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Making a Liquid Invisibility Cloak

ScuttleMonkey posted more than 4 years ago | from the pour-to-order dept.

Science 93

Researchers at Fudan University in Shanghai, China are proposing a method which could lead to the first soft, tunable metamaterial, the key ingredient in building an invisibility device. "The fluid proposed by Ji-Ping Huang of Fudan University in Shanghai, China, and colleagues, contains magnetite balls 10 nanometers in diameter, coated with a 5-nanometer-thick layer of silver, possibly with polymer chains attached to keep them from clumping. In the absence of a magnetic field, such nanoparticles would simply float around in the water, but if a field were introduced, the particles would self-assemble into chains whose lengths depend on the strength of the field, and which can also attract one another to form thicker columns. The chains and columns would lie along the direction of the magnetic field. If they were oriented vertically in a pool of water, light striking the surface would refract negatively – bent in way that no natural material can manage."

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Liquid Invisibility Cloak? (3, Funny)

Anonymous Coward | more than 4 years ago | (#30697868)

It's been a while but isn't that a shot of Bacardi 151 mixed into a glass of ice tea garnished with a lime?

Re:Liquid Invisibility Cloak? (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30697914)

I have blue balls.

Re:Liquid Invisibility Cloak? (1)

JWSmythe (446288) | more than 4 years ago | (#30698274)

    No, no, that's the power of invincibility. But can I get that without the tea or lime. I don't need any of that girlie crap thinning out my liquor.

Re:Liquid Invisibility Cloak? (2, Insightful)

Darinbob (1142669) | more than 4 years ago | (#30704382)

If I want to be invisible, I walk into a singles bar full of women and announce that I'm available. Suddenly no one can see me.

Re:Liquid Invisibility Cloak? (1)

JWSmythe (446288) | more than 4 years ago | (#30705022)

    [sound of crickets]

    Did someone say something?

Let's get this over with... (-1, Redundant)

lorenlal (164133) | more than 4 years ago | (#30697878)

[Insert lame Harry Potter joke here]

LuLz!

Re:Let's get this over with... (2, Funny)

Anonymous Coward | more than 4 years ago | (#30697912)

Oh ho ho ho ho!

I didn't see that one coming.

Did that joke have an invisibility cloak too?

Re:Let's get this over with... (4, Funny)

lorenlal (164133) | more than 4 years ago | (#30698214)

Apparently you saw right through that one.

Re:Let's get this over with... (1)

LifesABeach (234436) | more than 4 years ago | (#30699902)

its 6:00am, I get up to go to the bathroom, I casually sit down while trying to wake up. WHO LEFT THE INVISIBILITY CLOAK ON THE TOILET!!!

Re:Let's get this over with... (1)

drummerboybac (1003077) | more than 4 years ago | (#30697932)

I was gonna go with the more obscure Way of the Shadows and say it sounds like they are making a ka'kari

Re:Let's get this over with... (0)

Anonymous Coward | more than 4 years ago | (#30698448)

I anonymously thank you for introducing me to the Night Angel Trilogy. I'll have to do some more research, but it looks like an interesting trilogy.

Re:Let's get this over with... (0)

Anonymous Coward | more than 4 years ago | (#30698326)

[Insert lame Harry Potter joke here]

Harry: So we started out last night at the inn pounding liquid invisibility cloaks until Ron looked kinda cute ...

anonymous coward (0)

Anonymous Coward | more than 4 years ago | (#30697888)

Sounds very unlikely. We'll have magic wands way before invisibility cloaks.

Re:anonymous coward (1)

JWSmythe (446288) | more than 4 years ago | (#30697998)

    We already have those. I change channels on TV with them every night. And, be damned if you're going to take my magic stick away from me. Taking it away is like taking food from an angry dog. I don't care if you don't want to watch the Mystery Science Theater marathon, *I* have the magic stick!

