Strong-field point-particle limit and the equations of motion in the binary pulsar.

Abstract

We construct an asymptotic approximation in general relativity to a binary system of two neutron stars by taking a point-particle limit along a sequence of spacetimes. A detailed calculation of the near-zone field is performed in radiation-reaction order. We calculate the rate of change of Newtonian energy and the angular momentum. The result coincides with the standard formula. The equation of spin precession is also calculated and the same result as for weak gravity is obtained. We thus extend the strong equivalence principle for bodies with strong internal gravity to the generation of gravitational radiation and the spin precession.