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How To Cloak Objects At a Distance

samzenpus posted more than 5 years ago | from the can-you-see-me-now dept.

Science 136

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."

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136 comments

Yawn (0)

rodrigoandrade (713371) | more than 5 years ago | (#25659663)

Wake me up when we can get stuff cloaked like Master Chief or the Predator.

Re:Yawn (5, Funny)

noidentity (188756) | more than 5 years ago | (#25659675)

You'll know when cloaking is really working when the monthly dupe of "cloaking, this time for real" stops showing up here.

Re:Yawn (4, Funny)

discord5 (798235) | more than 5 years ago | (#25659727)

You'll know when cloaking is really working when the monthly dupe of "cloaking, this time for real" stops showing up here.

Because they managed to cloak the article?

Re:Yawn (4, Funny)

noidentity (188756) | more than 5 years ago | (#25660763)

And here I always thought that explaining a joke was sure to ruin it.

Re:Yawn (1)

theaveng (1243528) | more than 5 years ago | (#25660813)

All invisibility cloaks to date work by hiding an object embedded inside them.

I had no idea we had working cloaks! Cool. Having an invisibility cloak would make raiding the Sorority Girls' dorm so much easier for the Engineering house. Where can I get one? :-)

Re:Yawn (1)

MikeDirnt69 (1105185) | more than 5 years ago | (#25661757)

I can sell you one. Would you transfer the money first? It's guaranteed!

Re:Yawn (1)

noidentity (188756) | more than 5 years ago | (#25661983)

I can sell you one. Would you transfer the money first? It's guaranteed!

The money will disappear, that's for sure. So I guess you really do have one, in a sense.

Re:Yawn (2, Insightful)

jebrew (1101907) | more than 5 years ago | (#25662541)

I dunno, they've got a good point. If no light is getting in to the object being cloaked, then it's not just invisible, it's blind...so while you wouldn't see much in the Sorority Girls' dorm, you could have loads of laughs feeling up anything that crossed your path.

Re:Yawn (1)

Hognoxious (631665) | more than 5 years ago | (#25662783)

To be cloaked it doesn't need to stop light getting to it. It just needs to stop it getting back to the observer. But don't stand in front of a white surface.

Re:Yawn (1)

theaveng (1243528) | more than 5 years ago | (#25664695)

Yes like Harry Potter's cloak. He can see through the cloth, but no one can see him.

Re:Yawn (1, Funny)

Anonymous Coward | more than 5 years ago | (#25665063)

Wow, are we really citing Harry Potter?

Re:Yawn (2, Funny)

fugue (4373) | more than 5 years ago | (#25663195)

This, then, shall be your test. To the engineer who can build her own invisibility cloak, I say that she is worthy of raiding the Sorority Girls' dorm. To all those who dare not face the challenge, their punishment shall be downloading pr0n.

Re:Yawn (2, Funny)

Anonimouse (934959) | more than 5 years ago | (#25659723)

Wake me up when we can get into the ladies changing rooms without getting bitch slapped.

50% of the population does it all the time (5, Funny)

SmallFurryCreature (593017) | more than 5 years ago | (#25659963)

How hard can it be if even girls manage it?

Re:Yawn (1)

Zerth (26112) | more than 5 years ago | (#25660007)

Get implants and shave.

Re:Yawn (1)

UncleTogie (1004853) | more than 5 years ago | (#25664193)

Wake me up when we can get into the ladies changing rooms without getting bitch slapped.

Easy! These guys [wikipedia.org] pulled it off years ago...

Re:Yawn (1)

kingsteve612 (1241114) | more than 5 years ago | (#25661917)

yeah dude. that would be sick.

I can do this (0, Redundant)

mcfatboy93 (1363705) | more than 5 years ago | (#25659695)

so basicly what this is saying is that you can't see me if i hold up a sheet that is the same color as the wall

Re:I can do this (1)

snowraver1 (1052510) | more than 5 years ago | (#25661617)

No, no, no! It's saying that you can't be seen if someone else holds up a sheet that is the same color as the wall.

