Untangling scaling dimensions of fixed charge operators in Higgs Theories

TL;DR

This paper develops a new semiclassical method to determine the scaling dimensions of fixed-charge operators in complex symmetry groups like U(N)×U(M), enabling analysis of a broad class of operators in conformal field theories.

Contribution

It introduces a general strategy for relating charge configurations to operators in non-abelian groups, extending beyond previous semiclassical approaches.

Findings

Computed anomalous dimensions for various operators in U(N)×U(M) CFTs.

Demonstrated the method's ability to access a wide range of operator dimensions.

Achieved next-to-leading order accuracy in 4-ε dimensions.

Abstract

We go beyond a systematic review of the semiclassical approaches for determining the scaling dimensions of fixed-charge operators in $U(1)$ and $O(N)$ models by introducing a general strategy apt at determining the relation between a given charge configuration and the associated operators for more involved symmetry groups such as the $U(N) \times U(M)$. We show how, varying the charge configuration, it is possible to access anomalous dimensions of different operators transforming according to a variety of irreducible representations of the non-abelian symmetry group without the aid of diagrammatical computations. We illustrate our computational strategy by determining the anomalous dimensions of several composite operators to the next-to-leading order in the semiclassical expansion for the $U(N) \times U(M)$ conformal field theory (CFT) in $4-\epsilon$ dimensions. Thanks to the powerful interplay between semiclassical methods and group theory we can, for the first time, extract scaling dimensions for a wide range of operators.