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Superdeterminism: The path we didn’t take

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Re: Superdeterminism: The path we didn’t take

#41

Post by knzhou »

millstone wrote: post #39
knzhou wrote: post #7

I've always been mystified at why people take superdeterminism as a good explanation for anything, when it actually acts as a stopsign for thought. For example, suppose I am betting with you on the outcomes of a coin toss. You call heads, the coin comes up tails, you give me some money. You call tails, the coin comes up heads, you give me some more money. This repeats a number of times. The common sense response is t…

The linked paper addresses this objection in a fun way: perhaps the tobacco company lawyers argue in court that "smoking doesn't cause cancer; every experiment was super-determined to assign those pre-disposed to cancer into the smoking group!" The paper replies with the following argument: in super-determinism, statistical independence is an emergent property which holds at macro scales, so classical experiments do…

> The paper replies with the following argument: in super-determinism, statistical independence is an emergent property which holds at macro scales, so classical experiments do enjoy statistical independence. In your hypothesis - yeah, the game is rigged!

> But superdeterminism comes into play at the quantum scale where we know things are already kind of fucked, which is why we're talking about this at all.

But experiments already do use classical (i.e. macroscopic) sources of randomness. For example, to oversimplify a little, you might literally flip a coin to decide the specific measurements done in a run of a Bell test experiment. Such experiments still give puzzling results, so if superdeterminism is to work as an explanation of anything at all, it must hold all the way up. Superdeterministic explanations have to apply even to things like coin flips, which, again, leads to the end of science, wailing and gnashing of teeth, etc.

Re: Superdeterminism: The path we didn’t take

#42

Post by gliese1337 »

repsilat wrote: post #34
gliese1337 wrote: post #12

I find it strange that they claim that QM lacks any explanation for measurement. There are explanations for measurement. Not everyone agrees with any single one of them, but they definitely exist. Superdeterminism is one, but it's not the only one. It is really only the Copenhagen Interpretation of QM that has a measurement problem. Personally, I am on board with the "measurement is just entanglement" solution (it se…

I'm also a Many-Worldser, but I don't quite know how to answer the question "How does the Born Rule work?" That is, if "worlds" branch off with some amplitudes, and there's a "me" on this branch and another on that branch, how does it make sense to talk about the probability of "me me" being this one or that one? Empirically we know how to calculate it from the amplitude, but why is that more reasonable than any othe…

Well, yeah, there is that... I suppose one could argue that lacking an a-priori explanation for the way probability is allocated over state-space is equivalent to lacking an explanation for measurement, but that seems to me like claiming that we have no answer to how thermal emission of light works because we can't explain the measurement rule in QM, which I expect most physicists would balk at.

Yea, there is still work to be done at a lower level, and there are other competing explanations at this level, but that doesn't mean that we don't have an explanation at this level. "How does the Born Rule work?" is a lower-level question than "how does measurement work?"

Re: Superdeterminism: The path we didn’t take

#43

Post by knzhou »

npo9 wrote: post #37
knzhou wrote: post #26

Earlier quoted context omitted.

While I can think of exciting questions sparked by many different interpretations of quantum mechanics, I can't think of any for superdeterminism, for exactly the reasons I said -- it's scientifically dead from the start. Other ideas have limits, superdeterminism doesn't. Do you have a good example?

In Superdeterminism the obvious line of research is to look for hidden variables when we find things that are seemingly probabilistic or random. If we found hidden variables to control when a radioactive isotope will decay we could possibly have much safer handling of fission materials, depending on what these hypothetical hidden variables are. * I don’t have an opinion on Superdeterminism, I’m just thinking about hy…

Hidden variables would be cool. But there are plenty of hidden variable theories that aren't superdeterministic. My point is that if we all genuinely adopted the superdeterministic way of thinking and explaining, we wouldn't even do experiments in the first place.

Re: Superdeterminism: The path we didn’t take

#44

Post by AgentME »

selestify wrote: post #23
Simon_says wrote: post #18

Earlier quoted context omitted.

Realism is the axiom to give up, not locality. Just accept MWI as the current best guess and get on with your life.

There’s no evidence MWI is the best guess compared to other interpretations

It's simpler (as in fewer rules; not that it results in a "simpler" smaller world) than a lot of other interpretations: it doesn't need to specify an explicit concept of wave collapse.

Re: Superdeterminism: The path we didn’t take

#45

Post by username90 »

knzhou wrote: post #38
perl4ever wrote: post #35

Earlier quoted context omitted.

I'm definitely not distinguishing between determinism and superdeterminism. The wikipedia page on superdeterminism starts out: "In quantum mechanics, superdeterminism is a hypothetical class of theories that evade Bell's theorem by virtue of being completely deterministic" Logically, something that is "completely deterministic" would have to be...deterministic, no? Does superdeterminism go to 11?

Superdeterminism is determinism, plus a radically different way of thinking about experimental results. To continue with the coin flip analogy, consider a classical world where a coin flip is perfectly deterministic, given the initial conditions. In the usual way we think about determinism, it's still possible to test whether a coin is fair. Just flip it a bunch of times, a little differently each time, and see if yo…

> It's on the level of answering "God did it" to every question.

