Understand
The "external" or "bulk" motion of extended bodies is studied in general relativity.
- Compact material objects of essentially arbitrary shape, spin, internal composition, and velocity are allowed as long as there is no direct (non-gravitational) contact with other sources of stress-energy.
- Physically reasonable linear and angular momenta are proposed for such bodies and exact equations describing their evolution are derived.
- Changes in the momenta depend on a certain "effective metric" that is closely related to a non-perturbative generalization of the Detweiler-Whiting R-field originally introduced in the self-force literature.
Reading the bibliography…