Re:anonymous coward (4, Funny)

Red Flayer (890720) | more than 4 years ago | (#30698432)

We need some disambiguation, though. My "magic stick" seems to be very different than your "magic stick". Yours is likely black or silver; mine varies from light tan/pink to purplish. I'm sure there are other differences as well.

As a matter of fact, my "magic stick" is superior to yours, since I can cede control of it to my wife and still watch MST3K marathons.

Re:anonymous coward (0)

Anonymous Coward | more than 4 years ago | (#30699462)

... As a matter of fact, my "magic stick" is superior to yours, since I can cede control of it to my wife and still watch MST3K marathons.

Or play games or drive...

Mario Cart Road Head for the Weeeee!

Re:anonymous coward (0)

Anonymous Coward | more than 4 years ago | (#30700114)

thats was like the gayest comment ever read on /.. not that theres anything wrong with being gay......

Re:anonymous coward (1)

JWSmythe (446288) | more than 4 years ago | (#30704992)

I think I understand your confusion. But it's not exactly appropriate to call Mjollnir (Thor's Hammer), a "magic stick". That's like calling a lightning bolt sent from high above Mount Olympus by Zeus just a "pretty light".

    Magic stick works the electronics.

    Mjollnir bangs your wife. :)

I'm not seeing it (0)

Anonymous Coward | more than 4 years ago | (#30697898)

eom

Future Commercial Success Guaranteed (1)

postmortem (906676) | more than 4 years ago | (#30697922)

Much cheaper way to hide weight than liposuction/gastric bypass and available in Walmart..

What is so great about the invisibility cloak? (4, Funny)

Anonymous Coward | more than 4 years ago | (#30697938)

I don't understand all these invisibility cloak stories on Slashdot over the years. Is it rooted in some fantasy about being invisible in the girl's locker room?

Re:What is so great about the invisibility cloak? (5, Funny)

jellomizer (103300) | more than 4 years ago | (#30698272)

Um no you are a sick mind... It is for the Woman's locker room.

Re:What is so great about the invisibility cloak? (1)

happy_place (632005) | more than 4 years ago | (#30698972)

So WRONG! No. For slashdotters, it would be for scientific research into the daily life of the female species.

Not to stomp on ur parade.... (1, Interesting)

Anonymous Coward | more than 4 years ago | (#30698554)

Actually no, just the fact of being invisible. In order to be invisible you have to refract all the light that would normally hit the object being invisible, meaning it would be in absolute dark. You could be invisible in the girls (or guys for the /.ers so persueded) shower room, but you couldn't see a blasted thing. Any lighted object within the cloak could also, possibly, leak out giving away your concealment. So even IF (a big if) the use of, say, an infrared camera, would allow you to see through the cloak, the use of it would give you away as the light from the screen/goggles could give you away. Not to mention you would have to use some containment of the matrix supporting the nano-particles (the fluid). A magnetic field strong enough to suspend water (i'm not even sure if there is such) would likely throw off the magnetic particles, so in turn you would need to have some sort of containment beyond the aqueous sphere. Think fishbowl. The container (fishbowl) in turn, would be visible being outside the sphere of invisibility. So you would see this great 'empty' spherical container just sitting there. Which, logic denotes, means the rat got out, elliciting chaos and panic in said locker room.

This is just one of the great physics problems that everyone has to come up with an 'answer' to, and get their jollies just from doing that. If you wanna be invisible in the girls shower room the best bet is still a very small drill and a pinhole camera, as any A/V geek knows all too well.

Re:What is so great about the invisibility cloak? (2, Insightful)

mysidia (191772) | more than 4 years ago | (#30698604)

Your average slashdot reader is:

  • A Harry Potter fan, and sees how useful an invisibility cloak can be in certain situations.
  • A star trek fan
  • An aspiring Klingon, knows the language, can't make surprise attacks without a cloak shield
  • A Linux user
  • A user of whole-drive disk encryption
  • Has a UPS, lots of batteries, or other form of backup power
  • In need of a cloaking device, for that one last piece of the security puzzle (keeping the machine safe from physical hackers)

Re:What is so great about the invisibility cloak? (3, Insightful)

Nadaka (224565) | more than 4 years ago | (#30698998)

Bah. thats just security through obscurity.

