Infrared fixed point in SU(2) gauge theory with adjoint fermions

TL;DR

This study investigates the infrared behavior of SU(2) gauge theory with two adjoint fermions using lattice techniques, providing evidence for an infrared fixed point and measuring the associated anomalous dimension.

Contribution

The paper introduces hypercubic smearing in Schrödinger-functional methods to explore stronger couplings and identifies an infrared fixed point in SU(2) with adjoint fermions.

Findings

Evidence of an infrared fixed point at g* with 1/g*^2 ≈ 0.20

Measured mass anomalous dimension gamma_m(g*) ≈ 0.31

Ability to work at stronger couplings than previous studies

Abstract

We apply Schrodinger-functional techniques to the SU(2) lattice gauge theory with N_f=2 flavors of fermions in the adjoint representation. Our use of hypercubic smearing enables us to work at stronger couplings than did previous studies, before encountering a critical point and a bulk phase boundary. Measurement of the running coupling constant gives evidence of an infrared fixed point g* where 1/g*^2 = 0.20(4)(3). At the fixed point, we find a mass anomalous dimension gamma_m(g*) = 0.31(6).