Equivalence of light-front and conventional thermal field theory

TL;DR

This paper demonstrates that light-front thermal field theory is equivalent to conventional thermal field theory using spectral representations, allowing the use of conventional spectral functions to express light-front finite temperature propagators.

Contribution

It provides a proof of the equivalence between light-front and conventional thermal field theories applicable to all Lagrangians with spectral representations, and derives the light-front finite temperature fermion propagator.

Findings

Light-front and conventional thermal field theories are equivalent.

Conventional spectral functions can be used in light-front finite temperature calculations.

Derived the light-front finite temperature spin 1/2 fermion propagator.

Abstract

It is shown that light front thermal field theory is equivalent to conventional thermal field theory. The proof is based on the use of spectral representations, and applies to all Lagrangians for which such equivalence has been proven at zero temperature. It is also pointed out that conventional spectral functions can be used to express light-front finite temperature free propagators. As an application of our approach, we derive the light-front finite temperature spin 1/2 fermion propagator in full Dirac space.