Quantum gravitational optics in the field of a gravitomagnetic monopole

TL;DR

This paper explores how quantum effects in gravitational fields, specifically in NUT space with a gravitomagnetic monopole, alter the classical behavior of light rays as null geodesics.

Contribution

It provides a detailed analysis of quantum gravitational optics effects in NUT space, a novel application of vacuum polarization in a gravitomagnetic monopole background.

Findings

Quantum vacuum polarization modifies light propagation in NUT space.

The classical null geodesic picture is effectively altered by quantum effects.

The study offers insights into quantum gravity phenomena in complex spacetimes.

Abstract

Vacuum polarization in QED in a background gravitational field induces interactions which {\it effectively} modify the classical picture of light rays as the null geodesics of spacetime. After a short introduction on the main aspects of the quantum gravitational optics, as a nontrivial example, we study this effect in the background of NUT space characterizing the spacetime of a spherical mass endowed with a gravitomagnetic monopole charge, the so called NUT factor.