English

Parity and CT realization in QCD

High Energy Physics - Theory 2009-10-31 v2 High Energy Physics - Lattice

Abstract

We show that an essential assumption in the Vafa and Witten's theorem on P and CT realization in vector-like theories, the existence of a free energy density in Euclidean space in the presence of any external hermitian symmetry breaking source, does not apply if the symmetry is spontaneously broken. The assumption that the free energy density is well defined requires the previous assumption that the symmetry is realized in the vacuum. Even if Vafa and Witten's conjecture is plausible, actually a theorem is still lacking.

Cite

@article{arxiv.hep-th/9901068,
  title  = {Parity and CT realization in QCD},
  author = {Vicente Azcoiti and Angelo Galante},
  journal= {arXiv preprint arXiv:hep-th/9901068},
  year   = {2009}
}

Comments

11 pages. Some comments added in the conclusions; final version to appear in Phys. Rev. Lett