In other threads it has been discussed whether the gravitational constant G could be diminishing over time, as Dirac had proposed. Dirac's idea was premised on the Big Bang-type cosmology. In a static model we would not imagine that G was decreasing on a universal basis. Yet some lines of evidence suggest that the gravitational force is indeed getting weaker over time. What could be causing this?
What if the gravitational potential energy of a body or a system of bodies were in the form of electromagnetic energy? Then this energy might be subject to a cosmic redshift effect identical to the redshift causing 'tired light' in static models. We could liken the attractive force between two masses to elastic bands attaching them together, which weaken and break over time.
A question though. The gravitational potential energy, U, is ordinarily considered to be negative. When two bodies are separated by infinite distance it is said to be zero. What is happening to U in my system above? When two bodies like the Moon and the Earth become more separated over time, is U decreasing, increasing or staying the same?