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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."
bummer.
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.
They DON'T WORK!
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.
...for making a Wing Commander reference (from the books, not the horrific movie that by coincidence has the same name) in the "department" byline for this story.
"I'd just like to emphasise that taking a million years isn't a metaphor here..." -Rich Bradshaw
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.
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.
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
It took a team from MIT to walk to the side of the object, look at the object and report that the object could be seen? I think this cloak managed to hide something other than the object....
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.
in a theoretical device, i have been theoretically impressed
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
No. But they considered a sufficiently advanced technology.
You can't see this post, oh wait, maybe you can...
Yes, I can, but 1.5 posts below where it actually is.
This ain't rocket surgery.
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.
I'm sorry, my "Disable sigs" preference has completely cloaked your sig.
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.
It's a small thermal exhaust port.
Many Bothans died to bring us the information that farting while wearing an invisibility cloak will give away your location.
You are falling right into the trap. Of course they want you to look at this cloak so that you don't notice the other one. The story is clearly part of a larger misdirection strategy. . .
"Lost time is not found again."