  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.
