A New Constraint on Strongly Coupled Field Theories

TL;DR

This paper introduces a new inequality constraint on strongly coupled field theories, limiting their infrared degrees of freedom relative to ultraviolet ones, with broad applications and connections to RG c-theorems.

Contribution

It presents a novel inequality constraint on strongly coupled theories, applicable to both supersymmetric and nonsupersymmetric cases, enhancing understanding of their low-energy spectra.

Findings

The inequality agrees with all known results for tested theories.

It provides new constraints on low energy spectra.

It relates to Renormalization Group c-theorems.

Abstract

We propose a new constraint on the structure of strongly coupled field theories. The constraint takes the form of an inequality limiting the number of degrees of freedom in the infrared description of a theory relative to the number of underlying, ultraviolet degrees of freedom. We apply the inequality to a variety of theories (both supersymmetric and nonsupersymmetric), where it agrees with all known results and leads to interesting new constraints on low energy spectra. We discuss the relation of this constraint to Renormalization Group c-theorems.