Get Ready for Time Travel-- Stephen Hawking

Well, not exactly. But he does have an interesting set of hypotheses regarding the concept. In fact, he has three ideas.

"Imagine that the train left the station on January 1, 2050. It circles Earth over and over again for 100 years before finally coming to a halt on New Year's Day, 2150. The passengers will have only lived one week because time is slowed down that much inside the train. When they got out they'd find a very different world from the one they'd left. In one week they'd have travelled 100 years into the future," Hawking writes.

Right now, the fastest motion on Earth is taking place in the circular tunnels of the world's largest particle accelerator at CERN, in Geneva.

"When the power is turned on (particles) accelerate from zero to 60,000 mph in a fraction of a second. Increase the power and the particles go faster and faster, until they're whizzing around the tunnel 11,000 times a second, which is almost the speed of light. But just like the train, they never quite reach that ultimate speed. They can only get to 99.99 per cent of the limit. When that happens, they too start to travel in time. We know this because of some extremely short-lived particles, called pimesons. Ordinarily, they disintegrate after just 25 billionths of a second. But when they are accelerated to near-light speed they last 30 times longer."