de Sitter Teukolsky waves

TL;DR

This paper introduces linearized quadrupolar gravitational waves in de Sitter spacetime, demonstrating their properties and energy flux, and connecting to existing solutions in the zero cosmological constant limit.

Contribution

It presents de Sitter Teukolsky waves, a new class of solutions for gravitational perturbations in de Sitter space, extending previous work and analyzing their energy flux.

Findings

Solutions match Teukolsky solutions as $\Lambda$ approaches zero

Energy flux across $\mathcal{I}^{+}$ is positive

Comparison with existing literature on gravitational perturbations

Abstract

We present de Sitter Teukolsky waves -- linearised quadrupolar gravitational waves in the transverse-traceless gauge in de Sitter spacetime. In the cosmological constant $\Lambda$ going to zero limit, our solutions match to Teukolsky solutions. For non-zero $\Lambda$, we compare our solutions to the wider literature, where different authors have constructed linearised gravitational perturbations in de Sitter spacetime with varied motivations. For de Sitter Teukolsky waves, we compute the energy flux across future timelike infinity $\mathcal{I}^{+}$ and show that it is manifestly positive.