Wormholes: They’re not just for outer space anymore

The same mathematicians who last year introduced the world’s first “invisibility cloak” have a new show for 2007: Wormholes on Earth!


A “wormhole” is a short-cut in the fabric of space-time, a hypothetical tunnel that could carry you light-years away—or back in time. Or both. A time machine! A transporter! (You can picture a worm crawling along the surface of an apple, and suddenly realizing, hey! I can get to other side faster if I just dig a hole through the middle!)

There’s no evidence that wormholes are out there in space, just waiting to zip us away to witness the Very Beginning of Everything. And even if they are there, as Kip Thorne tells us, they’re probably not going to be able to take you back in time or let you test out the "grandfather paradox." [But wormholes are very effective for science fiction. In Carl Sagan’s Contact, the main character, Eleanor Arroway (played by Jodie Foster in the 1997 film) travels through space via a series of wormholes.]

Here on Earth, some mathematicians are claiming that it might be possible to build one in a lab. Allan Greanleaf, a mathematician at the University of Rochester, made headlines last year with his invisibility cloaking device, which diverts electromagnetic radiation and becomes undetectable. Now, Greenleaf says he can use the same technology to shield a small tunnel from electromagnetic detection. Objects go in one side, disappear, and come out the other.

[All right, all right. It’s not exactly the same. It just looks like a wormhole. A wormhole is not just an invisible tunnel in spactime; it is a tunnel that cuts through space-time. ]

And what if you looked through Greenleaf’s wormhole?

Assuming that your vision was limited to the few frequencies at which the wormhole operates, looking in one end, you'd see a distorted view out the other end, according the simulations by Greenleaf and his coauthors. Depending on the length of the tube and how often the light bounced around inside, you might see just a fisheye view out the other end, or you might see an Escher-like jumble.