JR; No, I can't. I am by no means knowledgeable in the field of theoretical physics, only an awe-struck and fascinated observer. I just spent an hour trying to find an answer to your question. Some physicists seem to believe that the classic "two-slit" experiment is sufficient proof; others don't. It looks as if the best argument for the multiverse interpretation is that, incomprhensible as it is, it is less incomprehensible than alternate explanation of the strange world of quantum mechanics. The best statement of this that I could find is from Max Tegmark, quoted in Wikipedia; (part of a much longer article)
"A common feature of all four multiverse levels is that the simplest and arguably most elegant theory involves parallel universes by default. To deny the existence of those universes, one needs to complicate the theory by adding experimentally unsupported processes and
ad hoc postulates:
finite space,
wave function collapse and ontological asymmetry. Our judgment therefore comes down to which we find more wasteful and inelegant: many worlds or many words. Perhaps we will gradually get used to the weird ways of our cosmos and find its strangeness to be part of its charm."
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