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Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

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Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#151

Post by staticassertion »

Nevermark wrote: post #150
staticassertion wrote: post #148

Earlier quoted context omitted.

> My understanding of brute facts, is they are free values in theory, but measured values in practice. And somehow we just accept experimental measurements of some things as the end of explanation. What you accept as a brute fact is conditional on your world view. For most people it's going to be very little, like "the initial state of the universe" or "the constant values of the universe" etc, although the latter is…

> What you accept as a brute fact is conditional on your world view. Thanks again, for your patience on this. Ok, is there is a subjective aspect? Driven by practicality of course? A pragmatic limit to explanation searches would make sense to me. It could even be for objective reasons, such as that our universes laws somehow prevent us from gathering enough information to pin down why something is determined the way…

I think we're running across the varying forms of the Principle of Sufficient Reason, which is, again, a somewhat contentious area of philosophy.

> I think everything is fully determined, even if we may not ever achieve a full explanation of that determination. Is that consistent with brute facts?

That depends. Your statement is effectively the "Strong PSR" - every fact is preceded by another explanatory fact.

There are weaker forms of the PSR or you can reject the PSR. I believe Sean Carrol, for example, completely rejects the PSR. This is not out of laziness, it's because he considers the PSR to be an unnecessary and costly commitment with weak justification, and that our best models of physics don't require or benefit from it (my recollection).

> Yes. The speed of light is a result of conservation constraints and local (i.e. our universe's) structure. The topology of space-time, general relativity, quantum properties of photons must all contribute. And presumably other factors we have yet to understand.

This seems to be framing the speed of light as contingent on other properties of the universe, but that just pushes us back. We could just ask if the gravitational constant is a result of other facts, for example, since you have appealed to that as an explanatory factor for C.

I could ask what explains the structure of the universe. You can then say that it's logically necessary, which is basically just saying that it's brute but with a heavier burden (you'd have to show the logical primitives you use to assert that, but the outcome is the same) or brute or brute contingent, or you'd have to say there's an infinite regress.

You can keep saying "Ah but there's this property of a photon" but now you have to explain that property. Your approach seems to be to try to derive a logical necessitarian view here by appealing to a principle like "Reality exists, reality contains all things necessarily" and then to derive metaphysical constraints from that but I'm not sure that any of the metaphysical claims are well justified here.

> Presumably, anyone who operates with the principle of brute facts, could have named those as brute facts, before they were solved?

Of course. And they would have been wrong. In general, models attempt to minimize brute facts because of their cost, but all models have costs. If you want to express that the universe is unique, or non-contingent, that is a cost of your model. Strong PSR is itself a heavy metaphysical claim that will bring along its own commitments.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#152

Post by superposeur »

prmph wrote: post #117
superposeur wrote: post #40

Earlier quoted context omitted.

Yes, the MWI is falsifiable. It asserts that objective collapse does not occur, therefore any observation of objective collapse (such as predicted by GRW or Penrose-Diosi) would falsify it.

That's not true falsifiability; its asserting a negative. I think people resort to MWI because they think it explains everything neatly; it does not! For example, from my perspective, it does not explain what world I end up in, and if you are saying it's random, you need to come with a fundamental theory of randomness, unless the response is: it just exists, deal with it.

If this experiment: https://ui.adsabs.harvard.edu/abs/2024arXiv240202618T/abstra... or others like it turn up positive results, MWI is falsified.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#153

Post by jadbox »

thyristan wrote: post #4
jadbox wrote: post #2

How does "quantum darwinism" effectively select a state? Like how does that work in principle- what is the selection criteria.

Energy.

Do you mean Energy conservation? That's interesting and would make sense as a successful evolution of pattern replications.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#154

Post by Nevermark »

staticassertion wrote: post #151
Nevermark wrote: post #150

Earlier quoted context omitted.

> What you accept as a brute fact is conditional on your world view. Thanks again, for your patience on this. Ok, is there is a subjective aspect? Driven by practicality of course? A pragmatic limit to explanation searches would make sense to me. It could even be for objective reasons, such as that our universes laws somehow prevent us from gathering enough information to pin down why something is determined the way…

I think we're running across the varying forms of the Principle of Sufficient Reason, which is, again, a somewhat contentious area of philosophy. > I think everything is fully determined, even if we may not ever achieve a full explanation of that determination. Is that consistent with brute facts? That depends. Your statement is effectively the "Strong PSR" - every fact is preceded by another explanatory fact. There…

Brut facts. Principle of Sufficient Reason. I am getting a vocabulary bump here. I spent some time further expanding my vocabulary on related concepts on Wikipedia.

