Post-Newtonian Theory and its Application

TL;DR

This paper reviews recent advances in post-Newtonian theory for slowly-moving sources, focusing on gravitational radiation from binary systems, and compares analytical predictions with numerical relativity results, questioning some existing waveform models.

Contribution

It provides updated 3PN and 3.5PN calculations for binary dynamics and gravitational waves, and evaluates the innermost circular orbit, challenging the applicability of Schwarzschild-like templates.

Findings

3PN and 3.5PN accurate gravitational wave fluxes

Good agreement between 3PN ICO and numerical relativity

Questioning the validity of Schwarzschild-like templates for inspiral

Abstract

We review some recent works on the post-Newtonian theory of slowly-moving (post-Newtonian) sources, and its application to the problems of dynamics and gravitational radiation from compact binary systems. Our current knowledge is 3PN on the center-of-mass energy and 3.5PN on the gravitational-wave flux of inspiralling compact binaries. We compute the innermost circular orbit (ICO) of binary black-hole systems and find a very good agreement with the result of numerical relativity. We argue that the gravitational dynamics of two bodies of comparable masses in general relativity does not resemble that of a test particle on a Schwarzschild background. This leads us to question the validity of some ``Schwarzschild-like'' templates for binary inspiral which are constructed from post-Newtonian resummation techniques.