Re:I can do this (2, Interesting)

lysergic.acid (845423) | more than 5 years ago | (#25662495)

no, because then you're behind/inside the cloak and your visibility in the cloaked direction is zero. you're not unbending the light with a complementary image. if the light source is behind you, you'd just look like a jackass holding up a bed sheet.

the method proposed in the article is to hide objects outside (hence, "How to Cloak Objects At a Distance") of a cloak using a complementary material. no materials have yet been developed to do this.

it doesn't even necessarily have to be a physical material. if you can use lasers or an EM field to bend(or unbend) light back to its original state, then you can simulate a virtual complementary material. you'd still need to determine the optical properties of the object that you want to cloak to create the complementary image, but you could theoretically create a mobile/non-stationary cloaking device this way.

Re:I can do this (1)

jfeldredge (1008563) | more than 5 years ago | (#25662931)

You would still be cloaked only from one side, and visible from other directions. Also, you wouldn't be able to see in the direction that you are cloaked from; if all of the light from that particular angle is passing around you, rather than reaching you, you would see the reverse side of the cloaking device/field as black. So, this technique would work if you were trying to hide from a sensor or observer at a particular angle to you, but wouldn't be particularly effective against a web of sensors that are sharing their results.

Wow smart scientists... (4, Funny)

Lumpy (12016) | more than 5 years ago | (#25659705)

"The trick is to make the cloaking material with optical properties that are exactly complementary to the space outside them. "

So if you are hiding a tank in the desert, paint it desert colors?

Oh wait more complex... desert != shiny...

use flat paint.

got it!

Re:Wow smart scientists... (5, Funny)

discord5 (798235) | more than 5 years ago | (#25659793)

So if you are hiding a tank in the desert, paint it desert colors?

We've actually gone one step further. We've actually built an entire tank made out of sand. Our prototype required very little materials other than that: a bucket, a shovel and a beach.

It's still a prototype though since it breaks easily, but it does blend in with its surroundings, and it has been proven combat worthy by having our troops stomp over sandcastles.

Re:Wow smart scientists... (1)

Arimus (198136) | more than 5 years ago | (#25659897)

It's still a prototype though since it breaks easily,

What do you mean prototype? that sounds almost ready for serious use - just look at most tanks ;)

Re:Wow smart scientists... (4, Funny)

Cthefuture (665326) | more than 5 years ago | (#25661763)

Heh, you know to this day I'm still pissed about something that happened when I was in 2nd grade. We were doing some kind of group work thing and I got was this multiple choice question about what a telescope could be made out of. One of the possible answers was sand. I instantly came up with the design in my head. The question wasn't very specific so I wasn't sure if I would need to melt the sand to form the lenses but I knew I could use a glue/sand mixture for the body (shaped by a mold while it hardened).

Naturally I got the answer "wrong" and nobody would listen to me. That episode basically represents how my entire life has gone when dealing with other people...

Re:Wow smart scientists... (3, Funny)

psydeshow (154300) | more than 5 years ago | (#25664533)

Otherwise known as "Too smart for your own good." That happened to me all the time while I was growing up.

Now people just think I'm a crank when I make non-linear associations like that.

Re:Wow smart scientists... (1)

Artuir (1226648) | more than 5 years ago | (#25665121)

People mod that up funny, but it's actually insightful as to how the school system doesn't work for everyone, and how thinking outside of the box is so frowned upon when everyone should do their utmost to encourage it.

Re:Wow smart scientists... (4, Insightful)

Emb3rz (1210286) | more than 5 years ago | (#25659821)

Think about it in terms of bitmasks...

Background   = 00110000
UncloakedObj = 11100000
CloakedObj   = 00001100

CloakShows   = 11110000

Re:Wow smart scientists... (5, Informative)

MetalPhalanx (1044938) | more than 5 years ago | (#25660211)

Only on /. would someone try to explain such science in terms of bitmasks. :)

Re:Wow smart scientists... (4, Funny)

IchNiSan (526249) | more than 5 years ago | (#25661741)

Ok, just think of this in terms of a car ...

Re:Wow smart scientists... (1)

Tetsujin (103070) | more than 5 years ago | (#25665133)

Ok, just think of this in terms of a car ...

