What single-world interpretation basically say to fit MWI: All but one world are eliminated by a magic faster than light non-local time-asymmetric acausal collapser-device.
So far MWI sounds like the most reasonable interpretation to me. And from what I have read I can tell that the sentence—“despite the lack of testable predictions differing from the Copenhagen interpretation”—is not crucial in favoring MWI over other interpretations.
Of course I am not able to judge that MWI is the correct interpretation but, given my current epistemic state, of all interpretations it is the most likely to be correct. For one it sounds reasonable, secondly Yudkowsky’s judgement has a considerable weight here. I have no reason to suspect that it would benefit him to favor MWI over other interpretations. Yet there is much evidence that suggests that he is highly intelligent and that he is able to judge what is the correct interpretation given all evidence a non-physicists can take into account.
Edit: “[...] is not correct, or at least not crucial.” now reads “[...] is not crucial in favoring MWI over other interpretations.”
And from what I have read I can tell that the sentence—“despite the lack of testable predictions differing from the Copenhagen interpretation”—is not correct, or at least not crucial.
It is correct, and it is crucial in the sense that most philosophy of science would insist that differing testable predictions is all that would favor one theory over another.
But other concerns (the Bayesian interpretation of Occam’s Razor (or any interpretation, probably)) make MWI preferred.
An interpretation of Occam’s Razor that placed all emphasis on space complexity would clearly favor the Copenhagen interpretation over the MW interpretation. Of course, it would also favor “you’re living in a holodeck” over “there’s an actual universe out there”, so it’s a poor formulation in it’s simplest form… but it’s not obvious (to me, anyway) that space complexity should count for nothing at all, and if it counts for “enough” (whatever that is, for the particular rival interpretation) MWI loses.
What particular gold-standard “Occam’s razor” are you adhering to, then? It seems to fit well with “entities must not be multiplied beyond necessity” and “pluralities must never be posited without necessity”.
Note that I’m not saying there is no gold-standard “Occam’s razor” to which we should be adhering (in terms of denotation of the term or more generally); I’m just unaware of an interpretaton that clearly lays out how “entities” or “assumptions” are counted, or how the complexity of a hypothesis is otherwise measured, which is clearly “the canonical Occam’s razor” as opposed to having some other name. If there is one, by all means please make me aware!
Is there anything in particular that leads you to claim Minimum Description Length is the only legitimate claimaint to the title “Occam’s razor”? It was introduced much later, and the wikipedia article claims it is “a forumlation of Occam’s razor”.
Certainly, William of Occam wasn’t dealing in terms of information compression.
The answer seems circular: because it works. The experience of people using Occam’s razor (e.g. scientists) find MDL to be more likely to lead to correct answers than any other formulation.
I don’t see that that makes other formulations “not Occam’s razor”, it just makes them less useful attempts at formalizing Occam’s razor. If an alternative formalization was found to work better, it would not be MDL—would MDL cease to be “Occam’s razor”? Or would the new, better formalization “not be Occam’s razor”? Of the latter, by what metric, since the new one “works better”?
For the record, I certainly agree that “space complexity alone” is a poor metric. I just don’t see that it should clearly be excluded entirely. I’m generally happy to exclude it on the grounds of parsimony, but this whole subthread was “How could MWI not be the most reasonable choice...?”
There’s an intent behind Occam’s razor. When Einstein improved on Newton’s gravity, gravity itself didn’t change. Rather, our understanding of gravity was improved by a better model. We could say though that Newton’s model is not gravity because we have found instances where gravity does not behave the way Newton predicted.
Underlying Occam’s razor is the simple idea that we should prefer simple ideas. Over time we have found ways to formalize this statement in ways that are universally applicable. These formalizations are getting closer and closer to what Occam’s razor is.
I see, I went too far in asserting something about MWI, as I am not able to discuss this in more detail. I’ll edit my orginal comments.
Edit—First comment: “[...] by what I have glimpsed this is just wrong.” now reads “[...] by what I have glimpsed this is not the crucial point that distinguishes MWI from other interpretations.”
Edit—Second comment: “[...] is not correct, or at least not crucial.” now reads “[...] is not crucial in favoring MWI over other interpretations.”
The problem isn’t that you asserted something about MWI—I’m not discussing the MWI itself here.
It’s rather that you defended something before you knew what it was that you were defending, and attacked people on their knowledge of the facts before you knew what the facts actually were.
Then once you got more informed about it, you immediately changed the form of the defense while maintaining the same judgment. (Previously it was “Bad critics who falsely claim Eliezer has judged MWI to be correct” now it’s “Bad critics who correctly claim Eliezer has judged MWI to be correct, but they badly don’t share that conclusion”)
This all is evidence (not proof, mind you) of strong bias.
Ofcourse you may have legitimately changed your mind about MWI, and legimitately moved from a wrongful criticism of the critics on their knowledge of facts to a rightful criticism of their judgment.
