Spontaneous symmetry breaking in strong-coupling lattice QCD at high density

TL;DR

This paper investigates how spontaneous symmetry breaking patterns in strong-coupling lattice QCD depend on flavor number and baryon density, revealing symmetry reductions including lattice rotational symmetry breaking.

Contribution

It introduces a next-nearest-neighbor fermion formulation preserving continuum chiral symmetry and analyzes symmetry breaking patterns at various densities and flavor numbers.

Findings

Symmetry patterns depend on N_f and baryon density.

Ground state condensates break lattice rotational symmetry.

Discrete symmetries are broken alongside chiral symmetry.

Abstract

We determine the patterns of spontaneous symmetry breaking in strong-coupling lattice QCD in a fixed background baryon density. We employ a next-nearest-neighbor fermion formulation that possesses the SU(N_f)xSU(N_f) chiral symmetry of the continuum theory. We find that the global symmetry of the ground state varies with N_f and with the background baryon density. In all cases the condensate breaks the discrete rotational symmetry of the lattice as well as part of the chiral symmetry group.