From our perspective, time is always moving forward, but according to some theoretical research, it might be possible that the Big Bang also created a mirrored universe where time moves backwards relative to our own understanding.
Researchers refer to the movement of time as an arrow, because in the known universe it is moving constantly in one direction.
After the Big Bang, it is believed universe started cooling down and expanding to form stars, planets and other celestial bodies, and the arrow of time followed the same direction as increasing entropy, or the progression from order to disorder.
According to a new theory proposed by Julian Barbour, visiting Professor in Physics at the University of Oxford, expansion of the universe didn’t just happen in one direction, but two opposite directions. This allows for the possibility of a mirrored universe where time moves backwards compared to our own universe.
Barbour explains the findings by saying: “If they were complicated enough, both sides could sustain observers who would perceive time going in opposite directions. Any intelligent beings there would define their arrow of time as moving away from this central state.”
Barbour and his colleagues believe gravity is responsible and tested their theory using a model of one thousand particles based on Newton’s physics.
Their system showed that the force of gravity influenced the universe’s expansion and time direction without needing a ‘low entropy initial condition’.