All the Myriad Ways
by Larry Niven
Detective-Lieutenant Gene Trimble suspects that the recent spate of suicides and violent
crime is somehow connected to the discovery that the many worlds
interpretation of quantum physics is real and each of those worlds can be traveled
to.
— Michael Main
There were timelines branching and branching, a mega-universe of universes, millions more
every minute. Billions? Trillions? Trimble didn’t understand the theory, though God
knows he’d tried. The universe split every time someone made a decision. Split, so that
every decision every made could go both ways. Every choice ever made by every man, woman
and child on Earth was reversed in the universe next door.
“All the Myriad Ways” by Larry Niven, in Galaxy,
October 1968.