An Action-Reaction Interpretation of the Interaction between Cosmic Expansion and Gravitation

An updated review is presented to demonstrate the impact an expanding cosmos on three approaches to analyzing gravity. 1) the General Relativity based tensor method, 2) the Escape Velocity based conservation of energy method, and 3) the Force-Balanced based action-reaction method. The only common solution from all three methods is a flat space result with critical matter density ρ c =3H 2 /8πG where H is the Hubble parameter, and G is the gravitational constant. It is also shown that the use of a Force-Balance based analysis for action-reaction, derived from a conservation of energy baseline, is analytically equivalent to that of a General Relativity tensor-based analysis for a flat space solution. Galaxy-based energy conservation and force-balanced solutions in an expanding cosmos also indicate that cosmic expansion is the unique action-based cause of a gravitational reaction at a galaxy level. Friedmann solutions from General Relativity for open and closed space curvature, however, add a speed of light term to H that violates galaxy-based conservation of energy and action-reaction force balance requirements. Thus, such curved space solutions are not physically relevant in an expanding cosmos. Evidence from Guth-Linde Inflationary Universe models is also cited to support the validity of a unique galaxy-based flat space solution.