The model generally referred in the OP, can be more correctly be called the "Hot BB model"
https://faraday.physics.utoronto.ca/PVB/Harrison/GenRel/BigBangModel.html
https://en.wikipedia.org/wiki/Big_Bang
But there was also a version, ironically first modelled by the Father of the BB, George LaMaitre....this was known as the Cold BB model.
Details on that follow.........................
https://en.wikipedia.org/wiki/Cold_Big_Bang
Cold Big Bang is a designation used in
cosmology to denote an
absolute zero temperature at the beginning of the Universe, instead of a (hot)
Big Bang.
In an attempt to understand the origin of
atoms,
Georges Lemaître proposed (by 1927) that before the
expansion of the universe started all the
matter in the
universe, it formed a gigantic ball of nuclear liquid at
very low temperature. This low temperature was required to provide an adequate
cohesion within the
Lemaître's primeval atom. In 1966,
David Layzer proposed a variant on Lemaître's cosmology in which the initial
state of the universe was near
absolute zero. Layzer argued that, rather than in an initial high
entropy state, the
primordial universe was in a very low entropy state near absolute zero.
The mainstream version of the Cold Big Bang model predicted an absence of
acoustic peaks in the
cosmic microwave background radiation
[1] and was eventually explicitly ruled out by
WMAP observations.
You sound angry river? The proof is obvious to all, unless you are just trolling? Are you trolling river?
The point is the BB theory is overwhelmingly supported and aligns with the four observational cosmological pillars. Glad you finally accept that. But references are available if you need one?