if multiple worlds really are "splitting"
What if instead of talking about "many worlds" we just said "no collapse"? If there's just this state and it evolves according to Schroedinger's equation. Then then of course there's conservation of energy.
Sure, I'm certainly not saying that the Copenhagen interpretation is correct, and my understanding is that a decoherence view is both more useful and simpler. MWI (at least as I understand it) is a significantly stronger claim. When we take the probabilities that come from wave state amplitudes as observed frequencies among actually existing "worlds" then we are claiming that there are many different versions of me that actually exist. It's this last part that I find a bit of a stretch.
Eliezer Yudkowsky and Scott Aaronson - Percontations: Artificial Intelligence and Quantum Mechanics
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