Radiative Corrections for the Gauged Thirring Model in Causal Perturbation Theory

TL;DR

This paper computes one-loop fermion self-energy corrections in the gauged Thirring model using causal perturbation theory, revealing finite two-point functions and discussing causality's role in nonrenormalizable theories.

Contribution

It provides the first detailed analysis of radiative corrections in the gauged Thirring model within the causal perturbation framework, highlighting differences from QED3.

Findings

Two-point function is infrared finite on the mass shell.

Derived on-shell vertex correction via Ward identity.

Discussed causality's impact on nonrenormalizable theories.

Abstract

We evaluate the one-loop fermion self-energy for the gauged Thirring model in (2+1) dimensions, with one massive fermion flavor, in the framework of the causal perturbation theory. In contrast to QED$_3$, the corresponding two-point function turns out to be infrared finite on the mass shell. Then, by means of a Ward identity, we derive the on-shell vertex correction and discuss the role played by causality for nonrenormalizable theories.