London: Our universe may have ‘bounced’ into existence from an older collapsing one, rather than expanding from a single point of dense, hot material, according to new study that provides support to the ‘Big Bounce’ theory to explain the birth of our cosmos, reports PTI.
The universe is currently expanding and it is believed to have burst into existence from a point of infinitely dense and hot material, an event dubbed as the Big Bang. 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.
In a new study, Steffen Gielen from Imperial College London and Neil Turok, Director of the Perimeter Institute for Theoretical Physics in Canada, have shown how the Big Bounce might be possible.
Observations suggest that during its very early life, the universe may have looked the same at all scales – that is the physical laws that worked for the whole the universe also worked at the scale of the very small, smaller than individual atoms. This phenomenon is known as conformal symmetry. In the present-day universe, this is not the case – particles smaller than atoms behave very differently to larger matter and the symmetry is broken.