How did the univrse begin?
The most popular scientific theory 
today is that the universe
came into existence around 13.7 billion 
years ago in an event known as the Big Bang
But how and why did this event take place
and did anything exist before it?
The Big Bang theory states that originally 
all matter and energy
of the known universe was contained in a tiny point
The point was so hot and dense that all 
the basic forces of nature were unified
and indistinguishable from one another
The Universe was then at its Primordial Stage
For unknown reasons the universe then 
suddenly expanded and cooled down
The Strong nuclear force and 
the electroweak force separated
unleashing a tremendous amount of stored energy
The universe grew exponentially - doubling its size 90 times in an incredibly short period of time
a hundredth of a billionth of a trillionth of a trillionth 
of a second to be precise
This incredible growth spurt is called 
the Singularity Expansion
From here the building blocks of
our known universe were created
from particles, atoms, elements 
to eventually stars and galaxies
That explains how the universe came into existence
Working out what came before it is a lot tricker
One theory is there was nothing 
at all before the Big Bang
the universe materialized out of nothing
As Stephen Hawking explained, the universe  “would be neither created nor destroyed. It would just BE.”
But another idea is that there 
was a universe before this one
The “Two-Headed Time” theory suggests
that time effectively moved backwards for
billions of years as the universe contracted
finally reaching subatomic size
The Big Bang then happened, reversing the process as the universe expanded out to what we see today
with the universe being born again and again and again, the process would be cyclical
Others have suggested that our universe could 
be the offspring of another universe
or just one of many universes that 
were formed out of the Big Bang
Unfortunately we cannot definitively 
answer this question, only speculate
Hopefully one day, we can figure out exactly 
how the universe came into existence
and if there was anything before it
