| 摘要: |
This paper addresses two aspects concerning the -vacuum of Quantum Chro-modynamics. First, large-N-c chiral perturbation theory is used to calculate the first two non-trivial cumulants of the distribution of the winding number, i.e. the topological susceptibility, (top), and the fourth cumulant, c(4), up to next-to-leading order. Their large-N-c scaling is discussed, and compared to lattice results. It is found that in the literature. Second, we discuss the properties of QCD at approximate to using chiral perturbation theory for the case of 2 + 1 light flavors, i.e. by taking the strange quark mass heavier than the degenerate up and down quark masses. It is shown that in accordance with previous findings for N-f = 2 and N-f = 3 mass-degenerate flavors in the region approximate to two vacuum states coexist, which become degenerate at = . The wall tension of the energy barrier between these degenerate vacua is determined as well as the decay rate of a false vacuum. |
