Gravitational wave signal from massive gravity

TL;DR

This paper explores how stochastic gravitational wave observations can detect signals from massive gravity theories, characterized by a time-dependent mass term that creates a distinctive peak in the spectrum, revealing details about the universe's inflationary history.

Contribution

It provides a universal analysis framework for massive gravity effects on gravitational waves, focusing on the spectral peak's features and their observational implications.

Findings

A sharp peak in the gravitational wave spectrum indicates a massive gravity effect.

The peak's position and height relate to the current mass value and inflation duration.

Future gravitational wave observatories could detect these signals.

Abstract

We discuss the detectability of gravitational waves with a time dependent mass contribution, by means of the stochastic gravitational wave observations. Such a mass term typically arises in the cosmological solutions of massive gravity theories. We conduct the analysis based on a general quadratic action, and thus the results apply universally to any massive gravity theories in which modification of general relativity appears primarily in the tensor modes. The primary manifestation of the modification in the gravitational wave spectrum is a sharp peak. The position and height of the peak carry information on the present value of the mass term, as well as the duration of the inflationary stage. We also discuss the detectability of such a gravitational wave signal using the future-planned gravitational wave observatories.