All Questions
Tagged with non-locality bells-inequality
59
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Bohmian mechanics, Leggett inequality, realism and nonlocality
Very often it is said that the Bell inequality has ruled out the possibility of hidden variables (HV) in QM. This is incorrect since Bell inequality has ruled out local hidden variables: nonlocal HV ...
- 283
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4
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All the logically possible ways to get around Bell-type inequalities
I'm a high school student, so my (mis)understanding here is not very rigorous or precise, but I will write it below so as to concretely frame my question:
Bell's theorem takes three assumptions ...
- 248
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Do Bell’s inequalities assume determinism?
I was watching a video of Tim Maudlin where he talks about how the CHSH version of Bell’s inequalities do not assume determinism and only assume locality. He said that it is a common misconception ...
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Does local realism imply entangled photons are equal (or opposite)?
I'm watching a video about Bell's inequality and how there can be no local hidden variables. They explain it using photons and whether they pass through a polarizer or not when they're oriented at ...
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Can a point in the quantum set of correlations violate more than one independent facet Bell inequality?
Usually, depictions of the quantum set of correlations and the local polytope look something like:
In this image it looks like non-local points belonging to the quantum set (in yellow) violate only ...
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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 ...
- 107
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1
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235
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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 ...
- 107
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Why does it make sense to add/subtract the results of measuring in 2 different bases in Bell's inequality when each observer only measures 1 property?
In the CHSH inequality, we construct an experiment whereby two observers each receive a particle and measure two given properties of their particles, for which the outcomes are ±1. We then consider ...
- 103
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Have spin-correlation experiments been done on entangled particles other than photons?
I know that Bell experiments on spin correlations have been done with entangled photons, but have spin-correlation experiments ever been done on entangled particles other than photons?
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Is degeneracy of eigenvalues required for the Kochen-Specker theorem?
I'm wondering why the operators for the Kochen-Specker theorem are 3-dimensional while they only produce two eigenvalues $\{0,1\}$. Is this degeneracy always needed regardless of the dimensionality of ...
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In the Bell CHSH experiment, why are Alice and Bob not allowed to pre-arrage their measurements?
From Nielsen and Chuang, Chapter 2:
Imagine we perform the following experiment, illustrated in Figure 2.4. Charlie prepares
two particles. It doesn’t matter how he prepares the particles, just that ...
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Quantum mechanics: does many-worlds interpretation remove nonlocality? Bell-type experiment
Trying to make sense of many-worlds interpretation and see if it removes nonlocality or solves other problems. It appears to me that branching is equivalent to collapse... so trying to see what I'm ...
- 1,224
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How are the different derivations of Bell's inequality related?
I wanted to ask about two different derivations for bell's inequality for the known CHSH inequality.
One derivation is the one bell originally used in 1971
this derivation is thoroughly written in ...
- 21
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Non-locality and Twistor functions
Is there a nice intuitive way to visualize the concept of non-locality associated to twistor functions? And how is it related to the type of non-locality we encounter in Quantum Mechanics?
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Has there been experimental evidence that entangled state collapses simultaneously?
If we observe the observable of one particle among two particles which are entangled each other and separated far away, we can determine the value of the other particle’s same observable from the ...
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