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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 pap

by themgt 7y ago

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 that a state which is intuitively “close” to the one realized in nature (eg, the wavelength of the light from the distant quasar was a little different, all else equal) is allowed by the laws of nature and likely to happen. However, in a superdeterministic theory what seems intuitively like a small change will generically result in an extremely unlikely state; that’s the whole point. For example, in a superdeterministic theory, a physically possible counterfactual state in which the wave-length of the photon was slightly different may also require changes elsewhere on the past hypersurface, thereby resulting in the experimenter’s decision to not use the quasar’s light to begin with. "Reality is a giant deterministic conspiracy" is more plausible than abandoning local realism? They do (kinda?) propose an experiment at least? [1] https://www.quora.com/Why-do-some-crackpot-scientists-go-after-super-deterministic-theories-when-Bells-theorem-has-proved-that-local-realism-is-false https://www.quora.com/Why-do-some-crackpot-scientists-go-aft... [2] https://arxiv.org/pdf/1912.06462.pdf https://arxiv.org/pdf/1912.06462.pdf

corporate_shi11 7y ago
Bell's theorem gives us a clear path forward in understanding the universe. Local realism must be discarded.
- Simon_says 7y ago
  Realism is the axiom to give up, not locality. Just accept MWI as the current best guess and get on with your life.
  - selestify 7y ago
    There’s no evidence MWI is the best guess compared to other interpretations
    - AgentME 7y ago
      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.
      - semi-extrinsic 7y ago
        Instead it does have to specify the explicit concept of how these many worlds fork off from each other. MWI is a lot more mind-boggling if you truly think about it.
        GoblinSlayer 7y ago
        The forking obeys the Schrodinger equation. The collapse was artificially added to evade this forking that naturally follows from the equation.
      - yyyk 7y ago
        But it has no good explanation for why the Born rule applies at all. The current attempts are IMHO very unconvincing, since I see no reason why rational choice theory should apply at all. A much more detailed way of saying about the same thing as the above sentence: https://backreaction.blogspot.com/2019/09/the-trouble-with-many-worlds.html https://backreaction.blogspot.com/2019/09/the-trouble-with-m...
        lmm 7y ago
        > it has no good explanation for why the Born rule applies at all. Indeed it doesn't, but the Born rule is much smaller and simpler than the notion of collapse that other approaches rely on. > A much more detailed way of saying about the same thing as the above sentence: https://backreaction.blogspot.com/2019/09/the-trouble-with-m.. https://backreaction.blogspot.com/2019/09/the-trouble-with-m.... This post doesn't seem to understand many-worlds. There is no concept of a privileged "detector". All that many-worlds postulates is that detectors, experimenters, and anything else you might measure with obeys the normal rules of physics, and can be put into an entangled superposition just like anything else.
  - corporate_shi11 7y ago
    MWI is fashionable today, tomorrow it will be something else. Such is the case with unfalsifiable semi-mystical interpretations.
    - TeMPOraL 7y ago
      > Such is the case with unfalsifiable semi-mystical interpretations. Like Copenhagen? AFAIK, both explanations have been around for roughly the same while now, and neither seems to be going out of fashion any time soon.
    - qubex 7y ago
      MWI may remain fashionable forever in some subset of parallel future universes.
perl4ever 7y ago
I'm not sure if everything being deterministic is an abhorrent, invalid option, but I also don't see why reality has to be local. I mean, the limitation of light speed is something that exists to make a consistent theory, not something that somehow has value in itself...? My problem is probably not just a lack of math, but a lack of taste.
- trevyn 7y ago
  Agreed. I think it becomes clearer when you start to look at the human dynamics of group belief systems, and the process of changing those beliefs and consequent turmoil. The fact is, we don’t have enough evidence yet to decide one way or the other, but there is a commonly accepted interpretation that is quite strongly cemented in the minds of practicing physicists, which works well for their purposes. When challenged by a fringe group, they will naturally defend their beliefs in ways that are both scientific and human-reactionary. Being scientists, they will be open to changing beliefs given enough evidence, but being human, they will instinctively defend their existing beliefs, even if poorly supported, until sufficient evidence arrives. I suppose the perfect Bayesian physicist would hold a superposition of beliefs, and use this set to decide on the most promising allocation of research resources. Of course, having incomplete information, there is always the chance of a hidden dynamic that, to uncover, requires chance investigation of an unlikely theory. :-)
- GoblinSlayer 7y ago
  Evidence for locality is theory of relativity, which has practical applications too. Evidence against locality are vague feelings (not Bell's theorem), that have internal theoretical problems. What would be taste here?
- tsimionescu 7y ago
  > I mean, the limitation of light speed is something that exists to make a consistent theory, not something that somehow has value in itself...? The limitation of causation to a constant speed is well proven in experiments, and seems to be a fundamental aspect of the universe at large scales. If this same limitation doesn't hold at small scales then either: 1. There must be some cutoff between large scale and small scale, and small scale events can't influence large scale events. 2. Instantaneous action at a distance exists at large scales as well, and so our theories are wrong (we need a new theory to explain the observations of the speed of light etc.). This is all not to mention that we have not noticed any particle moving past the speed of light, and that we have measured the same constant speed of light at quantum levels as well (a photon measured from a moving detector has the same speed as one measured from a static detector). So that way lies nothing good. On the other hand, rejecting local realism doesn't mean that QM rejects the speed of light being constant - quantum entanglement can't carry information, so it can't produce actions at a distance. Also, note that the most common interpretation of QM is neither local nor 'real' - that is, it implies both that particles have no definite state until they are measured, and that QE propagates at infinitite speed. That is, when you fire two entangled photons, neither of the photons has any value for polarization until they are measured; however, when one is measured, it acquires a particular spin, and the other one also acquires the corresponding spin instantaneously, possibly on the other side of the galaxy. Now, one problem with all this is that it is extremely non-intuitive, and does not apply to the large-scale world (an apple is red whether I look at it or not). Related to the second issue, there is the problem of measurement: in a theory which rejects realism, the act of measurement has a fundamental physical effect, but there is no explanation for this mechanism, it is simply postulated. Note that a photon interacting with another photon is not measurment, they will each retain a superposition of states until a measurement happens.
millstone 7y ago
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 https://en.wikipedia.org/wiki/Implicate_and_explicate_order
- knzhou 7y ago
  Yes, but in order to actually explain the results of existing experiments superdeterministically, this "implicate" order must be vast. It has to link the results of spin measurements, coin flips, radioactive decays halfway across the world, and the twinkling of the light from a long-dead star, all of which are sources of apparent randomness used together in experiments. All of this has to work in concert. If that really is the right way to think about the world, then absolutely nothing of science can survive. There is no such thing as a controlled experiment.
  - ganzuul 7y ago
    Naively, superconductivity could serve as a partially closed system for experiments in this theory.
  - jcranberry 7y ago
    nonsense, that's saying that no kind of science based on probabilities could survive because it's difficult to run a deterministic experiment. if that was the case then things like climate science, atmospheric science and meteorology would be unable to exist in the first place.
comboy 7y ago
As Quora answer mentions, this paper exists because of Bell's inequality. But that answer is not convincing at all. It's a simple non-controversial fact of physics that whatever experiment you choose to perform there is some common element that influenced it all in the past. There is no true independence in the real world and you don't need superdeterminism to acknowledge that. Am I missing something?
ukj 7y ago
>this in particular just strikes me as hard to believe / failing Occam's razor Reality owes us nothing - not even simple laws of physics. Occam's razor is a pragmatic (human) bias - reality needs not adhere to it. In fact, if reality adheres to Hickam's dictum then Occam's razor is an outright error.

