On "time-periodic" black-hole solutions to certain spherically symmetric Einstein-matter systems

TL;DR

This paper investigates time-periodic black hole solutions in spherically symmetric Einstein-matter systems, showing that under certain conditions, solutions are Schwarzschild or Reissner-Nordstrom, and that Dirac fields must vanish in these settings.

Contribution

It extends previous static black hole uniqueness results to the time-periodic case and proves Dirac fields must vanish in certain spherically symmetric Einstein-matter systems.

Findings

Time-periodic solutions are Schwarzschild or Reissner-Nordstrom under specified conditions.

Dirac fields must vanish in the considered spherically symmetric domains.

Results generalize previous static case work to periodic and dynamic scenarios.

Abstract

This paper explores ``black hole'' solutions of various Einstein-wave matter systems admitting an isometry of their domain of outer communications taking every point to its future. In the first two parts, it is shown that such solutions, assuming in addition that they are spherically symmetric and the matter has a certain structure, must be Schwarzschild or Reissner-Nordstrom. Non-trivial examples of matter for which the result applies are a wave map and a massive charged scalar field interacting with an electromagnetic field. The results thus generalize work of Bekenstein [1] and Heusler [12] from the static to the periodic case. In the third part, which is independent of the first two, it is shown that Dirac fields preserved by an isometry of a spherically symmetric domain of outer communications of the type described above must vanish. It can be applied in particular to the Einstein-Dirac-Maxwell equations or the Einstein-Dirac-Yang/Mills equations, generalizing work of Finster, Smoller, and Yau [9], [7], [8], and also [6].