Is Physical Processes Governed by Chance?

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Discussion Overview

The discussion centers on whether physical processes, particularly radioactivity, are governed by chance or if there are deterministic causes underlying these phenomena. Participants explore the implications of quantum mechanics, statistical predictability, and the nature of atomic behavior, with a focus on theoretical and conceptual aspects.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants argue that radioactivity's statistical predictability suggests an underlying cause rather than mere chance.
  • Others assert that the inability to create a deterministic model for small-scale behavior indicates that such processes cannot be fully understood through deterministic frameworks.
  • A participant mentions that the concept of entropy in unstable uranium atoms implies a cause for radioactivity, but this is challenged as circular reasoning.
  • There is a discussion about quantum amplitudes and probabilities, with claims that these are fundamental to quantum mechanics and that no deeper deterministic explanation exists.
  • Some propose alternative theories, such as Bohm's "Implicate Order," which may provide order but lack predictive capability.
  • One participant suggests that "spontaneous" decays could be triggered by interactions with virtual particles, raising questions about the nature of decay and the role of wave properties in quantum mechanics.
  • Concerns are raised about the implications of rejecting quantum mechanics for the understanding of physical processes.

Areas of Agreement / Disagreement

Participants express a range of views, with no consensus on whether physical processes are governed by chance or deterministic causes. Disagreements persist regarding the interpretation of quantum mechanics and the implications for understanding radioactivity.

Contextual Notes

Participants highlight limitations in current models and the challenges of defining determinism in quantum systems. There are unresolved questions about the nature of interactions that lead to decay and the implications of quantum mechanics on determinism.

Hydr0matic
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I have to ask, is there any sensible reason to believe that physical processes, let's say radioactivity, is governed by chance ? Isn't that conclusion unwarranted ? I mean, the fact that radioactiveness is statistically predictable and depending on atomic structure, is a strong indicator that there's an actual cause for these seemingly random decays. And considering the probability that our atomic model is a true representation of physical reality, we can barely make qualified guesses about these kind of processes.

What do you think, is science in denial ?
 
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There are no ways to build a deterministic model of small-scale behavior in this universe. Period.

That a variable is 'statistically predictable' does not imply it has some deterministic cause at all.

- Warren
 
Greetings !
Originally posted by Hydr0matic
What do you think, is science in denial ?
Denial of what ?
Science is the (or at least it aspires to be) the
perfect objective recording and translation of the
observed reality. It has (or at least shouldn't
have if it's REAL science) no prior assumptions
(except existence itself maybe).
Originally posted by Hydr0matic
There are no ways to build a deterministic model
of small-scale behavior in this universe. Period.
Now THAT is denial.

Live long and prosper.
 
There are no ways to build a deterministic model of small-scale behavior in this universe. Period.
I agree.

That a variable is 'statistically predictable' does not imply it has some deterministic cause at all.
No, but that and the fact that it varies with atomic structure are strong indicators that it isn't governed by chance. Not knowing the cause of an effect does not imply there's no cause at all.

Also, believing everything happens for a reason does not necessarily mean believing all is predictable. I recognize uncertainty, but not the copenhagen interpretation. I don't know if that qualifies as deterministic ? [?]

Denial of what ?
.. of the fact that there probably is a very reasonable cause for radioactivity, which science has been unable to find.

... perhaps
 
There is a cause of radioactivity. Uranium atoms are, for example, in a low state of entropy, unstable, far from the ground state. So it's only a matter of time before a neutron pops out and generates radiation.
 
Uranium atoms are, for example, in a low state of entropy, unstable, far from the ground state
That's circular reasoning. The definition of an unstable atom involves it being radioactive. But even so, that still doesn't explain how and why the neutron pops out at that specific moment.
 
Originally posted by Hydr0matic
That's circular reasoning. The definition of an unstable atom involves it being radioactive. But even so, that still doesn't explain how and why the neutron pops out at that specific moment.
The neutron has a non-zero quantum amplitude to exist outside the nucleus. It will appear outside the nucleus with calculable probability during any given time frame.

Such probabilities are the very firmament of quantum mechanics -- everything is ultimately based upon such amplitudes.

In our physical knowledge, there is no deeper answer that what I gave in my first sentence of this post. There is, however, rigorous proof that no deterministic model is able to converge to appear probabilistic in the appropriate physical limits. The Aspect experiments and Bell inequalities forbid it. If these proofs to out to be wrong, nearly every bit of our understanding of the world will be shown to be incorrect.

