Induced Lorentz-violating terms at finite temperature

Abstract

We study the radiatively induced Lorentz-violating terms at finite temperature, namely, the higher-derivative term and the Chern-Simons term. These terms are induced by integrating out the fermions coupled to the coefficient gκμν. The calculation of the resulting expressions is performed by using the derivative expansion and the Matsubara formalism. The Chern-Simons term is nonzero only at finite temperature, whereas the higher-derivative term is finite at zero temperature; however, this latter goes to zero as the temperature grows to infinity. We also obtain a higher-derivative Chern-Simons term; nevertheless, it vanishes asymptotically.