The Big Bang might have been just a Big Bounce
http://phys.org/news/2016-07-big.html
A new study of the early universe reveals how it could have been formed from an older collapsing universe, rather than being brand new.
The universe is currently expanding and it is a common theory that this is the result of the 'Big Bang' – the universe bursting into
existence from a point of infinitely dense and hot material.
However, physicists have long debated this idea as it means the universe began in a state of complete breakdown of physics as we know it.
Instead, some have suggested that the universe has alternated between periods of expansion and contraction, and the current expansion is
just one phase of this.
This so-called 'Big Bounce' idea has been around since 1922, but has been held back by an inability to explain how the universe transitions
from a contracting to an expanding state, and vice versa, without leading to an infinite point.
Now, in a new study published today in Physical Review Letters, Dr Steffen Gielen from Imperial College London and Dr Neil Turok, Director
of the Perimeter Institute for Theoretical Physics in Canada, have shown how the Big Bounce might be possible.