Questions tagged [lattice-gauge-theory]
The study of (particle physics) gauge theories on a spacetime that has been discretized into a lattice.
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References on finite temperature lattice gauge theories (LGT)
I'm struggling to understand the link between periodicity in the time direction and finite temperature when realizing gauge theories on lattice, but it seems impossible to find lectures that address ...
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What is the QCD potential for the baryon? [closed]
For the meson it is
$$V_{QCD}= -\frac 43 \frac{\alpha_s}r + kr$$
What is it for the baryon (3 quarks)? Thank you.
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2answers
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Is the QCD potential really monotonic ? How does it prevent two quarks from meson to annihilate?
The QCD potential is made of two terms
-(4/3) * alpha_s / r
that describes the short distance
and
the term
+k*r
that describes the long distance
Of course, alpha is a function of energy, so it is ...
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1answer
43 views
Spectrum of the momentum operator for free Dirac fermions on a lattice
I am studying lattice field theory and would like to understand the momentum operator for free Dirac fermions on a square lattice.
In this case one needs to discretize the momentum operator (which ...
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1answer
49 views
What's the relation between Euclidean and Minkowski entities in lattice field theory?
To my understanding, lattice QFT basically continues the time $t$ (and fields depend on it) in Minkowski space action to imaginary time $\tau\equiv it$. But normally when we do calculations in lattice ...
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How Is Are Parton Distribution Functions (PDFs) Determined In Practice And In Theory?
I have put my actual questions in bold normal font, and the rest of this question clarifies what I mean to be asking, especially in terms of the depth and kinds of information I am looking for. ...
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1answer
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What is the physical significance of links between sub lattices in the staggered fermion formulation of lattice gauge theories?
I am currently learning about Lattice Gauge theories and have come across the Lattice formulation in terms of staggered fermions (see e.g. Susskind 1977, Kogut & Susskind 1975).
As I understand ...
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0answers
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How to find propagator for domain wall fermions
I am working on domain wall fermions right now and I am trying to understand how Luescher finds the propagator for the domain wall fermions in this review https://arxiv.org/abs/hep-th/0102028 on pages ...
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1answer
78 views
Lattice gauge theory under a Lorentz transformation
Taking a grid of 'evenly-spaced' space-time points. e.g. at integer values of (x,y,z,t). Now do a Lorentz boost on this grid. We end up with a grid of points which are much closer together.
It is ...
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1answer
86 views
What goes wrong with GR as a lattice gauge theory?
If one tried to formulate General Realativity in a similar manner to say lattice QCD, what goes wrong that makes it not work?
My first thoughts are that for any particular grid, we might have a ...
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1answer
50 views
How does Pauli exclusion principle work with lattice QCD?
Say your space-time lattice has 30 fermions on the vertices. (Would they have to form a path?)
Swapping any two fermions (on the same row??) should make the amplitude of the lattice state negative.
...
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What's wrong with lattice quantum gravity?
Assume one can write the metric field on a lattice, so on each lattice point one has a value of $g^{\mu\nu}$. Similar to the way lattice QCD is formulated. Then later taking the distance between ...
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1answer
122 views
Are any quantum field theories mathematically convergent?
I know for example that theories like QED and QCD when expended perturbatively in terms of Feynman diagrams produce asymptotic series that don't converge after a large number of terms and in fact ...
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1answer
219 views
Why is lattice QCD called non-perturbative?
Like, if you are approximating a smooth structure with a discrete lattice, isn't this like a perturbation from smooth space-time?
If Feynman diagrams are a perturbative method, why are Feynamn ...
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1answer
47 views
Why is Lattice QCD done in Euclidian 4-space?
This could be a really naive question (and honestly I just don't want to dig through ArXiV review papers on lattice QCD), but my question is simple:
Why exactly is Lattice QCD done in $\mathbb{R}^4$ ...
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1answer
129 views
Temperature-dependence of quark potential in Abelian lattice gauge theory
I am working with Kapusta's "Finite-Temperature Field Theory" textbook, and am working through the first part of chapter 10. When building the correlator of the two quarks a distance $R$ apart in the ...
