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Illusion Cloak Makes One Object Look Like Another
Posted by
samzenpus
on Wed May 13, 2009 05:52 PM
from the cloak-of-the-beholder dept.
from the cloak-of-the-beholder dept.
KentuckyFC writes "Metamaterials are synthetic substances that can steer light in any way imaginable. Their most famous incarnation is in invisibility cloaks which work by steering light around a region of space making any object inside that region invisible. But invisibility is just the start. A team of physicists in Hong Kong (the same guys who recently worked out how to cloak objects at a distance) have worked out how to create a cloak that makes one object look like another. Instead of steering light to make a region of space look empty, the illusion cloak manipulates light in a way that makes a region of space look as if it contains a specific object. So any object within that region of space, a mouse say, takes on the appearance of an elephant."
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Science: How To Cloak Objects At a Distance 136 comments
KentuckyFC writes "All invisibility cloaks to date work by hiding an object embedded inside them. Now a group of physicists have worked out how to remotely cloak objects that sit outside a cloaking material. The trick is to make the cloaking material with optical properties that are exactly complementary to the space outside them. Complementary means that the material reverses the effect the space has on a plane wave of light passing through it. To an observer this space would appear to vanish. The scientists say that to cloak an object sitting outside the cloaking material, first measure its optical properties and then embed a "complementary image" of the object within the cloak. So a plane wave is first distorted by the object but then restored to a plane by the complementary image of the object within the cloak (abstract). An observer sees nothing. This method has another benefit. Objects hidden in conventional cloaks are blinded because no light enters the cloaked region. But objects that are remotely cloaked like this should still be able to see their surroundings."
[+]
Science: Big Bang Could Be Recreated Inside a Metamaterial 113 comments
KentuckyFC writes "Metamaterials are substances with a permittivity and permeability that has been manipulated in a way that allows fine control over the behavior of light. They have famously been used to create an invisibility cloak that hides objects from view. Now Igor Smolyaninov, a physicist in the US, has calculated how metamaterials could be used for a much more profound demonstration: to reproduce the behavior of light in various kinds of spacetimes, in particular a (2+2) spacetime (one having two dimensions of space and two of time). His method is to show that there is formal mathematical analogy between the way metamaterials and spacetimes affect light. He goes on to show how a phase transition in a (2+2) spacetime leads to the creation of a (2+1) spacetime filled with photons, an event analogous to the Big Bang." Here are the abstract and the preprint (PDF).
[+]
Science: How To See Through an Invisibility Cloak 201 comments
AMESN writes "Ways to bend light around objects and render them invisible are becoming a major field of scientific study and gaining ground. While no actual invisibility cloak exists yet, researchers are also theorizing on how to beat the perfect cloak."
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That's some sweet stuff (Score:5, Funny)
Soon people all over can put one on their wives to have them look like supermodels... Yay!
Re:That's some sweet stuff (Score:5, Funny)
Or put one on my... you know...like they made the mouse look like an elephant?
Parent
Re: (Score:3, Insightful)
Still won't change the pleasure your new elephant can give.
Re: (Score:3, Funny)
Re:That's some sweet stuff (Score:4, Funny)
Instead of steering light to make a region of space look empty, the illusion cloak manipulates light in a way that makes a region of space look as if it contains a specific object, such as an elephant. So any object within that region of space, a mouse say, takes on the appearance of an elephant."
This is just going to piss off astronomers and give more credence to the UFO and ET enthusiasts when miscreants start projecting images of elephants floating around in the night sky.
Parent
Re:That's some sweet stuff (Score:5, Funny)
Anybody who's ever gone to a drag bar knows this is not new.
When I moved to a new apartment in Chicago's New Town in my early twenties, my roommate (native of Kansas) and I walked around the corner to get a beer after a long day of hauling furniture. The first thing we noticed was the place was full of incredibly hot girls.
Or so we thought...
Fortunately, a bartender took pity on us two naifs and clued us in before we did anything irredeemable. My buddy, who was a few beers ahead of me, took some convincing, let me tell you.
Cognitive dissonance, when it involves the little head, is tough to deal with sometimes.
Parent
Re:That's some sweet stuff (Score:5, Funny)
If they're hot and never take their pants off, what's the problem?
Parent
Re:That's some sweet stuff (Score:5, Funny)
We already have that. It's called "beer".