I’m also commenting on the blog of Neal Asher, a science fiction author I read. I have no problem making fun of his climate change skepticism although I doubt that any amateur, even on Less Wrong, would have the time to conclude that it is obviously correct. Yet I do not doubt it for the same reasons I do not doubt MWI:
There is no benefit in proclaiming the correctness of MWI (at least for Yudkowsky).
The argument used against MWI fails the argument used in favor of MWI on Less Wrong.
The person who proclaims the correctness of MWI is an expert when it comes to beliefs.
It’s the same with climate change. People saying—“look how cold it is in Europe again, that’s supposed to be global warming?!”—are, given my current state of knowledge, not even wrong. Not only will there be low-temperature records even given global warming (outliers), but global warming will also cause Europe to get colder on average. Do I know that this is correct? Nope, but I do trust the experts as I do not see that a global conspiracy is feasible and would make sense. It doesn’t benefit anyone either.
You are correct that I should stay away from calling people wrong on details when I’m not ready to get into the details. Maybe those people who wrote that entry are doing research on foundational physics, I doubt it though (writing style etc.).
I’m not sure about the details of your comment. I just changed my comment regarding the claim that there are testable predictions regarding MWI (although there are people on LW and elsewhere who claim this to be the case). As people started challenging me on that point I just retreated to not get into a discussion I can’t possible participate in. I did not change my mind about MWI in general. I just shortened my argument from MWI making testable predictions and being correct irrespective of testable predictions to the latter. That is, MWI is an implication of a theory that is more precise in its predictions, yet simpler, as the one necessary to conclude other interpretations.
My mistake was that I went to far. I read the Wiki entry and thought I’d write down my thoughts on every point. That point was behind my expertise indeed.
I haven’t seen any proof (stronger than “it seems like it”) that MWI is strictly simpler to describe. One good reason to prefer it is that it is nice and continuous, and all our other scientific theories are nice and continuous—sort of a meta-science argument.
In layman’s terms (to the best of my understanding), the proof is:
Copenhagen interpretation is “there is wave propagation and then collapse” and thus requires a description of how collapse happens. MWI is “there is wave propagation”, and thus has fewer rules, and thus is simpler (in that sense).
I agree denotatively—I don’t think the Copenhagen interpretation provides this description.
I am not sure what I do connotatively, as I am not sure what the connotations are meant to be. It would mean that quantum theory is less complete than it is if MWI is correct, but I’m not sure whether that’s a correct objection or not (and have less idea whether you intended to express it as such).
Correct. Yet I have read some subsequent discussions about that topic (MWI) and also watched this talk:
I also read Decoherence is Simple and Decoherence is Falsifiable and Testable.
So far MWI sounds like the most reasonable interpretation to me. And from what I have read I can tell that the sentence—“despite the lack of testable predictions differing from the Copenhagen interpretation”—is not crucial in favoring MWI over other interpretations.
Of course I am not able to judge that MWI is the correct interpretation but, given my current epistemic state, of all interpretations it is the most likely to be correct. For one it sounds reasonable, secondly Yudkowsky’s judgement has a considerable weight here. I have no reason to suspect that it would benefit him to favor MWI over other interpretations. Yet there is much evidence that suggests that he is highly intelligent and that he is able to judge what is the correct interpretation given all evidence a non-physicists can take into account.
Edit: “[...] is not correct, or at least not crucial.” now reads “[...] is not crucial in favoring MWI over other interpretations.”
It is correct, and it is crucial in the sense that most philosophy of science would insist that differing testable predictions is all that would favor one theory over another.
But other concerns (the Bayesian interpretation of Occam’s Razor (or any interpretation, probably)) make MWI preferred.
An interpretation of Occam’s Razor that placed all emphasis on space complexity would clearly favor the Copenhagen interpretation over the MW interpretation. Of course, it would also favor “you’re living in a holodeck” over “there’s an actual universe out there”, so it’s a poor formulation in it’s simplest form… but it’s not obvious (to me, anyway) that space complexity should count for nothing at all, and if it counts for “enough” (whatever that is, for the particular rival interpretation) MWI loses.
That would not be Occam’s razor...
What particular gold-standard “Occam’s razor” are you adhering to, then? It seems to fit well with “entities must not be multiplied beyond necessity” and “pluralities must never be posited without necessity”.
Note that I’m not saying there is no gold-standard “Occam’s razor” to which we should be adhering (in terms of denotation of the term or more generally); I’m just unaware of an interpretaton that clearly lays out how “entities” or “assumptions” are counted, or how the complexity of a hypothesis is otherwise measured, which is clearly “the canonical Occam’s razor” as opposed to having some other name. If there is one, by all means please make me aware!
Minimum description length.
The MWI requires fewer rules than Copenhagen, and therefore its description is smaller, and therefore it is the strictly simpler theory.
Is there anything in particular that leads you to claim Minimum Description Length is the only legitimate claimaint to the title “Occam’s razor”? It was introduced much later, and the wikipedia article claims it is “a forumlation of Occam’s razor”.
