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Why have so many physicists shrugged off the paradoxes of quantum mechanics?

thenewatlantis.com

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Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#41

Earlier quoted context omitted.

And that is exactly why it isn't a paradox in quantum mechanics. Quantum mechanics is consistent for the domain of questions it was designed to ask: particle scattering experiments. It's when people push it into philosophy or other unintended domains that they run into problems.

QM and GR are inconsistent. If you don't see that as a fundamental research problem you're not doing science, you're just treading water.

A paradox is an internal inconsistency. Noone claims that quantum mechanics is the fundamental theory of everything. Like the convergence of a taylor series, there is a range of energies within which it produces correct calculations, and if you go outside that the result is undefined.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#42
post #25

Earlier quoted context omitted.

Philosophical issues mean that the theory is wrong and new physics will come from their resolution, and thus philosophical issues can be decided experimentally.

We may be using different definitions of the word philosophical. I'm classifying anything that can be decided experimentally as scientific. These interpretations are identical from an experimental standpoint.

That's a circular argument. It doesn't prove that experimental differences between interpretations are impossible.

The existence of such a proof would provide a genuine scientific basis for not continuing to address the problem.

Without that proof, the problem remains open.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#43
post #36
post #26

Earlier quoted context omitted.

You've just replaced the problem of collapse with the problem of which universe we transition to. We are only in one.

To be more precise, we are in all of them, but our consciousness only perceives one of them. So the real problem isn't in quantum mechanics, it's in what the hell consciousness is and why it works the way it does. However, note that you can have observations performed by a computer which e.g. counts events, and the counter will exist in all "worlds" (branches of the universal wave function, really), while each incarn…

Why is it necessary for consiousness to be any different from that computer counter? It seems to me that the paradoxical idea is not quantum mechanics, but rather conciousness.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#44

Earlier quoted context omitted.

QM and GR are inconsistent. If you don't see that as a fundamental research problem you're not doing science, you're just treading water.

A paradox is an internal inconsistency. Noone claims that quantum mechanics is the fundamental theory of everything. Like the convergence of a taylor series, there is a range of energies within which it produces correct calculations, and if you go outside that the result is undefined.

Strictly speaking that is a QFT problem, or really a standard model problem, moreso than a quantum mechanics problem. In order for it to be a quantum mechanics problem it would have to happen everywhere in quantum mechanics, and the single electron Schrodinger equation hydrogen atom definitely has no (theoretical) problem.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#45

Earlier quoted context omitted.

QM and GR are inconsistent. If you don't see that as a fundamental research problem you're not doing science, you're just treading water.

A paradox is an internal inconsistency. Noone claims that quantum mechanics is the fundamental theory of everything. Like the convergence of a taylor series, there is a range of energies within which it produces correct calculations, and if you go outside that the result is undefined.

Here's a nice paradox:

https://arxiv.org/pdf/1902.05080.pdf

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#46
quantum mechanics has two different laws that describe how a system changes in time.

Rule 1 says that except during a measurement, the wave evolves smoothly and deterministically, exploring every possibility.

Rule 2 says that during a measurement of position, the wave collapses around the position where it's seen, with a probability proportional to the square of the height of the wave, before the collapse.

It is only Rule 2 that mentions probabilities at all.

And, Rule 1 and Rule 2 are in catastrophic tension with each other.

Rule 1 says that there are always all possible outcomes. Rule 2 says there is only 1 outcome and it's picked out with some probability rule.

It's pretty contradictory - is there one outcome or all outcomes?

> youtube.com/watch?v=Zri9gS1w5ok Perimeter’s Lee Smolin will argue that the problems that have bedeviled quantum physics since its inception are unsolved and unsolvable for the simple reason that the theory is incomplete.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#47
These idea is interesting, but, I had a different idea, is constraint interpretation. Mathematics is the real reality. For example, some equations can have multiple solutions, such as x^2+2x-3=0 can be 1 or -3. If you make the experiment that you have a entangled photons and you are on a different planet, you can measure it and if the people on other planet measure it in the same way they will get the same answer; it doesn't go "instantly" or at any other speed; the constraint is they are same, and this entanglement propagates backward in time from the point of view from both experimenters; it doesn't say if one is "before" or "after" another one. You can trace it backward in time to the source and forward in time to the other experimenter, and that is the line of the constraint.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#48
post #18

Earlier quoted context omitted.

A paradox is essentially a logical contradiction. As far as we know such contradictions don't occur in nature. Paradoxes indicate that there is a flaw in either our theory or our understanding of our theory.

right. but saying there aren't paradoxes in quantum mechanics isn't helpful and is probably just wrong. quantum mechanics isn't a physical thing and isn't reality. it is a model. of course it can have paradoxes, and does.

A model with a paradox is usually considered a flawed model, as it a logical contradiction, and from a logical contradiction anything can be proven.

"Proof by contradiction" is a proof that the opposite is true, and is constructed so that if the thing you try to disprove would be true, you could create a paradox/contradiction.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#49

> Bohr postulated a distinction between the quantum world and the world of everyday objects. A “classical” object is an object of everyday experience. It has, for example, a definite position and momentum, whether observed or not. A “quantum” object, such as an electron, has a different status; it’s an abstraction. Some properties, such as electrical charge, belong to the electron abstraction intrinsically, but other…

I skimmed a paper about twenty years ago that pretty much explains the deference to me.

Macroscopic objects are subject to quantum mechanical cascades. The end result is the probability constraints for an object composed of an enormous number of interacting particles rapidly goes to zero.

The example was a playing card stood on a knife edge. The probability cascade causes it to fall one direction or the other. We can't predict which side it will fall over on. But it will fall.

Re: Why have so many physicists shrugged off the paradoxes of quantum mechanics?

#50

> Bohr postulated a distinction between the quantum world and the world of everyday objects. A “classical” object is an object of everyday experience. It has, for example, a definite position and momentum, whether observed or not. A “quantum” object, such as an electron, has a different status; it’s an abstraction. Some properties, such as electrical charge, belong to the electron abstraction intrinsically, but other…

> with an error that is so small that you can just ignore the uncertainty and approximate them as classical objects.

I’d say that’s the gist of it, that we cannot “just ignore” the uncertainty because it’s too small, because if you do that then your model and the real world are indeed different. Also, at the end of it all what does “too small” mean? “Too small” compared to what? To a galaxy? To a super-nova? To a planet? To a cat? To the things we try to “discover” at CERN? To things smaller than them? To say nothing of the fact that comparing a number to physical stuff will eventually bring you head on against Zeno’s paradox, one way or the other.

I agree though that using the “too small” trick does generally allow us to do great things, like send stuff to the confines of the solar system or to build nuclear bombs, i.e. it allows us to be efficient, but that does not mean that by being efficient our models are also identical representations of what reality really is, so to speak.

What I’m saying is that maybe the “mathematization” of the physical world is a leaking abstraction, and that maybe we’d be better off by saying “we’ll never really know what the world is made up of”. But the problem is that they haven’t awarded science Nobel prizes to people saying “there’s really no way for us to learn how the Universe really works”, at least not that I know of, at best you’re seen as a mysticist when saying that, at worst as a know-nothing or a cynic.

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