All Questions
Tagged with non-locality epr-experiment
15
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EPR effect, non-locality, positivism and realism
In the framework of EPRB experiments, has an experimental verification been performed of the conservation of 2-time correlations of Bob's photons polarization despite Alice's polarization measurements?...
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4
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Could reducing entanglement by unitary operations allow for FTL-communication? (and why not?)
About the closure: This Question is about why manipulating 1 particle of an entangled pair unitarily can’t cause measurable consequences on the other and how this manifests in the concretely described ...
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6
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What was the fallacy in EPRs chain of arguments?
Let's say, there is an entangled system of two electrons with opposite spins; The joint system is in a state of eigenvectors for z-Spin ( $S_z$) with both particles far away from each other:
$$|\Psi\...
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2
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Is the possible Bell's test loophole of entangled particles communicating at a non instantaneous but FTL speed addressed and eliminated? [closed]
TLDR:
There seems to be a loophole in Bell's test that is not addressed or eliminated before we can successfully conclude that it proves that the Universe is unreal and non local. The entangled ...
1
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1
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How can we be sure Bell's theorem disproves local realism when we are not sure whether the measuring apparatus is in some form of entanglement or not? [duplicate]
Bell's therorem seems to disprove localism because measuring, let's say spin of an entangled electron, seem to communicate the measurement to it's another pair instantaneously.
But isn't another thing ...
2
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1
answer
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Measurement of the spin of the EPR pair in two orthogonal directions and how did Einstein tackle this?
Let us consider two types of measurement in the EPR experiment. In Bohm's description of this experiment, the state of the electron-positron (called the EPR pair) is given by
$$
|{\rm EPR} \rangle =\...
4
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4
answers
689
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What is wrong with violation of locality (EPR paradox)?
When studying the EPR paradox, at some point we must resign ourselves that Reality and Locality can not be both true in the current theory of quantum mechanics.
A lot has been said in Physics.SE about ...
2
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1
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Where does the negative cosine relation for quantum mechanical CHSH correlations come from?
I have been lately looking into Bell's inequality. I have noticed a recurring graph that depicts the correlation of two spins when measured at different angles, for the quantum and the classical case:
...
2
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1
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183
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The non-locality of Quantum Mechanics
I often heard physicists mentioning the EPR paradox or the quantum entanglement when talking about the non-locality of quantum mechanics, but wasn't quantum mechanics already non-local from the ...
0
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2
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EPR-Bohm paradox and Robertson uncertainty relation [closed]
Consider Bohm's version of the EPR paradox, where spin-1/2 are used.
The bipartite system is in the state
$$
\vert \Psi\rangle = \dfrac{1}{\sqrt{2}} \left( \vert \uparrow_x \rangle_A \vert \...
1
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0
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Is there any basis in stating there are different levels of 'locality' or 'reality', within physics or physical theories?
EPR’s reality criterion and quantum realism has this paragraph (the paper has 0 citations, and I'm personally happy to call this metaphysics, but still!):
A popular interpretation of Bell’s theorem ...
2
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2
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299
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How is locality preserved in quantum mechanics?
I was reading this post:
http://motls.blogspot.com/2015/06/locality-nonlocality-and-anti-quantum.html
Specifically here: "There is no nonlocality. There is no action at a distance. There is no doubt ...
9
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3
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Why would classical correlation in Bell's experiment be a linear function of angle?
Sorry if it's a newbie question, but I have trouble understanding the following part in the Wikipedia's explanation for the Bell's theorem:
With the measurements oriented at intermediate angles ...
4
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6
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Local EPR-experiments with photons in vacuum?
The principle of non-locality states "that an object is influenced directly only by its immediate surroundings." (Wikipedia)
When two entangled particles are measured in an EPR experiment, we ...
2
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1
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102
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Is it possible to determine the state or values of something without measuring it
To give context to this question, I am currently looking into non-locality / hidden variables / Bell's Theorem, EPR / etc.
I've noticed the assertion that the values / state of something when ...