Related Experiment Video
Updated: Jun 3, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
On the unreasonable effectiveness of the post-Newtonian approximation in gravitational physics
1Department of Physics, McDonnell Center for the Space Sciences, Washington University, St Louis, MO, USA. cmw@wuphys.wustl.edu
Abstract:
The post-Newtonian approximation is a method for solving Einstein's field equations for physical systems in which motions are slow compared to the speed of light and where gravitational fields are weak. Yet it has proven to be remarkably effective in describing certain strong-field, fast-motion systems, including binary pulsars containing dense neutron stars and binary black hole systems inspiraling toward a final merger. The reasons for this effectiveness are largely unknown. When carried to high orders in the post-Newtonian sequence, predictions for the gravitational-wave signal from inspiraling compact binaries will play a key role in gravitational-wave detection by laser-interferometric observatories.
Related Concept Videos
Newton's Law of Gravitation
Space-Time Curvature and the General Theory of Relativity
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of motion,...
Principle of Equivalence
Newton's Law of Gravitational Attraction
Newton's law of gravitational attraction is a fundamental law of physics that governs the attraction between objects. It states that the magnitude of the gravitational force between any two objects is proportional to their masses and inversely proportional...
Gravitation
Newton's First Law: Introduction

