Star Trek-style cloaking device comes a step nearer
A Star Trek-style device that allows people to disappear and then – in a blink of an eye – reappear in a different location is a step closer to reality, claim British scientists.
The physicists claim they have proved that it is possible to manipulate space and time so that whole events are hidden from view.
That means eventually that someone could be made to look like they jump from one location to the next – with the journey in-between rendered invisible to the naked eye.
The "space time cloak" uses physics to manipulate light so that "events" in real life are cut just like an editor can cut scenes from a reel of film.
The device sounds like the stuff of fantasy, but scientists at Imperial College London have proved it could work in theory – at least in terms of very short bursts of time.
As well as being a sci-fi fan's dream, they believe the idea could also be used to make faster and more powerful computers.
Professor Martin McCall, the lead scientist, said that the technique worked by dividing up rays of light that are heading towards the eye.
By speeding up the front part of the ray and then slowing down the rear, you can create a gap which could be filled with an event or action.
Then by reversing the speeds the gap could be closed again before the light reaches the observer making it look nothing has happened.
At the moment it should be possible to cut two thousandth of a millionth of second from time but in future seconds or even minutes could be cut.
"Imagine a camera that is on a time delay watching a safe," said Prof McCall. "If a thief opens the safe, steals the money and locks it again in between the pictures being taken it will appear as if nothing has happened.
"We have shown that by manipulating the way the light illuminating an event reaches the viewer, it is possible to hide the passage of time in the same way.
"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.
"So, theoretically, this person might be able to do something and you wouldn't notice."
In previous experiments to create "invisibility cloaks" scientists have shown that light can be curled around objects to make them seem invisible.
The teleporters used in Star Trek are said to have been based on the idea of "quantum entanglement" in an object or person is broken down into photons of light or atoms, transported and then re-materialised in a different place.
This new technology would not actually transport anyone just hide their journey.
Researcher Alberto Favaro said: "It is unlike ordinary cloaking devices because it does not attempt to divert light around an object.
"Imagine computer data moving down a channel to be like a highway full of cars.
"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."
In order to create a gap of time of about two thousandth of a millionth of a second researchers reckon they need almost two miles of fibre optic cable wrapped around a spool.
With current technology to hide a second of time would require more than 200 million miles but eventually if light could be slowed down then longer periods could be possible.
The research is outlined in the Institute of Physics' Journal of Optics.