Domain walls in supersymmetric QCD: The taming of the zoo

TL;DR

This paper analyzes the spectrum of domain walls in supersymmetric QCD with varying quark masses and ratios of flavors to colors, revealing critical masses where the nature and number of BPS and non-BPS walls change.

Contribution

It provides a unified analysis of domain wall behavior in supersymmetric QCD across different flavor-to-color ratios, including numerical determination of critical masses.

Findings

For Nf/Nc<1/2, one BPS domain wall exists regardless of quark mass.

For 1/2<=Nf/Nc<1, two critical masses m* and m** determine the number and type of domain walls.

m** approaches a constant as Nf/Nc approaches 1.

Abstract

We provide a unified picture of the domain wall spectrum in supersymmetric QCD with Nc colors and Nf flavors of quarks in the (anti-) fundamental representation. Within the framework of the Veneziano-Yankielowicz-Taylor effective Lagrangian, we consider domain walls connecting chiral symmetry breaking vacua, and we take the quark masses to be degenerate. For Nf/Nc<1/2, there is one BPS saturated domain wall for any value of the quark mass m. For 1/2=<Nf/Nc<1 there are two critical masses, m* and m**, which depend on the number of colors and flavors only through the ratio Nf/Nc; if m<m*, there are two BPS walls, if m*<m<m** there is one non-BPS wall, and if m>m** there is no domain wall. We numerically determine m* and m** as a function of Nf/Nc, and we find that m** approaches a constant value in the limit that this ratio goes to one.