> Your statement is effectively the "Strong PSR"

I would agree with that.

But coming across the Münchhausen trilemma, the idea that all proofs need prior assumptions, or must be one of: (1) a circular argument, (2) an infinite regression, or (3) dogma, I disagree with that.

Some truths are the result of co-constraint. This is where each component of the solution is both an implication of all other components, and an antecedent for all other components. This avoids the trap of being a circular argument, when it can show that any alteration of choices leads to contradiction. Strong proofs of contradiction can be made without infinite regression.

If N co-constrained features can be shown to be consistent, and for N-1 features at least, alternatives to each can be shown to lead to contradiction, then we have a unique solution - it must be the solution. (N-1 comes from the fact, that given co-constraints that lead to one solution, any single feature can be determined by the other N-1.)

That demonstrates that constraint/determination can avoid infinite regression, with recurrent loops of implication, which don't just prove consistency (sufficient), but failure of alternatives (necessity).

Reality must have this form of being. (1) It cannot be determined by any priors or assumptions, because there are no priors. (2) It cannot be determined by infinite regress, because there is no where beyond reality to regress. And obviously, (3) dogma isn't an explanation.

Specific structure must be due to internal consistency (sufficiency), without external or unexplained facts (self-sufficiency), the demonstrated insufficiency or contradiction of any variation or alternative (necessity), and compatibility with our physics (experimental testing that can be made ever more stringent).

> This seems to be framing the speed of light as contingent on other properties of the universe, but that just pushes us back.

I agree. In terms of explaining local physics.

Local properties are most likely to be explainable with the typical regression of explanation, backed up by experimentally verified "axioms", which will then lead to deeper explanations. For local physics, we cannot just prove mathematically that a relationship can work, or even must work, but that the local conditions also require it.

Even a perfect Platonic tautological necessity for a sub-structure of reality, must be experimentally demonstrated to apply locally. We have to establish that we are "there", experimentally.

Even then, in a less pure sense, we may still beneficially use co-constraints, while also regressive knowledge. I.e. explanation = (regressive knowledge) + (co-constraint = circular consistency + inconsistency of alternatives), in order to validate both sufficiency and necessity.

Many proofs of inconsistency can rule out local solutions, without regression. Contradictions are contradictions regardless of priors.

> I could ask what explains the structure of the universe. You can then say that it's logically necessary, which is basically just saying that it's brute but with a heavier burden.

My view is, an explanation of reality will need to demonstrate sufficiency, in terms of being (1) self-consistent, (2) consistent with hosting a region with what we know of our local physics, and (3) to avoid simply being a circular argument, demonstrate that alternatives to the explanation necessarily are contradictory.

Those are three kinds of knowledge to triangulate from.

That would be an approach compatible with strong PSR.

And starting with that, I work from self-containment, self-consistency, and self-determination, as tautological constraints, leveraged as working tautological axioms.

I think it is fair to say, while some may believe a theory of everything with unexplained brut facts can be valid (some things being just what they are), few or none would be unsatisfied with a theory that demonstrated all facts were well determined, was consistent, could be shown to be compatible with our region of reality, and could not be altered without creating a contradiction.

So that is my target.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#156

Post by anon291 »

Veedrac wrote: post #149
anon291 wrote: post #103

Earlier quoted context omitted.

I think the claim is this: the wave function never collapses. However, the effect of the wave function on the environment quickly converges to only one of the two states. We could not know the difference because we cannot directly observe the wave function. We only can see the result as it is magnified onto a macro scale by our observation equipment (or, lacking that, our eyes, which themselves turn a tiny microscopi…

My confusion is that this is just Many Worlds / the Schrödinger equation, and Quantum Darwinism doesn't seem to add anything that wasn't already obvious by inspection. But after reading more, I think that's kind of the point? It's ultimately just an argument for why the Schrödinger equation produces these locally classical regions, plus a bunch of overly flowery prose and dressing up in invented jargon that can mostl…

Many worlds is not the Schrodinger equation. No I don't think this is many worlds. The decision is made uniquely and then is amplified.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#157

Post by Veedrac »

anon291 wrote: post #156
Veedrac wrote: post #149

Earlier quoted context omitted.

