Accounting for the expansion of the universe using an energy/momentum model to construct the space-time metric

Abstract

Background: The success of the theories of special and general relativity in describing localised phenomena, such as objects undergoing high speed motion or located in gravitational fields, needs no further elaboration. However, when applied to the evolution of the universe several problems arise which can require an additional model, e.g., inflation during the early expansion, and adjustments to parameters to account for phenomena such as the late-time acceleration of the universe. Methods: Focusing on the difference between the ways in which space and time are measured, this paper shows that there are two paths which allow the equations of special relativity to be produced from the same basic postulates. Results: While the standard theory utilises the Minkowski metric, an alternate path is possible which uses an energy/momentum, or dynamic model which transforms the Minkowski metric into an Euclidean form by multiplying the coordinates by functions of γ (=(1-v2/c2 )-1/2) to derive a new space-time metric. When utilising this dynamic metric, the relativistic equations are unchanged for local phenomena such as the Lorentz coordinate transformation and the energy/momentum equation for high-velocity objects. Conclusions: However, the derived metric alters the perceived overall structure of the universe in a manner that, for the simplest model under this system, allows the reproduction of observed cosmological features, such as the intrinsic flatness of the universe and the apparent late-time acceleration of its expansion, without the need of additional models or changes in parameter values.