Parent
Re:That's some sweet stuff (Score:5, Funny)
My wife is a supermodel, you insensitive clod!
Parent
Re:That's some sweet stuff (Score:4, Funny)
Parent
Re:That's some sweet stuff (Score:4, Informative)
I don't have a wife, you insensitive clod!
Parent
Invisibility cloak?!? (Score:5, Funny)
It's Called . . . (Score:5, Funny)
Doesnt sound like much? (Score:5, Interesting)
Imagine the ability to make a tank look like a heavy truck at a distance(say to a drone), or a rocket launcher to look like a stack of pipes on satellite photos.
Re:Doesnt sound like much? (Score:5, Insightful)
We're about as close to achieving a usable cloak of illusion as we are to achieving world piece...
Parent
Re:Doesnt sound like much? (Score:5, Funny)
The only way to do it is one step at a time, so I think I'll start by getting myself a piece.
Parent
Re:Doesnt sound like much? (Score:4, Funny)
That's because there's no such thing as a cloak of illusion. It's a Hat of Disguise. Sheesh.
Parent
Re:Amazing magic tricks? (Score:5, Funny)
Are you really all that amazed by "Wow! That guy bought a product and used it! On stage!"?!?
I don't know...does it run Linux?
Parent
Re:Doesnt sound like much? (Score:5, Insightful)
Seems to me like you could just make a small tank look like a heavy truck by hanging some shit on it. Ditto for the rocket launcher situation.
Parent
Re:Doesnt sound like much? (Score:5, Informative)
There is good reason for this. If you hit a tank with something that just explodes and rains shrapnel, the hit will just bounce off, maybe destroying the optics but that is about it. You have to pierce the armor, which you do by hitting it with something very heavy and slender (such as a rod of depleted uranium) traveling at high speed that focuses a bunch of energy on one point. The heat from the collision and spalling from the armor itself then destroys whatever is behind the armor.
This does not work for a truck. If you hit it with a KE round, the round will just sail right through it. If there is nothing vital (the driver, engine, fuel lines, etc) where the KE round happens to pass, then the truck will just keep rolling. That is why you hit it with HE or MG fire. The many small bits of metal from an exploding HE round have a much higher chance of hitting something vital than the single big chunk from a KE round.
As far as a tank is concerned, you usually only get one or two shots at it before it or its buddies start returning fire. If you hit it with the wrong ammunition, he is going to kill you.
It should be noted that the inverse is also true. Making vehicles such as a truck look highly armored increases their survivability in certain situations because AT rounds are rarer than lighter ammunition and an infantry squad with a machine gun is not going attack a tank.
Parent
Re:Doesnt sound like much? (Score:5, Insightful)
Or vice versa.
Parent
Re: (Score:3, Insightful)
The disguise cloak will probably be more expensive than a rocket launcher. :)
Re:Doesnt sound like much? (Score:4, Funny)
Parent
Re:Doesnt sound like much? (Score:5, Funny)
"Sarge it looks like they're bringing out the heavy artillery, I can spot 3 Ford Escorts's and what looks like postman pat's van in the distance"
It'd be great as a car alarm / defense system, one click of a button and the car changes from a Ferrari into a Robin Reliant (let's face it no-one's going to steal one of those)
Parent
Re: (Score:3, Insightful)
Re: (Score:3, Insightful)
Imagine the ability to make a tank look like a heavy truck at a distance(say to a drone)
While that may work really well with people and detection systems that depend on light, it's probably worth pointing out that these metamaterials will probably have little affect on other methods of detection, such as radar and infrared, for example.
Metamaterials are synthetic substances that can steer light in any way imaginable
As I understand it, Drones have do have infrared cameras (as an example). Of course, that doesn't make much difference if the ground pilot is navigating entirely by the visible light camera and has to switch modes or something, but I'm not really sure how that
Re: (Score:3, Informative)
If I remember correctly the invisibility cloak that exists (how strange to write that) is for the infrared spectrum. Visible light may be harder because the range is broader, or I could be way off base. It's a gamble!
Re: (Score:3, Funny)
Why make a tank look like a heavy truck or a rocket launcher look like a stack of pipes when you could make them look like just another rock?
a rock? i was thinking more along the lines of making the tank look like a tree, and loading it up with armor piercing shells. combine a few of those with some prism tanks, and the only thing to worry about are soviet blimps.
