Snowmass White Paper: Gravitational Waves and Scattering Amplitudes

Abstract

We review recent progress and future prospects for harnessing powerful tools from theoretical high-energy physics, such as scattering amplitudes and effective field theory, to develop a precise and systematically improvable framework for calculating gravitational-wave signals from binary systems composed of black holes and/or neutron stars. This effort aims to provide state-of-the-art predictions that will enable high-precision measurements at future gravitational-wave detectors. In turn, applying the tools of quantum field theory in this new arena will uncover theoretical structures that can transform our understanding of basic phenomena and lead to new tools that will further the cycle of innovation. While still in a nascent stage, this research direction has already derived new analytic results in general relativity, and promises to advance the development of highly accurate waveform models for ever more sensitive detectors.

Effective field theories of gravity and compact binary dynamics: A Snowmass 2021 whitepaper

“…This has stimulated a flurry of theoretical activity, reviewed in ref. [107]. Given the promising experimental situation in gravitational wave astronomy, it is a safe bet to expect sustained growth in the years to come at the confluence of on-shell amplitudes, classical general relativity, and the EFT approach to compact binary mergers…”

“…Conservative and radiative dynamics in PM scattering has been an active area of recent effort that has brought together theoretical approaches from diverse communities, including researchers working on scattering amplitudes and formal theory, general relativity, and on effective field theories. See the Snowmass whitepaper [107] for a review and a complete set of references.…”

Snowmass White Paper: Higher Spin Gravity and Higher Spin symmetry

“…an expansion in Newton's constant). A full account of the application of amplitude methods to calculations related to gravitational-wave physics is beyond the scope of this paper; the interested reader should refer to the white paper [297] (see also Ref. [298] for an overview of modern methods for amplitudes in gravity).…”

Gravitational bremsstrahlung from spinning binaries in the post-Minkowskian expansion

“…In recent years, rapid advancements in the PM program have been driven by the scattering amplitudes community [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39], who (at present) have pushed out calculations in the conservative sector up to 4PM; i.e., up to 𝑂(𝐺 4 ) [40,41]. Analogous results, obtained independently through various worldline effective field theory (EFT) approaches, followed shortly thereafter [42][43][44][45][46][47].…”