The Big Bang is a Coordinate Singularity for $k = -1$ Inflationary FLRW Spacetimes

TL;DR

This paper demonstrates that the big bang in certain inflationary FLRW spacetimes can be viewed as a coordinate boundary rather than a true singularity, offering new insights into cosmological models and their relation to dark energy, dark matter, and antimatter.

Contribution

It introduces a new coordinate system for Milne-like spacetimes, revealing the big bang as a coordinate boundary and generalizing previous results to a broader class of models.

Findings

The big bang is a coordinate boundary in Milne-like spacetimes.

New coordinates remove metric degeneracy at the big bang.

Insights into dark energy, dark matter, and antimatter issues.

Abstract

We show that the big bang is a coordinate singularity for a large class of $k = -1$ inflationary FLRW spacetimes which we have dubbed 'Milne-like.' By introducing a new set of coordinates, the big bang appears as a past boundary of the universe where the metric is no longer degenerate -- a result which has already been investigated in the context of vacuum decay [12]. We generalize their results and approach the problem from a more mathematical perspective. Similar to how investigating the geometrical properties of the $r = 2m$ event horizon in Schwarzschild led to a better understanding of black holes, we believe that investigating the geometrical properties of the big bang coordinate singularity for Milne-like spacetimes could lead to a better understanding of cosmology. We show how the mathematics of these spacetimes may help illuminate certain issues associated with dark energy, dark matter, and the universe's missing antimatter.