So you could, in a way... live both lives

Noah to Alison:

There's this hypothesis in theoretical physics that I used to love back at school, about time travel. About what would happen if you could travel back in time and make a different choice in your past, how that would affect your life in the future.
So the theory goes that, um, your true life, your first life, continues as is, unchanged, but at the moment of decision, a new life splits off along a tangent into a parallel universe.

The Affair
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