Seminar of Hadron Physics

On 22 January 2016, at 11.00 am in Blokhintsev Hall (4 floor) a seminar “Chiral symmetry breaking, instantons, and monopoles” will be held. Authors: Adriano Di Giacomo (University of Pisa, Department of Physics and INFN) and Masayasu Hasegawa (BLTP, JINR).

Speaker: Masayasu Hasegawa (JINR BLTP)

Abstract

Our final goal is to show the relation between the chiral symmetry breaking and the quark confinement which is caused by the monopole condensation. In order to show the relation, we add one pair of monopoles with magnetic charges to QCD vacuum by a monopole creation operator, and investigate properties of the chiral symmetry breaking, using the Overlap fermion which preserves the chiral symmetry in the lattice gauge theory.

In previous work we have demonstrated that the additional monopoles form long loops, and create instantons in QCD vacuum [1]. In the study of the random matrix theory, we have found that the chiral condensate, which is the order parameter of the chiral symmetry breaking, decreases with increasing the magnetic charges of the additional monopoles [2]. That is to say that the monopoles are related with the chiral symmetry breaking.

However, these studies have mainly been done by adding monopoles to the small lattice volume and one lattice spacing. We have to check an influence of the finite lattice volume and discretization. Therefore, in the present work, we add monopoles with magnetic charges to the configurations of the larger lattice volumes and different parameters of lattice spacing, and study the relation between the chiral symmetry breaking, instantons, and monopoles [3].

In this seminar, I will introduce our research project, and present the results indicating that the monopoles are related with instantons and the chiral symmetry breaking.

[1] A. Di Giacomo and M. Hasegawa, Instantons and monopoles, Phys. Rev. D 91 (2015) 054512.

[2] A. Di Giacomo, M. Hasegawa, and F. Pucci, Chiral symmetry breaking and monopoles, arXiv:hep-lat/1510.07463 (2015), (PoS (CD15) 127).

[3] A. Di Giacomo and M. Hasegawa, Chiral symmetry breaking, instantons, and monopoles, arXiv:hep-lat/1512.00359 (2015), (PoS (LATTICE 2015) 313).