Twisted Gravitational Waves

TL;DR

This paper introduces a new class of exact solutions in general relativity describing nonplanar, twisted gravitational waves with nonuniform wave fronts, expanding the understanding of wave propagation beyond traditional plane waves.

Contribution

It presents the first known exact solutions for nonplanar, twisted gravitational waves propagating in a fixed direction in GR.

Findings

Identified a class of solutions with nonuniform wave fronts.

Characterized properties of twisted gravitational waves.

Extended the theoretical framework of gravitational wave solutions.

Abstract

In general relativity (GR), linearized gravitational waves propagating in empty Minkowski spacetime along a fixed spatial direction have the property that the wave front is the Euclidean plane. Beyond the linear regime, exact plane waves in GR have been studied theoretically for a long time and many exact vacuum solutions of the gravitational field equations are known that represent plane gravitational waves. These have parallel rays and uniform wave fronts. It turns out, however, that GR also admits exact solutions representing gravitational waves propagating along a fixed direction that are nonplanar. The wave front is then nonuniform and the bundle of rays is twisted. We find a class of solutions representing nonplanar unidirectional gravitational waves and study some of the properties of these twisted waves.