Self-force on a scalar particle in a class of wormhole spacetimes

TL;DR

This paper analyzes the self-force on scalar particles in wormhole spacetimes, revealing how it varies with coupling and throat profile, and providing a general method applicable to different wormhole geometries.

Contribution

It introduces a general approach to compute the self-force in wormhole spacetimes and explores its behavior for various throat profiles and coupling constants.

Findings

Self-force changes sign at nonminimal coupling ξ=1/8.

Self-force tends to infinity at specific ξ values.

Results recover electromagnetic case for massless particles with minimal coupling.

Abstract

We consider the self-energy and the self-force for scalar massive and massless particles at rest in the wormhole space-time. We develop a general approach to obtain the self-force and apply it to the two specific profiles of the wormhole throat, namely, with singular and with smooth curvature. We found that the self-force changes its sign at the point where nonminimal coupling $\xi = 1/8$ (for massless case) and it tends to infinity for specific values of $\xi$. It may be attractive as well repulsive depending on the profile of the throat. For massless particle and minimal coupling case the electromagnetic results are recovered.