- Warren
 
There is Bohm's "Implicate Order" and the concept of "Wholeness in Time". This could provide order over an interval, but it presently yields no predictive ability.
 
Originally posted by chroot
There are no ways to build a deterministic model of small-scale behavior in this universe. Period.
Bold claim. Think we'll see it happen in our lifetime.

In our physical knowledge, there is no deeper answer that what I gave in my first sentence of this post. There is, however, rigorous proof that no deterministic model is able to converge to appear probabilistic in the appropriate physical limits. The Aspect experiments and Bell inequalities forbid it. If these proofs to out to be wrong, nearly every bit of our understanding of the world will be shown to be incorrect.
Yes, when you postulate miracles, its expected that you can proove impossibility of determinism. Aspect, Bell, still arguable. QM has fever. Do you have any pointer handy regarding that rigorous proof? Maybe I'm full of crap, but I can't imagine how sufficiently complex quantum system creating even single equilibrium of forces implying irrational values of ratios can stay deterministic. Besides, there is no closed system in this universe. period.

Also, "appears" is the keyword. Take a look at simple deterministic system, that's extremely unstable in terms of appearance.
http://www.isp.nwu.edu/~rocky/Pendulum/QuadruplePendulum.html
Imo, this is a good example to visualise that even slightest infinitesimal disturbance from outside would develop into apparently random behaviour. Its not possible to determine state of such system without disturbing it, so for observer, by any means, this system behaves randomly. Yet its completely deterministic.
 
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  • #10
Originally posted by wimms
Bold claim. Think we'll see it happen in our lifetime.
That would require tossing quantum mechanics and everything based on it into the dumpster. I don't see that happening.
Besides, there is no closed system in this universe. period.
The universe itself is a closed system.

Its not possible to determine state of such system [pendulum] without disturbing it, so for observer, by any means, this system behaves randomly. Yet its completely deterministic.
It is deterministic only up to a specific number of decimal places. Quantum mechanics deals with things that are very small.
 
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  • #11
Greetings !

Regarding radioactivity, perhaps one
possibility is some rear combination
of Zero-Point energy fluctuations that
triggers the nuclear decay.

This could explain the predictable
uncertainty of the phenomenon in terms
of the HUP instead of going into "trouble"
with each individual radioactive atom.

Live long and prosper.
 
  • #12
Originally posted by russ_watters
That would require tossing quantum mechanics and everything based on it into the dumpster. I don't see that happening.
It wasn't cute anyway. But yeah, maybe we should die out first.

-- The universe itself is a closed system.
Is that proved already??

It is deterministic only up to a specific number of decimal places. Quantum mechanics deals with things that are very small.
What was that supposed to mean? How about Planck scale pendulum, with say 10E200 links, and say 10E55 fps instead of 24?
 
  • #13
My understanding is that a system can not spontaneousely decay (transit from one state to another). But it can interact with something which makes this system to decay. Now, what if this "something" is a virtual particle of a kind which strongly interacts with such system, and of energy which matches system's energy? Then interaction is very possible and the system will transit from one state to another.

That is how I consider "spontaneous" decays of all kinds happen.

What makes particle(s) - photons, electrons, neutrons, etc to appear out of vacuum is the fact that they all are waves, and waves have pairs of mathematically entangled properties (spread of wave number(momentum) and spread in space,or spread of energy and spread in time, etc). Thus the Hezenberg uncertainty and all quantum mechanics with it.

But what makes certain wave to appear at some particular space-time location, I don't know. May be, particles are bits of space-time itself? Or space-time have wave structure too? Or both are just two sides of same object? Dunno for sure.
 
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  • #14
Originally posted by wimms
Bold claim. Think we'll see it happen in our lifetime.
I'm really not in the mood to argue with crackpots today. Scientists don't go about believing in something because it's cute, or not cute. Scientists believe in things because they are willed into believing them by experiment.

Bell showed conclusively that there are no deterministic models (the so-called "hidden variable" theories) that can explain observed quantum behavior. It's a mathematical, i.e. fully rigorous, proof. Just because you don't like it doesn't mean it's false.

- Warren
 
  • #15
Greetings !
Originally posted by chroot
I'm really not in the mood to argue with
crackpots today. Scientists don't go about
believing in something because it's cute,
or not cute. Scientists believe in things
because they are willed into believing them
by experiment.

Bell showed conclusively that there are no
deterministic models (the so-called "hidden
variable" theories) that can explain observed
quantum behavior. It's a mathematical, i.e.
fully rigorous, proof. Just because you don't
like it doesn't mean it's false.
Did Bell's Theorem also prove there're no
solutions using additional dimensions
of time/space ? Did it prove there're no
solutions using other stuff we've yet never
considered ? A proof is good for a whole
complete abstract theory that has all the
data, we do not have all the data - because
this abstract theory is about reality.

