InvisibilityCloak
Latest
Invisibility cloak modified to make you see things that aren't there
The ever-evolving tale of the invisibility cloak makes us want to hang our heads in our hands sometimes, so fraught with frustrations does it seem. Well, another chapter's been added to the tome: researchers at the Hong Kong University of Science and Technology have devised a way to extend the invisibility principle, allowing an illusion to sit in place of the invisible object. So, say you wanted to use an invisibility cloak to mask the presence of your bottle of beer on the table, the new concept -- or 'shroud of lies' as we call it -- would enable you to make it appear that there was a glass of water sitting there, in place of the beer. So how does that work, exactly? Normal, every day invisibility cloaks bend light around a central cavity, whereas the team has now worked out mathematical rules for bending light in other ways, allowing a material to be designed to bend light in the exact way a spoon would, so that the light hitting the material would distort, making it look like a spoon was there. Theoretically, all of this is rather simple and quite sound, though it turns out that there are numberless mechanical obstacles standing in the way of producing such devices. The new illusion-producing device would have to be capable of working without interfering with the invisibility cloak itself (which, if you recall, also can't properly be said to exist). There's no word on when any of this will ever come to fruition of course, but we remain always hopeful.
Acoustic superlens could mask ships from sonar... in theory, anyway
Man, the mad scientists are really on a roll of late. First we hear that Li-ion cells are set to magically double in capacity, and now we're learning that a new form of invisibility cloak is totally gearing up for its Target debut. As the seemingly endless quest to bend light in such a way as to create a sheath of invisibility continues, the University of Illinois at Urbana-Champaign's Nicholas Fang has reportedly developed a metamaterial that acts as a type of acoustic superlens. In theory, at least, this approach would rely on phreaking with sound rather than light in order to intensely focus ultrasound waves; by doing so, one could hypothetically "hide ships from sonar." To be fair, this all sounds entirely more believable than hiding massive vessels from human sight, but we're still not taking our skeptic hat off until we see (er, don't see?) a little proof.[Via Slashdot]
Purdue researchers concoct new invisibility cloak, plan Walmart debut
Hate to say it, but we're beyond the point of hope here. We just won't ever, ever see a real-deal invisibility cloak during our relatively brief stint on Earth. That said, researchers at Purdue University are doing their best to prove us wrong, recently developing a new approach to cloaking that is supposedly "simple to manufacture." Unlike traditional invisibility cloaks, which rely on exotic metamaterials that demand complex nanofabrication, this version utilizes a far simpler design based on a tapered optical waveguide. A report from the institution asserts that the team was able to "cloak an area 100 times larger than the wavelengths of light shined by a laser into the device," but for obvious reasons, it's impossible to actually show us it happened. Regardless, for the sake of the kiddos above, we're hoping this stuff gets commercialized, and soon.[Via Digg, Image courtesy of Thomas Ricker (yes, that Thomas Ricker)]
Quest for invisibility cloaks revisited by two research groups
After a brief period of no news, it's time to revisit the world of invisible cloaks. Inspired by the ideas of theoretical physicist John Pendry at Imperial College, London, two separate groups of researchers from Cornell University and UC Berkeley claim to have prototyped their own cloaking devices. Both work essentially the same way: the object is hidden by mirrors that look entirely flat thanks to tiny silicon nanopillars that steer reflected light in such a way to create the illusion. It gets a bit technical, sure, but hopefully from at least one of these projects we'll get a video presentation that's sure to make us downright giddy.
Cloaking device puts the kibosh on cellphone interference
There has been plenty of research into cloaking devices, but while scientists are still working their way towards the visible light spectrum they seem to be having the best luck with microwaves. Most recently, a new metamaterial made from over 10,000 individual pieces of fiberglass has been used to cloak a bump on a flat mirrored surface -- the material prevents microwaves from being scattered, giving the RADAR (we're guessing it's a RADAR) the impression that the surface is flat. This has many possible applications, such as cloaking sources of interference to cellular communications. Unfortunately, the implication we most desire -- rendering us invisible during high society jewel heists -- has yet to become reality.
Researchers create light bending material for invisibility cloak
We're only at the nano scale folks so you'll have to keep those high school fantasies of an invisibility-cloaked romp through the girls' locker room tucked away for now. Still, two teams of US government funded researchers under the direction of Xian Zhanga at UC Berkeley say that they've developed a material which can bend visible light around 3D objects, effectively making them disappear. While similar to the negative refractive properties of materials developed back in 2006, UCB's so-called meta-material is easier to work with and absorbs far less light than those earlier products. As such, the material could scale to the size of invisibility cloaks to hide objects such as tanks or mischievous boy-wizards. However, that day is a long ways off. In the short term, the meta-material will most likely find use in the far less interesting (to consumers, anyway) application of building better microscopes. Hey, Xian, picture of your invisible material or it didn't happen... oh, wait.[Via BBC News]
Researchers say three-dimensional sound cloak is possible, in theory
Apparently not content with simply building an invisibility cloak, of sorts, those mad scientists at Duke University's Pratt School of Engineering now say that they've found that a three-dimensional "sound cloak" is also possible, in theory. According to Duke's Steven Cummer, the researchers have come up with a "recipe" for an acoustic material that would "essentially open up a hole in space and make something inside that hole disappear from sound waves." Needless to say, they haven't tested that possibility just yet, but they say it could one day be used to hide submarines from detection by sonar or even be used to improve the acoustics of a concert hall by making inconvenient structural beams effectively disappear. What's more, they say that the basic principles at play here could also suggest that cloaks could be created for other wave systems, like seismic waves, or even waves at the surface of the ocean, although the practical applications for those would seem to be a bit more limited.[Image courtesy of Royal Navy/BAE Systems]
Duke scientists build theorized invisibility cloak. Sort of.
Yes, everyone wants an invisibility cloak. Yes, it's been theorized and in development before. But now, what our friends across the pond have only imagined, scientists at an American university have actually built. A group of brainiacs at Duke University have built a device (based on the Imperial College London theory) that can deflect microwave beams so the beams flow around an object almost as if nothing was there, with not too much distortion (but only in two dimensions). In order to do this, the group built a series of concentric circles made up of "metamaterials," or "artificial composites that can be made to interact with electromagnetic waves in ways that natural materials cannot reproduce." Don't get too excited yet, as scientists warn that this is merely a "baby step." The next step is to make the cloak work in three dimensions, and make improve the cloak's effectiveness. And even still, we're a long way off from making something completely disappear from visibility, which "would have to simultaneously interact with all of the wavelengths, or colors, that make up light." said David R. Smith, a member of the research squad. Hey Duke team, if you ever need human test subjects, we'd definitely be willing to volunteer.[Via The Associated Press]
