Ring-like patterns in the sky could be ghostly imprints of a universe that existed before the big bang, according to a controversial new study.
If the theory is correct, the cosmic rings may be the first real-world evidence that our current universe is just the latest in an endless string of recycled universes, the study authors say.
Astronomers found the circular patterns in a new analysis of the cosmic microwave background (CMB), which is the radiation left over from the big bang that now permeates the universe.
Within the newly described rings, many of which are nested like ripples in a pond, the temperature is more uniform than elsewhere in the CMB sky.
One possible explanation for these rings is that they were created when black holes collided in a previous universe, according to Roger Penrose of the University of Oxford in the U.K. and Vahe Gurzadyan of the Yerevan Physics Institute in Armenia.