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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."
So what they're saying is it's more of a Cloak of Displacement? While less stealthy, I think that's actually better odds of avoiding the hit than the penalty for attacking an invisible opponent.
Yeah - you aren't invisible, but wouldn't that still make the tracking missile miss you?
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.
When they were creating these cloaks, they didn't think to look at it from other angles than just straight on? Seriously? That's the equivalent of "it works on my machine."
At last, my sig is actually appropriate for a slashdot story!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
You could bump into the invisible object.
I can't see how they could work.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
I demand more pictures of invisibility cloaks in articles about invisibility cloaks. Theory be damned.
Please stop pluralizing words with an apostrophe. That is not what it is there for.
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.
They should be working on a "Somebody Else's Problem" field. I hear that this is much easier than trying to much around with physics.
No, the fatal flaw is that a cloaked object moving at warp speed emits a slight subspace variance. Adversaries performing an antiproton scan may also be a problem.
From TFA:
Zhang and co go on to prove their assertion by tracing a ray that passes through the kind of isotropic carpet cloak that Pendry suggested. What they've discovered will shock carpet cloakers all over the world.
Yeah, all over the world.... uhm, all three of them. (Emphasis mine)
The three that YOU CAN SEE...
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
What if we modify the phase variance?
I am amused at the correlation between your comment and your sig. Well done, sir.
Whatever it is, it's notablog.
They did. Then they switched it on, and ever since they are seeking the device.
The Tao of math: The numbers you can count are not the real numbers.
I mean, I know we all understand it, but if you're giving an example, why use unitless decimals when you can use integers and tangible concepts? Why not just say it would displace a 4 meter tall truck by 3 meters instead of 0.2 units tall object by 0.15 units?
This sentence no verb.
What if we modify the phase variance?
yeah, as long as we randomly modulate the shield frequencies, reverse the polarity of the heisenberg compensators, and amplify the transporter buffers... we should be good to go. Earl Grey tea never tasted so good.
Well, cheer up. It might still mean that the Romulan's weapons hit some nearby console when they think they're targeting the warp core. Of course, it would be better if they didn't hit anything at all, but I'm affraid that the law that for each hit a console must explode in a shower of sparks and send some ensign flying across the room is more immutable than the laws of refraction ;)
A polar bear is a cartesian bear after a coordinate transform.
Unfortunately, every member of the search team is slacking off, assuming someone else is looking for it.
Nah, that can easily be defeated by a tachyon burst, particularly if you invert the polarity of the shield harmonics.
What if we modify the phase variance?
yeah, as long as we randomly modulate the shield frequencies, reverse the polarity of the heisenberg compensators, and amplify the transporter buffers... we should be good to go. Earl Grey tea never tasted so good.
Now see here... If the polarity of anything is to be reversed, then clearly we should start with the neutron flow...
Bow-ties are cool.
This solution will never work.
No one has even suggested routing extra power to the main deflector array yet.
DRM: Terminator crops for your mind!
No, no, no. You need to narrow the angular confinement beam.
I can't see how they could work.
This is only about 'carpet cloaks', not invisibility cloaks in general. The problem is that a carpet cloak is the optical analogue of simply putting a display screen in front of the object and a video camera behind the object. In other words, of course it doesn't bloody work from the side, you morons. A general invisibility cloak is still possible, but may require phased array optics or other exotic active techniques.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.