SU(4) lattice gauge theory with decuplet fermions: Schr\"odinger functional analysis

TL;DR

This study numerically investigates SU(4) gauge theory with decuplet fermions, finding a slow-running beta function and a moderate mass anomalous dimension, with notable large-N regularities, informing beyond-Standard-Model physics.

Contribution

It provides the first non-perturbative Schrödinger functional analysis of SU(4) with decuplet fermions, extending previous work on SU(2) and SU(3).

Findings

Beta function runs more slowly than two-loop perturbation theory.

Mass anomalous dimension saturates around 0.45 at strong coupling.

Large-N comparison reveals regularities across SU(2), SU(3), and SU(4).

Abstract

We complete a program of study of SU(N) gauge theories coupled to two flavors of fermions in the two-index symmetric representation by performing numerical simulations in SU(4). The beta function, defined and calculated via the Schr\"odinger functional, runs more slowly than the two-loop perturbative result. The mass anomalous dimension levels off in strong coupling at a value of about 0.45, rendering this theory unsuitable for walking technicolor. A large-N comparison of this data with results from SU(2) and SU(3) reveals striking regularities.