems predictable and deterministic even though it is built on a quantum world governed by probability rather than by deterministic laws.

Statistics and probability are often referred to as the laws of large numbers. This is due to the fact that the more trials, the closer the statistics match the predicted probabilities. Our classical world is built on quantum processes usually involving huge numbers of particles. 10²² is a small number of particles in that quantum world. A small glass of water consists of perhaps 10²⁴ or more molecules. Probabilistic laws applied to huge numbers of quantum entities allow for accurate predictions.

Even though radioactive decay is a probabilistic process, it can be used as the basis for very accurate clocks, which seem deterministic in nature.

Dinosaur:

"Totally random" would mean that we could not say anything about the state of a system at time t+dt knowing the state at time t.

With radioactive decay, we can give a probability that there will have been no decay in time interval dt, and a probability that a decay will have happened after a time interval dt. Thus, radioactive decay is not "totally random".

As it turns out, throws of coins or dice are not just "slightly deterministic", but almost "totally deterministic". In principle, if we know the state of a coin before a toss, and the details of the toss itself (forces exerted on the coin during the toss), then we can predict with certainty what the outcome of the toss will be using known physical laws.

Our statistical treatment of coin tosses and dice rolls is necessary not because of indeterminacy but because of our lack of knowledge of all the relevant conditions prior to and during the toss.

Similarly, it has been suggested by some that the statistical nature of quantum mechanics may say more about our lack of knowledge of the system in question than about any actual inbuilt indeterminacy. In the quantum case, though, the problem is complicated by a number of factors. For example, experiments associated with Bell's inequalities appear to rule out so-called "hidden variable" theories in quantum physics.

If there physics laws are constant, no process can be totaly random. A totaly random process can occur only if the physics laws change totaly random.

If a process is totaly random, that means there is no finite number of measurements/data that can be taken to create a useful statistic to predict the process.
If you take 10^100000 measurements or results of a process and create a statistic, the next 10^10000 measurements would yield a totaly different statistic. No matter how large the number of measurments is used to create the statistic - it will never be able to predict the outcome of the forthcoming measurements.
In other words, as the number of measurements for creating a statistic is increased - the resulting statistics do not tend to unite at a single value.

Unlike statistics for throwing a coin where the statistical probability for each side tends to 50% as the number of tosses used to create the statistic is increased.