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Not exactly - they expressed an assumption that is too strong in this explanation. The assumption that is needed is only that measurement choice is not correlat

Not exactly - they expressed an assumption that is too strong in this explanation. The assumption that is needed is only that measurement choice is not correlated with the generation of the particles themselves - not that it is not determined by past history. That is why there was a lot of interest in doing cosmic Bell-like experiments: it is very hard to define a mechanism whereby the hidden property of the particle that left the quasar many billions of years ago also determined that Alice and Bob would set their apparatuses to measure these specific angles today. Theoretically this doesn't rule out the possibility, but it does mean at least that the theory would have to be significantly non-intuitive in its own right (whereas if Bell-like inequalities only happened for small-scale experiment, the theory that explained them could have been very simple indeed - such as some new wave that affected the measurement apparatus or some aspect of how we choose measurement angles).

zmgsabst 4y ago
But isn’t the Bohm model that all particles are weakly correlated? — eg, there’s some kind of “whole universe” quasi-particle from the inflationary period? The exact alternative to non-determinism is super-macro quasiparticles/correlations. Which this seems to assume away.
- simiones 4y ago
  There is a difference between proving that all events have share a causal relationship (which is an assumption of every mechanistic model of the universe), and proving that that causal relationship between distantly related events determines very precise restrictions that happen to match the predictions of QM. To take it to a more human realm - we can all agree that if Caesar weren't killed by Brutus, the world would be so different that it's very unlikely both Biden and Putin would be presidents of their respective countries today - this is an almost trivially true statement I would argue. However, if we observe that at every public appearance Biden and Putin wear costumes of the same color, it's very hard to come up with a theory that explains that their choice of costume is caused by Caesar killing Brutus. And this is essentially what the super-determinism argument gets at: the same thing that caused this photon emitted by a quark to be polarized up 1 billion years after the Big Bang also caused Alice to measure the polarization of that particle along 30 degrees 13 billion years after the Big Bang.
  - zmgsabst 4y ago
    But they’re carrying shared quantum state — why would it be surprising their actions were correlated? Eg, that particle being a particular state is correlated to Alice picking a particular measurement because the total system must maintain that quantum number. The particle which emitted the photon and the particles which give way to Alice have carried that information since the inflationary period — and so the photon and Alice share that correlation now. The conclusion seems to be “the correlation must be at least this old!” — but that’s exactly the claim being made. So I’m not sure I understand the problem for Bohm-derived models.
    - simiones 4y ago
      Look at the difficulty of creating a quantum computer if you really think that it's plausible shared quantum state would survive for a few billion years and interactions with a whole galaxy. Also, not sure what particular quantum number you think would have to be conserved and would influence Alice's decision of which way to configure her measurement apparatus - this would definitely require some new quantum property.

zmgsabst 4y ago

But isn’t the Bohm model that all particles are weakly correlated? — eg, there’s some kind of “whole universe” quasi-particle from the inflationary period? The exact alternative to non-determinism is super-macro quasiparticles/correlations. Which this seems to assume away.

simiones 4y ago
There is a difference between proving that all events have share a causal relationship (which is an assumption of every mechanistic model of the universe), and proving that that causal relationship between distantly related events determines very precise restrictions that happen to match the predictions of QM. To take it to a more human realm - we can all agree that if Caesar weren't killed by Brutus, the world would be so different that it's very unlikely both Biden and Putin would be presidents of their respective countries today - this is an almost trivially true statement I would argue. However, if we observe that at every public appearance Biden and Putin wear costumes of the same color, it's very hard to come up with a theory that explains that their choice of costume is caused by Caesar killing Brutus. And this is essentially what the super-determinism argument gets at: the same thing that caused this photon emitted by a quark to be polarized up 1 billion years after the Big Bang also caused Alice to measure the polarization of that particle along 30 degrees 13 billion years after the Big Bang.
- zmgsabst 4y ago
  But they’re carrying shared quantum state — why would it be surprising their actions were correlated? Eg, that particle being a particular state is correlated to Alice picking a particular measurement because the total system must maintain that quantum number. The particle which emitted the photon and the particles which give way to Alice have carried that information since the inflationary period — and so the photon and Alice share that correlation now. The conclusion seems to be “the correlation must be at least this old!” — but that’s exactly the claim being made. So I’m not sure I understand the problem for Bohm-derived models.
  - simiones 4y ago
    Look at the difficulty of creating a quantum computer if you really think that it's plausible shared quantum state would survive for a few billion years and interactions with a whole galaxy. Also, not sure what particular quantum number you think would have to be conserved and would influence Alice's decision of which way to configure her measurement apparatus - this would definitely require some new quantum property.