All Questions
7
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What do we mean by causality when we say that entanglement measurements are uncaused? [duplicate]
I’m having a hard time wrapping my head around how the measurement of particle A does not affect the state of an entangled particle B even if no superluminal speeds exist.
Suppose Alice makes a ...
user385269
6
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3
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Bell's inequality for angles 120°
In 1964, John Bell first derived the original Bell inequality, $|E(a,b)-E(a,c)|\leq1+E(b,c)$. Here $a,b,c$ are three different possible spin measurement directions, and $E$ is the measured ...
4
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1
answer
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How can a basis change make a state suddenly separable?
I am working through my quantum optics textbook by Grynberg, Aspect and Fabre, and this concept has tripped me up a little.
(13) is an inseparable state, whereas (15) IS separable - but they are the ...
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14
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2
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Implications of MIP*=RE for physics?
Background
Earlier this month (Jan 2020) a pre-print was posted to the arXiv claiming to have proved the equivalence of the complexity classes $\mathrm{MIP}^{*}$ and $\mathrm{RE}$ (see below for ...
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Could the definition of the experiment result occur before measurement?
Is there any fundamental demonstration that result of an experiment cannot have been determined before the measurement, yet according to the probabilistic rules of quantum mechanics?
I understand ...
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23
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How do we know that entanglement allows measurement to instantly change the other particle's state? [duplicate]
I have never found experimental evidence that measuring one entangled particle causes the state of the other entangled particle to change, rather than just being revealed.
Using the spin up spin down ...
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2
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What happens if we measure the two entangled systems of the Bell test simultaneously?
Consider the Bell state $|\psi\rangle =\frac{|00\rangle +|11\rangle}{\sqrt{2}}$.
When measuring one of the individual systems, the superposition is projected onto one of the eigenstates $|00\rangle$ ...
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