2011

On the unreasonable effectiveness of the post-Newtonian approximation in gravitational physics

Will, Clifford M.

Understand

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.

Reading the bibliography…