“[I]s time travel possible? Can we open a portal to the past or find a shortcut to the future? Can we ultimately use the laws of nature to become masters of time itself?”
In a recent article published by the UK’s Daily Mail, renowned theoretical physicist Stephen Hawking asks these questions and provides some startling answers. For days the internet has been abuzz about Hawking’s essay “How to Build a Time Machine,” in which the universally-recognized genius emphatically concludes that humans can accomplish time travel into the future.
For the means of voyaging through the fourth dimension, Hawking presents several possibilities: wormholes, black holes, or a VERY fast machine.
According to Hawking, physicists now believe in the existence of invisible portals through time (“wormholes”) that can facilitate fourth-dimensional travel:
“There are tiny crevices, wrinkles and voids in time. Down at the smallest of scales, smaller even than molecules, smaller than atoms, we get to a place called the quantum foam. This is where wormholes exist. Tiny tunnels or shortcuts through space and time constantly form, disappear, and reform within this quantum world. And they actually link two separate places and two different times.”
One problem, though, is their incredibly small size. But Hawking suggests that wormholes might be captured and enlarged enough for a person or a spacecraft to pass through. If so, a wormhole could take a traveler to distant planets, or to a different time on our own planet Earth.
Even with the help of wormholes, Hawking concludes that time travel to the past is impossible (thus dashing his own hopes of a tryst with a vintage-era Marilyn Monroe). This is because traveling to the past would create a paradox that the laws of nature would not permit.
The future, however, is fair game. As Hawking explains, this is partly because time moves at different speeds in different places. A massive object — such as a black hole or even our own planet Earth — can cause time to slow down dramatically. However, Hawking dismisses such natural bodies as being largely impractical time machines.
Instead he proposes a man-made alternative: a machine that can travel near the speed of light.
“It really is that simple,” Hawking claims. “If we want to travel into the future, we just need to go fast. Really fast.” But of course there’s a catch. A suitable time machine would have to be massive; and the only way it could achieve the requisite speed would be to travel through outer space. However, Hawking writes, if these conditions were met, then one could travel to the edge of the galaxy in 80 years, or approximately one lifetime.
So exploring the galaxy in one lifetime is within the realm of human potential. But I suspect that a lifetime might not be nearly enough to explore the mind of Stephen Hawking.
Don’t miss “Stephen Hawking’s Universe,” beginning May 9 on Discovery Channel at 9pm!
Stephen Hawking in zero gravity (NASA)