Cosmic string interactions induced by gauge and scalar fields

TL;DR

This paper investigates how gauge and scalar fields with non-minimal couplings induce interactions between parallel cosmic strings, revealing equivalences and implications for black hole entropy renormalization.

Contribution

It demonstrates the equivalence of gauge fields to non-minimal scalars in small deficit angles and computes the interaction energy at first order, providing new insights into string interactions.

Findings

Gauge fields behave like non-minimal scalars at small deficit angles

Interaction energy between strings is computed at first order

Results relate to contact terms in black hole entropy renormalization

Abstract

We study the interaction between two parallel cosmic strings induced by gauge fields and by scalar fields with non-minimal couplings to curvature. For small deficit angles the gauge field behaves like a collection of non-minimal scalars with a specific value for the non-minimal coupling. We check this equivalence by computing the interaction energy between strings at first order in the deficit angles. This result provides another physical context for the "contact terms" which play an important role in the renormalization of black hole entropy due to a spin-1 field.