Re: (Score:3, Funny)
Oh noez!11 *Weeeeeeep*
I see... (Score:5, Funny)
Great! This is awesome. Now, where did I put my invisibility cloak so I can fiddle with it?
Yes, the wall must be thin -- thin enough for light to pass through it. In other words, thin enough to see through without the cloak on top of it. So, in order to see through a see-through wall, we put the cloak in front of it, then make the cloak appear to be a hole, through which we can see through the see-through wall. I see.
These gedanken experiments are nice and all, but I'll believe it when I see it. Or rather, when I don't.
Re:I see... (Score:5, Funny)
It's right in front of you.
Parent
Re:I see... (Score:4, Funny)
Their idea is to create the illusion that a wall has a hole in it
BIG DEAL... Wile E. Coyote was doing this (courtesy of A.C.M.E. Corp.) since
the 1960's.
Parent
ugg (Score:5, Insightful)
Silly rabbit (Score:3, Insightful)
What makes you think there are no prototypes yet? Just because they didn't show you photos? If you were in the military, wouldn't you fly out to see these guys ASAP when you heard this? Would you give them large amounts of cash if it looked probable? Would you keep a very tight lid on any prototypes that they produced?
I am not a believer in conspiracy theories, but I would be very disappointed in
Re: (Score:3, Insightful)
Just because they didn't show you photos
Of an invisibility cloak ?
Re:ugg (Score:5, Informative)
That is because the people writing these articles have no idea what they are talking about. You can't make a mouse look like an elephant, unless you are dealing with waves much longer than an elephant, in which case that would be like making a baseball look like an elephant sized baseball, and you wouldn't be able to tell the difference between the balls or mice or elephants. Only the size of the shadow would have relevance.
Metamaterials can only cloak objects smaller than the wavelength of light you are dealing with. Once you start getting to half wavelength objects the cloaking turns to crap, and only works for a very very thin bandwidth. That wouldn't be very helpful for visible cloaking, because we see a wide range of wavelengths.
What metamaterials MAY be useful is radar cloaking. There are also applications useful for scientific instruments such as NSOM (Near-field Scanning Optical Microscope), in which you can cloak the probe so that you do not interfere with the light you are trying to measure.
Metamaterials are very interesting, but not for the layman. Move along.
Parent
Magic: yes or no? (Score:5, Interesting)
Assuming this is real, does this qualify as magic?
But can they make it bigger on the inside? (Score:4, Funny)
SETI (Score:3, Funny)
Re:SETI (Score:4, Funny)
Parent
Re:Paperclips in space? (Score:5, Funny)
If I saw a disappearing and re-appearing paperclip while looking into space through a telescope I think I'd notice...
Hi, it looks like you are trying to make an astronomical discovery. Would you like to...
Parent
vaporware (Score:5, Informative)
The summary is bad enough, talking about invisibility cloaks as if they actually exist. This and the prior work by the team are nothing more than computer models. I'm not discounting the importance of the research, just the way in which it's framed. We don't have such cloaks yet and likely won't for a long time.
It's made out of unobtanium (Score:3, Insightful)
Poor Girl's Version... (Score:4, Interesting)
http://www.boingboing.net/2009/05/04/art-student-creates.html [boingboing.net]
I think it's been done before (Score:5, Funny)
Because I've definitely seen elephants that weren't really there. And the weird thing is that they were always pink. And only showed up after I've had a few... Hmmmm.
On future uses: (Score:5, Funny)
Overheard in a girls washroom in the near future:
"Hey, there's something wrong with the faucet on this sink. No matter how much I turn the knobs, it only dispenses soap!
Dude? (Score:3, Funny)
Yeah?
You remember those mousetraps you put out yesterday?
Yeah. What about them?
Well, there's an elephant caught in one.
No shit?
Dude. What kind of cheese are you using?
Re:Military applications (Score:4, Funny)
Parent
Re: (Score:3, Funny)
Man, if only I had one of these as a kid... I would have been the undisputed champion at hide-and-go-seek!!!
I'll bet you would be. And you'd always happen to be "hiding" in the girl's locker room.
Yeah... so would I.
Re: (Score:3, Funny)