Suppose we fire a photon P at a polarisation filter F(adsbygoogle = window.adsbygoogle || []).push({}); _{1}, and it passes the filter, thus forcing the polarisation of P in an eigenstate M_{1}. Subsequently, the photon falls through a polarisation filter F_{2}, forcing P in eigenstate M_{2}.

Now, if I understand correctly, the probability of P passing F_{2}, thus becoming in eigenstate M_{2}when inknowneigenstate M_{1}, can be exactly determined by therelativesettings of F_{1}and F_{2}.

So, we have P passing F_{2}with a known probability. Now, In CI the probability represents the factual state of P (M_{2}or the perpendicular to M_{2}), while MWI allows for both M_{2}and perpendicular to M_{2}. So, it seems as if in MWI both eigenstates (M_{2}and the perpendicular) both have a probability of 100% of occuring, only in two different worlds. So, it seems as if MWI contradicts the probabilistic nature of QM?

What is the explanation for this?

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# CI vs MWI - contradictory?

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