4 ms·

>The basic idea is that most multiverse notions arise naturally out of lower level mechanisms. I think this is the part I don't understand. I have heard no evi

by Veelox 9y ago

>The basic idea is that most multiverse notions arise naturally out of lower level mechanisms. I think this is the part I don't understand. I have heard no evidence-based explanation for what lower level mechanisms cause our universe that imply a multiverse. >Say all of our experiments are explained by Theory X. Then positing Thoery X + God is a model with strictly more moving parts and equal explanatory power as Theory X alone. In pricipal I agree with you. In this case I think we disagree. In my mental model, Theory X in this case is the multiverse. At which point you say X + God is more complicated and I agree. I think instead of X + God as the explanation it should instead just be God. In which case I don't see an objective way of saying if Occam's razor would favor multiverse or God.

xelxebar 9y ago
> I have heard no evidence-based explanation for what lower level mechanisms cause our universe that imply a multiverse. The example I have in mind is the Everettian interpretation of QM. Formally, we have a Hilbert space and decoherence. We can interpret decohered regions in the Hilbert space as separate universes. These mechanics are an artifact of the mathematical formalism. Interestingly, the Copenhagen "interpretation" would get ruled out by Occam's Razor since it adds the notion of wave collapse on top of the formalism without experiment being able to differentiate between the two. > I think instead of X + God as the explanation it should instead just be God. If that works for your needs, then more power to you. We can also jump a meta-level with Occam's Razor though. Say we take a firm stance on only wanting to keep around models that are constrained by scientific experiment. Then we need, say, the Standard Model and General Relativity, but I'm not sure the God Did It model would survive said filter. For scientific progress (i.e. the cooperative human effort of science), such a hard-nosed approach seems to have worked unreasonably well so far. For questions of personal world-view and how that affects your subjective experience, then I doubt such a dogmatic stance is universally ideal. Anyway, I ramble.
- Veelox 9y ago
  My understanding of the Everettian interpretation is that all worlds that are possible in QM exist and we exist in one of them, the wiki article for this is called many-worlds. I may be being obtuse but this seems like a fundamentally different claim than what I normally see as claimed when talking about the multiverse. The multiverse, in my understanding, claims that there are infinitely many universes, even some that will have different QM from our universe because those universes started differently. To use a CS analogy, many-worlds says that the tree branches the maximum number of time at each nodes. Multiverse claims there are infinitely many trees. Do I have a different understanding then you when it comes to what constitutes a multiverse? > Say we take a firm stance on only wanting to keep around models that are constrained by scientific experiment. My initial asking of this question is that it appears to me that the multiverse is not constrained by scientific experiment. I have read most of the comments and your gets the closest to something predictive but even then, it is still just one interpretation of QM. The other option is that there is something in string theory that implies multiverses but as of yet string theory is just theory and from what I understand string theory doesn't require a multiverse, it requires more dimensions which might cause a multiverse. I ramble as well.

by Veelox 9y ago

xelxebar 9y ago

> I have heard no evidence-based explanation for what lower level mechanisms cause our universe that imply a multiverse. The example I have in mind is the Everettian interpretation of QM. Formally, we have a Hilbert space and decoherence. We can interpret decohered regions in the Hilbert space as separate universes. These mechanics are an artifact of the mathematical formalism. Interestingly, the Copenhagen "interpretation" would get ruled out by Occam's Razor since it adds the notion of wave collapse on top of the formalism without experiment being able to differentiate between the two. > I think instead of X + God as the explanation it should instead just be God. If that works for your needs, then more power to you. We can also jump a meta-level with Occam's Razor though. Say we take a firm stance on only wanting to keep around models that are constrained by scientific experiment. Then we need, say, the Standard Model and General Relativity, but I'm not sure the God Did It model would survive said filter. For scientific progress (i.e. the cooperative human effort of science), such a hard-nosed approach seems to have worked unreasonably well so far. For questions of personal world-view and how that affects your subjective experience, then I doubt such a dogmatic stance is universally ideal. Anyway, I ramble.

Veelox 9y ago
My understanding of the Everettian interpretation is that all worlds that are possible in QM exist and we exist in one of them, the wiki article for this is called many-worlds. I may be being obtuse but this seems like a fundamentally different claim than what I normally see as claimed when talking about the multiverse. The multiverse, in my understanding, claims that there are infinitely many universes, even some that will have different QM from our universe because those universes started differently. To use a CS analogy, many-worlds says that the tree branches the maximum number of time at each nodes. Multiverse claims there are infinitely many trees. Do I have a different understanding then you when it comes to what constitutes a multiverse? > Say we take a firm stance on only wanting to keep around models that are constrained by scientific experiment. My initial asking of this question is that it appears to me that the multiverse is not constrained by scientific experiment. I have read most of the comments and your gets the closest to something predictive but even then, it is still just one interpretation of QM. The other option is that there is something in string theory that implies multiverses but as of yet string theory is just theory and from what I understand string theory doesn't require a multiverse, it requires more dimensions which might cause a multiverse. I ramble as well.