Certainly, William of Occam wasn’t dealing in terms of information compression.
The answer seems circular: because it works. The experience of people using Occam’s razor (e.g. scientists) find MDL to be more likely to lead to correct answers than any other formulation.
I don’t see that that makes other formulations “not Occam’s razor”, it just makes them less useful attempts at formalizing Occam’s razor. If an alternative formalization was found to work better, it would not be MDL—would MDL cease to be “Occam’s razor”? Or would the new, better formalization “not be Occam’s razor”? Of the latter, by what metric, since the new one “works better”?
For the record, I certainly agree that “space complexity alone” is a poor metric. I just don’t see that it should clearly be excluded entirely. I’m generally happy to exclude it on the grounds of parsimony, but this whole subthread was “How could MWI not be the most reasonable choice...?”
There’s an intent behind Occam’s razor. When Einstein improved on Newton’s gravity, gravity itself didn’t change. Rather, our understanding of gravity was improved by a better model. We could say though that Newton’s model is not gravity because we have found instances where gravity does not behave the way Newton predicted.
Underlying Occam’s razor is the simple idea that we should prefer simple ideas. Over time we have found ways to formalize this statement in ways that are universally applicable. These formalizations are getting closer and closer to what Occam’s razor is.
I’ll accept that.
I see, I went too far in asserting something about MWI, as I am not able to discuss this in more detail. I’ll edit my orginal comments.
Edit—First comment: “[...] by what I have glimpsed this is just wrong.” now reads “[...] by what I have glimpsed this is not the crucial point that distinguishes MWI from other interpretations.”
Edit—Second comment: “[...] is not correct, or at least not crucial.” now reads “[...] is not crucial in favoring MWI over other interpretations.”
The problem isn’t that you asserted something about MWI—I’m not discussing the MWI itself here.
It’s rather that you defended something before you knew what it was that you were defending, and attacked people on their knowledge of the facts before you knew what the facts actually were.
Then once you got more informed about it, you immediately changed the form of the defense while maintaining the same judgment. (Previously it was “Bad critics who falsely claim Eliezer has judged MWI to be correct” now it’s “Bad critics who correctly claim Eliezer has judged MWI to be correct, but they badly don’t share that conclusion”)
This all is evidence (not proof, mind you) of strong bias.
Ofcourse you may have legitimately changed your mind about MWI, and legimitately moved from a wrongful criticism of the critics on their knowledge of facts to a rightful criticism of their judgment.
I’m also commenting on the blog of Neal Asher, a science fiction author I read. I have no problem making fun of his climate change skepticism although I doubt that any amateur, even on Less Wrong, would have the time to conclude that it is obviously correct. Yet I do not doubt it for the same reasons I do not doubt MWI:
There is no benefit in proclaiming the correctness of MWI (at least for Yudkowsky).
The argument used against MWI fails the argument used in favor of MWI on Less Wrong.
The person who proclaims the correctness of MWI is an expert when it comes to beliefs.
It’s the same with climate change. People saying—“look how cold it is in Europe again, that’s supposed to be global warming?!”—are, given my current state of knowledge, not even wrong. Not only will there be low-temperature records even given global warming (outliers), but global warming will also cause Europe to get colder on average. Do I know that this is correct? Nope, but I do trust the experts as I do not see that a global conspiracy is feasible and would make sense. It doesn’t benefit anyone either.
You are correct that I should stay away from calling people wrong on details when I’m not ready to get into the details. Maybe those people who wrote that entry are doing research on foundational physics, I doubt it though (writing style etc.).
I’m not sure about the details of your comment. I just changed my comment regarding the claim that there are testable predictions regarding MWI (although there are people on LW and elsewhere who claim this to be the case). As people started challenging me on that point I just retreated to not get into a discussion I can’t possible participate in. I did not change my mind about MWI in general. I just shortened my argument from MWI making testable predictions and being correct irrespective of testable predictions to the latter. That is, MWI is an implication of a theory that is more precise in its predictions, yet simpler, as the one necessary to conclude other interpretations.
My mistake was that I went to far. I read the Wiki entry and thought I’d write down my thoughts on every point. That point was behind my expertise indeed.
I haven’t seen any proof (stronger than “it seems like it”) that MWI is strictly simpler to describe. One good reason to prefer it is that it is nice and continuous, and all our other scientific theories are nice and continuous—sort of a meta-science argument.
In layman’s terms (to the best of my understanding), the proof is:
Copenhagen interpretation is “there is wave propagation and then collapse” and thus requires a description of how collapse happens. MWI is “there is wave propagation”, and thus has fewer rules, and thus is simpler (in that sense).
… which it doesn’t provide.
I agree denotatively—I don’t think the Copenhagen interpretation provides this description.
I am not sure what I do connotatively, as I am not sure what the connotations are meant to be. It would mean that quantum theory is less complete than it is if MWI is correct, but I’m not sure whether that’s a correct objection or not (and have less idea whether you intended to express it as such).