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Fatal Flaw Discovered In Invisibility Cloaks
KentuckyFC writes "Carpet cloaks took the world by storm last year because they were the first devices to hide objects at optical frequencies. The idea is that a thin layer of dielectric material placed on a surface can make light look as if it is reflecting off the original surface. In other words, the layer is invisible and anything embedded within it is invisible too. This trick is like hiding something under a carpet, hence the name. Carpet cloaks are relatively easy to make because the dielectric material does not need to be specially constructed to steer light in special ways; physicists call this an isotropic material. Now a group at MIT has shown that isotropic carpet cloaks have a fatal flaw. When viewed at an angle, the carpets don't hide objects at all. Instead, they simply shift their position by about the same distance as they are high. So when viewed from an angle of 45 degrees, an object 0.2 units high is shifted to one side by a distance of 0.15 units, says the team. That's a serious limitation for carpet cloaks."
I'm sure a carpet cloak like this would have military applications, and in a desert environment like the Middle East, people aren't going to notice you unless they're close to you.
A sniper on a ridge covered with one of these babies is still going to do the job.
What happens when you layer them? I mean, if you overlap a bunch of these invisibility carpets, what would you end up looking at?
So when viewed from an angle of 45 degrees, an object 0.2 units high is shifted to one side by a distance of 0.15 units, says the team. That's a serious limitation for carpet cloaks.
Maybe. But it would be a great way for soldiers to conceal themselves from aimed rifle fire.
Display some adaptability.
I don't know about you, but when I hear the phrase "fatal flaw," I really expect something a little more, I don't know... hilarious.
"This thing does science so hard, you say, 'I've never seen that much science.'" -Sam
Depends on the size of the missile...
What is that in Libraries of Congress?
"This thing does science so hard, you say, 'I've never seen that much science.'" -Sam
They don't have to be perfect; they just have to be good enough. Nor do that have to work all the time; they just need to work when needed, and for just long enough to allow the first shot. ("Spock, what's tha...doh!")