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Scientists Closer To Invisibility Cloak
Aviran was one of many readers to submit news of a just-announced development in the ongoing quest to develop a working invisibility cloak, writing: "Scientists say they are a step closer to developing materials that could render people and objects invisible. Researchers have demonstrated for the first time they were able to cloak three-dimensional objects using artificially engineered materials that redirect light around the objects. Previously, they only have been able to cloak very thin two-dimensional objects" Reader bensafrickingenius adds a link to coverage at the Times Online, and notes that "the world's two leading scientific journals, Science and Nature, are expected to report the results this week." Tjeerd adds a link to a Reuters' story carried by Scientific American.
Scientists closer to fulfilling fantasy of hiding in girl's locker room.
Do you even lift?
These aren't the 'roids you're looking for.
This was posted in Pharyngula yesterday. The usual prescient commenters noted that nowhere on the researchers' pages was there active speculation about an "invisibility cloak", and it was probably just some reporters going wacky over the possibilities. http://scienceblogs.com/pharyngula/2008/08/get_your_invisibility_cloak_he.php
Well, the body radiates heat. Even if your suit could bend those, its going to end up heating up to skin temperature. Once that happens, its all over. It can bend IR where ever it wants, but since IR from a human body is relativity uniform to begin with (and you don't need detail to see a human figure heat blur on a IR sensor), you're still going to get a human shaped object on your IR sensors.
No, the light gets bent around it perfectly. The light coming in from the background enters the metamaterial, is bent around to the other side of the object and exits it just as if it had passed through the area enclosed by the metamaterial without any obstacles. Ideally, there is no way that an observer could tell the difference with the exception of knowing the time of travel. The path through the metamaterial is longer than that of the perceived path. I would think that if the shrouded object was in front of a large reflector of a known distance from a radar like source, then the added delay in the signal would add a very small amount of distance to the location of the reflector. An astute observer with very good equipment may notice a change in the position of the radar returns as a cloaked object crosses through. There are further exceptions that are introduced the more you start to use the theory in practice, the biggest problem being that the current solutions would require that an object be encased in a spherical shell of metamaterial, not the most convenient situation. In addition, the current crop of metamaterials have very small bandwidths, making the cloaked object perceptible to other detection methods. If you cloaked for the visible (and actually could cover the entire visible region) then you would probably be easily picked up via radar or infrared imaging.
I know everyone is making with the jokes,but I for one really don't like the idea of this. Yet again,we have scientists seeing if they CAN do something,rather than if they SHOULD do something. As aggressive as the US has been lately,does anyone really want gunships,fighter jets,and whole squads of special forces rendered invisible?
Hear hear! Perhaps we should revise the Geneva convention. From now on, all snipers must jump up and down waving their arms and yelling "Look at me" before taking their shot. All submarines must have PA systems that continually blast Rick Astley music when they're submerged. All spy drones must broadcast Flight of the Valkyries when on a mission.
I understand your point but, as long as the world has weapons, governments will be spending money on improving them (range/cloaking/accuracy/flexibility/etc.) If you go to the government leaders who control weapons funding and ask them "Should this weapon be improved?", once they're done laughing the answer will certainly be "Yes." And, assuming that this product would be fielded for military use as you imply, it would be seen as a measure to both increase our effectiveness on the battlefield and protect our troops. That would change the government's answer from "Yes" to "Hell yes." Right? Wrong? Doesn't matter - just the world we live in.
He's getting rather old, but he's a good mouse.
While we are limiting ourselves from creating an invisibility cloak do we have to ban warfare at night and stealth aircraft? I mean, those things just aren't fair. In fact let's get rid of guns, camouflage, body armor, aircraft, and submarines. We can settle things with a boxing match. Technological advances in warfare has continued for centuries now. We've been down this path before with other technology but I wouldn't be too worried. Just as devices like these are created others are created to defeat them. It is the natural progression of weapons.
Time makes more converts than reason
Even a perfect optical cloak would still be detectable in many ways. Bear in mind that wearing a perfect optical cloak will render you blind. This means you'll have to navigate using other methods. You could wear infrared goggles, but that means you're visible in infrared light and therefore detectable. You could make yourself invisible to all wavelengths, perhaps, and then navigate by sonar. A microphone will pick that up easily enough. Likewise radar. You could, I suppose, navigate via a remote camera signal that displays your surroundings on a screen located inside the cloaking device. That would be disorienting but one could probably train for it or use a VR representation of your surroundings. Assuming, then, that you can obfuscate the video signal and avoid emitting any light yourself, then you'll be foiled by a cheap fog curtain at the entrance of a building. Or, if you want to be more practical about it, a metal detector. If the target of your assassination attempt is outdoors, you'd best hope that there's no precipitation, smoke, smog, or fog. And you won't be able just to point and shoot, either. Remember, you're blind.
Even assuming a partial optical cloak that lets you be invisible "enough" (perhaps in shadows) and still see somehow, you'll still be detectable. If this technology becomes available, technology to defeat it will, too. Off the top of my head... a sonar or radar (preferably sonar, I think humans are transparent to radar) system that compares the visual or infrared spectrum with the echos. You probably wouldn't even need a human to operate it; a computer could simply find the discrepancies between the images and report them. A detection system like this would probably be affordable even to smaller nations. If you wanted to get really paranoid, you could even have the computer automatically target human-shaped echo discrepancies and fire long range or remote tasers at them, killing the cloak as soon as it is spotted.
Or, save yourselves all the trouble, sprinkle sand everywhere and just watch for footprints. Or hold all public events in the middle of huge, 2-inch deep lakes.
End of lesson. You may press the button.
Then you'd be a dark spot, or two dark eye shaped spots.
--why?