Massless DKP fields in Riemann-Cartan space-times

TL;DR

This paper investigates massless DKP fields in Einstein-Cartan space-times, revealing how torsion affects gauge symmetries and drawing parallels with electromagnetic theory.

Contribution

It demonstrates the impact of torsion on gauge symmetries of massless DKP fields within Einstein-Cartan gravity, extending understanding of gauge invariance in curved space-times.

Findings

Vanishing torsion preserves usual gauge symmetries.

Non-vanishing torsion generally breaks U(1) gauge invariance.

Conditions on torsion are necessary for gauge symmetry preservation.

Abstract

We study massless Duffin-Kemmer-Petiau (DKP) fields in the context of Einstein-Cartan gravitation theory, interacting via minimal coupling procedure. In the case of an identically vanishing torsion (Riemannian space-times) we show that there exists local gauge symmetries which reproduce the usual gauge symmetries for the massless scalar and electromagnetic fields. On the other hand, similarly to what happens with the Maxwell theory, a non-vanishing torsion, in general, breaks the usual U(1) local gauge symmetry of the electromagnetic field or, in a different point of view, impose conditions on the torsion.