For (1) the multiverse needs to be immensely larger than our universe, by a factor of at least 10106 or so “instances”. The exact double exponent depends upon how closely people have to match before it’s reasonable to consider them to be essentially the same person. Perhaps on the order of millions of data points is enough, maybe more are needed. Evidence for MWI is nowhere near strong enough to justify this level of granularity in the state space and it doesn’t generalize well to space-time quantization so this probably isn’t enough.
Why? Even without unphysically ordering arbitrary point-states, isn’t the whole splitting behavior creates at least all subjectively-distinguishable instances?
I’m not saying that it’s impossible, just that we have no evidence of this degree of multiplicity. Even if the MWI interpretation was correct, the underlying state space could be very much coarser than this thought experiment requires without any effect on experimental observations at all. Or something even weirder! Quantum theories are an approximation, and pushing an approximation to extremes usually gives nonsense.
Saying that there are literally uncountably infinite many real states is going far beyond the actual evidence. We don’t—and can’t—have any evidence of actual infinity or indeed any physically existing entities of number anything like 10^million.
Unfortunately the nature of reality belongs to the collection of topics that we can’t expect the scientific method alone to guide us on. But perhaps you agree with that, since in your second paragraph you essentially point out that practically all of mathematics belongs to the same collection.
Why? Even without unphysically ordering arbitrary point-states, isn’t the whole splitting behavior creates at least all subjectively-distinguishable instances?
I’m not saying that it’s impossible, just that we have no evidence of this degree of multiplicity. Even if the MWI interpretation was correct, the underlying state space could be very much coarser than this thought experiment requires without any effect on experimental observations at all. Or something even weirder! Quantum theories are an approximation, and pushing an approximation to extremes usually gives nonsense.
Saying that there are literally uncountably infinite many real states is going far beyond the actual evidence. We don’t—and can’t—have any evidence of actual infinity or indeed any physically existing entities of number anything like 10^million.
Unfortunately the nature of reality belongs to the collection of topics that we can’t expect the scientific method alone to guide us on. But perhaps you agree with that, since in your second paragraph you essentially point out that practically all of mathematics belongs to the same collection.