Thanks! That made it much clearer!

Re:Wow smart scientists... (1)

d0n0vAn (1382471) | more than 5 years ago | (#25661837)

I'm not the brightest bulb in the box and I did have to google it, but now I see what you did there. 10/10

Re:Wow smart scientists... (2, Insightful)

db10 (740174) | more than 5 years ago | (#25661959)

It's not the masking that's the problem, it's filling in the mask dynamically.

Re:Wow smart scientists... (0)

Anonymous Coward | more than 5 years ago | (#25663771)

I must be dumb, but can someone explains the parent's comment?

thx
A.C

Re:Wow smart scientists... (1)

slas6654 (996022) | more than 5 years ago | (#25663855)

Now to get started painting everything black and white.

Re:Wow smart scientists... (0)

Anonymous Coward | more than 5 years ago | (#25660387)

This is old news. The master illusionist, Sir Jasper Maskelyne, was using this technique in Egypt's Western Desert for the British Army in 1940-42. It is described clearly in his autobiography. Have a nice day!

New improved goatse (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#25659717)

Re:New improved goatse (1)

Emperor Zombie (1082033) | more than 5 years ago | (#25664131)

If this technology ever becomes viable, I know what we should cloak first.

Firing while cloaked (5, Funny)

vvaduva (859950) | more than 5 years ago | (#25659747)

The better question is, can they fire while cloaked? I hear the Klingons made substantial advances in that area.

Re:Firing while cloaked (1)

ub3r n3u7r4l1st (1388939) | more than 5 years ago | (#25659997)

Mmm not sure. I know Harry Potter couldn't.

Re:Firing while cloaked (0)

Anonymous Coward | more than 5 years ago | (#25660049)

There was only one prototype, and Kirk blew it up, along with the Shakespearean General Chang.

And it apparently only worked because it ran off of fossil fuels or something. How 20th century.

Not a dupe, but... (4, Funny)

AltGrendel (175092) | more than 5 years ago | (#25659751)

...this reminds me of that "X-Files" article from yesterday.

"Gee, if we had enough money, we could make your troops invisible, Mr. General Sir."

Re:Not a dupe, but... (0)

Anonymous Coward | more than 5 years ago | (#25660131)

I dont know whether to mod that insightful or funny... So, instead I will give you this meaningless reply :)

No. This one has an actual demonstation (0)

Anonymous Coward | more than 5 years ago | (#25660657)

Cloaking demonstration [youtube.com]

nowhere left to hide (-1, Troll)

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Small...Far Away. (1)

ciderVisor (1318765) | more than 5 years ago | (#25659857)

Dougal, this cow is small.

Those ones are far away.

Small...far away.



"That's nearly as mad as that thing you told me about the loaves and the fishes."

Re:Small...Far Away. (2, Insightful)

andy19 (1250844) | more than 5 years ago | (#25660071)

As much as I love the Father Ted reference, that really doesn't have anything to do with this article.

wait (5, Funny)

jav1231 (539129) | more than 5 years ago | (#25659861)

Wouldn't pr0n constitute a complimentary image? Cuz I gotta tell ya with the right pr0n nearly everything around it disappears.

Re:wait (0)

Anonymous Coward | more than 5 years ago | (#25660739)

Speaking of pr0n... Can this device make only the clothes of someone invisible ?

Jeez (4, Funny)

Konster (252488) | more than 5 years ago | (#25659875)

Everyone knows that a tachyon sub-space burst from the main deflector dish invariates the sublimated inverse proportional fields that all cloaking devices use.

Phase the array with multi-numinal values and any cloak in the perimeter will be dropped due to subversive nominal decay but only if you attune your tertiary sensing systems to compensate for the quadralinear flux.

This is all so simple, and I have to wonder about the credentials of /. editors that would post such elementary issues on this website.

I mean really, this is first trimester stuff that any recruit can do off the tops of their heads.

Re:Jeez (1)

jez9999 (618189) | more than 5 years ago | (#25660785)

... and, Mr. Data.

Yes, sir? ... Nicely done!!!

