Copenhagen:
You bounce a photon off a half-silvered mirror and don't look at the results: no universe split.
You bounce a photon off a half-silvered mirror and look at the results: Bam! Split universe.
MWI:
You bounce a photon off a half-silvered mirror and don't look at the results. Since the physical state of your brain is not causally dependent on the destination of the photon, you don't branch into two mwenglers in any noticeable way.
You bounce a photon off a half-silvered mirror and look at the results. Since you've made the state of your brain causally dependent on an event with quantum randomness, you branch into two mwenglers which are different on a macroscopic level. Two persons, which happen to share a causal history up to looking at the experimental outcome.
Copenhagen:
... You bounce a photon off a half-silvered mirror and look at the results: Bam! Split universe.
Copenhagen Interpretation never splits universes. Instead, you have a wave function collapse in the one and only universe.
You bounce a photon off a half-silvered mirror and don't look at the results. Since the physical state of your brain is not causally dependent on the destination of the photon, you don't branch into two mwenglers in any noticeable way.
In MWI, you NEVER branch in to two anythings in a "noticeable" way. All the m...
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