I think your criticism here is a bit shortsighted. Just look at the longer passage that I quoted in the OP. It directly deals with some ramifications if you hold that the collapse of the wavefunction is real, namely spooky action at a distance becomes an even worse problem. It’s even harder to give an account for the physical quantum states separated by vast distance being more than just classically correlated. In the very next paragraph they mention that in interpretations in which no actual collapse has to happen, their result gives further credence to the idea that distinct quantum states are distinct physically real things.
It’s as if you just want me personally to be wrong, because both the OP and the Leifer quote above deal with ramifications in the with-collapse cases vs. ramifications in the without-collapse cases. I don’t see how you can say that choice to offer the quote means that I do not understand it. I also don’t see how you can claim that Many Worlds is unrelated when the linked paper itself mentions ramifications for that case.
I didn’t claim that this conclusively proves anything about collapse or ontological measurement, only that the ramifications do add something above and beyond Bell’s theorem. And I stick by that.
Just look at the longer passage that I quoted in the OP. It directly deals with some ramifications if you hold that the collapse of the wavefunction is real, namely spooky action at a distance becomes an even worse problem.
There is more than one interpretation of the passage you quoted, and I think a more neutral interpretation is more likely. In the first paragraph they highlight interpretations with collapse, explore the implications for interpretations with collapse, and point out an unintuitive consequence:“This is especially mysterious when two entangled systems are at separate locations, and measurement of one leads to an instantaneous collapse of the quantum state of the other.”
In the second paragraph they highlight interpretations without collapse, explore the implications for interpretations without collapse, and point out an unintuitive consequence:“But if the quantum state is a physical property of the system and apparatus, it is hard to avoid the conclusion that each marcoscopically different component has a direct counterpart in reality.”
The paragraphs have the same structure. Ramifications are mentioned for both cases. So when you say “I also don’t see how you can claim that Many Worlds is unrelated when the linked paper itself mentions ramifications for that case,” it seems to me like you’re reading asymmetrically. The authors appear to have simply explored the implications of their theorem for interpretations with and without collapse—and of course there were unintuitive bits for both, because it’s quantum mechanics.
There is more than one interpretation of the passage you quoted, and I think a more neutral interpretation is more likely.
This is a good point. I should say, “One possible interpretation is...”, but in either case I don’t think my reliance on direct quotes to try to illustrate this stronger interpretation that I advocate should qualify as failure to understand on my part. As I read the second paragraph, it seems to straightforwardly apply to Many Worlds in an important way, but I am totally willing to accept the point of view that the implications are less salient. It was just that your original comment:
Bringing up many-worlds in this article is unnecessary.
seemed unproductive to me. In what sense is it unnecessary? Unnecessary for understanding the original result? Sure… but I didn’t bring up the original result for its own sake, only to discuss implications for wave collapse.
Although there is no direct effect on the state of the evidence, I guess you’re right that there can be an indirect effect. For example, ‘collapse’ could look better than ‘no-collapse’ given wavefunction non-realism, but ‘no-collapse’ could look better than ‘collapse’ given wavefunction realism. In this case, changing our position on wavefunction realism would change the opinion on collapse vs. no-collapse.
But this effect only occurs to the extent that people already believe in the things disproved (or called into question). People who took this “statistical sort-of-nonrealism” model seriously, rather than as merely an interesting idea, are pretty rare even in the physics world*. And here on LW? Fuggedaboutit.
* I’ve never run into one, and they never came up when I talked to someone who’s working on this kind of stuff—mostly focused on the neo-Copenhagenists, to use Leifer’s term, and testing some specific sorts of collapse.
I think your criticism here is a bit shortsighted. Just look at the longer passage that I quoted in the OP. It directly deals with some ramifications if you hold that the collapse of the wavefunction is real, namely spooky action at a distance becomes an even worse problem. It’s even harder to give an account for the physical quantum states separated by vast distance being more than just classically correlated. In the very next paragraph they mention that in interpretations in which no actual collapse has to happen, their result gives further credence to the idea that distinct quantum states are distinct physically real things.
It’s as if you just want me personally to be wrong, because both the OP and the Leifer quote above deal with ramifications in the with-collapse cases vs. ramifications in the without-collapse cases. I don’t see how you can say that choice to offer the quote means that I do not understand it. I also don’t see how you can claim that Many Worlds is unrelated when the linked paper itself mentions ramifications for that case.
I didn’t claim that this conclusively proves anything about collapse or ontological measurement, only that the ramifications do add something above and beyond Bell’s theorem. And I stick by that.
There is more than one interpretation of the passage you quoted, and I think a more neutral interpretation is more likely. In the first paragraph they highlight interpretations with collapse, explore the implications for interpretations with collapse, and point out an unintuitive consequence: “This is especially mysterious when two entangled systems are at separate locations, and measurement of one leads to an instantaneous collapse of the quantum state of the other.”
In the second paragraph they highlight interpretations without collapse, explore the implications for interpretations without collapse, and point out an unintuitive consequence: “But if the quantum state is a physical property of the system and apparatus, it is hard to avoid the conclusion that each marcoscopically different component has a direct counterpart in reality.”
The paragraphs have the same structure. Ramifications are mentioned for both cases. So when you say “I also don’t see how you can claim that Many Worlds is unrelated when the linked paper itself mentions ramifications for that case,” it seems to me like you’re reading asymmetrically. The authors appear to have simply explored the implications of their theorem for interpretations with and without collapse—and of course there were unintuitive bits for both, because it’s quantum mechanics.
This is a good point. I should say, “One possible interpretation is...”, but in either case I don’t think my reliance on direct quotes to try to illustrate this stronger interpretation that I advocate should qualify as failure to understand on my part. As I read the second paragraph, it seems to straightforwardly apply to Many Worlds in an important way, but I am totally willing to accept the point of view that the implications are less salient. It was just that your original comment:
seemed unproductive to me. In what sense is it unnecessary? Unnecessary for understanding the original result? Sure… but I didn’t bring up the original result for its own sake, only to discuss implications for wave collapse.
Although there is no direct effect on the state of the evidence, I guess you’re right that there can be an indirect effect. For example, ‘collapse’ could look better than ‘no-collapse’ given wavefunction non-realism, but ‘no-collapse’ could look better than ‘collapse’ given wavefunction realism. In this case, changing our position on wavefunction realism would change the opinion on collapse vs. no-collapse.
But this effect only occurs to the extent that people already believe in the things disproved (or called into question). People who took this “statistical sort-of-nonrealism” model seriously, rather than as merely an interesting idea, are pretty rare even in the physics world*. And here on LW? Fuggedaboutit.
* I’ve never run into one, and they never came up when I talked to someone who’s working on this kind of stuff—mostly focused on the neo-Copenhagenists, to use Leifer’s term, and testing some specific sorts of collapse.