All Questions
9
questions
3
votes
1
answer
66
views
How is the mass distributed in ordinary matter?
How is the mass distributed in ordinary matter?
In the ordinary things around us, we know that most of the mass is in the cores of the atoms, the electrons around it contributing only a very small ...
- 4,912
1
vote
0
answers
137
views
Has the mass of a proton been calculated from current quarks, through the renormalization process?
That's basically my question. Has the mass of the proton been calculated using QCD and the interactions between the current quarks? Perturbative methods obviously can't be used as they deal with ...
- 450
1
vote
1
answer
109
views
Quark mass dependence of Glueball masses
In pure QCD, we have glueballs. Pure QCD can also be thought of as QCD where the fermion masses have been sent to infinity. If we vary the fermion masses (say, for simplicity, we deal with a single ...
- 6,896
5
votes
2
answers
300
views
Theta-dependence of QCD quark condensate for $m=0$
I'm trying to understand the $\theta$-dependence of the following expression for the quark condensate in QCD,
$$ \langle \bar{\psi}\psi\rangle = - \Sigma \cos(\theta)$$
taken from Eqs. (5) and (7) ...
- 1,783
5
votes
0
answers
180
views
Instantons, renormalization, and the Schwinger Model
Instantons in QCD contribute to the up, down, and strange quark masses (see, e.g., Georgi and McArthur (1981) or Kaplan and Manohar (1986)). Some papers claim that this contribution is equivalent to ...
- 1,783
2
votes
1
answer
234
views
Quark condensate alignment with Yukawa Higgs couplings
It is well known in QCD that the light quark condensates are a unit matrix in flavor space:
$\langle \bar{u}u\rangle=\langle \bar{d}d\rangle=\langle \bar{s}s\rangle\sim\Lambda_{\rm QCD}^3$.
Thus, we ...
- 1,783
7
votes
2
answers
530
views
Why doesn't the four-gluon vertex give mass to gluons?
We have a four-gluon vertex and a gluon vacuum condensate. Why doesn't this provide us with gluon masses, as in the NJL model where the condensate gives rise to an effective mass term?
- 1,783
5
votes
2
answers
1k
views
Origin of quark masses
Does all the mass of the quarks in the standard model come from the Higgs sector or is there also a contribution to quark masses due to QCD chiral symmetry breaking?
- 26.8k
4
votes
1
answer
547
views
Glueball mass in non-abelian Yang Mills theory
How can the glueball mass be calculated in Yang-Mills theory?
- 327