Re:What is so great about the invisibility cloak? (1)

mysidia (191772) | more than 4 years ago | (#30711320)

Slightly better than obscurity... being invisible is a little different from being obscure :)

Either way, invisibility is all you need to prevent girlfriend from walking in and seeing you watching porn.

Oh wait... slashdot.... uh... neighbors?

Anyways, a physical attacker needs to be able to see your machine before they can steal it.

If they can't see where it's located, they won't be able to get in and grab it before the burglar suppression system goes off and knocks them out.

They won't be able to tell whether you moved it to your underground vault or not, since it'll be invisible from your window, either way

Re:What is so great about the invisibility cloak? (1)

McGiraf (196030) | more than 4 years ago | (#30699040)

"In need of a cloaking device, for that one last piece of the security puzzle (keeping the machine safe from physical hackers)"

No! No! that would be security by obscurity!

Re:What is so great about the invisibility cloak? (1)

aldld (1663705) | more than 4 years ago | (#30703348)

I'd rather be invisible in a chocolate factory.

Countermeasure (2, Funny)

argent (18001) | more than 4 years ago | (#30697956)

You can see through them with beer goggles.

Just in time... (1)

sznupi (719324) | more than 4 years ago | (#30697980)

...for the era of Chinese domination.

Re:Just in time... (0)

Anonymous Coward | more than 4 years ago | (#30698352)

Some time around 2077, in Alaska...

Theoretical material with exotic optical effects (0)

fridaynightsmoke (1589903) | more than 4 years ago | (#30698008)

!= "invisibility cloak"

Re:Theoretical material with exotic optical effect (3, Funny)

ZorbaTHut (126196) | more than 4 years ago | (#30698062)

Similarly, a hunk of silicon with strange electrical properties isn't a computer. And yet, the former is very useful if you want to build the latter.

Do you, like, just not understand how science works?

Re:Theoretical material with exotic optical effect (2, Interesting)

fridaynightsmoke (1589903) | more than 4 years ago | (#30698254)

Similarly, a hunk of silicon with strange electrical properties isn't a computer. And yet, the former is very useful if you want to build the latter.

Do you, like, just not understand how science works?

My ire was directed at the reporting, not the discovery or researchers (who I wish good luck).

Calling this discovery "Making a liquid invisibility cloak" is like calling the discovery of a new, slightly higher temperature superconductor "Making warp-capable flying cars".

Maybe sensational reporting of just about everything (eg the LHC) is causing the public's lack of affinity for science. All they see is hundreds of 'broken promises' made by the media about fantastic whizz-bang technologies that the research they are reporting on isn't even working towards.

Re:Theoretical material with exotic optical effect (0)

Anonymous Coward | more than 4 years ago | (#30698550)

actually it is because the public thinks the idea of these things working is actually cooler than if they actually exist. After you imagine something, if it takes a long time for it to actually work, the public is really bored with the idea already. It is only when one of these ideas has other capabilities that were never thought of before, maybe because the invention was not realized, that actual inventions become interesting again. When you have a connection with an object that you never would have thought before was possible. The media just creates the stories, because that is actually what the public cares about: the ideas, rather than the reality. Humans are dreamers above anything.

Re:Theoretical material with exotic optical effect (1)

kdemetter (965669) | more than 4 years ago | (#30701050)

Humans are dreamers above anything.

A good thing too , otherwise there wouldn't be any inventions.
The problem is , just an idea isn't good enough : you need a plan to put it into practice , and you need money in order to bring it into a workable product.

That means you have to find investors, and 'Liquid Invisibility Cloak' sells better than 'Theoretical material with exotic optical effect' .

Re:Theoretical material with exotic optical effect (2, Funny)

Mister Whirly (964219) | more than 4 years ago | (#30699336)

So sweet! Where can I get one of these new warp-capable cars??

