The concept of variable mass appears in special relativity. There the mass of a body is increased by its velocity and so fluctuates if the body moves in an eccentric orbit. Mach's Principle also employs additional mass, but this is caused by the mass and distance of a neighboring body. In earlier work, the fluctuating mass which varies inversely with the distance between bodies was introduced. The orbital precession of the binary pulsar PSR 1913+16 was then successfully correlated with the quite different precessions of Mercury and the other inner planets.
In the present work, a delay in adjusting gravitational force between elements of fluctuating mass is used to calculate energy loss and rate of change of period for PSR 1913+16. It is surprising that this extended use of the additional mass concept gives results of the correct order for rate of change of period and also gives the same dependence on mass and period as that shown by general relativity.
The orbital precession of the binary pulsar PSR 1913+16 can be related to the quite different precessions of Mercury and other inner planets by one simple formula. Expressed non-dimensionally as degrees of prrecession per degree of orbit, the orbit precession rate is given by 3(M0Ma0 / Htot)2 (G/c)2 . Here M0 and Ma0 are the masses of the pulsar and its companion, or of the planet and the sun, as the case may be. The Htot is the total angular momentum of the system, G is the gravitational constant and c is the speed of light. The formula is obtained by postulating mass increase proportional to the inverse of the distance between bodies.