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 cal

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.