Live long and prosper.
 
  • #16
I think all physics is determined by the smallest possible thing (i.e. superstring are thought to be it, at the moment). There limitations determine the way our universe works, thus if we change a superstring of sorts, it could be that we can change physics to allow for what we want to do, then we become gods :)

if you think about that for a minute it makes ense :) something has to determine everything, so what else than the thing everything is made out of... however, you could say its the components of the superstring (i.e. the things holding them together and the string things) that individually determine physics.

I don't believe its chance in the least, where the universe is concerned everything is very well defined :)
 
  • #17
Originally posted by Bunting
I don't believe its chance in the least, where
the universe is concerned everything is very
well defined :)
Which means that you're the "old" type of
materialist and you either do not see
or ignore the apparent inability of all that's
"well defined" to explain its own existence.

Peace and long life.
 
  • #18
Originally posted by chroot
Bell showed conclusively that there are no deterministic models (the so-called "hidden variable" theories) that can explain observed quantum behavior. It's a mathematical, i.e. fully rigorous, proof. Just because you don't like it doesn't mean it's false.
Not up to date are we ?

"They show that despite the supposedly definitive Aspect experiments, in the literature local hidden variable (LHV) theories are definitely not dead both experimentally and theoretically. Its a very impressive collection and lively debate. Thompson in particular has worked hard to uncover pitfalls and show the Aspect data may actually support a LHV theory"

>>> http://www8.pair.com/mnajtiv/qm/bell.htm

I'm really not in the mood to argue with crackpots today.
[zz)] If you weren't, you wouldn't. And if you had anything interesting to say you would say it, instead of coughing up a pathetic line like this. Don't insult your intelligence.

I thought crackpots were the ones that believe in magic ? [?]
 
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  • #19
Originally posted by chroot
I'm really not in the mood to argue with crackpots today. Scientists don't go about believing in something because it's cute, or not cute. Scientists believe in things because they are willed into believing them by experiment.

Bell showed conclusively that there are no deterministic models (the so-called "hidden variable" theories) that can explain observed quantum behavior. It's a mathematical, i.e. fully rigorous, proof. Just because you don't like it doesn't mean it's false.
Must have hit a soft-spot. You know that when scientists appeal to authority - you're stupid, we're smart.
Yeah, Bell's theorem is serious stuff. But, its implications are evaluated in frame of current theories, that are incomplete. a lot of assumptions. That no deterministic models can explain observation is just one of possible conclusions. If science was so chilled about state of things, there wouldn't be tens of alternate theories in works by serious scientists.
 
  • #20
If science was so chilled about state of things, there wouldn't be tens of alternate theories in works by serious scientists.

Serious != knowledgeable.


Must have hit a soft-spot. You know that when scientists appeal to authority - you're stupid, we're smart.

A lot of times, the part I marked in boldface is true. (do not interpret this as an assertion it is true now)



Anyways, if what I understand about quantum measurement theory is correct, then QM has no problem admitting a completely deterministic underlying theory; the catch is that deterministic theory cannot a theory of simultaneous exact position & momentum.

The classical presumption is that position and momentum are non-probabilistic ideas; that they are a fundamental, so classicist is forced to interpret quantum states as probability amplitudes.

However, it is just as valid to take quantum states as the fundamental well-defined object and declare position and momentum as probablistic measurements of a quantum state.

From the latter point of view, a deterministic universe is consistent with the theory; it is acceptable that detectors are really deterministic, merely shaping the typical statistical distribution of our incomplete knowledge into things that look like the concepts we wish to call position and momentum. If we had perfect knowledge of the underlying universe, the output of these detectors would no longer look like position & momentum.
 
  • #21
Originally posted by Hurkyl
Serious {scientists} != knowledgeable.
I didn't mean laymen like me :smile: by that, but people like you.. Are you admitting that large portion of scientific world are no better crackpots than what we can find on forums?

A lot of times, the part I marked in boldface is true. (do not interpret this as an assertion it is true now)
I have no problem with either assertion. I know my limits. Catch is that in majority of cases intelligent people do no resort to pointing out those limits as argument. Only when they get seriously disturbed.

Anyways, if what I understand about quantum measurement theory is correct, then QM has no problem admitting a completely deterministic underlying theory; the catch is that deterministic theory cannot a theory of simultaneous exact position & momentum.

