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No? At least not any more than any other theory in science. It's a mathematical model that makes predictions. When the predictions stop matching experiment,

No? At least not any more than any other theory in science. It's a mathematical model that makes predictions. When the predictions stop matching experiment, then we can throw it away.

ThomPete 11y ago
Maybe I am wrong but as far as I understand thats not really the issue here. As far as I understand there are 3 types of competing interpretations all trying to deal with the local universe vs. the non-local one and trying to explain them in a way that make sense. 1) Logically consistent, allow us to make predictions but which requires a leap of faith (Many World interpretation) 2) Mathematically correct but does not allow us to make predictions (string theory) 3) Allow us to make predictions, doesn't require leap of faith but isn't logically consistent all the way (Copenhagen interpretation) There is also a couple of outsiders like the electrical universe and plasma universe which completely ignores the idea of quantum weirdness but as far as I understand they also require some leap of faith.
- gizmo686 11y ago
  Copenhagen requires a leap of faith to accept wavefunction collapse.
  - deleted 11y ago
    [deleted]
guscost 11y ago
The difference with an interpretation like MWI is that no experiment can disprove it, even in theory. The interpretation requires that the many worlds do not interact, and unless that changes, there is no way to observe anything contradictory to the interpretation that doesn't also contradict QM. Most other famous science theories are falsifiable (I would say it is a necessary condition to qualify as science).
- pjscott 11y ago
  It's a mathematical model that makes observable predictions. It's easily falsifiable: just show that its predictions are false. Now, you could argue that there's no test to distinguish it from other interpretations of quantum mechanics, but that applies to them as well.
  - guscost 11y ago
    Which predictions of the MWI are observable? > It's a mathematical model that makes observable predictions. It sounds like you're talking about QM itself, not any interpretation.
    - Moshe_Silnorin 11y ago
      QM, itself, predicts macroscopic decoherence. Many worlds is more a prediction of QM than an interpretation.
      - guscost 11y ago
        Great way to present it, but we're still talking about a prediction that can't be tested, even in theory.
  - ThomPete 11y ago
    It makes mathematical predictions perhaps but thats not enough as far as I understand to claim that you can make predictions in any normal sense of that word. And therefore the Parent I was originally responding to at least from my understanding is claiming something thats not telling the whole story.
- Strilanc 11y ago
  > The interpretation requires that the many worlds do not interact ...What? In MWI, interactions between "worlds" is the mechanism for all the quantum effects. If they never interacted, it'd give the wrong predictions. Also, many proponents of MWI (e.g. Sean Carroll) don't think of the theory in terms of worlds at all. It's just a name that stuck. Really it's just what you get when you infer the Born rule from the unitarity postulate instead of having the Born rule as an extra postulate. An intuition pump for this idea is: you probably think photons passing the point of no return and escape our Hubble bubble continue to exist. But you'll never ever see them again, even in principle! Wouldn't a model that says they simply get deleted out of reality be strictly simpler in terms of number of entities and therefore be preferred? Assuming a rule that simply deletes parts of the wave function that decohere away from us (i.e. collapse) is pretty analogous to that ( See: http://lesswrong.com/lw/pb/belief_in_the_implied_invisible/ http://lesswrong.com/lw/pb/belief_in_the_implied_invisible/ ). Getting rid of the photon-deletion rule is analogous to accepting MWI (though I don't mean to imply it's the only game in town).

No? At least not any more than any other theory in science. It's a mathematical model that makes predictions. When the predictions stop matching experiment, then we can throw it away.

ThomPete 11y ago

Maybe I am wrong but as far as I understand thats not really the issue here. As far as I understand there are 3 types of competing interpretations all trying to deal with the local universe vs. the non-local one and trying to explain them in a way that make sense. 1) Logically consistent, allow us to make predictions but which requires a leap of faith (Many World interpretation) 2) Mathematically correct but does not allow us to make predictions (string theory) 3) Allow us to make predictions, doesn't require leap of faith but isn't logically consistent all the way (Copenhagen interpretation) There is also a couple of outsiders like the electrical universe and plasma universe which completely ignores the idea of quantum weirdness but as far as I understand they also require some leap of faith.

gizmo686 11y ago
Copenhagen requires a leap of faith to accept wavefunction collapse.
- deleted 11y ago
  [deleted]

guscost 11y ago

The difference with an interpretation like MWI is that no experiment can disprove it, even in theory. The interpretation requires that the many worlds do not interact, and unless that changes, there is no way to observe anything contradictory to the interpretation that doesn't also contradict QM. Most other famous science theories are falsifiable (I would say it is a necessary condition to qualify as science).

pjscott 11y ago
It's a mathematical model that makes observable predictions. It's easily falsifiable: just show that its predictions are false. Now, you could argue that there's no test to distinguish it from other interpretations of quantum mechanics, but that applies to them as well.
- guscost 11y ago
  Which predictions of the MWI are observable? > It's a mathematical model that makes observable predictions. It sounds like you're talking about QM itself, not any interpretation.
  - Moshe_Silnorin 11y ago
    QM, itself, predicts macroscopic decoherence. Many worlds is more a prediction of QM than an interpretation.
    - guscost 11y ago
      Great way to present it, but we're still talking about a prediction that can't be tested, even in theory.
- ThomPete 11y ago
  It makes mathematical predictions perhaps but thats not enough as far as I understand to claim that you can make predictions in any normal sense of that word. And therefore the Parent I was originally responding to at least from my understanding is claiming something thats not telling the whole story.
Strilanc 11y ago
> The interpretation requires that the many worlds do not interact ...What? In MWI, interactions between "worlds" is the mechanism for all the quantum effects. If they never interacted, it'd give the wrong predictions. Also, many proponents of MWI (e.g. Sean Carroll) don't think of the theory in terms of worlds at all. It's just a name that stuck. Really it's just what you get when you infer the Born rule from the unitarity postulate instead of having the Born rule as an extra postulate. An intuition pump for this idea is: you probably think photons passing the point of no return and escape our Hubble bubble continue to exist. But you'll never ever see them again, even in principle! Wouldn't a model that says they simply get deleted out of reality be strictly simpler in terms of number of entities and therefore be preferred? Assuming a rule that simply deletes parts of the wave function that decohere away from us (i.e. collapse) is pretty analogous to that ( See: http://lesswrong.com/lw/pb/belief_in_the_implied_invisible/ http://lesswrong.com/lw/pb/belief_in_the_implied_invisible/ ). Getting rid of the photon-deletion rule is analogous to accepting MWI (though I don't mean to imply it's the only game in town).