New Constraints on Chiral Gauge Theories

TL;DR

This paper explores a new inequality constraint on strongly coupled chiral gauge theories, revealing its universal validity in some models and its restrictive implications on the spectrum of massless composites in others.

Contribution

It applies a recently proposed inequality to chiral gauge theories, providing new insights into their infrared degrees of freedom and spectrum restrictions.

Findings

The inequality is always satisfied in certain models.

In some cases, the inequality imposes strong restrictions on massless composite particles.

The results help refine understanding of strongly coupled chiral gauge theories.

Abstract

Recently, a new constraint on the structure of a wide class of strongly coupled field theories has been proposed. It takes the form of an inequality limiting the number of degrees of freedom in the infrared description of a theory to be no larger than the number of underlying, ultraviolet degrees of freedom. Here we apply this inequality to chiral gauge theories. For some models we find that it is always satisfied, while for others we find that the assumption of the validity of the inequality implies a strong additional restriction on the spectrum of massless composite particles.