In the dimension of space, you can move forwards and backwards, but time is different. Time is irreversible.
The Big Bang theory claims the universe, and time, had a beginning but physicists are divided about whether it will end, and more importantly, how.
Theories range from the decay of dark matter to a Big Rip and in an article for The Conversation, astrophysicist Thomas Kitching has explained how this could work.
He also details why time is forever marching forward and what the expansion of the universe means for humanity.
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