Even though gravity is still the least understood of the four fundamental forces of our universe, is there any evidence that the force of gravity is actually getting weaker?
By: Ringo Bones
When compared to the other fundamental forces of the universe – i.e. the strong and weak forces and the electromagnetic force, the force of gravity is currently the least understood. Until the results of the experiments done at the Large Hadron Collider at CERN makes us gain a handle on String Theory, Albert Einstein’s Theory General of Relativity is the best one yet explaining how gravity works. But is there any evidence that the force of gravity is actually getting weaker?
There have been many challenges to Albert Einstein’s Theory of General Relativity since its presentation in 1916 – all of them unsuccessful. But that record did not daunt astronomer Thomas C. Van Flandern a researcher at the US Naval Observatory, who back in 1974 found evidence of what he believes is the gradual weakening of gravity, a force that according to General Relativity never varies.
Van Flandern’s evidence is based on the motion of celestial objects, which would be affected by a change in gravitational force. By studying the precise times that the moon has blocked from view various stars over the past 19 years, Van Flandern calculated the changes in the moon’s orbital velocity. The rate, Van Flandern said, was twice the amount of slowdown that would be expected from known causes, principally the mutual tugs of the tides on earth and moon. The difference could be accounted for by a decrease of the force of gravity of one part in 10-billion per year.
A discrepancy in the changes in the earth’s rotation, also caused by the tidal effects, could similarly be explained by a decrease in gravitational force, according to Van Flandern. The same gradual phenomenon may even account for a gradual increase in the size of the earth and thus explain such geological phenomena as sea-floor spreading and the movements of crustal plates.
Thomas Van Flandern is not the only one who finds Einstein’s General Relativity wanting. The late physicist Paul Dirac also conjectured that that the universal force of gravity is slowly decreasing. And the idea that the universal force of gravity is gradually decreasing even gave the idea to science writer Robert Schadewald who back in April 1978 wrote an article about his “Schadewald Gravity Engine” the first true working energy generating device that works on the principle of perpetual motion.