Questions tagged [non-locality]
The non-locality tag has no usage guidance.
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Why is quantum non-locality so surprising when quantum mechanics is a non-relativistic theory to begin with?
Ignore the fact that Quantum Field Theory (QFT) is compatible with Special Relativity (SR) for a second. Imagine we are back in a time before the construction of QFT. If Quantum Mechanics (QM) is the ...
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Is there any way to write a non-local operator nicely?
Consider the boundary(the real axis) of the 2d CFT or the D-brane. They were non local object but with well known description.
Consider the following expression,
$$\langle 0| \phi_1(z_1) \phi_2(z_2)|B\...
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Measurement of the spin of the EPR pair in two orthogonal directions and how did Einstein tackle this?
Let us consider two types of measurement in the EPR experiment. In Bohm's description of this experiment, the state of the electron-positron (called the EPR pair) is given by
$$
|{\rm EPR} \rangle =\...
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Nonlocal Gravitational energy: How to localize nontrivial topology in GR?
Ok, This question has been beaten to death. I just wanted to look at it from a slightly different angle: Einstein, Rosen, and later Wheeler considered the possibility of particles as spacetime ...
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Non-local Euler-Lagrange equations and Noether theorems
Following up my Noether theorem issues: how can Euler-Lagrange and Noether theorems be formulated for non-local lagrangians?
Two examples from the literature:
Example 1. Let $L(\phi, F(\phi))=-\dfrac{...
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Is there something that violates "time locality"?
The way I understand locality is that for an object to influence another object away from it, it has to do so through the space that separates them. It can shoot out an EM wave to the other object, ...
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Local nature of physical laws
All the laws in physics are local in nature and that's why their formulation follows differential equations. My doubt is whether the locality is a proven theorem or it is a postulate?
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Effective action as a generating functional and its derivative expansion
On page 381 of Peskin and Schroeder, equation (11.90) reads
$$ \frac{\delta^2 \Gamma}{\delta \phi_{cl}(x)\delta \phi_{cl}(y)} = iD^{-1}(x,y).\tag{11.90}$$
I am having a bit of trouble interpreting ...
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Locality of interactions and their high energy behavior
In a classic Georgi review of EFT, I have read the following quote
The result of eliminating heavy particles is inevitably a
nonrenormalizable theory, in which the nontrivial effects of the heavy
...
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Lagrangian depending on running integral
In the theory of calculus of variations, the Lagrangian generally depends on the unknown function and its first derivative. This assumption leads to the Euler-Lagrange equations.
However, I found that ...
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Interpretations for Interaction-free measurements
So I read several papers on IFM by Vaidman, Dicke, and many others, In all of them I think the Pilot wave theory is able to adequately justify the observations, but then I came across several papers ...
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Could Planck scale wormholes be a solution for non-locality?
When two entangled particles are separated, an observation made on one particle seems to be able to act at a distance to determine the state of the other particle. Is it possible, or has anyone in ...
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Non-local connection Between $D$ and $E$ (Kramers-Kronig relations)
I'm trying to solve next exercise from Jackson's Electrodynamics, Chapter 7, page 348, 3th edition:
Consider the non-local (in time) connection between $D$ and $E$,
$$\vec{D}(\vec{x},t)=\epsilon_0 \...
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Is nonlocality consistent with scale invariance?
For sure I'm excluding gravity at first step, the question is that if nonlocality is compatible with scale invariance. At the classical and quantum levels for field theory in Minkowski spacetime.
Then ...
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Why is Pilot Wave Theory nonlocal?
I have read that the Pilot Wave Theory is nonlocal and can therefore be excluded.
Why is the PW Theory nonlocal?
Isn't QM also nonlocal, as we can see it from entanglement?
I already googled the ...
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