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Scientists Make Item Invisible to Microwaves
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."
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.
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.
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make install -not war
Yes, I know - this won't do that much against baryonic radiation, but for e/m . . .
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.
Suggestions for new C++ error messages, #18: "It's just an object. Doesn't mean what you think."
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.
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.