UK Mathematicians Claim "Cloaking" Is Possible

[Mr. Chronopoulos]

'Cloaking device' idea proposed

The work brings science fiction closer to science fact - just a little

The cloaking devices that are used to render spacecraft invisible in Star Trek might just work in reality, two mathematicians have claimed.

They have outlined their concept in a research paper published in one of the UK Royal Society's scientific journals.

Nicolae Nicorovici and Graeme Milton propose that placing certain objects close to a material called a superlens could make them appear to vanish.

It would rely on an effect known as "anomalous localised resonance".

If the speck of dust is close enough it induces a very aggressive response in the cloaking material

Professor Sir John Pendry, Imperial College London

However, the authors have so far only done the maths to verify that the concept could work. Building such a device would undoubtedly pose a significant challenge.

Starting small

Cloaking devices are a form of stealth technology much favoured by Star Trek baddies such as the Romulans and Klingons.

The complex mathematical phenomenon outlined by Milton and Nicorovici closes the gap a little between science fiction and fact.

The phenomenon is analogous to a tuning fork (which rings with a single sound frequency) being placed next to a wine glass. The wine glass will start to ring with the same frequency; it resonates.

The cloaking effect would exploit a resonance with light waves rather than sound waves.

The concept is at such a primitive stage that the scientists talk only at the moment of being able to cloak particles of dust - not spaceships.

In this example, an illuminated speck of dust would scatter light at frequencies that induce a strong, finely tuned resonance in a cloaking material placed very close by.

The resonance effectively cancels out the light bouncing off the speck of dust, rendering the dust particle invisible.

One way to construct a cloaking device is to use a superlens, made of recently discovered materials that force light to behave in unusual ways.

Vanishing point

Professor Sir John Pendry, of Imperial College London, who helped pioneer superlenses, said: "If the speck of dust is close enough it induces a very aggressive response in the cloaking material which essentially acts back on the speck of dust and forces it to stop shining.

"Even though light is hitting the speck of dust, scattering of the light is prevented by the cloak which is in close proximity," he told the BBC News website.

The authors of the paper argue that the cloak needn't just work with a speck of dust, but could also apply to larger objects.

But they admit the cloaking effect works only at certain frequencies of light, so that some objects placed near the cloak might only partially disappear.

"I believe their claims about the speck of dust and a certain class of objects. In the paper, they do give an instance about a particular shape of material they can't cloak. So they can't cloak everything," said Professor Pendry.

"Nevertheless, it's a very neat idea to get this aggressive response from the material to stop tiny things emitting light."

The Imperial College physicist agreed this particular concept had potential military uses: "Providing the specks of dust are within the cloaked area, the effect will happen. A cloak that only fits one particular set of circumstances is very restrictive - you can't redesign the furniture without redesigning the cloak."

Details are published in Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

http://news.bbc.co.uk/2/hi/science/nature/4968338.stm

Edited May 28, 2006 by fred666

[sundayx Veteran]

relevant news: http://www.engadget.com/2006/05/02/japanes...arent-material/

[Fred Derf Veteran]

[Thread Moved from NFN to SS]

[crimsonhead]

Noise canceling headphones... Light canceling spaceship...

[The_Decryptor Veteran]

Now, i might be wrong, but wouldn't the cloaked object just be a dark mass, void of light?

Because, how does this material transport light around the object (to show what's behind the object to the observer)?

[SoCalledChaos]

it would be like inverted mirrors.. instead of seeing directly in the opposite direction, its getting the information from the other side? I dunno just a guess

[SaLiVa]

I can imagine the army (Be it US or UK) tripping over each other giving this guy a hell of allota funding to get this researched and confidentialized.

[Hum]

Sounds cool -- but not much use except for Military purposes. And I don't think it would be long before someone would find a counter-measure to 'cloaking'. :shiftyninja:

[comk]

Now, i might be wrong, but wouldn't the cloaked object just be a dark mass, void of light?

Because, how does this material transport light around the object (to show what's behind the object to the observer)?

it can be done..just imagine there are millions of tiny reflective mirrors

[Fred Derf Veteran]

Just tape that to your spaceship!

