Original URL: http://www.theregister.co.uk/2010/11/16/spacetime_cloak/

'Spacetime cloak' could act as 'Star Trek transporter'

Hey boffins: You do the science, we write the headlines, OK?

By Lewis Page

Posted in Science, 16th November 2010 11:48 GMT

Top boffins at Imperial College in London, an institution famed for its pioneering research into invisible sheds, have outdone themselves this time. They say they have applied the undetectable garden sanctum theory of metamaterials to produce a still cunninger concept - a type of "space-time cloak" which would produce the "illusion of a Star Trek transporter".

Professor Martin McCall, leading the team of spacetime-furtlers, explains how the new idea works.

"Light normally slows down as it enters a material, but it is theoretically possible to manipulate the light rays so that some parts speed up and others slow down," says the prof.

This would mean that downstream of the metamaterial there would be an interruption in beams of photons travelling through space - creating a "corridor" in which "energy, information or matter can be transported undetected".

"If you had someone moving along the corridor, it would appear to a distant observer as if they had relocated instantaneously, creating the illusion of a Star-Trek transporter," says McCall. "So, theoretically, this person might be able to do something and you wouldn't notice!"

We here on the Reg boffinry hyperbole desk call foul on this, frankly. No one likes to baselessly claim Star Trek effects for new scientific breakthroughs more than us, but this is into the realm of naughtiness.

A Star Trek transporter, as any fule kno, is not employed for the purpose of allowing people or stuff to zip undetected across someone's line of vision. Rather it moves people between a starship in orbit and planetary surfaces, miraculously imparting or removing large velocities in the process so that they aren't smeared all over the landscape or transporter bay on arrival*.

Then, again, this is not a cloak. As Professor John Pendry (also of Imperial, and a major metamaterials boffin) has excellently commented regarding visible-light metamaterials:

"This isn't anything that flaps around in the breeze; it's more like a shed."

Or in this case a highly specialised piece of seemingly transparent garden siding, behind which someone with impeccable timing and able to run at a significant fraction of the speed of light might in implausible circumstances be able to move along without you noticing - seeming to vanish and then reappear at the other end.

But to be fair the boffins are only playing we media scumbags at our own game with all the Star Trek and invisibility cloak gumble. In fact the new science is for real, and could well have serious application in the near future.

In particular you might be able to do some interesting things with optical signals using metamaterial-based processors, for which McCall and his team already have a proof-of-concept design.

According to a statement from Imperial:

A given data channel could for example be interrupted to perform a priority calculation on a parallel channel during the cloak operation. Afterwards, it would appear to external parts of the circuit as though the original channel had processed information continuously, so as to achieve 'interrupt-without-interrupt'.
Animation illustrating 'spacetime cloak' concept. Credit: Imperial College

Piercing the spacetime cloak through the magic of animation.

"Imagine computer data moving down a channel to be like a highway full of cars," says Alberto Favaro, one of the boffins who worked on the plan (see the animation). "You want to have a pedestrian crossing without interrupting the traffic, so you slow down the cars that haven't reached the crossing, while the cars that are at or beyond the crossing get sped up, which creates a gap in the middle for the pedestrian to cross. Meanwhile an observer down the road would only see a steady stream of traffic."

The paper describing the work, A spacetime cloak, or a history editor, is published in the Journal of Optics. It can be read here (free signup for the next 30 days, thereafter subscription required). ®

Bootnote

*And incidentally making the transitions between ship interiors and planet scenes extremely cheap to stage. A thought which never crossed Gene Roddenberry's mind, of course.