Space and time can be emergent from the quantum formalism. We don't know that it's true in any obvious way, but it's certainly conceivable. Decoherence is a dynamical phenomenon that spreads outward alight cone within parent space time. branches of the wave function are like or higher level emersion phenomenon. They are not something that exists at the fundamental level. It's human beings who care about the class a limit. It's not the universe that cares about the classical limit.
Welcome to the May 2022 Ask Me Anything episode of Mindscape! These monthly excursions are funded by Patreon supporters (who are also the ones asking the questions). I take the large number of questions asked by Patreons, whittle them down to a more manageable size — based primarily on whether I have anything interesting to say about them, not whether the questions themselves are good — and sometimes group them together if they are about a similar topic. Enjoy!
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