A Review of Gravitational Memory and BMS Frame Fixing in Numerical Relativity

TL;DR

This paper reviews how gravitational memory effects and BMS symmetries are incorporated into numerical relativity, enhancing gravitational wave models and enabling new tests of general relativity and astrophysics.

Contribution

It provides a comprehensive review of memory effects and BMS symmetries, emphasizing their role in improving numerical relativity simulations and gravitational wave modeling.

Findings

Memory effects and BMS symmetries improve waveform accuracy.

Controlling BMS freedoms enhances gravitational wave predictions.

Next-generation waveforms can reveal new physics and astrophysical insights.

Abstract

Gravitational memory effects and the BMS freedoms exhibited at future null infinity have recently been resolved and utilized in numerical relativity simulations. With this, gravitational wave models and our understanding of the fundamental nature of general relativity have been vastly improved. In this paper, we review the history and intuition behind memory effects and BMS symmetries, how they manifest in gravitational waves, and how controlling the infinite number of BMS freedoms of numerical relativity simulations can crucially improve the waveform models that are used by gravitational wave detectors. We reiterate the fact that, with memory effects and BMS symmetries, not only can these next-generation numerical waveforms be used to observe never-before-seen physics, but they can also be used to test GR and learn new astrophysical information about our universe.