by themgt 7y ago

corporate_shi11 7y ago

Bell's theorem gives us a clear path forward in understanding the universe. Local realism must be discarded.

Simon_says 7y ago
Realism is the axiom to give up, not locality. Just accept MWI as the current best guess and get on with your life.
- selestify 7y ago
  There’s no evidence MWI is the best guess compared to other interpretations
  - AgentME 7y ago
    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.
    - semi-extrinsic 7y ago
      Instead it does have to specify the explicit concept of how these many worlds fork off from each other. MWI is a lot more mind-boggling if you truly think about it.
      - GoblinSlayer 7y ago
        The forking obeys the Schrodinger equation. The collapse was artificially added to evade this forking that naturally follows from the equation.
    - yyyk 7y ago
      But it has no good explanation for why the Born rule applies at all. The current attempts are IMHO very unconvincing, since I see no reason why rational choice theory should apply at all. A much more detailed way of saying about the same thing as the above sentence: https://backreaction.blogspot.com/2019/09/the-trouble-with-many-worlds.html https://backreaction.blogspot.com/2019/09/the-trouble-with-m...
      - lmm 7y ago
        > it has no good explanation for why the Born rule applies at all. Indeed it doesn't, but the Born rule is much smaller and simpler than the notion of collapse that other approaches rely on. > A much more detailed way of saying about the same thing as the above sentence: https://backreaction.blogspot.com/2019/09/the-trouble-with-m.. https://backreaction.blogspot.com/2019/09/the-trouble-with-m.... This post doesn't seem to understand many-worlds. There is no concept of a privileged "detector". All that many-worlds postulates is that detectors, experimenters, and anything else you might measure with obeys the normal rules of physics, and can be put into an entangled superposition just like anything else.
- corporate_shi11 7y ago
  MWI is fashionable today, tomorrow it will be something else. Such is the case with unfalsifiable semi-mystical interpretations.
  - TeMPOraL 7y ago
    > Such is the case with unfalsifiable semi-mystical interpretations. Like Copenhagen? AFAIK, both explanations have been around for roughly the same while now, and neither seems to be going out of fashion any time soon.
  - qubex 7y ago
    MWI may remain fashionable forever in some subset of parallel future universes.