Re:Theoretical material with exotic optical effect (1)

Sanat (702) | more than 4 years ago | (#30703334)

It's sitting right in front of you, but it's covered with an invisibility cloak.

Re:Theoretical material with exotic optical effect (2, Funny)

homey1337 (1656791) | more than 4 years ago | (#30698084)

an SEP field is better anyway

Re:Theoretical material with exotic optical effect (2, Funny)

daveime (1253762) | more than 4 years ago | (#30698258)

It's impossible to actually create an SEP field, because of course the ideas, research and manufacture are all SEP !

Isn't this overkill? (2, Insightful)

madbox (187860) | more than 4 years ago | (#30698090)

I mean, Aquaman is enough of a badass already, isn't he?

Re:Isn't this overkill? (1)

Culture20 (968837) | more than 4 years ago | (#30699178)

I mean, Aquaman is enough of a badass already, isn't he?

Monarch, super-strength, harpoon, magic water control, now invisibility. These things are _necessary_ to combat the Superfriends Aquaman.

Re:Isn't this overkill? (1)

Whiteox (919863) | more than 4 years ago | (#30706384)

I'm more concerned about invisible sharks with lasers on their heads.

Only works from one perspective? (3, Funny)

drdrgivemethenews (1525877) | more than 4 years ago | (#30698114)

I can understand how they could use these materials (theoretically anyway) to make Julian Beever-style illusions (see http://www.moillusions.com/2007/12/julian-beevers-new-3d-sidewalk.htm [moillusions.com] ). But a real invisibility cloak has to detect the direction of every photon striking it and deliver that proton in the same direction out the exact opposite side of the cloak, doesn't it? Otherwise the effect is likely to be like a Beever painting, viewable from only one precise viewpoint.

-------

Theory blazes the trail, but it can't pave the road

Re:Only works from one perspective? (1)

John Hasler (414242) | more than 4 years ago | (#30698180)

> But a real invisibility cloak has to detect the direction of every photon
> striking it and deliver that proton in the same direction out the exact
> opposite side of the cloak, doesn't it?

And exactly that is theoretically possible with metamaterials. In any case, a cloak could be useful even if it only works over perhaps 120 degrees.

Re:Only works from one perspective? (0)

Anonymous Coward | more than 4 years ago | (#30711412)

Yeah, and a shadow wandering around with no cause wouldn't bring any attention at all....

Re:Only works from one perspective? (2, Informative)

theIsovist (1348209) | more than 4 years ago | (#30698190)

you're missing the point. this is more of a lens. It redirects light around the object. now, how fluidly it does this has yet to be seen, but any light that originates behind the object will be bent in a way that it never strikes the object. I'm not sure how this would look in real life, but given a mathmatically perfect lens, the object would bend all light around it so that it comes out exactly on the other side. In that case, as far as our sense of sight is concerned, the object would not exist

Re:Only works from one perspective? (2, Funny)

mea37 (1201159) | more than 4 years ago | (#30698378)

And as far as it's sense of sight is concerned, the rest of the world would not exist.

Douglas Adams had a jump on this one... "a beast so stupid it believed that if you cannot see it, it cannot see you"

Re:Only works from one perspective? (0)

Anonymous Coward | more than 4 years ago | (#30699026)

Uh.. my cat is *not* stupid. And, he can pick things up (like Kix cereal) with his thumbs!

Re:Only works from one perspective? (1)

Bigjeff5 (1143585) | more than 4 years ago | (#30699054)

And as far as it's sense of sight is concerned, the rest of the world would not exist.

Ever heard of view-holes? We only need about a quarter-inch diameter hole to get a nearly 180 degree field of view. Cameras can do the exact same thing, often times with less.

I don't know if you know this, but it's a lot harder to see a little dot a quarter-inch in diameter floating in space than it is to see a 6' tall person or a 10' by 15' tank, or whatever the hell ends up getting cloaked.

Taking care of visibility out is downright EASY. You simply need a very small (in size) light collector just outside the effect of the light bender.

