The true point of no return has to be indeed much later than we believe it to be now.
Who is "we", and what do "we" believe about the point of no return? Surely you're not talking about ordinary doctors pronouncing medical death, because that's just irrelevant (pronouncements of medical death are assertions about what current medicine can repair, not about information-theoretic death). But I don't know what other consensus you could be referring to.
Surely I do. The hypothesis that after a certain period of hypoxia under the normal body temperature the brain sustains enough damage so that it cannot be recovered even if you manage to get the heart and other internal organs working is rather arbitrary, but it's backed up by a lot of data. The hypothesis that with the machinery for direct manipulation of molecules, which doesn't contradict our current understanding of physics, we could fix a lot beyond the self-recovery capabilities of the brain is perfectly sensible, but it's just a hypothesis without t...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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