What is the cause of Radioactive Decay

Discussion in 'Physics & Math' started by RajeshTrivedi, Aug 7, 2017.

  1. Geon Registered Member

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    Wonderful - even more important than that if true, is the nature of falsifiability from the scientific method. Otherwise, a thing isn't a theory.
     
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  3. iceaura Valued Senior Member

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    So? I didn't mention falsifiability.
    You seem to have causality and falsifiability confused with each other. Is that why you think causality must be fundamental to science somehow, regardless of appearances - because you think falsifiability depends on it?
    Just say it: you can't name the cause of Darwinian evolution. You can't name the cause of the operations of the 2nd Law, either. And you would have trouble, had you attempted that simpler task I offered, naming the fundamental cause of a balloon popping when it does ("air pressure" is obviously derivative, as well as being partial).
     
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  5. Geon Registered Member

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    Oh you might not have but I am.

    You are arguing the wave function is random, I've corrected you on a number of things, such as, it is not a priori that a wave function need be random. I have corrected you, in thinking only probabilities are described by random systems. This is clearly rubbish in quantum mechanics where the wave function is completely deterministic, its only the collapse of a system that is sometimes considered random. Of course, this is even if collapse models are correct as understood from the Copenhagen interpretation.

    So yes, if you say a system is simply random, that doesn't answer anything and leaves nothing to be proven or falsified - actually to call something random is arguably lazy and bad science. That isn't science.
     
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  7. Geon Registered Member

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    I could name loads of things, but its like talking with a child when talking to you. You have to point out obvious assertions like ''there are many causes, but it's causal.''

    You're borderline moronic.
     
  8. iceaura Valued Senior Member

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    No, I'm not.
    I have explicitly and specifically stated that mathematical equations and the calculations involving them are not "random". Repeatedly. In direct and simple language.
    Then you are not addressing my post, which you quoted, but strawmanning instead.

    My impression is that you regard causality and falsifiability as interchangeable, as joined and coextensive attributes. I got that impression from your repeated substitution of one for the other, in your replies. You refuse to clarify or disabuse me of this impression.

    If that's how you're thinking, that error explains a lot.
    I doubt you will ever be able to name the, a, or any, cause of Darwinian evolution.

    As you attempt to create some kind of system of "causes" in pursuit of a useless causality, you will find yourself talking about a world of phenomena none of which themselves cause Darwinian evolution, no one of which is even necessary let alone sufficient, none of which predict, none of which are even correlated with it in any sense except probabilistic.

    There are many phenomena in the world for which people find cause/effect explanations very useful. Darwinian evolution is not one of them. The 2nd Law is not one of them. And so forth.

    Fundamental scientific theories, these. If you want a cause/effect explication or convenient heuristic for them, you will have to make some adjustments in what you regard as a "cause". And so the discomfort created by the intuitive impasse of QED and its Bell violations has longer and deeper roots than at first supposed.
     
    Last edited: Sep 4, 2017
  9. Beer w/Straw Transcendental Ignorance! Valued Senior Member

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    What's the 2nd law? I keep thinking thermodynamics.
     
  10. exchemist Valued Senior Member

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    That's what he means, I think.But I'm having trouble following the argument. The 2nd law of TD can be explained by the tendency of entropy to increase, which is turn is due to ("caused by"?) the operation of randomness in nature. Or something....

    But Geon is being a patronising tit......
     
  11. Geon Registered Member

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    The second law is a statement of both increasing entropy, and that more generally entropy is never negative... and yes, it may seem like I am being patronising... and it may very well be because the person I am talking to first claimed that probabilities in quantum mechanics are random... then from the last post, it seems he isn't saying the wave function is random... I mean... wtf is it? I have been having this conversation for days and I feel like he's an absolute troll.
     
  12. iceaura Valued Senior Member

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    When anyone capitalizes the term in a scientific context - "The 2nd Law" - that's what they're talking about.
    Hence my offering it as an example for Geon. It's not "causal", and it demonstrates that causality is not fundamental and underlying all of science.
    He is also wrong, which is more to the point.
     
  13. iceaura Valued Senior Member

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    It's you refusing to address - or even read, apparently - the posts you supposedly are responding to.
     
  14. exchemist Valued Senior Member

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    It is one thing to say the wave function is not random. Self-evidently it is not, being a mathematically exact representation of the state of the system, from which physical observables can be calculated by use of the appropriate QM operator.

    However that is not inconsistent with saying that QM predicts that individual measurements will contain a random element. This is obviously the case, seeing as the square modulus of the wave function is a probability density and that, due to the uncertainty principle, there are limits to the exactness with which observables can be defined and measured. To use the well known example, it is impossible to predict exactly the location at which a wave-particle will be found and the exact value for its momentum that will be measured. There is a random element to the results of each measurement, surely?

    You give the impression of looking for a fight with Iceaura about this, for some reason, which seems to me wholly unnecessary. Furthermore, I see no basis for you to patronise Iceaura, seeing as he or she has demonstrated - I think - a perfectly reasonable level of knowledge of the relevant physics.