Go back to Academy, Ensign. (1)

argent (18001) | more than 5 years ago | (#25661053)

That's the oldest trick in the book, and it only works against objects that are polaron neutral against the subspace background. And since most variations of phase-harmonic shields break polaron symmetry any military warp-capable ship is immune.

The next step... (1)

MadDogX (1365487) | more than 5 years ago | (#25659909)

So we have the technology for an invisibility cloak. Now I just need an unbeatable wand and a funky "I see dead people" ring and I can be master of death. Suck on that, Voldemort!

Fair in war (0)

Anonymous Coward | more than 5 years ago | (#25659965)

Cloak objects at a distance ?

Why do we need this this ?
    Weapons of war can already kill at range greater than the enemy and those firing it can see ,
  ans so they have since World war One.

What do we gain ?
True Invisibly is a great danger , Its use is only bad and or covert.
When used by the police , it only makes any government a bigger Polizeistaat (police state )
When used by the military we can already kill covertly.
So what good is it?

How to not be seen at a distance, low-tech style.. (4, Funny)

Notquitecajun (1073646) | more than 5 years ago | (#25659977)

Ummm...howzabout just hiding behind a tree or ducking...

Re:How to not be seen at a distance, low-tech styl (4, Funny)

dkleinsc (563838) | more than 5 years ago | (#25660069)

Notquitecajun, will you stand up please. (gunshot)

This demonstrates the value of not being seen.

Re:How to not be seen at a distance, low-tech styl (0)

Anonymous Coward | more than 5 years ago | (#25660213)

Monty Python, nice. Can't remember the name of the skit though.

Skit title (0)

Anonymous Coward | more than 5 years ago | (#25661301)

The name of the skit is "No. 42 How not to be seen".

http://www.youtube.com/watch?v=I4ZnGprplKU

Re:How to not be seen at a distance, low-tech styl (1)

db10 (740174) | more than 5 years ago | (#25662027)

well I manage to cloak myself by securing a towel around my head... I figure if I can't see you, then surely you can't see me.

Re:How to not be seen at a distance, low-tech styl (0)

Anonymous Coward | more than 5 years ago | (#25660111)

Why not duck or hide ?
  Because a 50 caliber rifle can penetrate a 15 inch thick tree at thousands of Yards as if it were toilet paper , and the speed of the bullet such that before You, the one firing it hears the crack of the gun , the enemy or tree has about a 5 - 6 inch gaping hole in it ..
Reason enough ?
   

Re:How to not be seen at a distance, low-tech styl (3, Interesting)

Notquitecajun (1073646) | more than 5 years ago | (#25660709)

I'll go you one better - over in the Middle East, there were apparently some insurgents/terrorists/whoever using the tried-and-true method of hiding in a sandstorm before attacking or while attacking. It worked well in the good old days, but we now have these things called satellites and night-vision and infrared and technology, where they're pretty much sitting ducks now.

Re:How to not be seen at a distance, low-tech styl (2, Interesting)

MartinSchou (1360093) | more than 5 years ago | (#25664059)

Well, if they're hiding in the sandstorm BEFORE the attack, sure.

But during? You'll be hard pressed to find a radio wave length that'll cut through what is essentially a huge but very fluffy stone and NOT cut through humans (tiny bit of water in the middle). Infrared will be blurred out. Radar will too.

What kind of advances have the military conjured into being that'll see through a sandstorm and tell you what's inside it (outside of lots and lots and lots of sand)?

Re:How to not be seen at a distance, low-tech styl (0)

Anonymous Coward | more than 5 years ago | (#25664701)

Parabola!

Re:How to not be seen at a distance, low-tech styl (4, Informative)

shawn(at)fsu (447153) | more than 5 years ago | (#25663391)

I'd like to see your source on that one, Assuming that sound can't move through the rest of the rifle(for sake of discussion) and will only escape out of the muzzle the shooters ear is about 1 meter away form the source. The Barrett M82 (using .50 BMG round) has a max effective range of 6800m with a muzzle velocity of 853 m/s. That means that it will take that round 7.79 seconds to go the max distance or 2.16 seconds to go the effective range of 1850 meters.