And saying that it is random with "God rolled a dice" isn't? The entire universe could have used a fixed random seed and our experiments and thoughts would have been exactly the same for all we know, determinism doesn't have the effects you talk about. We perform trials and do statistics when we don't know the exact workings of things, not because we believe that the thing is inherently random.

Re: Superdeterminism: The path we didn’t take

#46

Post by millstone »

themgt wrote: post #8

I find this Quora answer convincingly reflects my thinking as to why Superdeterminism can't possibly be correct given Bell’s theorem[1] Skimming the actual paper[2] I'm not really seeing a convincing explanation, this in particular just strikes me as hard to believe / failing Occam's razor: The belief that such tests tell us something about (the implausibility of) Superdeterminism goes back, once again, to the idea t…

I would say it like so: pi has many transcendental neighbors, which are in no way related to pi. But e and pi, despite being numerically distant, are in one sense "close" - related - via Euler's formula. So there's a "local closeness" - the arithmetic difference of pi and its neighbor - but also a "relationship closeness" where pi and e are intimately linked.

Perhaps quantum states obey the relationship closeness, not the arithmetical one. Classical physics obeys "arithmetical closeness" meaning that small differences in dynamical properties are close in state-space. But actually this is an emergent property: highly sensitive quantum experiments reveal that small differences in dynamical properties can be highly separated in state-space.

Rationals are all pretty easily related, but pi has nothing in common with a random close transcendental neighbor.

More: https://en.wikipedia.org/wiki/Implicate_and_explicate_order

Re: Superdeterminism: The path we didn’t take

#47

Post by knzhou »

username90 wrote: post #45
knzhou wrote: post #38

Earlier quoted context omitted.

Superdeterminism is determinism, plus a radically different way of thinking about experimental results. To continue with the coin flip analogy, consider a classical world where a coin flip is perfectly deterministic, given the initial conditions. In the usual way we think about determinism, it's still possible to test whether a coin is fair. Just flip it a bunch of times, a little differently each time, and see if yo…

> It's on the level of answering "God did it" to every question. And saying that it is random with "God rolled a dice" isn't? The entire universe could have used a fixed random seed and our experiments and thoughts would have been exactly the same for all we know, determinism doesn't have the effects you talk about. We perform trials and do statistics when we don't know the exact workings of things, not because we be…

Again, it's not about randomness vs. determinism. Both are perfectly compatible with science, just as you said, and no scientist bats an eye at using either type of model. Superdeterminism is a big step beyond determinism that explicitly is like saying "because God did it".

Re: Superdeterminism: The path we didn’t take

#48

Post by mycall »

knzhou wrote: post #7

I've always been mystified at why people take superdeterminism as a good explanation for anything, when it actually acts as a stopsign for thought. For example, suppose I am betting with you on the outcomes of a coin toss. You call heads, the coin comes up tails, you give me some money. You call tails, the coin comes up heads, you give me some more money. This repeats a number of times. The common sense response is t…

A coin can have 51%/49% probabilities based on weight of one side.

Re: Superdeterminism: The path we didn’t take

#49

Post by npo9 »

knzhou wrote: post #43
npo9 wrote: post #37

Earlier quoted context omitted.

In Superdeterminism the obvious line of research is to look for hidden variables when we find things that are seemingly probabilistic or random. If we found hidden variables to control when a radioactive isotope will decay we could possibly have much safer handling of fission materials, depending on what these hypothetical hidden variables are. * I don’t have an opinion on Superdeterminism, I’m just thinking about hy…

Hidden variables would be cool. But there are plenty of hidden variable theories that aren't superdeterministic. My point is that if we all genuinely adopted the superdeterministic way of thinking and explaining, we wouldn't even do experiments in the first place.

Wouldn’t we?

If Superdeterminism is correct than it wouldn’t be up to us if we continue to experiment. Maybe we are compelled to try to understand the world.

Re: Superdeterminism: The path we didn’t take

#50

Post by perl4ever »

knzhou wrote: post #38
perl4ever wrote: post #35

Earlier quoted context omitted.

I'm definitely not distinguishing between determinism and superdeterminism. The wikipedia page on superdeterminism starts out: "In quantum mechanics, superdeterminism is a hypothetical class of theories that evade Bell's theorem by virtue of being completely deterministic" Logically, something that is "completely deterministic" would have to be...deterministic, no? Does superdeterminism go to 11?

Superdeterminism is determinism, plus a radically different way of thinking about experimental results. To continue with the coin flip analogy, consider a classical world where a coin flip is perfectly deterministic, given the initial conditions. In the usual way we think about determinism, it's still possible to test whether a coin is fair. Just flip it a bunch of times, a little differently each time, and see if yo…

It just seems orthogonal to me. Some people experience superdeterminism viscerally and then they take a pill and the feeling goes away. It's not scientific or unscientific, it's more of an attitude. Also, given the regular appearance of such a feeling in disturbed minds, it seems like a basic feature of human cognition, like say, the capacity to taste salt or something.
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