Is time travel possible? Yes, but you might get 'spaghettified,' says UBC astrophysicist

Have you ever wished you could turn back the clock to avoid a silly mistake? Or daydreamed about riding shotgun with Marty McFly — the character played by Michael J. Fox in the film Back to the Future — on a road trip across time?

Time travel has long captured the imagination of many. It's become the subject of countless films, novels, and scientific papers while amassing a large cult following of time-travel fanatics.

UBC astrophysicist Jaymie Matthews is one of many researchers and self-proclaimed sci-fi nerds who have plunged headfirst into the phenomena. He stopped by CBC's The Early Edition ahead of his time travel Q&A Cosmic Nights at the H.R. MacMillan Space Centre to answer one simple question: is time travel possible?

"Yes! We already know it's possible," he told host Rick Cluff. "But [driving] 88 miles an hour in a Delorian won't cut it."

Special relativity

Scientists began to confirm the possibility of time travel after Albert Einstein published his theory of special relativity. The theory illustrates that the human perception of time is an illusion. Rather than being sometime that is constant, time is relative.

The human interpretation of time actually varies depending on how fast a person is moving through space, says Matthews. And that means you could actually travel deep to the future — in theory.

"You have to travel at a speed close to the speed of light — 300,000 kilometres per second, that's more than a billion kilometres per hour. If you can get up to those kind of speeds — where you definitely don't need any roads — then your sense of time slows down compared to the place you left."

Matthews says a ten-year round trip could put you 1,000 years into the future.

But forget theories — some astronauts have already travelled time by travelling regular space speeds, like the highly popular Commander Chris Hadfield after his final mission to the International Space Station, according to Matthews.

"He turned out to be probably about a millisecond, a thousandth of a second younger."

Spaghettified

Matthews says if we travel forward in time, it might mean there's no turning back. Some physicists have tinkered with the idea of travelling back in time. But to get there, a person would have to pass through what scientists refer to as Einstein-Rosen bridge — also known as a wormhole.

By travelling through a wormhole, "there is the possibility of connecting to other dimensions in space, and perhaps earlier times in our own set of dimensions," said Matthews.

But things can get a little messy.

In theory, wormholes bend and connect different points in time and space. Most of them are created by a black hole — and moving through a black hole isn't as pretty as it appeared in Christopher Nolan's Interstellar, starring Matthew McConaughey.

"If Matthew McConaughey actually fell into a black hole through a worm hole, he would be — the technical term would be 'spaghettified' — or stretched — by the gravity.

There's no conceivable way for information to travel through a black hole, and the gravity is so strong that it would stretch whatever crossed through it.

"If you're falling into a black hole, there is no solid wall you're going to hit," Matthews said.

"If you're falling feet first, your feet are going to start falling faster than your head and eventually you might be a contender for a basketball team. Eventually, the force is going to exceed the force that holds your body together and its not going to be pretty" said Matthews.

"Matthew McConaughey is a nice -looking guy — but he would not be a nice-looking guy if he passed through a black hole."

Matthews was to appear at Cosmic Nights on Thursday, Jan. 26, dressed as Doc Brown.

With files from CBC's The Early Edition