As the research attests, the early universe was so uniform that time looks symmetric going backwards and forwards.
The paper argues that the way we understand the world and wider universe around us, moving forwards in time, must also be expanded to include a mirrored version which runs backwards in time.
Could there really be a 'backwards' universe?Creative Commons
It could also provide a deeper understanding of dark matter, too. The theory suggests that it is an invisible particle which only interacts via gravity and provides a pairing to the electron-neutrino, muon-neutrino and tau-neutrino.
The research suggests that the conditions in a mirrored universe where time runs backwards would be full of these paired neutrinos, which would account for dark matter.
Of course, we’d never be able to experience time running backwards even if it did definitely exist, but it’s a pretty cool theory none-the-less.