Thermal Operator and Dispersion Relation in QED at Finite Temperature and Chemical Potential

TL;DR

This paper introduces a method combining thermal operator representation and dispersion relations to compute the retarded photon self-energy in finite-temperature QED with chemical potential, revealing that temperature-dependent effects vanish in 1+1 dimensional massless QED.

Contribution

It presents a novel approach to determine the retarded photon self-energy from its absorptive part at zero temperature in finite-temperature QED with chemical potential.

Findings

The temperature-dependent part of the one-loop retarded photon self-energy vanishes in 1+1 dimensional massless QED.

The method simplifies calculations by relating finite-temperature self-energy to zero-temperature absorptive parts.

The approach can be applied to analyze photon self-energy in various finite-temperature and chemical potential scenarios.

Abstract

Combining the thermal operator representation with the dispersion relation in QED at finite temperature and chemical potential, we determine the complete retarded photon self-energy only from its absorptive part at zero temperature. As an application of this method, we show that, even for the case of a nonzero chemical potential, the temperature dependent part of the one loop retarded photon self-energy vanishes in $(1+1)$ dimensional massless QED.