The classical presumption is that position and momentum are non-probabilistic ideas; that they are a fundamental, so classicist is forced to interpret quantum states as probability amplitudes.

However, it is just as valid to take quantum states as the fundamental well-defined object and declare position and momentum as probablistic measurements of a quantum state.

From the latter point of view, a deterministic universe is consistent with the theory; it is acceptable that detectors are really deterministic, merely shaping the typical statistical distribution of our incomplete knowledge into things that look like the concepts we wish to call position and momentum. If we had perfect knowledge of the underlying universe, the output of these detectors would no longer look like position & momentum.
Exactly. Form and interaction are inseparable. Thing IS what it appears to other thing to be. As long as you look at things as you perceive them, there is not way to describe them deterministically, and you resort to probablistic ideas.
 
  • #22
There is no point to assume unneeded.
 
  • #23
Originally posted by Hydr0matic
I have to ask, is there any sensible reason to believe that physical processes, let's say radioactivity, is governed by chance ? Isn't that conclusion unwarranted ?

What do you think, is science in denial ?

You are answering your own question. You freely admit that experimental evidence is in favor of the laws of chance (the statistical laws we all know and love). And then you ask if that same conclusion is unwarranted.

The answer is that all available evidence, without exception, points to the existence of purely random effects at the subatomic level. There are no known exceptions. Your example, nuclear decay, is as pure a proof as anything. If there were such a cause - for the decay of a radioactive isotope - you have only to present it to be assured of your Nobel.

It is unreasonable to assume that which you seek to prove - i.e. that the appearance of randomness is actually explained by something which has yet to be discovered. Bell/Aspect successfully fielded the challenge by providing a coupe d'etat to the hidden variable theories. Now HV theories must additionally explain the experimental results predicted by the original quantum mechanical theory of the 1920's, and that is no easy task.

Because... even if you deny that Bell/Aspect is the nail in the coffin, you are left with the fact that the HV theories must replicate the all of the predictions of QM. So tell me again who is in denial?
 
  • #24


Originally posted by DrChinese
Because... even if you deny that Bell/Aspect is the nail in the coffin, you are left with the fact that the HV theories must replicate the all of the predictions of QM.
Sure, no question about that. Problem raised is how can science founded on strict cause-effect correlation assumptions continue to explain reality that is allowed to be based on principally acausal effects.

If fundamental reality is completely purely random, at which point and with what HV does observable causal reality appear? Isn't there paradox in it - it can't be deterministic, and it can't be random either?

Its like saying that universe is completely random, but if you look long enough, you notice patterns, that happen to be our fundamental forces, that by pure chance happen to be exactly the same everywhere.
 
  • #25


Originally posted by wimms
Sure, no question about that. Problem raised is how can science founded on strict cause-effect correlation assumptions continue to explain reality that is allowed to be based on principally acausal effects.

Good point. Does the scientific method presuppose determinism? This would be worthy of further discussion...
 
  • #26


Originally posted by DrChinese
Does the scientific method presuppose determinism?
What else logical reasoning and proof is?

Bell's proof is time invariant. So are most theories. Computer age has given us a lot of iterated nonlinear functions that have no reversibility, ie you can't reverse-engineer them. Their output appears random by all means. Yet it isn't random.
I wonder, if something irreversible happens at particle level, is there even any remote chance to find cause-effect pattern without trying real hard to crack the crypto first, using heavily indirect hints?

How many theories have looked into iterative closest range particle behaviour where timeflow of particles themselves is heavily variable, being for eg. function of energy, ie is both cause and effect? Linear equations are useless there.
 
  • #27


Greetings !
Originally posted by DrChinese
Does the scientific method presuppose determinism?
The scientific method is (or at least should be)
observation. We observe and then we discribe.
The HUP, for example, made no deterministic (as
determinism was viewed before QM) sense and yet
we managed to observe and discribe it mathematicly.
I think that if you view science as a presupposition
of anything then you're creating a belief.
I do, however, think that the scientific method
should include certain "preferences". The reasons
fot that are :
1. If we observed patterns in the past with certain
general qualities that are the same, it makes
sense to try these qualities first when verifying
or considering a theory.
2. A "deeper" reason would not just be the
simple common qualities but the entire theoretical
framework of our thought about reality and even much
of the abstract. That is, the more basic assumptions
that we really do not seem to be able to do without.
It'll be reasonable to prefer this approach first
and change it only if it gets us stuck.
Originally posted by DrChinese
This would be worthy of further discussion...
Phil. forum. :wink:

Live long and prosper.
 

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