  It is assumed that the primary interaction between two masses m1 and m2 is
not attractive as postulated by Newton's law of gravitation, but repulsive.
Both m1 and m2 emit and absorb gravitational radiation. Corresponding to the
laws of optics the absorption is connected with an impulse transfer that
produces the repulsive force. If, however, m1 and m2 are embedded in the
gravitational radiation produced by all the masses of the universe the
absorption by m1 and m2 leads to a reduction of the intensity of the
gravitational radiation between them, thus creating an attractive force exactly
as described by Newton's law. The so called universal gravitational constant is
no constant. It locally depends on the arrangement of the masses in the
universe. It can accept high values which are usually explained by the
existence of dark matter. Due to the primary forces of repulsive nature between
all masses the expansion of the universe is an intrinsic property. The balance
between primary, repulsive and secondary, attractive gravitational forces can
stabilize highly concentrated mass accumulations as they are observed in
globular clusters and the bulges of galaxies.
