All Questions
Tagged with locality bells-inequality
28
questions
7
votes
4
answers
3k
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Confusion around Bell's Theorem and Locality
I recently got interested in foundational aspects of quantum mechanics and I have some questions:
Bell's theorem proves that any local, deterministic theory with statistical independence can't account ...
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0
votes
0
answers
71
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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
0
votes
0
answers
45
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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
2
votes
4
answers
1k
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Understanding superdeterminism
I was reading about superdeterminism and it was a bit counter-intuitive. The idea of having a hidden variable on the measurement device is very rational. For example, if we emit light to a constrained ...
0
votes
1
answer
276
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Is a super-deterministic universe local or nonlocal? [closed]
Bell predicted predetermined (nonlocal) choice as the criteria for a super-deterministic universe.
...our belief that we are free to choose to do one experiment rather
than another, absolutely ...
2
votes
2
answers
914
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How does Bell's theorem disprove realism?
I am told that the the violation of Bell's inequalities prove that the universe cannot have local realism. That is to say, the universe cannot both be local and real.
I understand how Bell's theorem ...
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2
votes
3
answers
374
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Don't Bell experiments rule out local non-realism too? [duplicate]
Bell experiments rule out local realism (hidden variables). But it seems to me that it also rules out local non-realism (no hidden variables).
Local non-realism makes 2 claims;
Two distant events can'...
- 2,982
4
votes
1
answer
295
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On the Bell's Theorem / Bell-type Inequalities and the Kochen-Specker Theorem
It appears to me that the Kochen-Specker theorem, if not Gleason’s theorem already, seals the fate of realism / value definiteness (with possibly the additional assumption of non-contextuality, ...
- 173
0
votes
2
answers
483
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Why quantum mechanics doesn’t break locality in entanglement but hidden variables theories will?
What makes it so that quantum mechanics doesn’t break locality in entanglement yet hidden variable theories will?
In Bell‘s inequality said that hidden variables theories need to break locality in ...
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3
votes
0
answers
185
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Does reality express non-local realism, local non-realism or non-local non-realism? [closed]
So I read that Bell's tests prove that reality cannot follow the requirements of both realism and locality. My understanding is that:
Realism: Objects have definite properties before they are ...
-1
votes
1
answer
228
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Does Bell's theorem imply nonlocality using a false assumption? [closed]
In https://arxiv.org/abs/1409.5158, the author concludes that Bell tests cannot refute local realism, because they employ a wrong analysis. He says:
"The quantum joint prediction cannot be ...
- 1,145
10
votes
3
answers
488
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How exactly does the proof of Bell's theorem fail if you remove the locality assumption?
In this paper Bell derives his famous inequality using the assumtions of locality and realism. In order to understand how the locality assumption affects the derivation of the inequality, and why it ...
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11
votes
1
answer
672
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Where is locality used in CHSH/Bell's inequality?
A very similar question is asked here, but I'm still confused :(
From Bell, in a hidden variable model, $A = A(\lambda, a)=\pm 1$ is the observed spin of the first particle around axis $a$, and $B = ...
- 113
2
votes
1
answer
133
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Distinguish Definitions: Realism Scientific, Realism, and realistic
I was readying about study about bell's theorem, where I had the question about some definitions.
Here's some of my summaries:
Scientific Realism:
(https://en.wikipedia.org/wiki/Scientific_realism#...
- 1,048
1
vote
0
answers
152
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Relativity and Bell's inequalities
I am reading a collection of interviews taken with prominent physicists as in an aftermath of famous Alain Aspect experiment. Between them John Bell states that if local realism has to go, he would be ...
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