One possible interaction-inertial interaction
  Proposed in this paper is a possible interaction which exists in nature - inertial interaction. It gives matter an inertia and inertial mass. The formula of inertial mass has been derived. It is possible that inertial interaction leads to the redshifts of quasars, the rotation curve of spiral galaxy, the accelerating expansion of the universe, and the stronger gravitational lens effects of quasars, galaxies, or clusters of galaxies. Einstein's Gravitational Equation has been modified. Gravitational redshift, perihelion precession, and bending of light in spherically symmetric vacuum gravitational field are calculated. The differential equations of static spherically symmetric star's internal evolution are given. The accelerating expansion stage of the universe evolution equations are derived. The evolution of the universe is periodic. Time does not have an origin. There is no Big Bang. Although there is divergent singularity, there is no universe's singularity of incomplete geodesic. There are no horizon problem and no flatness problem. The problems that may exist are discussed. 
Xuejun Yang
physics.gen-ph gr-qc