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For all you Harry Potter fans who have always wished to have an invisible cloak of your own, your wait just might be over, thanks to the infamous US military funding agency known as DARPA.

According to an on-line only publication in the highly reputable scientific journal Science (the premier scientific publication in the US), it would appear that the physics of invisibility, at least at the theoretical and technical levels, has been established. More below the jump, or check out snippets here yourself

Note: this article is online-only because the print edition has already been sent out, and this is a routine process for high-impact articles that have already been accepted for publication but whose dissemination shouldn't be delayed until the paper edition leaves the printshop.

There are two articles that discuss the findings, and so far I can only excerpt the first few sentences of each.

Controlling Electromagnetic Fields
J. B. Pendry 1*, D. Schurig 2, D. R. Smith 2

1 Department of Physics, Blackett Laboratory, Imperial College London, London SW7 2AZ, UK.
2 Department of Electrical and Computer Engineering, Duke University, Box 90291, Durham, NC 27708, USA.

* To whom correspondence should be addressed.
J. B. Pendry , E-mail:

Using the freedom of design that metamaterials provide, we show how electromagnetic fields can be redirected at will and propose a design strategy. The conserved fields--electric displacement field D, magnetic induction field B, and Poynting vector S--are all displaced in a consistent manner. A simple illustration is given of the cloaking of a proscribed volume of space to exclude completely all electromagnetic fields. Our work has relevance to exotic lens design and to the cloaking of objects from electromagnetic fields.

Optical Conformal Mapping
Ulf Leonhardt 1*

1 School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS, Scotland.

* To whom correspondence should be addressed.
Ulf Leonhardt , E-mail:

An invisibility device should guide light around an object as if nothing were there, regardless of where the light comes from. Ideal invisibility devices are impossible due to the wave nature of light. This paper develops a general recipe for the design of media that create perfect invisibility within the accuracy of geometrical optics. The imperfections of invisibility can be made arbitrarily small to hide objects that are much larger than the wavelength. Using modern metamaterials, practical demonstrations of such devices may be possible. The method developed here can be also applied to escape detection by other electromagnetic waves or sound.

As for a lay summary, here's all I feel comfortable quoting while still respecting the copyright:

News of the Week
High-Tech Materials Could Render Objects Invisible
Adrian Cho

No, this isn't the 1 April issue of Science, and yes, you read the headline correctly. Materials already being developed could funnel light and electromagnetic radiation around any object and render it invisible, theoretical physicists predict online in Science this week ( and In the near future, such cloaking devices might shield sensitive equipment from disruptive radio waves or electric and magnetic fields. Cloaks that hide objects from prying eyes might not be much further off, researchers say.

The papers are "visionary," says George Eleftheriades, an electrical engineer at the University of Toronto in Canada. "It's pioneering work that sets the stage for future research." Greg Gbur, a theoretical physicist at the University of North Carolina, Charlotte, notes that others have studied invisibility but says the new papers describe more precisely how to achieve it. "Each gives specific examples of how you might design an invisibility device," he says.


The authors map out the necessary speed variations and leave it to others to design the materials that will produce them. But researchers already know how to design metamaterials to achieve such bizarre properties, at least for radio waves, says Nader Engheta, an electrical engineer at the University of Pennsylvania. "It's not necessarily easy, but the recipes are there," says Engheta, who last year proposed using a metamaterial coating to counteract an object's ability to redirect light, making combination nearly transparent.


Alas, even if invisibility proves possible, it may not work the way it does in the movies. For example, a cloaking device would be useless for spying, Pendry says. "Nobody can see you in there, but of course you can't see them, either." Keeping track of your always-invisible device might be a pain, too.

So, there you have it, the first description of how to build your own invisible material.  From what I've read, it'll actually be difficult to build an invisible cloak per se, but rather, the application would be for a "shield."  As this is the US military funding this technology, I can imagine we'll be seeing (or rather, not "seeing") invisible tanks through Tehran sometime late next year (they say that it'll take them 18 months or so to actually make the material).

Got any ideas for how to put this new technology to good use?

Originally posted to verasoie on Sun May 28, 2006 at 11:27 PM PDT.


What I would do with invisibility technology:

45%9 votes
5%1 votes
5%1 votes
15%3 votes
30%6 votes

| 20 votes | Vote | Results

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Comment Preferences

  •  Tips? n/t (8+ / 0-)

    The ability to quote is a serviceable substitute for wit. Somerset Maugham

    by verasoie on Sun May 28, 2006 at 11:20:55 PM PDT

    •  Do they have to cover their eyes too? (0+ / 0-)

      Or bury their head in the sand?

      I betcha this is vapor ware.

      This would be so hard to acheive.  Its the flaws in its perceptibility that will make this thing an overpriced toy.  I hope they try to use it though.  It'd be fun to 'see'.

      Assassin: Its worse than you know. Malcolm: It usually is. 宁静

      by TalkieToaster on Sun May 28, 2006 at 11:26:12 PM PDT

      [ Parent ]

  •  I'll believe it when I don't see it! (6+ / 0-)


    Assassin: Its worse than you know. Malcolm: It usually is. 宁静

    by TalkieToaster on Sun May 28, 2006 at 11:23:38 PM PDT

  •  way above my head... (0+ / 0-)

    ... but if that said what i think it said, i'm interested to see how this would be used...

    "When I give food to the poor, they call me a Saint. When I ask why the poor have no food, they call me a Communist." [helder camara]

    by jeysiin on Sun May 28, 2006 at 11:35:26 PM PDT

  •  well this will be fun (1+ / 0-)
    Recommended by:

    when it hits the market.

