Novelists and screenwriters know that time travel can be accomplished in all sorts of ways: a supercharged DeLorean, Hermione’s small watch and, most recently, a spacetime-bending hot tub have allowed fictional heroes to jump between past and future.
But physicists know that time travel is more than just a compelling plot device — it’s a serious prediction of Einstein’s general relativity equations. In a new study posted online July 15, researchers led by Seth Lloyd at MIT analyze how some of the quirks and peculiarities of real-life time travel might play out. This particular kind of time travel evades some of its most paradoxical predictions, Lloyd says.
Any theory of time travel has to confront the devastating ‘grandfather paradox,’ in which a traveler jumps back in time and kills his grandfather, which prevents his own existence, which then prevents the murder in the first place, and so on.
I certainly don’t have the physics background to understand the scientific concept of time travel, but I’ve always found the possibility to be a fascinating literary device. Here’s a bit of the scientific perspective.