The speed of sound is 340.29m/s, so for the sound of the gun shot to go from the muzzle to the shooters ear 1 meter away will take apx 0.0029 seconds.
At 853 m/s the round will have only traveled 2.47 meters away from the muzzle.

Provided the target is less than 2.47 meters away then yes the will have a whole in them before you the shooter hears teh shot, but you said thousands of yards, which as we proved is just wrong. Now had you said that you the target will have a whole in you before you the target even hears the report then yes you would be right.

Oh and you totally misused the joke anyway of th GP. It was a Monty Python sketch. /All figures from GIS and wikipedia) //Math could be wrong, please correct me if I'm wrong

Re:How to not be seen at a distance, low-tech styl (0)

Anonymous Coward | more than 5 years ago | (#25664389)

Well, for one, the effective range of a .50 cal sniper rifle is closer to 2000m than it is to 7000m. 7000m is basically the ballistic trajectory of a 45 degree shot.

Re:How to not be seen at a distance, low-tech styl (1)

chord.wav (599850) | more than 5 years ago | (#25664859)

I was thinking more like going one step further past the point where you are a tiny on the horizon to your enemy's eyes

Only transulcent objects? (1)

Timmmm (636430) | more than 5 years ago | (#25659987)

This must only work with translucent objects. The other method works with any object.

It's trap (1)

ZeroExistenZ (721849) | more than 5 years ago | (#25660013)

This "cloak"-technology is just a re-adjustment of your mental reference framework:

Soon, you'll get these kindof presentations:
"This! is the best thing ever since the previous thing that was the best thing ever!" "Can I see?"
"It's right here, it's cloaked.. You can see it but you cannot perceive it. But believe me, it's there."
"If it's invisible, it must be good! *throws monnies*"

If you give it some thought (5, Insightful)

Dunbal (464142) | more than 5 years ago | (#25660027)

This technology, if adopted by the military, will probably only be useful against civilians. Against another sophisticated military there will always be a way to detect what you're trying to hide through other means than visible light - magnetism/alterations in the earth's magnetic field (in the case of big chunks of metal, heat), RF emissions, overhead imaging, radar, sonar, etc.

You won't be able to hide your tank like this, but the small laser turrets to keep the neighbor's cat off the lawn might work... now if only those sharks would stop swimming.

Re:If you give it some thought (0)

Anonymous Coward | more than 5 years ago | (#25660845)

This technology, if adopted by the military, will probably only be useful against civilians.

Well... sort of. I suppose they have in mind insurgents, irregulars, rebels, rioters, militias (both well regulated and not so well regulated) and their non-combatant sympathizers, civilians who would spy on military.

Also, this will probably have its first use in hiding public surveillance cameras and other surveillance devices - what you don't know, you can't complain against.

Re:If you give it some thought (2, Interesting)

Yvanhoe (564877) | more than 5 years ago | (#25660899)

That is why it is important to maintain sophisticated technology in the civil society.

Re:If you give it some thought (4, Insightful)

JustinOpinion (1246824) | more than 5 years ago | (#25661017)

I'm not so sure about that. I mean, the military currently uses a whole bunch of stealth technology against their enemies: everything from simple paint color and camouflage, to radar-reflective stealth paint or ultra-quiet engines for submarines. None of these are perfect, but all are useful.

You may not be able to make yourself 100% invisible to an enemy that has good tech, but as long as you can give yourself an advantage in hiding, it's worth using. The "advantage" could be increased survival (enemy hit accuracy is reduced), better range (you can get closer before being detected), or maybe just the cost to the enemy for them to launch all the overhead imaging and use all magnetic field sensing equipment you just mentioned.

If cloaking became viable, it would definitely be used by the military against other high-tech enemies. In battle, every advantage counts.

Re:If you give it some thought (3, Insightful)

Culture20 (968837) | more than 5 years ago | (#25661059)

This technology, if adopted by the military, will probably only be useful against civilians.

Or unsophisticated military. Against other sophisticated military, it's good to have the tech first because that allows research into counter-tech sooner. One way to beat the enemy is to force them to spend too much in resources keeping a stalemate.

