An Interpretation of Milne Cosmology

TL;DR

This paper explores how Milne's cosmological model, based solely on Special Relativity, can produce predictions similar to the standard General Relativistic model, questioning the usual interpretation of its compatibility.

Contribution

It offers a reinterpretation of Milne cosmology, suggesting that spacetime flatness due to inflation allows special relativistic predictions to align with observations.

Findings

Milne model predictions are consistent with observational data.

Spacetime flatness from inflation influences cosmological predictions.

Special Relativity can explain certain cosmological observations without General Relativity.

Abstract

The cosmological concordance model is consistent with all available observational data, including the apparent distance and redshift relationship for distant supernovae, but it is curious how the Milne cosmological model is able to make predictions that are similar to this preferred General Relativistic model. Milne's cosmological model is based solely on Special Relativity and presumes a completely incompatible redshift mechanism; how then can the predictions be even remotely close to observational data? The puzzle is usually resolved by subsuming the Milne Cosmological model into General Relativistic cosmology as the special case of an empty Universe. This explanation may have to be reassessed with the finding that spacetime is approximately flat because of inflation, whereupon the projection of cosmological events onto the observer's Minkowski spacetime must always be kinematically consistent with Special Relativity, although the specific dynamics of the underlying General Relativistic model can give rise to virtual forces in order to maintain consistency between the observation and model frames.