The Motion Equations of Cosmology Need Relativity Revision

TL;DR

This paper argues that the Friedmann equations in cosmology are essentially Newtonian and proposes a revision based on proper relativistic metrics, which could alter key cosmological parameters and resolve existing puzzles.

Contribution

It introduces a new perspective that the Friedmann equations are Newtonian in essence and suggests a revised relativistic framework for cosmology.

Findings

Friedmann equations are equivalent to Newtonian gravity.

The Robertson-Walker metric is unsuitable for relativistic cosmology.

A new relativistic metric for the universe is proposed.

Abstract

The motion equation of standard cosmology, the Friedmann equation, is based on the stein's equations of gravitational fields. However, British physicist E. A. Milne pointed in 1943 that the same equation could be deduced simply based on the Newtonian theory of gravity. It means that the Friedmann equation, in stead of the motion equation of relativity, is actually the Newtonian one in essence. The reason is that two simplified conditions are used in the deduction of the Friedmann equation. One is the Robertson-Walker metric and another is static energy momentum tensor. It is proved that in light of the R-W metric, the velocity of light emitted by celestial bodies in the expansive universe would satisfy the Galileo's addition rule. So what the R-W metric describes is unsuitable to be taken as the space-time structure of relativity cosmology. On the other hand, because there are relative velocities between observer and material in the expensive universe actually, we should consider dynamic energy momentum tensor in cosmology. The Friedmann equations need relativity revision. In this way, some deductions of current cosmology, such as the values of Hubble constant, dark material and dark energy densities and so on, should be re-estimated. The possible form of relativity metric for cosmology is proposed at last. It is proved strictly based on the Einstein's equation of gravity that the space-time of the expansive universe can not be flat. In this way, by establishing cosmology on the really rational foundation of relativity, we may get rid of the current puzzle situation of cosmology thoroughly.