Duh.

Re:Only works from one perspective? (1)

mea37 (1201159) | more than 4 years ago | (#30723364)

Glad to hear your advanced research is going so well. So you'll be able to move out of your mom's basement soon?

Re:Only works from one perspective? (1)

Yfrwlf (998822) | more than 4 years ago | (#30715860)

I don't care what you say, if you're in bed under your blanket and can't see any boogie monsters, that is the safe zone, by monster law.

OK, commence with the sexual innuendo jokes.

Re:Only works from one perspective? (1)

tmosley (996283) | more than 4 years ago | (#30698874)

They are talking about a material that has a negative refractive index when placed under a magnetic field. If it has a negative refractive index for all wavelengths of visible light, then it IS an invisibility cloak. They aren't talking about transmitting light through the object, as you seem to think, but rather bending light AROUND it, which is possible and does work (at certain wavelengths).

Re:Only works from one perspective? (0)

Anonymous Coward | more than 4 years ago | (#30698876)

Since it works by using a magnetic field to orient the particles, would you not merely have to change the orientation of the magnetic field for it to work for a certain direction? I mean it's far from perfect, but it's a lot more technologically flexible than we've had in the past.

Re:Only works from one perspective? (1)

Zero__Kelvin (151819) | more than 4 years ago | (#30702886)

Wow. Now that is invisible. A picture that generates an HTTP 404 error when you look at it is cool, but of course there is always the danger that someone will just come along and add an "l" at the end of it. (see http://www.moillusions.com/2007/12/julian-beevers-new-3d-sidewalk.html [moillusions.com] , not .htm ).

Disclaimer: I only clicked on it because I thought it said Jullie-Ann Beavers. Needless to say I was rather disappointed after defeating the URL / invisibility mechanism.

Sorry for the lack of photos! (2, Funny)

Anonymous Coward | more than 4 years ago | (#30698138)

We poured the material in a jar so that you could see the effects, but unfortunately we now seem to have misplaced it. We'll update as soon as we found it!

negative index != invisibility (5, Informative)

stevenj (9583) | more than 4 years ago | (#30698168)

All metamaterials are not created equal. A metamaterial is an electromagnetic medium created by a composite of tiny (very subwavelength) constituent structures, put together in such away that longer wavelengths see an "average" material with properties very different from those of the constituents. Usually, the goal is to use resonant effects in the microscopic constituents to make a material that is effectively very different from naturally occuring EM media. But this can be done for many different purposes.

A negative-refractive metamaterial is designed to have an effective "negative" index of refraction, which makes Snell's law (refraction) bend backwards, and can potentially be used for flat-lens near-field imaging, subwavelength imaging (again only in the near field), etcetera. The main practical difficulty here is that the most interesting applications of negative-index materials are in the visible or infrared regime, but negative-index metamaterials rely on metallic constitutents and metals become very lossy at those wavelengths.

Recent "invisibility" cloak proposals are based on the observation that there is a one-to-one mapping between transforming space to "curve around" the object being cloaked and keeping space the same and transforming the materials. So, if you can make materials with certain properties, they could effectively cloak an object by causing all the light rays to curve around the object just as if space were curved. Although this is mathematically quite beautiful, there are many practical obstacles to making this a reality. The proposal is to make the required materials via metamaterials, but these are NOT negative-index metamaterials. The required materials theoretically tend to require some singularities (points where the index blows up or vanishes), and trying to approximate that in practice inevitably involves losses which spoil the cloaking. In general, the bigger the object to be cloaked compared to the wavelength, the smaller the losses have to be, and the narrower the bandwidth is going to be. When you work out the numbers, you see that this is why all the experimental demonstrations of cloaking have only "cloaked" (reduced the scattering crosssection, but not to zero) objects that were a wavelength or two in diameter. Cloaking macroscopic objects at visible wavelengths is a fantasy because the material requirements are insane. The only remotely practical prospects seem to be cloaking objects on the ground (which makes things technically easier because the coordinate transformations are nonsingular) to long-wavelength radiation, e.g. cloaking something against radio waves.

