Harmonic gauge perturbations of the Schwarzschild metric

Understand

The satellite observatory LISA will be capable of detecting gravitational waves from extreme mass ratio inspirals (EMRIs), such as a small black hole orbiting a supermassive black hole.

• The gravitational effects of the much smaller mass can be treated as the perturbation of a known background metric, here the Schwarzschild metric.
• The perturbed Einstein field equations form a system of ten coupled partial differential equations.
• We solve the equations in the harmonic gauge, also called the Lorentz gauge or Lorenz gauge.