Gravitational waves in modified teleparallel theories of gravity

TL;DR

This paper investigates gravitational wave polarization modes within various teleparallel gravity theories, revealing that under certain conditions, these modes match those predicted by General Relativity.

Contribution

It classifies gravitational wave polarizations in general teleparallel theories, extending previous results and identifying conditions for GR-like polarization modes.

Findings

Gravitational waves in certain teleparallel theories have the same polarization modes as GR.

The boundary term coupling influences polarization modes.

The study broadens understanding of wave polarizations in modified gravity theories.

Abstract

Teleparallel theory of gravity and its modifications have been studied extensively in literature. However, gravitational waves has not been studied enough in the framework of teleparallelism. In the present study, we discuss gravitational waves in general theories of teleparallel gravity containing the torsion scalar $T$, the boundary term $B$ and a scalar field $\phi$. The goal is to classify possible new polarizations generalizing results presented in Ref.[15]. We show that, if the boundary term is minimally coupled to the torsion scalar and the scalar field, gravitational waves have the same polarization modes of General Relativity.