Abstract
In this model gravitation results from the emission and absorption of quanta (gravitons) that are scattered a few times in crossing a typical galaxy. Many features of the universe can be explained in terms of this model, although theoretical justification for the scattering of gravitons is lacking. Gravitons follow a random walk and diffuse through the outer regions of a galaxy. As a result the force of attraction follows a 1/R law, matching observed galactic rotation curves and explaining galactic dynamics without the need of dark matter. The model makes predictions regarding early stages in the expansion of the universe and the establishment of the mass distribution. It may be assumed that a nearly uniform expanding cloud of gas was present that was subject to collapse under gravitational forces. The 1/R law of attraction due to graviton diffusion is orders of magnitude more effective for initiation of collapse than the inverse square law, and it applies to blocks of gas larger than the graviton mean free path. Delay in the spread of gravitational attraction by diffusion sets a time-dependent range beyond which the attractive force is zero. In the model this causes arrays of matter to collapse locally into zones with a spacing set by the length of the range of the attractive force. An initial examination indicates that under these conditions the background radiation could have been released from a nearly uniform distribution at the time of decoupling of radiation and matter, followed by gravitational collapse into blocks of galactic mass. In the model the diffusion of gravitons continued and collapse became possible on a larger scale, initiating the formation of galactic clusters and still larger structures. The slow rate of diffusion then prevented the largest structures from attracting each other and permitted the formation of the voids on a very large scale. The model predicts that on the largest scale there is a three-dimensional repeated array of structures separated by voids. Ultimately structures larger than galactic clusters outran the diffusion of the gravitons and have since been freely expanding.