Ġ/G and a cosmological acceleration of gravitationally compact bodies

The mass of bodies with appreciable gravitational self-energy vary in time at a rate proportional to any time variation of the gravitational coupling parameter G. As a result of these mass variations, gravitationally compact bodies will experience anomalous accelerations proportional to their motion relative to the cosmological rest frame in which G=G(t). These effects alter the relationship between the rate of change of orbital period for compact bodies and the rate of change, if any, of G. The binary pulsar system PSR 1913+16 is consequently found to be a somewhat less sensitive probe of a possible nonzero Ġ/G than has been suggested.