The key point (3, Interesting)

brunes69 (86786) | more than 5 years ago | (#25661905)

... in your argument is "against another sophisticated military".

However this is rarely the case. Nowadays most engagements the US Military is involved in are against people with little more than 25-50 year old weapons. The problem the US Military has is the on the ground war against these kinds of insurgents - this tech. would be invaluable against them, you could approach a camp on foot without fear of being seen.

Re:If you give it some thought (3, Insightful)

dreamchaser (49529) | more than 5 years ago | (#25664945)

You obviously haven't given it much thought. If your logic held true, there would also have been no reason to develop stealth technology for our aircraft. As someone else astutely pointed out in response to you, every advantage helps. There would be many, many applications for 'cloaking' technology against even high tech militaries.

Of course, it's fashionable around here to say will really only be useful when used against civilians.

Ho8o (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25660029)

culture of abuse a sad world. At is the ultimate Niggers everywhere Won't vote in EFnet, and aaply move forward,

Misplaced effort. (0)

gpn (991395) | more than 5 years ago | (#25660035)

They should be working on the SEP field. Hitchikers guide reference: "The technology required to actually make something invisible is so complex and unreliable that it isn't worth the bother. The Somebody Else's Problem field is much simpler and more effective, and can be run for over a hundred years on a single torch battery. This is because it relies on people's natural predisposition not to see anything they don't want to, weren't expecting, or can't explain."

Re:Misplaced effort. (2, Funny)

N Monkey (313423) | more than 5 years ago | (#25660303)

They should be working on the SEP field.

Hitchikers guide reference:

"The technology required to actually make something invisible is so complex and unreliable that it isn't worth the bother. The Somebody Else's Problem field is much simpler and more effective, and can be run for over a hundred years on a single torch battery. This is because it relies on people's natural predisposition not to see anything they don't want to, weren't expecting, or can't explain."

You don't even need a battery. Just build it to look like a sink full of dirty dishes in a student household and no one will see it.

Seems limited (1)

Chthonic Rabbit (1117475) | more than 5 years ago | (#25660075)

Wouldn't this method limit the cloaking mechanism to only work from one viewing angle? It seems to me the cloak would need to have hundreds of complementary images embedded in it to prevent someone from seeing it who took a step to the side. That, however, causes the problem of the complementary images distorting areas around the cloaked item, therefore making the cloaked item even more obvious. Is there something I'm missing?

I just need an old-kind Invisibility Cloak (1)

BhaKi (1316335) | more than 5 years ago | (#25660091)

All invisibility cloaks to date work by hiding an object embedded inside them.

This conventional kind is enough for me. Where can I get one?

Re:I just need an old-kind Invisibility Cloak (2, Funny)

Anonymous Coward | more than 5 years ago | (#25660339)

You do realize you will be blind, right?

Unless you poke some holes in your cloak, and then people will just see eyes floating in the air.

Actually, that seems like a fantastic idea.
Sign me up!

Re:I just need an old-kind Invisibility Cloak (3, Funny)

stranger_to_himself (1132241) | more than 5 years ago | (#25663941)

You do realize you will be blind, right?

Unless you poke some holes in your cloak, and then people will just see eyes floating in the air.

Actually, that seems like a fantastic idea. Sign me up!

Okay so that's one invisibility cloak for...Mr Anonymous Coward.

At a distance? (1)

Quantos (1327889) | more than 5 years ago | (#25660231)

In TFA it admits that the solution would only be 2D and on a single frequency. This leaves me with a few questions.

1. Is the "cloak" effectiveness reduced as the observer gets closer to the object being cloaked?
2. How would they overlay the new image of the item being cloaked, would they use some type of projected hologram, or another physical system - such as attaching the image to the object?

The fast show (2, Funny)

Anonymous Coward | more than 5 years ago | (#25660243)

I'm sure that "The Fast Show" covered this last century...
  • You aint seen me, right?
  • I'll get my cloak.

Shoot (1)

indros (211103) | more than 5 years ago | (#25660279)

I've been doing this for a long time. I simply hold my hand in front of my eyes. Viola! Object remotely cloaked.