    Is this disagreement about the semantics of "random", perhaps? Would you prefer "uncertainty" or some other expression indicating lack of exactitude?
     
  15. Geon Registered Member

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    190

    The problem is, though he has made similar statements along the line of --- ''its a priori in probability that it is generated randomly.''

    Where exactly is that a fundamental rule? Never in science, just because we lack for a better model to describe something, do we just sit back and say ''oh well, its all random isn't it?''

    Well no it isn't, as you pointed out and as I have been pointing out all along. It's the choice out of a selection, the collapse, the whatever-you-want-to-call-it, its this some people have speculated is random. Arguably, nothing is left to random acts in nature, there are real physical things going on that we are unaware of or haven't took into consideration.

    There should be no semantics over ''random'' --- we all know what it means. But when someone goes about talking about randomness as a priori of statistics and probability, it gives the wrong impression of quantum mechanics which is largely a statistical theory - because we know today, randomness is not a priori of nature - it's not even an axiom of the probability theories in physics, the random model at best, seen from a Copenhagen model is an interpretation of physics, not an axiom or priori.
     
  16. exchemist Valued Senior Member

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    Well I see what you are saying but I think you are taking a rather extreme view. In kinetic theory, do we not treat the motion of molecules as random? And in statistical thermodynamics do we not take this random motion to be what underlies the distribution of occupancy of energy levels that gives rise to thermodynamic properties?

    I have always thought statistical thermodynamics to be one of the all-time triumphs of physical science, in that it shows how order emerges quite naturally from chaotic motion, due to the operation of basic physical laws. Do you really see no randomness at work here? Or are you really more concerned about the application of the term to QM, rather than to Stat TD?
     
    Last edited: Sep 5, 2017
  17. Geon Registered Member

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    Not to my knowledge. How would you make it random? The evolution of a wave function is deterministic, its the choice from possibilities which fails to have a direct relationship to causal physics, but this is likely to be a lack of our understanding of the system - even using your example you think the motion of particles, (is random) and that as a statement is an extreme.

    There are limits on what we can precisely know - but that doesn't mean we can't know it a lot of the time. It's just that sometimes, physics acts like it follows random laws https://www.sciencenews.org/article/uncertainty-not-so-certain-after-all - this was actually something I brought up before, you must have missed it... either here or in the other thread. The ''randomness'' implied by the uncertainty principle, is actually not so random.
     
  18. Geon Registered Member

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    But again... its the quantum world, there's a lot of fuzz and corrections down there. If people think it truly is random without having a larger scope of these corrections we need, we're gonna get no where. Yes there are things we don't understand about quantum theory or don't have the answer, but I thinks its another to call it random just because we can't answer it.
     
  19. exchemist Valued Senior Member

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    I'm not talking about wave functions here, just Brownian motion.
     
  20. iceaura Valued Senior Member

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    Please don't put your illiterate misrepresentations of my posting in quotes, as if I had said any such stupid thing.

    And if you would stop basing your responses supposedly to me on such carelessness and error of your own, it would save both of us a lot of typing.
    And I have repeatedly pointed out to you that confusing determinism and causality is a mistake. It's an error. It's wrong. Stop doing that, and your thinking will clarify considerably.
    Nothing on this planet is more irrevocably, unstoppably, completely, and permanently determined than the long term outcome of random behavior governed by a probability distribution. You want something determined? Have it depend on the patterns generated by randomness.
    But that's not what anybody is doing. It's the knowledge of quantum behavior and theory, what we do know about it, that has led to some people assuming acausal generation - not the gaps, but the fills. The Bell violations, for example. The inability of causal explanations to account for observation without forcing discard of well-established and fundamental theory that has no other conflicts.

    And I have offered you at least one way out of the impasse you face: revise and broaden your intuitive comprehension of "probability", in line with the other revisions of intuition made possible by mathematical description over the centuries, by the workings of mathematical theory in demonstrating the possibilities of the real world.
     
    Last edited: Sep 5, 2017
  21. hansda Valued Senior Member

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    Consider a quantum particle. Consider no force is applied to this particle. How this particle should move? In a random direction? or, It will move in a direction following the Law of Inertia?
     
  22. exchemist Valued Senior Member

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    Neither, Hansda. Its behaviour will be described by a wave function and, because of Heisenberg's Uncertainty Principle, its position and momentum cannot both be exactly known. If we know its momentum exactly we do not know where in space it is, and if we know where in space it is we do not know its momentum. Or we can approximately know both, within limits.

    This means we cannot treat a quantum "particle" as a simple particle. It is a wave-particle and it requires quantum mechanics to predict its behaviour. So your question, based as it is on classical mechanics, poses a false antithesis. To follow the Law of Inertia (Newton's 1st Law), both momentum and position over time would be exactly predicted. We can't do that in such a case, due to the wave nature of matter.
     
  23. hansda Valued Senior Member

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    So, you mean the particle will not move randomly. You also mean that the particle will not follow the Law of Inertia. Is there any third option for the particle to move?

    Wave function is based on probability. Probability is based on random nature of motion. But you deny its random motion.

    Wave-particle and wave-function are different concepts.

    I am not asking about the momentum of a particle.
     

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