Re:negative index != invisibility (1, Funny)

Anonymous Coward | more than 4 years ago | (#30698370)

All that interesting information, and yet no car analogy. C-

Re:negative index != invisibility (1)

Dalambertian (963810) | more than 4 years ago | (#30698868)

Finally a use for transparent ferro-fluids http://www.youtube.com/watch?v=me5Zzm2TXh4 [youtube.com] ? I wish TFA had a better description of how this is supposed to work, so I will have to resort to some serious hand-waving: It sounds like they are trying to make field-aligned wave guides. This would be similar to the way our magnetosphere moves plasma from the night side to the day side by moving around the Earth's magnetic field, a process that happens whenever the magnetic field of the solar wind points south. The analogy can only be taken so far, but for a plasma the magnetic field is all you need in order to confine the average particle motion to surfaces of equal field line length (assuming no external electric field). To do this for photons, you would need the conducting silver layer to confine the light to parallel surfaces of the magnetic field. If all this were true then I say this is f'n brilliant. If not, well it's plausible enough to make for good science fiction.

Ministry of Magic needs to know. (1)

itsenrique (846636) | more than 4 years ago | (#30698178)

someone get this news to harry potter and friends, unicorn tears are probably more rare than silver.

Quicksilver? (0)

Anonymous Coward | more than 4 years ago | (#30698186)

So next they will come up with a synthetic gland that can be implanted in a person's head..

It's all about Ninja's, DUH! (1)

socz (1057222) | more than 4 years ago | (#30698216)

They gave up on trying to make ninja's of their own (since they can only make cheap imitation knockoff's) so they just said forget the ninja part! Let's just make all of our forces invisible!

Re:It's all about Ninja's, DUH! (0)

Anonymous Coward | more than 4 years ago | (#30699664)

They gave up on trying to make ninja's of their own (since they can only make cheap imitation knockoff's) so they just said forget the ninja part! Let's just make all of our forces invisible!

Why don't you make those apostrophes invisible?

Re:It's all about Ninja's, DUH! (1)

socz (1057222) | more than 4 years ago | (#30849228)

haha yeah sometimes I get confused sorry! When I hit submit I was like DOH#!@^#!@*

Re:It's all about Ninja's, DUH! (0)

Anonymous Coward | more than 4 years ago | (#30703452)

weren't originally ninjas cheap labor (compared to, fielding an army of samurai (drawn from nobility))

Star Wars (1)

fast turtle (1118037) | more than 4 years ago | (#30698278)

"Luke Raised his Macroculars to the sky and watched the Rebel ship be destroyed by the Imperial Star Destroyer"

To me this sounds suspicously like a Oil Filled Variable Focus Lens with higher magnification and image stabilization.

The big question though is this something new?

Re:Star Wars (2, Informative)

jfengel (409917) | more than 4 years ago | (#30698452)

The big question though is this something new?

Well, besides not being fictional, the big idea is that the thing (potentially) has a negative index of refraction, something not even the fictional lenses do.

Negative refraction is useful in making invisibility shields, by directing light completely around object surrounded by it.

This doesn't go nearly that far; it's a step towards a new way of constructing metamaterials with negative indexes. That's important; the "invisibility" stuff is just press-release science because invisibility is far more interesting than magnetically-controlled metamaterials.

Invisibility? (5, Funny)

electricbern (1222632) | more than 4 years ago | (#30698288)

I'll believe it when I see it.

Space Cloak! (0)

Anonymous Coward | more than 4 years ago | (#30698304)

This seems like a great way to hide a satellite, if you can keep the temperature of the fluid regulated. Of course, you can't hide solar panels, so you'll need an internal power source.

Re:Space Cloak! (2, Interesting)

wizardforce (1005805) | more than 4 years ago | (#30698434)

An internal power source must obey the laws of thermodynamics and thus would cause the craft as a whole to be an infrared emitter. We are very good at detecting infrared light which would defeat most cloaking devices including this one.

