To think that our universe is 13.8 billion years old is incredible enough. But now researchers are proposing that the universe stretches back into time infinitely with no singular point where it started. The idea is one possible result of something known as ‘rainbow gravity’- a theory that is not widely accepted among physicists, though many say the idea is interesting. The theory’s name comes from a suggestion that gravity's effect on the cosmos is felt differently by varying wavelengths of light, which can be found in the colours of the rainbow. The theory was proposed 10 years ago in...