perl4ever 7y ago

I'm not sure if everything being deterministic is an abhorrent, invalid option, but I also don't see why reality has to be local. I mean, the limitation of light speed is something that exists to make a consistent theory, not something that somehow has value in itself...? My problem is probably not just a lack of math, but a lack of taste.

trevyn 7y ago
Agreed. I think it becomes clearer when you start to look at the human dynamics of group belief systems, and the process of changing those beliefs and consequent turmoil. The fact is, we don’t have enough evidence yet to decide one way or the other, but there is a commonly accepted interpretation that is quite strongly cemented in the minds of practicing physicists, which works well for their purposes. When challenged by a fringe group, they will naturally defend their beliefs in ways that are both scientific and human-reactionary. Being scientists, they will be open to changing beliefs given enough evidence, but being human, they will instinctively defend their existing beliefs, even if poorly supported, until sufficient evidence arrives. I suppose the perfect Bayesian physicist would hold a superposition of beliefs, and use this set to decide on the most promising allocation of research resources. Of course, having incomplete information, there is always the chance of a hidden dynamic that, to uncover, requires chance investigation of an unlikely theory. :-)
GoblinSlayer 7y ago
Evidence for locality is theory of relativity, which has practical applications too. Evidence against locality are vague feelings (not Bell's theorem), that have internal theoretical problems. What would be taste here?
tsimionescu 7y ago
> I mean, the limitation of light speed is something that exists to make a consistent theory, not something that somehow has value in itself...? The limitation of causation to a constant speed is well proven in experiments, and seems to be a fundamental aspect of the universe at large scales. If this same limitation doesn't hold at small scales then either: 1. There must be some cutoff between large scale and small scale, and small scale events can't influence large scale events. 2. Instantaneous action at a distance exists at large scales as well, and so our theories are wrong (we need a new theory to explain the observations of the speed of light etc.). This is all not to mention that we have not noticed any particle moving past the speed of light, and that we have measured the same constant speed of light at quantum levels as well (a photon measured from a moving detector has the same speed as one measured from a static detector). So that way lies nothing good. On the other hand, rejecting local realism doesn't mean that QM rejects the speed of light being constant - quantum entanglement can't carry information, so it can't produce actions at a distance. Also, note that the most common interpretation of QM is neither local nor 'real' - that is, it implies both that particles have no definite state until they are measured, and that QE propagates at infinitite speed. That is, when you fire two entangled photons, neither of the photons has any value for polarization until they are measured; however, when one is measured, it acquires a particular spin, and the other one also acquires the corresponding spin instantaneously, possibly on the other side of the galaxy. Now, one problem with all this is that it is extremely non-intuitive, and does not apply to the large-scale world (an apple is red whether I look at it or not). Related to the second issue, there is the problem of measurement: in a theory which rejects realism, the act of measurement has a fundamental physical effect, but there is no explanation for this mechanism, it is simply postulated. Note that a photon interacting with another photon is not measurment, they will each retain a superposition of states until a measurement happens.

millstone 7y ago

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

knzhou 7y ago
Yes, but in order to actually explain the results of existing experiments superdeterministically, this "implicate" order must be vast. It has to link the results of spin measurements, coin flips, radioactive decays halfway across the world, and the twinkling of the light from a long-dead star, all of which are sources of apparent randomness used together in experiments. All of this has to work in concert. If that really is the right way to think about the world, then absolutely nothing of science can survive. There is no such thing as a controlled experiment.
- ganzuul 7y ago
  Naively, superconductivity could serve as a partially closed system for experiments in this theory.
- jcranberry 7y ago
  nonsense, that's saying that no kind of science based on probabilities could survive because it's difficult to run a deterministic experiment. if that was the case then things like climate science, atmospheric science and meteorology would be unable to exist in the first place.

comboy 7y ago

As Quora answer mentions, this paper exists because of Bell's inequality. But that answer is not convincing at all. It's a simple non-controversial fact of physics that whatever experiment you choose to perform there is some common element that influenced it all in the past. There is no true independence in the real world and you don't need superdeterminism to acknowledge that. Am I missing something?

ukj 7y ago

>this in particular just strikes me as hard to believe / failing Occam's razor Reality owes us nothing - not even simple laws of physics. Occam's razor is a pragmatic (human) bias - reality needs not adhere to it. In fact, if reality adheres to Hickam's dictum then Occam's razor is an outright error.