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Scientists Make Item Invisible to Microwaves 219

Vicissidude writes "A team of American and British researchers has made a cloak of invisibility. In their experiment the scientists used microwaves to try and detect a copper cylinder. Like light and radar waves, microwaves bounce off objects making them visible and creating a shadow, though it has to be detected with instruments. If you can hide something from microwaves, you can hide it from radar and visible light. In effect the device, made of metamaterials — engineered mixtures of metal and circuit board materials, which could include ceramic, Teflon or fiber composite materials — channels the microwaves around the object being hidden. When water flows around a rock, co-author David R. Smith explained, the water recombines after it passes the rock and people looking at the water downstream would never know it had passed a rock. The first working cloak was in only two dimensions and did cast a small shadow, Smith acknowledged. The next step is to go for three dimensions and to eliminate any shadow."
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Scientists Make Item Invisible to Microwaves

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  • Just talking... (Score:2, Interesting)

    by nathan s ( 719490 ) on Thursday October 19, 2006 @01:57PM (#16504545) Homepage
    ..from my ass, so to speak, but I imagine you could leave certain frequencies uncloaked, enough to slip in, say, remote video from a drone flying nearby or surveillance cameras in the area or GPS satellites in the case of bots. Perhaps a super-advanced version could shift cloaked frequencies on the fly in order to prevent jamming/detection of the video source even. I dunno, if this works in the first place it seems like there should be ways around the "blindness."
  • Quite some time. (Score:3, Interesting)

    by AltGrendel ( 175092 ) <ag-slashdot.exit0@us> on Thursday October 19, 2006 @01:58PM (#16504555) Homepage
    This was already addressed to some degree in the SciFi book "The Last Mortal Man". The reasoning for making them illegal was that the criminal element used them to evade law enforcement. I'm sure the DHS would have alot to say about this.
  • Re:Quite some time. (Score:3, Interesting)

    by the Gray Mouser ( 1013773 ) on Thursday October 19, 2006 @02:01PM (#16504603)
    Ok, on a serious note then:

    How long till we see military issue suits? They wouldn't have to be perfect to be a big help to infantry in medium cover terrain.

    Of course, almost anything military gets a civilian version eventually, so we're back where I started.
  • by Doc Ruby ( 173196 ) on Thursday October 19, 2006 @02:12PM (#16504791) Homepage Journal
    I'll go out on a limb on a series of "ifs" (and maybe a bag of physics naivetes), but let's say we perfect this manner of imperceptibly "derefracting" light. And let's say we also complete the ambitious work identifying and manipulating gravitons, still hypothetical. Could we "cloak" spaces and matter from any interaction with our universe, not just electromagnetic? Maybe the Stong and Weak Forces would remain for interaction, but practically, outside the tiny diameter of a nucleus, could anyone notice?

    Could a "gravity cloak" create subspaces operating as independent universes? Could we contain matter too highly interactive for current use safely? Like a tiny black hole conveniently near a device it's powering, or a pair coupled into a wormhole for "faster than light" travel through custom-folded space? Vast amounts of stuff crammed into pocketsized spaces.

    Maybe the old playground philosphers choosing between "teleportation or invisibility superpowers" will finally have a lab to figure out which is really better.
  • by mmell ( 832646 ) on Thursday October 19, 2006 @02:19PM (#16504917)
    Without debating the practical aspects of invisibility, I do have to wonder if this could be useful as some sort of radiation shielding? If they're able to do it for more energetic forms of e/m than microwave radiation, it seems to me that it would make an excellent shield. It doesn't have to be perfect invisibility, allowing me to "peek out" of the shield is fine. It doesn't even have to be non-detectable - I don't mind a visible "energy distortion" or "energy turbulence" or whatever - I just don't want to get fried.

    Yes, I know - this won't do that much against baryonic radiation, but for e/m . . .

  • Re:Quite some time. (Score:5, Interesting)

    by Rei ( 128717 ) on Thursday October 19, 2006 @02:27PM (#16505093) Homepage
    And the biggest beneficiary of infantry invisibility suits? Guerilla fighters.

    Sure, they won't get them right away. But you better believe that they'll try to capture them, and any state sponsors that they have immediately try and produce or otherwise acquire them. Big armies, trying to cloak things like tanks driving down the stret, will have a much harder job at it than fighters simply hiding themselves and their RPG, already in the shadows or buildings. Not to mention things like pressure or vibration-triggered mines/IEDs won't be affected, which also benefits guerilla fighters on their own turf.
  • by mark-t ( 151149 ) <> on Thursday October 19, 2006 @02:30PM (#16505151) Journal
    If you bend the lightwaves around yourself so that they can continue moving past you, what light waves can enter your eyes, exactly? You'd be in pitch darkness, unable to see a damn thing because the light can't get to you because it's being bent around you. If you choose to allow some light through so you can see, then other people would see blackness there because there's light that's not getting reflected by anything... again, useless.
  • Re:Quite some time. (Score:3, Interesting)

    by beyowulf ( 1014741 ) on Thursday October 19, 2006 @02:51PM (#16505599)
    I suppose they'd have to make the cloak invisible to the visible spectrum and provide goggles to see the non-visible(Infared, UV) spectrum.
  • Re:hmm, (Score:1, Interesting)

    by Anonymous Coward on Thursday October 19, 2006 @02:57PM (#16505711)
    Can you say boost and split? No reason why the light can't be routed and diverted.
  • by wyldeling ( 471661 ) on Thursday October 19, 2006 @05:25PM (#16508611) Homepage
    Point. Let me clarify. Mathematically, they are the same thing. The principle of least action applies in both cases, just the path the minimizes the particular Lagrangian (T - V) [] (or Hamiltonian (T + V) [], if you prefer) differs depending on the potential energy. (Both methods are applications of the Calculus of Variations []. ) Either way, it is a minimization problem and the same techniques apply. So, as far as I'm concerned, they tend to blend together.
  • Re:Quite some time. (Score:2, Interesting)

    by clambake ( 37702 ) on Thursday October 19, 2006 @09:49PM (#16511557) Homepage
    Ah, but there is a SECOND way to use the cloak...

    Imagine cloaking thousands of giant baloons and floating them over your city... In come the bombers, and whoops there is another baloon in the air intake, there goes a $2 billion bomber for the price of a $45 baloon!

  • Re:Quite some time. (Score:3, Interesting)

    by iluvcapra ( 782887 ) on Thursday October 19, 2006 @11:37PM (#16512389)
    The way you describe it, military cloaks of invisibility would seem to be plainly illegal under the Hague Conventions [], supposing that killing an enemy while you are invisible translates as a "treacherous act," by Article 23. Also if you engaged in combat under a Cloak you would be necessarily trading in your protections under GC1 and 3.

In 1869 the waffle iron was invented for people who had wrinkled waffles.