"It's actually a famous solution to the Einstein field equations of general relativity," says Max Tegmark, a cosmologist at the Massachusetts Institute of Technology in Boston. "The idea is you have these two black holes connected together by a wormhole. You jump into one of these black holes, and you come out of a 'white hole' somewhere else at the same time."
The problem with wormholes? "We know that they don't exist," says Lawrence Krauss, an astrophysicist at Case Western Reserve University in Cleveland and the author of The Physics of Star Trek. "The mouth of the wormhole would actually collapse to a black hole, and you'd never be able to get out of the mouth."
Wormholes could exist, he says, only "if you had what's called negative energy to keep the mouth open, and we know that no normal matter does that."
'These awful laws of physics' slow us down
Says Tegmark: "Most people do think that wormholes are unstable, but nobody has managed to prove rigorously that you can't somehow stabilize them with some weird kind of dark energy. So we're still in this tantalizing situation where we're assuming it's impossible, but if you push it, we can't prove it.
"My guess is that it's probably impossible, but the jury is still out."
As for the appeal of teleporting, Krauss says that at least is straightforward: "People yearn," he says. "We're trapped by these awful laws of physics that tell us we can't get anywhere we want to get immediately." Teleporting, he says, would give us a taste of freedom not usually allowed in the physical world — kind of like the movies themselves.