Meditações - uma série infinita de tempos

Alternate lives playing out over different dimensions are another important offshoot of time travel. Perhaps our universe—like Coop’s timeline—is merely one among many. Perhaps you could even hop from one to another.

If you look up multiverse in the Oxford English Dictionary, you learn that it was “orig. Science Fiction”—and now it’s Physics, too: a putative ensemble of many universes, of which our own little home is merely one. The great Argentine writer/philosopher Jorge Luis Borges offered his conception in a 1941 short story, “The Garden of Forking Paths”: Rather than unidirectional Newtonian time, he proposes “an infinite series of times, in a growing, dizzying net of divergent, convergent and parallel times…times which approached one another, forked, broke off, or were unaware of one another.”

That wasn’t science to Borges, but it became science 15 years later. A physics graduate student named Hugh Everett, trying to resolve the quantum puzzle that causes Schrödinger’s cat to be both alive and dead, proposed that every quantum measurement is a branching of the entire universe. In one fork the cat is alive; alas, it is dead in another. This is now known as the many worlds interpretation of quantum mechanics. As the theorist David Deutsch explains, “Time does not flow. Other times are just special cases of other universes.”

We’re surprisingly comfortable with this idea of multiple lives being played out simultaneously in multiple realms. In his 2014 novel The Peripheral, William Gibson calls his time-branches “stubs.” Parallel universes drive the 1998 movie Sliding Doors, in which a Londoner played by Gwyneth Paltrow slips back and forth between two timelines, one happy and one sad. (The portal between universes seems to be a train on the Tube.) Star Trek and Doctor Who have explored parallel universes; Donnie Darko is another parallel-universe time-travel movie; and so is, when you think about it, the James Stewart classic It’s a Wonderful Life.

So sure, it could be science. Or it could be mumbo-jumbo. Remember what young Murph says: Science is about admitting what you don’t know.

James Gleick in Quartz, sobre O Jardim dos Caminhos que se Bifurcam, de Jorge Luís Borges e outras ficções sobre tempor diferentes em universos paralelos