5 ms·

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

by Simon_says 7y ago

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.
      - yyyk 7y ago
        >Indeed it doesn't, but the Born rule is much smaller and simpler than the notion of collapse that other approaches rely on. First, not all of the other approaches have a collapse. e.g. Bohm and a few lesser known others don't have it. Second, it's not clear Born is 'smaller and simpler' than the collapse of some other interpretations. e.g. in QBism collapse arises naturally from the theory and it would be weird if collapse didn't happen. " This post doesn't seem to understand many-worlds... anything else you might measure with obeys the normal rules of physics" Her point is that what MWI tries to derive everything from the Schrödinger equation alone, but it still needs to solve its equivalent of the measurement problem (why can we only get certain results on the evolution of this branch?), but that can't be done since Schrödinger is linear and the equivalent problem is not.
        lmm 7y ago
        > e.g. Bohm and a few lesser known others don't have it. Bohm is just MWI with a bunch of extra epicycles. > Second, it's not clear Born is 'smaller and simpler' than the collapse of some other interpretations. e.g. in QBism collapse arises naturally from the theory and it would be weird if collapse didn't happen. I'd be interested in hearing more, but from a quick look I'd argue that the notion of an agent who should evaluate subjective probabilities is more complex than objective probability numbers. > Her point is that what MWI tries to derive everything from the Schrödinger equation alone, but it still needs to solve its equivalent of the measurement problem (why can we only get certain results on the evolution of this branch?) That's not true though. The branching behaviour is inherent in the Schrödinger equation.
- kanzenryu2 7y ago
  You may find this interesting https://www.lesswrong.com/posts/9cgBF6BQ2TRB3Hy4E/and-the-winner-is-many-worlds https://www.lesswrong.com/posts/9cgBF6BQ2TRB3Hy4E/and-the-wi...
  - trevyn 7y ago
    Wait, is MWI compatible with superdeterminism? That is, the sequence above seems to show that MWI is an effective way to calculate, but does not actually rule out superdeterminism underneath it — just like ordinary quantum mechanics is an effective way to calculate in certain domains of applicability but cannot effectively claim to be the “underlying reality”.
    - trenchgun 7y ago
      This seems to be the correct take. Edit. Based on Hossfelder's & Palmer's paper I have transitioned from MWI to superdeterminism. I encourage all to read the paper. Very beautiful clarity of thought, I say.
    - GoblinSlayer 7y ago
      All theories are compatible with undetectable additions, but that's kinda whole point: MWI doesn't need them and works fine without them. But I believe superdeterminism has single world, so I don't see how it can emulate MWI.
      - mikk14 7y ago
        I just had a funny thought. I don't know if it makes any sense, but it's funny to think about it. This is all made with my tongue firmly in my cheek, I don't know nearly enough about the topic to have any sort of confidence on what follows, so hold your downvotes :-) Let's assume MWI is correct. This means that, as far as I understand, the Schrodinger equation imposes that for each quantum event there is a forking in two worlds: one per possible state (cat alive/dead). The implication is that there are (infinitely) many world branches that go from the beginning to the end of time. Since there is no collapse, each of these branches must be superdeterministic by definition: that's how we picked the branch, we identified a sequence of forks in the Schrodinger equation by picking the result. "I" can live only in one of these branches: there are infinitely many "I"s, but the one I am in right now is one of them. I'll be in my branch until I die (many other "I"s will branch off me). Since every "I" lives on a branch, every "I" experiences the universe as superdeterministic. Thus, if we assume MWI is correct, the result for any possible "I" is indistinguishable from superdeterminism. It gets funnier. If what I said it is true, MWI and superdeterminism are indistinguishable. However, one presupposes the creation of branches, while the other does not. Thus one is more parsimonious than the other, and should be preferred. Or, in other worlds, by assuming MWI is true, we prove that it is false and that superdeterminism is true.
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.

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.
    - yyyk 7y ago
      >Indeed it doesn't, but the Born rule is much smaller and simpler than the notion of collapse that other approaches rely on. First, not all of the other approaches have a collapse. e.g. Bohm and a few lesser known others don't have it. Second, it's not clear Born is 'smaller and simpler' than the collapse of some other interpretations. e.g. in QBism collapse arises naturally from the theory and it would be weird if collapse didn't happen. " This post doesn't seem to understand many-worlds... anything else you might measure with obeys the normal rules of physics" Her point is that what MWI tries to derive everything from the Schrödinger equation alone, but it still needs to solve its equivalent of the measurement problem (why can we only get certain results on the evolution of this branch?), but that can't be done since Schrödinger is linear and the equivalent problem is not.
      - lmm 7y ago
        > e.g. Bohm and a few lesser known others don't have it. Bohm is just MWI with a bunch of extra epicycles. > Second, it's not clear Born is 'smaller and simpler' than the collapse of some other interpretations. e.g. in QBism collapse arises naturally from the theory and it would be weird if collapse didn't happen. I'd be interested in hearing more, but from a quick look I'd argue that the notion of an agent who should evaluate subjective probabilities is more complex than objective probability numbers. > Her point is that what MWI tries to derive everything from the Schrödinger equation alone, but it still needs to solve its equivalent of the measurement problem (why can we only get certain results on the evolution of this branch?) That's not true though. The branching behaviour is inherent in the Schrödinger equation.
kanzenryu2 7y ago
You may find this interesting https://www.lesswrong.com/posts/9cgBF6BQ2TRB3Hy4E/and-the-winner-is-many-worlds https://www.lesswrong.com/posts/9cgBF6BQ2TRB3Hy4E/and-the-wi...
- trevyn 7y ago
  Wait, is MWI compatible with superdeterminism? That is, the sequence above seems to show that MWI is an effective way to calculate, but does not actually rule out superdeterminism underneath it — just like ordinary quantum mechanics is an effective way to calculate in certain domains of applicability but cannot effectively claim to be the “underlying reality”.
  - trenchgun 7y ago
    This seems to be the correct take. Edit. Based on Hossfelder's & Palmer's paper I have transitioned from MWI to superdeterminism. I encourage all to read the paper. Very beautiful clarity of thought, I say.
  - GoblinSlayer 7y ago
    All theories are compatible with undetectable additions, but that's kinda whole point: MWI doesn't need them and works fine without them. But I believe superdeterminism has single world, so I don't see how it can emulate MWI.
    - mikk14 7y ago
      I just had a funny thought. I don't know if it makes any sense, but it's funny to think about it. This is all made with my tongue firmly in my cheek, I don't know nearly enough about the topic to have any sort of confidence on what follows, so hold your downvotes :-) Let's assume MWI is correct. This means that, as far as I understand, the Schrodinger equation imposes that for each quantum event there is a forking in two worlds: one per possible state (cat alive/dead). The implication is that there are (infinitely) many world branches that go from the beginning to the end of time. Since there is no collapse, each of these branches must be superdeterministic by definition: that's how we picked the branch, we identified a sequence of forks in the Schrodinger equation by picking the result. "I" can live only in one of these branches: there are infinitely many "I"s, but the one I am in right now is one of them. I'll be in my branch until I die (many other "I"s will branch off me). Since every "I" lives on a branch, every "I" experiences the universe as superdeterministic. Thus, if we assume MWI is correct, the result for any possible "I" is indistinguishable from superdeterminism. It gets funnier. If what I said it is true, MWI and superdeterminism are indistinguishable. However, one presupposes the creation of branches, while the other does not. Thus one is more parsimonious than the other, and should be preferred. Or, in other worlds, by assuming MWI is true, we prove that it is false and that superdeterminism is true.

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.