Re:Space Cloak! (1)

earlymon (1116185) | more than 4 years ago | (#30701456)

An internal power source must obey the laws of thermodynamics and thus would cause the craft as a whole to be an infrared emitter.

Now you're just being silly.

As IR is still light, put a second cloak inside the first cloak, but this time FACING the satellite, so the satellite can't see the earth either.

Now - that surely sounds like fractured logic - until you add a third cloak so the earth can't see that the satellite's not seeing the earth.

Wait - can you tell it's beer-thirty on Friday???

possible solution (0)

Anonymous Coward | more than 4 years ago | (#30704274)

send all the waste heat in the direction away from earth. that way it may be possible to make the side facing earth very close to invisible.

It WOULD work IF (Do that and you'll go BLIND) (5, Interesting)

mrnick (108356) | more than 4 years ago | (#30698558)

It would work "optically" if the Invisibility Cloak was made out of vegetable oil and you were made of Pyrex...

Vegetable oil and Pyrex has the same refractive index...

* put a small Pyrex jar into a larger one and then fill the smaller (inner) jar with vegetable oil and once it's full continue to fill the larger one with the overflow. The smaller (inner) jar will become invisible, to the naked eye.

On a more serious note this seems to be a big problem with all invisibility cloaks, of non supernatural origin (calm down HP fans), and that is they are all based upon modifying materials refractive index and thus bending the light around the object you want to hide.

That all sounds good but if you could do this to hide an object; If that object were a person since light doesn't hit them, or their eyes, not only would they be invisible but they would also be blind. I think most people asking Santa for a invisibility cloak would like to actually see what's in the girls locker room right?

A perfect invisibility cloak would change the person wearing it, along with the cloak, to a refractive index of air but again, they would be perfectly blinded by the process. In the case of RI = air then the light would go straight through them, included their eyes. So you either bend the light or have it go through your eyes and either way your in the dark.

I guess you could hide everything but your pupils, but in my book you wouldn't be invisible then, floating eyeball freak!

LOL

Nick Powers

Re:It WOULD work IF (Do that and you'll go BLIND) (1)

Judinous (1093945) | more than 4 years ago | (#30698834)

One word: echolocation.

Re:It WOULD work IF (Do that and you'll go BLIND) (1)

PRMan (959735) | more than 4 years ago | (#30698946)

And this is exactly why a proper invisibility cloak must be computer controlled with millions of dots of resolution interspersed with millions of cameras. The idea is that, like a chameleon, you change to look like your background. With you inside, the cameras can also give you a view of your surroundings.

And yes, it would still give off a heat signature, but most people aren't walking around with night vision goggles all the time.

no please read up on the subject (0)

Anonymous Coward | more than 4 years ago | (#30700966)

http://en.wikipedia.org/wiki/Victor_Veselago
for a start
then
http://en.wikipedia.org/wiki/John_Pendry
then find copies of their papers. the veselago paper is a scan cause its reasonably old. the pendry paper basically shows that if you take a slab of material with negative permeability and permittivity then you get a perfect lens.

later people showed that you could have external neg refractive index cloaks that would compensate for the optical influence of the object to be cloaked.

start with vesalago.

Re:It WOULD work IF (Do that and you'll go BLIND) (1)

smaddox (928261) | more than 4 years ago | (#30698950)

An invisibility cloak, as in the sort used by harry potter, is not possible with a passive device. This is fairly obvious since you can't see light and yet be transparent to it at the same time.

However, there is no theoretical limit if the device is active. A simple example would be a flat panel display with a camera on the back. If you track the position of the observer, you can create a very convincing "invisibility" effect.

More interestingly, it may one day be possible to use active metamaterials to produce a similar effect. However, such a device would not be used for cloaking people, but rather for cloaking planes to Radar (for example).