Re:Shoot (1)

Alpha Whisky (1264174) | more than 5 years ago | (#25660503)

We've had a hands free version for years, it's called a blindfold. It does kinda require the co-operation of whoever you're trying to cloak things from though.

mo3 0p (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#25660355)

So, in summary... (2, Funny)

stoofa (524247) | more than 5 years ago | (#25660397)

Scientists: "We've made an invisibility cloak that will make your soldiers vanish!"
General: "That's amazing, let's try these out."
Scientists: "Right, Here is one you can try, but if you want more then we need money... a lot of money."
General: "Sorry, the deals off, the soldiers say they can't see out of it when they're inside it."
Scientists: "Give us a few minutes."
[Obligatory view of shed with hammering and sawing noises]
Scientists: "Okay, how about your troops just hide behind it?"

Big-ass photo... (1, Troll)

flyingfsck (986395) | more than 5 years ago | (#25660511)

So, in plain English, they take a big photo of the background, put it in front of the object and make the object disappear from view. How incredibly ingenious.

Re:Big-ass photo... (4, Funny)

Comboman (895500) | more than 5 years ago | (#25660663)

Wile E. Coyote claims prior art.

Re:Big-ass photo... (0)

Anonymous Coward | more than 5 years ago | (#25661875)

Really?
 
I read it as taking a picture of a tank, then covering it in a cloth with the embedded NEGATIVE of that photo.
 
If I understand how light works, though (from my GCSE Physics), wouldn't this just create a black area? All light absorbed etc.
 
Because nobody is going to notice a big, black tank-shaped object heading towards them at 40mph, barrel rotating towards them.

Re:Big-ass photo... (3, Interesting)

Keramos (1263560) | more than 5 years ago | (#25661979)

Well, no, actually they take a photo of the subject, make a sort of translucent negative, and put it in front of the object and make the object disappear from view. Slightly more ingenious because the background can change.

Not sure how they handle the "light behind the 'cloaked object' isn't shining through it" scenario. Presumably you could bend the light around the object and back into it's orignal path - but that's the 'embedded cloaking device' as far as I can tell.

David Copperfield... (1)

afranke (1400099) | more than 5 years ago | (#25661131)

... has been doing this for years.

What about a pointed stick? (0)

Anonymous Coward | more than 5 years ago | (#25661603)

Say someone were to attack you with a banana? Could the cloak protect you?

Somebody Else's Problem (1)

Dteyn47 (1401587) | more than 5 years ago | (#25662183)

I remember reading about this somewhere, I think it's called an SEP Field... "An SEP is something we can't see, or don't see, or our brain doesn't let us see, because we think that it's somebody else's problem.... The brain just edits it out, it's like a blind spot. If you look at it directly you won't see it unless you know precisely what it is. Your only hope is to catch it by surprise out of the corner of your eye." -- Douglas Adams, HHGTG. In that series, a strange object can be effectively hidden from view while out in plain sight, by an "SEP field", which "relies on people's natural predisposition not to see anything they don't want to, weren't expecting, or can't explain."

Didn't RTFM but... (1)

russotto (537200) | more than 5 years ago | (#25662885)

seems to me that having a cloak showing a "complementary object" is only going to work if the original object doesn't destroy information about the background. If it does, the object is going to show via the distortion of the background.

is it two way or one way? (0)

Anonymous Coward | more than 5 years ago | (#25663031)

wouldn't this effectively be "if i can't see you than you can't see me"... meaning that you could stand behind the cloak, but then also anything on the other side of the cloak would also be ... cloaked.

wrong road (3, Funny)

Patrik_AKA_RedX (624423) | more than 5 years ago | (#25663275)

Scientists are looking in the wrong direction in this matter. Like in so many other breakthroughs, they just have to watch how nature does it. What in nature can be totaly invisble without any kind of complex technology or huge power consumption? Easy: keys.

As long as ... (1)

PPH (736903) | more than 5 years ago | (#25664289)

... I can still uncloak them in my mind.

Article Summary (1)

Greyfox (87712) | more than 5 years ago | (#25664611)

1) Assume a cloaking material with optical properties that are exactly complementary to the space outside them.

2) Become invisible using that material.

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