Axisymmetric electrovacuum spacetimes with an additional Killing vector and radiation

TL;DR

This paper investigates symmetries in axially symmetric electrovacuum spacetimes, identifying conditions under which these spacetimes can admit radiation and be asymptotically flat, focusing on the role of boost symmetries.

Contribution

It characterizes allowable additional symmetries in axially symmetric electrovacuum spacetimes, highlighting the unique role of boost symmetry in permitting radiation.

Findings

Boost symmetry allows for radiation and asymptotic flatness.

Translational symmetries are also possible but exclude radiation.

The study clarifies symmetry constraints in electrovacuum spacetimes.

Abstract

Main results concerning allowable additional symmetries of axially symmetric electrovacuum spacetimes are summarized. These are translational Killing vectors and the boost Killing vector. However, this is only the boost symmetry that does not exclude radiation and permit a spacetime to be asymptotically flat with global null infinity.