All Questions
Tagged with locality quantum-field-theory
68
questions
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57
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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 ...
- 61
2
votes
1
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123
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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 ...
- 51
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35
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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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22
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How does locality on space time manifold M put constraints on functions on configuration space of fields?
I am reading David Skinner's notes on AQFT. In Chapter 1 page 3, he mentioned that "purely from the point of view of functions on $C$, locality on $M$ is actually a very strong restriction", ...
- 11
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101
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Understanding this abstract Lagrangian of effective field theory
I'm learning Wilson's approach to renormalization and the Effective Field Theory. Typically, the theory is defined by a Lagrangian valid up to some scale $Λ$. I saw these two definitions for 4-...
- 1,783
2
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257
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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 ...
- 317
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3
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102
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Cluster decomposition $\stackrel{?}{=}$ Translation invariance
In Weinberg Volume 1 (section 4.4), Weinberg argues for a certain structure of the interaction Hamiltonian by demanding that it produce an $S$-matrix satisfying cluster decomposition. The proposed ...
- 169
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91
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Is causality a consequence or a constraint in physics?
I wonder if causality is a constraint that we must add to physical models (if needed), or is it a consequence of Lorentz invariance and locality (or something else). In other words, which properties ...
- 595
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140
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Local algebra of AQFT vs Bisognano Wichmann Theorem
Maybe I am misunderstanding something really stupid, but I am finding it hard to think of local algebras in terms of wedge algebras. One of the claims (see, e.g., Section 3 and 4 of this paper) is ...
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115
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How do Lieb-Robinson Bounds talk about locality without the position operator?
So we know when one goes from QM to QFT Lieb Robinson bounds become micro causality. But micro causality is a statement on the commutators assuming they are space-like, time-like or light-like. ...
- 1,389
9
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2
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372
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How are we able to use quantum field theory to study systems?
I've been trying to understand the concept of locality in QFT, and I was reading this paper by Edward Witten, where he explains (on pg 13) that the state space cannot be factored into a tensor product ...
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4
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457
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How does string theory get around the argument in Weinberg's QFT?
In Weinberg's The Quantum Theory of Fields Vol. 1, an argument is presented that the three postulates of
Lorentz invariance
quantum mechanics
cluster decomposition principle
leads to quantum field ...
- 857
2
votes
2
answers
502
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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
...
- 1,742
1
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1
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298
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Is QFT "more" non-local than QM, at least mathematically?
Could physics still be local? Here's what I mean:
The Schrodinger/Dirac equations allow for quantum entanglement, right? So in that sense they are non-local physically. But they are mathematically ...
- 2,475
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366
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Are infinitesimal dilatation transformations local?
In quantum field theories, a local transformation of a scalar field $\phi(x)$ is a transformation that involves the field and its derivatives at same point. See for instance Weinberg's QFT textbok, ...
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