My confusion is that this is just Many Worlds / the Schrödinger equation, and Quantum Darwinism doesn't seem to add anything that wasn't already obvious by inspection. But after reading more, I think that's kind of the point? It's ultimately just an argument for why the Schrödinger equation produces these locally classical regions, plus a bunch of overly flowery prose and dressing up in invented jargon that can mostl…

Many worlds is not the Schrodinger equation. No I don't think this is many worlds. The decision is made uniquely and then is amplified.

Many worlds is just the claim that the Schrödinger equation holds in actuality.

I don't think QD makes decisions 'uniquely'. Take this quote,

> The step from the epistemic (“I have evidence of |π17〉”.) to ontic (“The system is in the state |π17〉”.) is then an extrapolation justified by the nature of ρS⁢ℰ: Observers who detected evidence consistent with |π17〉 will continue to detect data consistent with |π17〉 when they intercept additional fragments of ℰ. So, while the other branches may be in principle present, observers will perceive only data consistent with the branch to which they got attached by the very first measurement. Other observers that have independently “looked at” S will agree.

https://pmc.ncbi.nlm.nih.gov/articles/PMC9689795/

Emphasis on "the other branches may be in principle present" — the claim at least in this paper can't be that all branches agree, just that they agree locally.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#158

Post by anon291 »

Veedrac wrote: post #157
anon291 wrote: post #156

Earlier quoted context omitted.

Many worlds is not the Schrodinger equation. No I don't think this is many worlds. The decision is made uniquely and then is amplified.

Many worlds is just the claim that the Schrödinger equation holds in actuality. I don't think QD makes decisions 'uniquely'. Take this quote, > The step from the epistemic (“I have evidence of |π17〉”.) to ontic (“The system is in the state |π17〉”.) is then an extrapolation justified by the nature of ρS⁢ℰ: Observers who detected evidence consistent with |π17〉 will continue to detect data consistent with |π17〉 when the…

Without defining what 'actuality' is, then there's no meaning to 'the Schrodinger equation holds in actuality'. In their own way, all interpretations of quantum mechanics claim the Schrodinger equation holds in 'actuality'. Some view probability and potential as a claim on 'actuality'. Others dismiss this and instead view probability skeptically and claim it must thus be true. This is an ontological argument, not a scientific one.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#159

Post by srean »

qsera wrote: post #123
srean wrote: post #80

Earlier quoted context omitted.

What is mysterious to me is why and how chemical reactions in a certain part of my brain create an experience of blue. Yes some chemical change happened there, but so what. These are not very unusual chemical reactions. They happen and are happening everywhere. Does all the chemical reactions going on generate an experience to some experiencer?

I think the flaw in your reasoning is the assumption that chemical reaction is causing the sensation of blue. But imagine if the consciousness and what it senses cannot be separated. So the consciousness sensing blue and the chemical reaction happening in the brain, are just correlated. One did not cause the other. One can ask where that correlation came from. I think that the such correlations are inherent in such w…

That is an interesting thought.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#160

Post by Veedrac »

anon291 wrote: post #158
Veedrac wrote: post #157

Earlier quoted context omitted.

Many worlds is just the claim that the Schrödinger equation holds in actuality. I don't think QD makes decisions 'uniquely'. Take this quote, > The step from the epistemic (“I have evidence of |π17〉”.) to ontic (“The system is in the state |π17〉”.) is then an extrapolation justified by the nature of ρS⁢ℰ: Observers who detected evidence consistent with |π17〉 will continue to detect data consistent with |π17〉 when the…

Without defining what 'actuality' is, then there's no meaning to 'the Schrodinger equation holds in actuality'. In their own way, all interpretations of quantum mechanics claim the Schrodinger equation holds in 'actuality'. Some view probability and potential as a claim on 'actuality'. Others dismiss this and instead view probability skeptically and claim it must thus be true. This is an ontological argument, not a s…

If you don't like the word 'actuality', I can rephrase. Many worlds is just the claim that physical reality materially evolves in correspondence with the Schrödinger equation.

If you want to quibble over what it means for something to be material, go ahead, but unless you can tie it to some specific claim being made about QD I don't really know what the exercise gets you.

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