[davemania]

it can be done..just imagine there are millions of tiny reflective mirrors

I don't unserstand how the image demonstrates that the these mirrors can reflect the background of that obejct to the viewer ?

[Fred Derf Veteran]

I don't unserstand how the image demonstrates that the these mirrors can reflect the background of that obejct to the viewer ?

The pink bug would appear to see through the red bug and instead see the blue bug on the other side.

Likewise, the blue bug would see through the red bug and see the pink bug on the other side.

[davemania]

The pink bug would appear to see through the red bug and instead see the blue bug on the other side.

Likewise, the blue bug would see through the red bug and see the pink bug on the other side.

Ahhh I see, couldn't make sense of the German.

[El Bourricot]

I can imagine the army (Be it US or UK) tripping over each other giving this guy a hell of allota funding to get this researched and confidentialized.

There already are devices like that. For example there's clothing designed, like in Predator the movie, to "blend" colour with the surroundings. Not quite the Predator's bending of light rays around himself, but more akin to a chameleon.

Obviously it's still very impractical. The reason this kind of stuff most probably won't make it to basic Army soldiers is that the disadvantages far outweigh the possible advantages. It takes one guy with infrared lenses to detect the guy in his expensive clothing, and shoot right through that expensive suit.

It's the same reason Army folks are issued with light body armour, which stops debris etc. from entering the body but are useless against rifle bullets and similar bigger things - a fully comprehensive armour like those used by demining teams would be highly impractical for a soldier who has to run, and it's much more efficient to tell the soldier to avoid the bullets.

[The_Decryptor Veteran]

it can be done..just imagine there are millions of tiny reflective mirrors [img.]http://upload.wikimedia.org/wikipedia/commons/thumb/c/c0/UNSIBA-5_Unsichtbarkeit_mit_Spiegeln.jpg/684px-UNSIBA-5_Unsichtbarkeit_mit_Spiegeln.jpg[/.img]

The thing is, that really doesn't match the situation this "cloaking" device would make.

For once, that involves 3 mirrors, and hiding a object under a mirrored slope, but if you made a suit of hundred of tiny mirrors, it would reflect light back at the viewer, not around it, e.g. like a mirrored tube.

[Trix.Neo]

It's the same reason Army folks are issued with light body armour, which stops debris etc. from entering the body but are useless against rifle bullets and similar bigger things - a fully comprehensive armour like those used by demining teams would be highly impractical for a soldier who has to run, and it's much more efficient to tell the soldier to avoid the bullets.

That made me chuckle, regardless of what ya waering wouldn't you rather avoid it? ;)

[p858snake]

Sounds cool -- but not much use except for Military purposes. And I don't think it would be long before someone would find a counter-measure to 'cloaking'. :shiftyninja:

In theroy if you chuck another solid object (paint,mud,flour) it should stick to the invisible object(which is still a solid object as well) causing you to be able to see the solid object.

[MGS4-SS]

Sounds cool -- but not much use except for Military purposes. And I don't think it would be long before someone would find a counter-measure to 'cloaking'. :shiftyninja:

Thermal googles.

[primexx]

much more efficient to have small cameras project images to the opposit side....i believe it's being done right now?

[nomis_nehc]

That made me chuckle, regardless of what ya waering wouldn't you rather avoid it? ;)

i had the same response but i add: it's a lot easier to tell them to dodge it instead of actually dodging it (duh).

[comk]

The thing is, that really doesn't match the situation this "cloaking" device would make.

For once, that involves 3 mirrors, and hiding a object under a mirrored slope, but if you made a suit of hundred of tiny mirrors, it would reflect light back at the viewer, not around it, e.g. like a mirrored tube.

yeah, that's what I was thinking too but nevertheless it's still a good concept.

[Osiris]

It seems every couple of months new theories and developments in invisibility based physics and science appear on the news headlines. Once the stuff of science fiction, the constant developments may suggest unless the technology is suppressed or stiffled by Militarization, we may yet see the stuff of science fiction, in our lifetimes:

Boffins bend light

From: Reuters By Maggie Fox in Washington

May 26, 2006

NEW materials that can change the way light and other forms of radiation bend around an object may provide a way to make objects invisible.

