Bounds on the renormalized couplings in an SU(2)_L \otimes SU(2)_R symmetric Yukawa model

TL;DR

This paper investigates bounds on Higgs boson mass and fermion couplings within an $SU(2)_L imes SU(2)_R$ symmetric Yukawa model, finding good agreement with perturbation theory even at strong couplings.

Contribution

It provides numerical bounds on Higgs and fermion masses in a symmetric Yukawa model, including analysis of renormalized couplings and reflection positivity constraints.

Findings

Good agreement with perturbation theory at strong couplings

Numerical bounds on Higgs and fermion masses established

Upper bounds on fermion mass and Yukawa coupling determined

Abstract

The vacuum stability lower bound on the mass of the Higgs boson is numerically investigated in an $SU(2)_L \otimes SU(2)_R$ symmetric Yukawa model, which describes two heavy degenerate fermion doublets in the limit of vanishing gauge couplings. Good agreement with perturbation theory is found, although the couplings are strong. The upper bound on the fermion mass and renormalized Yukawa coupling is also determined in the part of bare parameter space where reflection positivity has been proven.