Some questions about time and causality in the MWI

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Posy McPostface
Forgive my novice question; but, how does one explain the fact that decoherence doesn't contradict the evolution of the wavefunction in every world? Meaning, how is causality preserved in each world and what concept of time is professed wrt. to each world in the MWI? In other words, it seems like time is absolute and not relative with respect to each world in the MWI and decoherence being able to happen at all. Or am I understanding the wavefunction wrong here, as if it were multiple entities existing in each world and not one dictating the behavior of all worlds?
 
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What do you mean by "contradict the evolution of the wavefunction"?
Meaning, how is causality preserved in each world
It does't make much sense to talk about a single world if you want to look at time evolution. Anyway: The same way it is preserved in nearly all interpretations. The wave function at time T depends on the wave function at times t<T only.
Posy McPostface said:
In other words, it seems like time is absolute and not relative with respect to each world in the MWI
What would "relative with respect to each world" mean?
Posy McPostface said:
Or am I understanding the wavefunction wrong here, as if it were multiple entities existing in each world and not one dictating the behavior of all worlds?
I don't understand that question.
 
Nevermind, please disregard.

Thanks.
 
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