All Questions
Tagged with quantum-chromodynamics lattice-model
27
questions
7
votes
1
answer
206
views
What makes lattice QCD computationally tractable?
I don't know anything about lattice QCD. Therefore, at first glance it seems to me that lattice QCD should be computationally intractable for all practical purposes.
Let's assume that we only care ...
- 6,591
0
votes
1
answer
118
views
How to write a naive Dirac matrix for Lattice QCD?
I'm trying to write down the naive Dirac matrix (with fermion doubling) for a LQCD simulation with one quark, for now. I initialized the $SU(3)$ gauge field and the quark field. The quak field has 4 ...
- 31
4
votes
1
answer
264
views
Real time lattice simulation
A typical simulation of lattice quantum chromodynamics uses imaginary time, so the weight function of the path integral is positive definite $e^{-S_E}$.
In the case of metropolis-hastings, the ...
- 377
0
votes
1
answer
115
views
What are some good resources to learn about perturbative and non-perturbative approaches to QCD, for example Lattice QCD, at an introductory level?
I am writing at an introductory level about the anomalous magnetic moment of the muon and part of that is the subsequent Lattice QCD that potentially verifies the results from the experiments that ...
6
votes
1
answer
483
views
Lattice spacing in lattice QCD
It is known that the lattice spacing in lattice QCD is not an external parameter and needs to be calculated, also the lattice beta parameter scales the lattice spacing ($a$) and goes as a function of ...
- 377
3
votes
1
answer
1k
views
Recommend books for learning lattice QCD
I want to learn lattice QCD by myself, but I don't know how to start. Can you recommend some books for lattice QCD?
2
votes
1
answer
75
views
Are gravitons equivalent to extra localised lattice points?
So imagine space is a regular square mesh or lattice. In a theory like QCD, the photon lines are placed along the edges of this graph to form paths.
The space is supposed to represent simple ...
user84158
1
vote
0
answers
58
views
Is is cheating to use alpha strong (instead of V_QCD) to argue that there is asymptotic freedom of QCD?
For asymptotic freedom of QCD, people give the argument that alpha_strong decreases at high energy (thus there is freedom at low distance).
But if we make the reasoning on the QCD potential, for ...
1
vote
2
answers
458
views
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 ...
5
votes
1
answer
168
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 ...
- 2,665
2
votes
0
answers
126
views
Questions on how Wilson loops relate to field & charge conservation, and lattice QFT
The path-ordered exponential from which the Wilson loop is traced is, crudely,
$$ \prod (I+ A_\alpha dx^\alpha) = \mathcal{P}\,\mathrm{exp}(i \oint A_\alpha dx^\alpha )$$
which returns a matrix $\...
- 970
3
votes
1
answer
171
views
What is the effect of including additional representations in the action of a lattice gauge theory?
I'm reading Introduction to Quantum Fields on a Lattice by Jan Smit. When introducing the lattice gauge-field action as a sum over plaquettes, Smit says that in general the action should include a sum ...
- 223
0
votes
1
answer
676
views
Computation of String Tension in Lattice QCD
There is a quantity called String Tension in lattice QCD calculation.
How is this quantity (String Tension) defined and computed in Lattice QCD? Are there some useful formulas to define it both in ...
- 4,336
0
votes
0
answers
85
views
Instanton effects on condensates: (pseudo)scalars, (pseudo)vectors, tensor
I have heard that the instanton effect in quark matter causes the di-quark condensate to be Lorentz scalar. As opposed to the Lorentz scalar, there are possibilities that the condensates are Lorentz ...
- 4,336
5
votes
1
answer
541
views
Is quark and gluon orbital angular momentum predicted to have the rest of the proton's spin?
The Phys.org news item How did the proton get its spin? outlines various experiments that probe proton structure and are sensitive to spin, and the current news is that CEBAF's major energy upgrade ...
- 6,263