    They have already made transparent aluminum, can teleport photons...

    soon I can have my own home built Klingon bird of prey...muahahahahaahaha

  •  protecting personal privacy (1+ / 0-)
    Recommended by:

    Here's one.  Online map services and similar entities are effectively providing private-sector geospatial intel that is used to invade personal privacy.  For example one of these services sells its output to city assessors, who use it to detect "unpermitted" building activity.  

    Well I'll be damned if anyone tries to tell me I need "permission" to build or modify my nest.  Squirrels sure as hell don't need permission.  And the whole idea of the "permission culture" dovetails perfectly with the "control state."  So:

    Consider an invisibility device that cloaks your house.  Prevents the sky-spies taking pictures of you when you're lounging around naked in your back yard (or having a barbeque with your dissident friends).  That would be cool.  OTOH it's also possible to do with presently-existing technology, i.e. camouflage netting and proper selection of paints and surface treatments.  

    Realistically, invisibility devices will most likely be used to cloak objects such as fighter and bomber aircraft.  Pilots will still be able to see out, via cameras and lenses.  An attacker could spot them if they knew exactly where to look, i.e. looking for a tiny camera or lens opening rather than an entire aircraft.  And of course there remains the issue of heat dissipation: all that infrared leakage, which as far as I can tell, can't be prevented entirely.  

    Interesting times ahead.  

  •  Science hype (1+ / 0-)
    Recommended by:

    Materials of this general sort are hard to make work at optical frequencies, or across more than a narrow range of frequencies. Even when they work (that is, guide light rays along the right path), they absorb much of the light as it goes through each layer. A material like this would be about as invisible as a sheet of sunglass-lens material -- or a block of tar.

  •  dude... huh, that's all i got. n/t (0+ / 0-)
  •  An Invisibility Cloak huh? (0+ / 0-)

    I'll believe it when I see it.

  •  I'm old, gray, and ugly. (1+ / 0-)
    Recommended by:
    Wee Mama

    I'm probably not really invisible but I might as well be.

  •  Difficult to do in the optical bands (1+ / 0-)
    Recommended by:

    Here's the thing. Metamaterials are structured objects, where the EM properties are determined by things like the periodicity of the structure rather than the intrinsic properties of the underlying material. The problem is that the effects require structure scale comparable to the wavelength of the EM that you want to muck with. For light, that's short, very short. To make an optical invisibility cloak, you would need "fabric" with a very precise structure down on the nanometer length scale.

    Even then, it'll probably only work for a few colors (wavelengths) of light. I'm at home, so I can't access the full-text of the article, but I'd want to know how wavelength-selective the procedure is.

    As far as the military is concerned, this is far more likely to be used for radar-cloaking planes and ships than to create the Invisible Man.


  •  Seen this? (1+ / 0-)
    Recommended by:

    A different approach to an invisibility cloak.

    Phillybits - A Showcase Of Political News And Thought

    by Stand Strong on Mon May 29, 2006 at 04:57:45 AM PDT

  •  Correction (1+ / 0-)
    Recommended by:

    You wrote:

    According to an on-line only publication in the highly reputable scientific journal Science (administered by the US Academy of Science)

    Science is actually a publication of the American Association for the Advancement of Science.  It is a 501-c-3 nonprofit, and entirely indpendent from the National Academy of Science, whose flagship publication is the Proceedings of the National Academy of Science (aka PNAS).

    The NAS is a public institution, with offices near the Vietnam Memorial on the National Mall in DC.  Membership is by an insider election/nomination process.  It is a huge honor for a scientist to be named a member of the NAS.

    The National Academy of Sciences was born in the travail of the Civil War. The Act of Incorporation, signed by President Lincoln on March 3, 1863, established service to the nation as its dominant purpose. The act also named 50 charter members.

    Over the years, the National Academy of Sciences has broadened its services to the government. During World War I it became apparent that the limited membership -- then numbering only about 150 -- could not keep up with the volume of requests for advice regarding military preparedness. In 1916 the Academy established the National Research Council at the request of President Wilson to recruit specialists from the larger scientific and technological communities to participate in that work.

    AAAS is also headquartered in DC (1200 New York Avenue), with an associated office in Cambridge England.  Membership in NAS is primarily a subscription to Science, and is available to anyone who sends in the money (<$100 per year). </p>

    Founded in 1880 on $10,000 of seed money from the American inventor Thomas Edison, Science has grown to become the world's leading outlet for scientific news, commentary, and cutting-edge research, with the largest paid circulation of any peer-reviewed general-science journal. Through its print and online incarnations, Science reaches an estimated worldwide readership of more than one million. In content, too, the journal is truly international in scope; some 35 to 40 percent of the corresponding authors on its papers are based outside the United States. Its articles consistently rank among world's most cited research.

    There is a US Academy of Science (of some sort), but I'm not familiar with it.  Google returns results on it, but it doesn't seem to have a website of its own, or a wikipedia article about it.

    Don't know if you were lazy about your sourcing, or if it was intentionally fictionalized.  If the latter, pardon me for being too literal.  If the former, you've mixed your sourcing up and undermined your credibility.

    •  My mistake, it's been corrected. (0+ / 0-)

      However, Science remains the premier scientific journal in the US, even moreso than PNAS which doesn't have as strict a peer-review system for publication by its members.

      The ability to quote is a serviceable substitute for wit. Somerset Maugham

      by verasoie on Mon May 29, 2006 at 10:35:56 AM PDT

      [ Parent ]

  •  I'm so glad (0+ / 0-)

    they are spending my tax dollars on this.  It's not as if there are any other pressing national needs to address.

    "The point is, every good candidate should have a positive agenda. But you also have to fight back." Al Franken, The Truth with Jokes, p. 104

    by Rona on Mon May 29, 2006 at 07:04:18 AM PDT

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