Testing General Relativity with Gravitational Waves

TL;DR

This paper reviews how gravitational wave observations are used to test Einstein's General Relativity, focusing on three main theory-agnostic methods and discussing future challenges.

Contribution

It provides an overview of current testing methods for gravity using gravitational waves and discusses how these can be applied to modified theories of gravity.

Findings

Three main theory-agnostic tests are described.

Application of tests to modified gravity theories is explained.

Open questions for improving tests are identified.

Abstract

Gravitational-wave sources offer us unique testbeds for probing strong-field, dynamical and nonlinear aspects of gravity. In this chapter, we give a brief overview of the current status and future prospects of testing General Relativity with gravitational waves. In particular, we focus on three theory-agnostic tests (parameterized tests, inspiral-merger-ringdown consistency tests, and gravitational-wave propagation tests) and explain how one can apply such tests to example modified theories of gravity. We conclude by giving some open questions that need to be resolved to carry out more accurate tests of gravity with gravitational waves.