Did the universe exist before the Big Bang?

Concentric circles discovered in cosmic microwave background radiation (CMB) - the after-effects of the Big Bang - display evidence of events that took place before most scientists believe the universe came into being.

The controversial finding points to the existence of a universe that did not begin 13.7 billion years ago, as is generally accepted, but is instead a cycle of so-called aeons.

The discovery has been posted online by Professor Roger Penrose from Oxford University and Professor Vahe Gurzadyan from Yerevan State University, Armenia, the Daily Mail reports.

Most scientists believe the universe was created in the Big Bang around 13.7 billion years ago. Stars and galaxies started to form around 300 million years later.

Our sun was born around five billion years ago, while life first appeared on the earth around 3.7 billion years ago. The CMB dates  to 300,000 years after the Big Bang and has now cooled to around -270 degrees Celsius.

But Penrose and Gurzadyan argue that evidence unearthed by NASA's Wilkinson Microwave Anisotophy Probe in the CMB shows imprints in the radiation that are older than the Big Bang.

They say they have discovered 12 examples of concentric circles, some of which have five rings, meaning the same object has had five massive events in its history.

They believe the circles are imprints of extremely violent gravitational radiation waves generated by supermassive black hole collisions in a previous aeon before the last big bang.

Penrose believes that his new theory means that black holes will eventually consume all the matter in the universe.