Chiral symmetry restoration at large chemical potential in strongly coupled SU(N) gauge theories

TL;DR

This paper demonstrates that at high chemical potential, strongly coupled SU(N) gauge theories with staggered fermions exhibit chiral symmetry restoration, using a polymer cluster expansion method that converges at large  and temperature.

Contribution

The authors introduce a polymer cluster expansion approach to prove chiral symmetry restoration at large chemical potential in strongly coupled SU(N) gauge theories.

Findings

Chiral symmetry is restored at large chemical potential.

The cluster expansion converges at any temperature for sufficiently large .

Expectations of chirally non-invariant operators vanish in the large  limit.

Abstract

We show that at sufficiently large chemical potential SU(N) lattice gauge theories in the strong coupling limit with staggered fermions are in a chirally symmetric phase. The proof employs a polymer cluster expansion which exploits the anisotropy between timelike and spacelike directions in the presence of a quark chemical potential $\mu$. The expansion is shown to converge in the infinite volume limit at any temperature for sufficiently large $\mu$. All expectations of chirally non-invariant local fermion operators vanish identically, or, equivalently, their correlations cluster exponentially, within the expansion. The expansion itself may serve as a computational tool at large $\mu$ and strong coupling.