The purpose of the present paper is to assume that the expanding
spacetime of our cosmos was created by the big bang. It then follows that there
exists a finite instantaneous radial extent dRU to spacetime as observed from anywhere in spacetime by comoving observers. The
consequences for gravity are explored by first considering the scalar field of
a central mass that defines the dynamic properties of a circular orbit for each
radius R ≤ dRU under the postulate of weak equivalence. These
properties include an orbital velocity and an escape velocity. For a central
mass of galactic proportion, the escape velocity becomes large even at cosmological distances.
By considering the dynamics of a smaller mass occupying the last orbit, we find
that the established laws of physics lead to different rotation curves than
they do when applied to the solar system. Since galactic rotation curves reveal
the existence of dark matter, this is anticipated to have some consequences for
our understanding of dark matter.
Cite this paper
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