All Questions
Tagged with quantum-chromodynamics non-perturbative
30
questions
1
vote
0
answers
40
views
Why is it justified to focus on gauge transformations constant at spatial infinity in QCD instantons?
In the context of Yang-Mills theories and QCD instantons, much of the literature and conventional treatment hinges on the consideration of gauge transformations that remain constant at spatial ...
- 841
2
votes
1
answer
257
views
Why does non-perturbative QCD need to be regularized and renormalized?
The $n$-point correlation functions of QCD, which define the theory, are computed by performing functional derivatives on $Z_{QCD}[J]$, the generating functional of QCD,
$$\frac{\delta^nZ_{QCD}[J]}{\...
- 207k
4
votes
1
answer
215
views
How does AdS/CFT help us understand non-perturbative aspects of QCD?
I've heard AdS/CFT has found applications in many areas of physics where nonperturbative aspects leave us crippled in making any simple calculations.
Among these applications, I also have heard that ...
- 8,815
2
votes
1
answer
183
views
Non-perturbative approach to high-energy physics
I know that main numerical approach to modeling high-energy physics events are Monte-Carlo event generators. But they are using perturbative description of collision and decay processes of particles.
...
- 343
3
votes
0
answers
268
views
Why is the chiral condensate a negative quantity?
The chiral condensate serves as an order parameter for the chiral phase transition. Thus, it is a finite quantity in one phase and vanishes in the other phase. It is given as a vacuum expectation ...
- 457
1
vote
0
answers
88
views
Is QCD parity conserving also non-perturbatively?
Since QCD is fundamentally non-perturbative at low energies one may ask if QCD is still Parity conserving. In the path-integral formalism using the Faddeev–Popov ghosts as gauge fixing terms the ...
- 207k
4
votes
2
answers
389
views
Reference request for non-perturbative QCD
I am looking for some good books or lecture notes that discuss non-perturbative aspects of QCD such as: chiral symmetry and chiral symmetry breaking; the QCD phase transition and the QCD phase diagram;...
- 457
0
votes
1
answer
116
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 ...
- 543
0
votes
0
answers
55
views
Physical interpretation of hadron distribution amplitudes
A parton fragmentation function can be interpreted as the probability that a final state hadron originated from that particular hadron.
A parton distribution function can be interpreted as the ...
- 391
2
votes
0
answers
44
views
$SU(2)$ gauge SUSY with Affleck-Dine-Seiberg term
Consider SUSY gauge theory with $SU(2)$ group and matter fields $Q$ and $\bar{Q}$ in fundamental and anti-fundamental representations correspondently and the following superpotential:
$$W=\frac{{\...
- 93
2
votes
1
answer
240
views
Topological susceptibility in QCD and corresponding pole
The topological susceptibility in QCD (here I've used path integral approach, and hence I will neglect all contact terms) is defined as
$$
\kappa (p) \equiv \lim_{y \to 0}\int d^{4}x e^{ip(x-y)}Q(x)Q(...
- 4,448
5
votes
3
answers
740
views
How is $\Lambda_{\textrm{QCD}}$ relevant in the non-perturbative regime?
The famous $\Lambda_{\textrm{QCD}}$ parameter enters through the one-loop running of the QCD coupling, through a relation similar to the following:
$$\alpha_S(Q^2)=\frac{\alpha_S(Q^2_0)}{1+b\ln(Q^2/Q^...
- 18.8k
2
votes
0
answers
167
views
QCD generating functional and QCD vacuum from nonperturbative to perturbative regime!
The complete generating functional in QCD (starting from the most general renormalizable, Lorentz invariant and gauge invariant Lagrangian) given by $$Z_\theta[J]=\int \mathcal{D}A \exp i\int d^4x~ {\...
- 26.8k
8
votes
2
answers
2k
views
What's the difference between perturbative QCD, non-perturbative QCD, and gauge theory QCD?
I'm trying to get the ideal of QCD, and it turns out that there seems to be several versions, and some of which does not appear to agree with each other at a glance.
What's the difference, and how ...
CommunityBot
- 1
7
votes
1
answer
2k
views
Why is the temporal gauge $A_0=0$ so popular in discussions of non-perturbative effects?
Almost every discussion of non-perturbative effects in Yang-Mills theory mentions in passing that they work in the temporal gauge. Why is this the case?
A good example is the QCD vacuum. Almost ...
- 25k