Vacuum polarization of a quantized scalar field in the thermal state in a long throat

Abstract

Vacuum polarization of scalar fields in the background of a long throat is investigated. The field is assumed to be both massive or massless, with arbitrary coupling to the scalar curvature, and in a thermal state at an arbitrary temperature. Analytical approximation for $\left< \varphi^2 \right>_{ren}$ is obtained.Comment: 20 page