Each possibility is a reality in a different world. . . In that parallel universe where granddad never made it to first grade or ran off with the circus, you were not born. But there are other granddad universes and therefore other ways to make you.
Fred Alan Wolf Parallel Universes
Time present and time past
Are both perhaps present in time future,
And time future contained in time past.
T.S. Elliot Burnt Norton