Photon rockets and the Robinson-Trautman geometries

TL;DR

This paper explores the connection between photon rocket spacetimes and Robinson-Trautman geometries, providing a geometric framework to distinguish gravitational and matter energy radiation and presenting an exact solution for generalized photon rockets.

Contribution

It establishes a geometric relation between photon rockets and Robinson-Trautman metrics, enabling clearer analysis of energy radiation and deriving a new exact solution.

Findings

Separated Weyl and Ricci radiations using asymptotic properties.

Provided an exact solution for generalized photon rockets.

Clarified gravitational energy content in these spacetimes.

Abstract

We point out the relation between the photon rocket spacetimes and the Robinson Trautman geometries. This allows a discussion of the issues related to the distinction between the gravitational and matter energy radiation that appear in these metrics in a more geometrical way, taking full advantage of their asymptotic properties at null infinity to separate the Weyl and Ricci radiations, and to clearly establish their gravitational energy content. We also give the exact solution for the generalized photon rockets.