The Four Space-times Model of Reality
  We live in a 3+1 space-time that is intended as a description of the universe with three space dimensions and one time dimension. Space-time dimensionality seems so natural that it is rarely criticized. Experiments and the highly successful relativistic theories teach us that there are four fundamental dimensions, among them is time that is treated as a special dimension. The specialty of time can be removed, leading to the concept that time is simply a function of four new fundamental dimensions, which have now identical properties, in combination with Lorentz invariance. A model is deduced in which a 4-space, characterized by four space-like coordinates, may host four "equivalent but orthogonal" space-times, each with three spatial coordinates and one temporal coordinate. Coordinates are shared; therefore the 4-space and the four space-times are all in one. Electromagnetic interaction is confined in each space-time and the role of the speed of light appears to be that of a barrier for the electromagnetic interaction. The motion of objects can be described by four-dimensional optics in the 4-space. Each of the four space-times may host a universe and, in agreement with recent observations, the proposed model can be directly applied to problems like the cosmological matter-antimatter asymmetry and dark-matter issues. Space travel may also benefit from the concepts presented. 
Giorgio Fontana