The bells-inequality tag has no wiki summary.
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Why Quantum correlation is not uniform in this diagram?
Following diagram is from a Wikipedia article which shows Quantum Correlation for local hidden variables and Quantum Mechanics and experiments confirm Quantum Mechanics predictions.
My question is ...
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How do we know that there isn't a classical solution to the measurement problem/Quantum Mechanical uncertainty?
It was mentioned to me that it can be shown that there is no classical explanation for the uncertainty in Quantum Mechanics -- i.e. that there are no hidden workings that we have just not yet seen, ...
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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 ...
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Bell's Theorem graph
My friends and I got into an argument about determinism, and I brought up that quantum events are random. But I couldn't prove it.
I found the Wikipedia page on Bell's theorem, which seems to imply ...
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Tracking down the locality assumption in a CHSH inequality derivation
CHSH inequality requires both locality and realism. I will equate here realism with counterfactual definiteness.
Now counterfactual definiteness tells us that given two different measurements on the ...
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EPR vs. EPRBB? Why can't we perform the original EPR experiment?
The EPR gedanken experiment was invented by Einstein Podolsky and Rosen in 1935.
It involved positions and momenta. In 1957, Bohm revised this gedanken experiment into one involving spins, or ...
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Is Stephen Wolfram's NKS, an attempt to explain the universe with cellular automata, in conflict with Bell's Theorem?
Stephen Wolfram's A New Kind of Science (NKS) hit the bookstores in 2002 with maximum hype.
His thesis is that the laws of physics can be generated by various cellular automata--simple programs ...
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What are the “loopholes” in past Bell's theorem experiments?
I am intrigued by the following Phys.org article:
Researchers began using photons in 1980s to test Bell's theory and determine if Einstein's reasoning is right or wrong. Since then, researchers ...
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How do we show that no hidden variable theories can replace QM?
I've always hit two big stumbling blocks in conceiving of the proof or disproof of hidden variable theories as being even valid idea, let alone an answerable question... I feel I must be ...
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What combinations of realism, non-locality, and contextuality are ruled out in quantum theory?
Bell's inequality theorem, along with experimental evidence, shows that we cannot have both realism and locality. While I don't fully understand it, Leggett's inequality takes this a step further and ...
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How does Bell's theorem rule out the possibility of local hidden variables?
It seems to be common consensus that the world is non-deterministic and this is proved by Bell's theorem.
But even though Bell's experiments proved that the theory of quantum mechanics work, How does ...
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States diagonal in the tensor product of Bell states.
Bell-diagonal states are 2-qubit states that are diagonal in the Bell basis. Since those states lie in $\mathbb{C}^{2} \otimes \mathbb{C}^{2}$, the Peres-Horodecki criterion is a sufficient condition ...
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Assumptions in Bell's Theorem
It is often Stated that Bell's Theorem is equivalent to the statement: No theory of Local Hidden Variables can reproduce all of the predictions of quantum mechanics. I see nowhere in Bell's Theorem ...
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Does this Bell's experiment actually disprove LHVT
I'm watching some archived video lectures on QM in Coursera given by Umesh Vazirani from UC Berkeley and I have a question regarding a Bell's experiment (I guess something close to this) described in ...
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Generalizations of Bell's inequality to quantum field theory
Can anyone refer me to some sources on generalizations of Bell's inequalities to quantum field theory (as opposed to quantum mechanics)? Scalar fields would be enough.
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Photon source for Bell test
Wiki tells us that In practice most actual experiments have used light, assumed to be emitted in the form of particle-like photons (produced by atomic cascade or spontaneous parametric down ...
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Interpretation of “superqubits”
Two very intriguing papers recently appeared on the arXiv, claiming that one can use "superqubits" -- a supersymmetric generalization of qubits -- to violate the Bell inequality by more than standard ...
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Can cellular automata be reconcilied with quantum mechanics?
CAs are deterministic representations of the universe, which, according to the Bell's inequality are not entirely accurate. Cells interact "locally" (only with the closest neighbours), while quantum ...
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Why does quantum mechanics invalidate one of locality and realism?
I am approaching this from an intuitive perspective and I don't speak the language. However, I have been doing a lot of reading about Bell's Theorum and how invalidates either locality or ...
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On Bell's Inequality (Classical Intuition) and Quantum Mechanical Counter Intuition
This posting is directly related to the issue in The System and the Measuring Gadget.
The QM expectation is given by:
$$\langle\sigma_{1}.\vec{a}{\;}\sigma_{2}.\vec b\rangle=-\vec a.\vec b$$
In the ...
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Would Einstein have accepted the presumptions that lead to the Bell inequality?
To check the correlation between Hidden Variable Theory and Quantum Mechanics, Bell calculated the expectation value
$<\sigma_{e}(\vec a,\vec V) \sigma_{p}(\vec b,\vec V)> = \int d^n V ...
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Show quantum entanglement to a classical thinker
Can someone describe a simple experiment to convince a person thinking about physics classically (called Claus) that quantum mechanics has something weird, entangled?
I mean an experiment that he ...
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What exactly does $S$ represent in the CHSH inequality $-2\leq S\leq 2$?
What exactly does $S$ represent in the CHSH inequality
$$-2~~\leq ~S~\leq ~2?$$
Sorry I've been reading for a couple days and I can't figure out what exactly $S$ is and the math is a bit over my ...
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What characterizations are available for two-photon Bell state light sources?
It is often technologically important to know how photon statistics change over time when a light source is turned on. A light source that comes to full intensity/visibility in a nanosecond after it ...
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Disproof of Bell’s Theorem
The half-page arxiv doc by Joy Christian of Oxford Uni, UK has the Title and Abstract:
Disproof of Bell’s Theorem
We illustrate an explicit
counterexample to Bell’s theorem by
constructing a ...
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Bell's theorem and why nonlocality is problematic
I generally hear it assumed that Bell's inequality implies violation of counterfactual definiteness, because locality is considered sacrosanct. I understand of course that measurable violations of ...
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How can we be sure that nature isn't “faking” quantum statistics?
In a recent publication, Experimentally Faking the Violation of Bell’s Inequalities (Gerhardt 2011) (arXiv version), the statistics of quantum mechanics is faked using classical light sources.
But if ...
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Do Bell inequality violations appear instantly when the source is turned on, or do they increase over time?
This experimental Question is a result of reading a particular article on Bell violations. I addressed the e-mail below to the corresponding authors —because who knows, they might reply— but it is not ...
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Bell polytopes with nontrivial symmetries
Take $N$ parties, each of which receives an input $s_i \in {1, \dots, m_i}$ and produces an output $r_i \in {1, \dots, v_i}$, possibly in a nondeterministic manner. We are interested in joint ...
