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. The current Λ− CDM model provides a stochastic fit to observations of the evolution of the universe. Methods However, a single deterministic equation can be shown to provide an excellent fit to the Λ− CDM results (Hubble Equation 24, Figure 5). The pathway to derive this equation is based on an energy/momentum (Dynamic) model of the universe in which all material is assumed to be uniformly distributed on a surface that is orthogonal to the universe’s expansion. This allows the expansion to be controlled by special rather than general relativity. Results Both the Standard Theory and the Dynamic Model, utilise the Minkowski metric, but with different coordinate systems. This paper shows that the Dynamic relativistic equations are unchanged compared to the Standard Theory for local phenomena such as the Lorentz coordinate transformation and the energy/momentum equation for high-velocity objects. Conclusions However, the Dynamic coordinates alter the perceived overall structure of the universe in a manner where, for the simplest model under this system, special relativity completely determines the universe’s expansion. This model allows the explanation 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 any additions. It also allows the production of Equation 24 which has no empirical coefficients, and which provides an excellent fit to the Λ− CDM model.