Re:It WOULD work IF (Do that and you'll go BLIND) (0)

Anonymous Coward | more than 4 years ago | (#30699692)

There is also the consideration that a pinhole (or a few) may be enough light to see well enough and still be close enough to invisibility for the application. (As others have noted, there are ways to sense an invisible person using this technology, they just involve more than a normal pair of eyes or camera.)

Re:It WOULD work IF (Do that and you'll go BLIND) (1, Funny)

Anonymous Coward | more than 4 years ago | (#30699166)

Google up "pinhole camera" or "camera obscura" and you will see that we've had the technology to solve that part of the problem for close to a thousand years.

Re:It WOULD work IF (Do that and you'll go BLIND) (1)

Bigjeff5 (1143585) | more than 4 years ago | (#30700166)

Why mod this funny? It's insightful!

Granted, as soon as you poke a camera out of the field it isn't 100% invisible, it's only 99.99% (or more) invisible. Still that's pretty damn good, do you know how hard it would be to notice a tiny dot floating around in space?

Re:It WOULD work IF (Do that and you'll go BLIND) (0)

Anonymous Coward | more than 4 years ago | (#30699360)

Well, actually, couldn't you have sensors for things other than light underneath the cloak?

You could use it to, uh, smell the girl's locker room?

NO. please read up on the subject (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#30700836)

http://en.wikipedia.org/wiki/Victor_Veselago
for a start
then
http://en.wikipedia.org/wiki/John_Pendry
then find copies of their papers. the veselago paper is a scan cause its reasonably old. the pendry paper basically shows that if you take a slab of material with negative permeability and permittivity then you get a perfect lens.

later people showed that you could have external neg refractive index cloaks that would compensate for the optical influence of the object to be cloaked.

but start with vesalago.

Battle of New Orleans (1)

snspdaarf (1314399) | more than 4 years ago | (#30701178)

Ol' Hick'ry said "You kin take 'em by surprise,
If you just fire yer musket at the pupils of their eyes"

Forget cloaking and make a photonic computer. (0)

Anonymous Coward | more than 4 years ago | (#30698900)

If you can configure the optical properties of this fluid on the fly, build an optical processor from it.

One thing I always wondered about (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#30699392)

with an invisibilty clock, how do you see out. If your eyes are absorbing light then you would be able to be detected.

"Makers of first invisibility cloak sued... (1)

Tybalt_Capulet (1400481) | more than 4 years ago | (#30699582)

by the joint companies Scholastic Books and Warner Brothers Films due to copyright infringement over the J.K. Rowling works Harry Potter."

Better Applications (0)

Anonymous Coward | more than 4 years ago | (#30700544)

I don't see the use in bothering to create such a device. I'm sure in military, magician and certain social circles this could have great value.

However, it seems like such technology... if possible... would be valuable in all kinds of truly useful application that could truly benefit society.

For example: wouldn't bending full spectrum light through a liquid medium controlled by an electric field be highly useful in the solar industry? I mean the cost of mirror alignment and replacement is a great cost factor in these systems.

Now I have no idea if this is really a useful application of this sort of technology... I'm just thinking aloud. But "Invisibilily Device"... come on, DON'T WASTE MY TIME. Even if it is possible, that would be a less important application for our sustained future. The very fact that this is in the "invisibility device" categories leads me to believe that such technology is not even close to been shown to be truly possible. IMO: This is fluff.

Alternatively, the researchers know that the only way to get their science research in the public eye is to attach it to some "wow" factor. Knowing full well that the true applications will likely be more useful (but less "wowful") in the real world.

I subscribe to the "I'll believe it when I see it" camp.

lasers (2, Interesting)

lq_x_pl (822011) | more than 4 years ago | (#30701042)

Anyone know how this material responds to lasers? If it doesn't break, it might be a useful way of preventing resources on the ground from being "painted" by a laser (and subsequently bombed).

chinese stealth armour? (1)

Eunuchswear (210685) | more than 4 years ago | (#30706244)

or just a stealth boy?

Vaporware? (1)

VeNoM0619 (1058216) | more than 4 years ago | (#30739912)

So when does this turn into vaporware...?
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