Gravitational waves and electrodynamics: New perspectives

TL;DR

This paper investigates how gravitational waves interact with electromagnetic fields, revealing new polarization effects and potential methods to enhance detection sensitivity, which could advance understanding of energetic GW sources.

Contribution

It introduces a theoretical framework for electromagnetic-GW coupling on (pseudo) Riemannian manifolds, highlighting novel polarization modes and potential amplification techniques for detection.

Findings

Longitudinal electromagnetic modes induced by GWs

Dynamical polarization patterns in electromagnetic radiation

Possible enhancement of signals using resonators

Abstract

Given the recent direct measurement of gravitational waves (GWs) by the LIGO-VIRGO collab- oration, the coupling between electromagnetic fields and gravity have a special relevance since it opens new perspectives for future GW detectors and also potentially provides information on the physics of highly energetic GW sources. We explore such couplings using the field equations of electrodynamics on (pseudo) Riemann manifolds and apply it to the background of a GW, seen as a linear perturbation of Minkowski geometry. Electric and magnetic oscillations are induced that propagate as electromagnetic waves and contain information about the GW which generates them. The most relevant results are the presence of longitudinal modes and dynamical polarization patterns of electromagnetic radiation induced by GWs. These effects might be amplified using appropriate resonators, effectively improving the signal to noise ratio around a specific frequency. We also briefly address the generation of charge density fluctuations induced by GWs and the implications for astrophysics.