Thermal effects on a global monopole with Robin boundary conditions

TL;DR

This paper investigates how thermal effects influence a global monopole spacetime with a naked singularity, focusing on boundary conditions and their impact on quantum field behavior and detector responses.

Contribution

It provides a detailed analysis of thermal quantum states and boundary conditions in a global monopole spacetime, highlighting the finiteness of physical quantities under Dirichlet conditions.

Findings

Transition rates depend on boundary conditions and temperature.

Finiteness of fluctuations and energy density occurs only with Dirichlet boundary conditions.

Thermal effects significantly influence quantum field behavior near the singularity.

Abstract

Within quantum field theory on a global monopole spacetime, we study thermal effects on a naked singularity and its relation with boundary conditions. We first obtain the two-points functions for the ground state and for thermal states of a massive, arbitrarily-coupled, free scalar field compatible with Robin boundary conditions at the singularity. We then probe these states using a static Unruh-Dewitt particle detector. The transition rate is analyzed for the particular cases of massless minimally or conformally coupled fields at finite temperature. To interpret the detector's behavior, we compute the thermal contribution to the ground-state fluctuations and to the energy density. We verify that the behavior of the transition rate, the fluctuations and the energy density are closely intertwined. In addition, we find that these renormalized quantities remain finite at the singularity for, and only for, Dirichlet boundary condition.