Questions tagged [locality]
The locality tag has no usage guidance.
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Please tell me about "Action at a distance" in Electrodynamics [closed]
I am confused about how test charge informed about source charge. So I research on it. Web said me that it is "Action at a distance phenomenon". What is this? I am a first year Undergraduate ...
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Is Electrostatics Local?
We can solve uniquely for the electrostatic potential $\phi(x)$ of some given charge distribution if we set the boundary condition that $$\lim_{|x|\to\infty}\phi(x) = 0$$ (or whatever boundary ...
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How is information defined when considering locality in quantum mechanics?
$\newcommand{\ket}[1]{|#1\rangle}$
My question is a follow-up from this discussion about the presence of non-local correlations in a theory that is deemed local. The first answer talks about the ...
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Reality, locality, and universality in the EPR paradox
Apologies if this has been asked before. I did some searching but didn't see it anywhere asked quite like this. Thanks in advance for any insights.
Caveat: I am an organic chemist and thus ...
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Is there any restriction for locally mapping a given 2-qubit density matrix into a desired 2-qubit density matrix with lower entanglement?
Suppose we're given a 2-qubit density matrix($\rho_{4\times4}$). we can apply two local maps on each of these qubits seperatly. So the output is density matrix($\rho^{\prime}_{4\times4}$).
I'm ...
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Definition of “quasi-locality” in Wilsonian RG scheme
I’m studying about the holographic RG with this paper.
In that paper they say Wilsonian action expects quasi locality, but I’m not sure what “quasi-locality" exactly means.
If quasi-locality ...
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Why is quantum entanglement considered to be an active link between particles?
From everything I've read about quantum mechanics and quantum entanglement phenomena, it's not obvious to me why quantum entanglement is considered to be an active link. That is, it's stated every ...
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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 = ...
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Bell's theorem for dummies, how does it work?
I've been reading up on theoretical physics for a few years now and I feel like I am starting to get an understanding of particle physics, at least as much as you can from Wikipedia pages. One thing ...
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Can you model relativistic interactions without locality?
Assume $c=1$
I've been doing relativity by myself so I may be making some assumptions here that I would not have if my learning had been more extensive.
One such assumption is that you can model the ...
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Is conservation of energy a local law in Quantum field theory? [closed]
From Wikipedia,
"The local energy conservation in quantum field theory is ensured by the quantum Noether's theorem for the energy-momentum tensor operator. Thus energy is conserved by the normal ...
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Many Worlds locality and EPR experiment
I've read in Sean Carroll's book (Something Deeply Hidden) that the Many-Worlds interpretation of quantum mechanics might be the only way to avoid instantaneous effects of entanglement, by having the ...
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Lorentz invariance (LI) of time ordering operation
At Srednicki after eq. (4.10), we have a discussion about that the time ordering operation. Have to be frame inv. I.e it has to be LI.
He wrote that for timelike separation we don't have to worry ...
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On the notion of Local Causality
In 1976, John Bell proved that any locally causal theory can't account for certain observed correlations, he formulated the local causality hypotesis in terms of "local beables".
In ...
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What is a local operator in quantum mechanics?
In quantum mechanics, what exactly is meant by "local" operator?
What about a "global" or a "non-local" operator? Are these the same?
Can you also also help me understand what exactly is a local ...
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