Questions tagged [non-locality]
The non-locality tag has no usage guidance.
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Does a measurement violate conservation law? [duplicate]
(Edited according to the discussion with @naturallyInconsistent. The edited part is highlighted in italic.)
We have an experimental bench and we assign a coordinate system $(x,y)$ to it.
We shall call ...
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Does a nonlocal deterministic hidden variable theory imply retrocausality?
I've had this idea for a while, and recently I stumbled upon a short paper from N. Gisin that formulated this idea, but I could not find a meaningful discussion on the problem. The paper that I found ...
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What's mechanism of "spooky action at the distance"? [duplicate]
Nobel prize 2022, a local theories of hidden variables are ruled out, Einstein's "spooky action at a distance" seems to be a reality.
Is there ANY explanations of this behavior of quantum ...
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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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How can two phonons be entangled when the atoms in the crystal are not?
It is my understanding that you can use phonons to make a gaussian packet, which would behave like a quantum particle. I also believe that you can make two such packets and entangle them, that is ...
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What is the difference between nonlocality and entanglement?
I'm a bit confused about the difference and relation between (quantum) nonlocality and entanglement.
To give some context about my confusion, I was reading this paper: Brunner, Nicolas, et al. "...
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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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How is the non-locality of a theory apparent from its mathematical form?
I am reading Relativistic Quantum Mechanics by Bjorken and Drell and on page 5 they present the following attempt at a relativistic Hamiltonian for a free particle
\begin{equation}
i\hbar\frac{\...
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Local fields in relativity with pure creation operators
The Wikipedia page on the Spin-Statistics theorem states that
In relativity, there are no local fields that are pure creation operators or annihilation operators.
In this answer at SE Phys, in a ...
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Are spinors intrinsically nonlocal?
I would prefer a purely classical answer since I don't think quantum mechanics (quantum field theory etc.) are necessary to answer this question and such answers will likely complicate matters. If you ...
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Nonlocality of a bug on movie screen
I am currently learning quantum mechanics using Griffiths. In the appendix, he goes to talk about EPR and Bell's inequality, and that experimental verification of Bell's inequality rejects the "...
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How localized are photons in a quantum field?
Are photons or other quanta at least somewhat localized in a quantum field?
My limited understanding of quantum field theory is that photons or other fundamental particles (quanta) are excitations 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 ...
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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 ...
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