Two separate teams of researchers have come up with theories on ways to use experimental "metamaterials" to cloak an object and hide it from visible light, infrared light, microwaves and perhaps even sonar probes.

Their work suggests science-fiction portrayals of invisibility, such as the cloaking devices used to hide space ships in Star Trek, might be truly possible.

Full Story

[Rob2687]

Here's another article dealing with this cloaking stuff.

http://www.ctv.ca/servlet/ArticleNews/stor...60525/20060525/

[Jaded]

Sounds interesting. But for sure this will be classified as whatever is above ultra top top secret by the military and used for stealth technology. Also since this would be at the sub-atomic level, and not something you can turn on or off, I am wondering how you would be able to find the plane, tank, ship, etc after you left it if you cant see it.

[Fred Derf Veteran]

Scientists work up a disappearing act

ANNE MCILROY

SCIENCE REPORTER

The invisibility cloak that allowed Harry Potter to wander unseen through the halls of Hogwarts is no longer confined to the realm of fiction.

Researchers in Britain and the United States have published a theoretical blueprint for constructing an invisibility cloak using revolutionary new materials engineered to bend light and other electromagnetic waves in ways not seen in nature.

Sir John Pendry, a theoretical physicist at Imperial College London, says he may be able to make himself disappear in five years.

"Maybe I'm being optimistic," he says, "but I think it could happen."

It sounds like magic, but involves what are known as metamaterials, invented by Muggles (as non-wizarding folk are called in J.K. Rowling's books).

Metamaterials are engineered to include tiny physical structures -- metal coils, or rods shaped like aerials. Scientists have been able to "tune" these materials to bend electromagnetic waves in strange ways.

The plan, according to Sir John and his colleagues, is to channel light or other electromagnetic waves around an object, then restore them to their original trajectory on the other side.

"The cloak would act like you've opened up a hole in space," says David Smith, a professor of electrical and computer engineering at Duke University in North Carolina. He and Sir John co-authored a paper on cloaking devices published in this week's on-line edition of the journal Science.

Hide an object in a metamaterial cloak, Dr. Smith says, and electromagnetic waves would flow around it as water flows virtually undisturbed around a smooth rock.

The work is most advanced in channelling the radio waves used in radar, and researchers say they may be able to hide planes or ships from enemy radar systems. The military applications are important, and in the United States the work is funded in part by the Defence Advanced Research Projects Agency, which is responsible for developing new technology for the Department of Defence.

Dr. Smith is probably about 18 months away from developing a radar cloaking device using metamaterials, Sir John says.

But even more astounding -- at least for the average person -- is the idea of wrapping yourself in an invisibility cloak and disappearing.

Bending visible light is more difficult, the researchers say, because it has a much shorter wavelength than radio waves. This means the rods and coils would have to be extremely small, and perhaps built atom by atom with nanotechnology.

Is it doable? University of Toronto researcher George Eleftheriades thinks so. He designs metamaterials. "Something will come eventually, in a couple of years. It is not easy, but it is not impossible. And people are pretty smart when the stakes are high."

He described the blueprint published by Sir John and his colleagues as "very exciting, very ingenious work."

But it is not quite a match for the imagination of Ms. Rowling. In her books, Harry Potter's cloak is so thin, it fits in the inside pocket of his jacket. The real-life version would probably be quite a bit bulkier, Sir John says.

"We can't do gossamer thin," he says.

In the novels, Harry can see his silvery cloak, which he inherited from his father. But you wouldn't be able to see one made out of a metamaterial, Sir John says.

The young wizard can also see where he is going while wearing the cloak; that wouldn't be possible in the real-life version, Dr. Eleftheriades says.

Sir John and Dr. Smith first demonstrated metamaterials in 2000, and as many as three other teams are now researching how they could be used to make someone or something invisible. Another researcher, Ulf Leonhardt of the University of St. Andrews in Scotland, independently put forward a similar plan for an invisibility cloak, which was also published yesterday by the journal Science.

http://www.theglobeandmail.com/servlet/sto...Technology/home