Rings of light caused by gravitational waves

TL;DR

This paper analyzes how gravitational waves can produce rings of light observable over large distances, using a simplified Lagrangian approach that revises previous calculations.

Contribution

It introduces a new interpretation of gravitational wave effects on light, demonstrating potential observability over large distances with a simplified method.

Findings

Rings of light can be caused by gravitational waves.

The new approach simplifies calculations of test particle motion.

Potential observability of these effects over large distances.

Abstract

We reconsider the case of the geodesic motion of a massive and massless beam of test particles in a gravitational wave. In particular, we use a direct Lagrangian approach which simplifies the calculation. Our findings differ partly from previously performed calculations The final result can be interpreted as rings of light seen by the observer. We give a new interpretation to this picture and show that over large distances the effect, albeit rare, could in principle be observable.