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A Step Towards an Invisibility Cloak

kdawson posted more than 7 years ago | from the who-goes-there dept.

Science 172

An anonymous reader alerts us to work out of Purdue University in Indiana, where researchers have produced a design for a method of cloaking objects of any shape and size at a single wavelength of visible light. The math for such an invisibility effect was worked out last year at Duke and in the UK, but the new work, to be published in Nature Photonics this month, is the first practical design. The lead researcher, Vladimir Shalaev, notes that even though the current design works only at a single wavelength, and so would not convey true invisibility, it could still be useful — against, for example, night-vision goggles or laser target designators. Shalaev calls the technical challenge of producing an all-wavelengths cloak "doable in principle."

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Attn. Slashdot: (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18652407)

Q: Why does 'Open Source' software suck so bad?
A: Because the programmers can't see the screen [ukdirtypanties.com]

lol

Typical Linux User. [ukdirtypanties.com]

Re:Attn. Slashdot: (0)

Anonymous Coward | more than 7 years ago | (#18652653)

I have nothing against ACs, but I'm sick of this shite. I've set my troll modifier to -6 why isn't it working?

Re:Attn. Slashdot: (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18652743)

I had the same problem, before I checked the FAQ:
http://slashdot.org/faq/UI.shtml#ui600 [ukdirtypanties.com]

Re:Attn. Slashdot: (0)

Anonymous Coward | more than 7 years ago | (#18653077)

Ok that was funny, but I didn't click on it. I still want your crap off this page. You're somewhat talented and could be funny (2nd post was funny, content still offensive), but ultimately when I'm at work and I click on this shit I'd really just like to see you swallowing a handful of razorblades.

Re:Attn. Slashdot: (1)

Anonymous Coward | more than 7 years ago | (#18652919)

I've set mine to +5.... I know its kinda messed up. but some times people wrongly get modded troll.

But this type of stuff has to go. what type of low life has nothing better to do then refresh the front page for slashdot every minute to see if they can get the first post about some fucked up stuff.

There needs to be a report abuse button to have people like the sick fuck in the above post banned from slashdot.

Re:Attn. Slashdot: (3, Funny)

Anonymous Coward | more than 7 years ago | (#18653149)

that's why I responded. /. is a great site for professionals (with or without our flaws), great interviews, direct link to Intel and of course goatse I really don't understand. report abuse would be great so this shite could be deleted.

Re:Attn. Slashdot: (1)

WrongSizeGlass (838941) | more than 7 years ago | (#18654021)

I've set my troll modifier to -6 why isn't it working?
Perhaps your invisibility cloak is draining your power?


warning:The above content tests positive for sarcasm and/or is a failed attempt at humor and should be taken with a pound of salt.

A little note about free speech (0)

Anonymous Coward | more than 7 years ago | (#18653199)

I am not the troll who posted the garbage, but who cares? it is a troll. A troll is supposed to invoke a response. If you are that weak minded to be taken by a troll, than the troll has won.

Now about free speech. It is already eroding away in America. If you have enough money, you can block any kind of message you want through the courts. Judges are smoothed talked by lawyers into believing our right to free speech does not exist. Now what makes slashdot great is free speech. lets hope slashdot never blocks anything unless it is, well, subpoenad by the court.. *sigh* (which it has been before i believe)

Re:A little note about free speech (2, Interesting)

lordmatthias215 (919632) | more than 7 years ago | (#18653491)

While I agree that Slashdot shouldn't ban any exercise of free speech, I'm pretty sure one of this site's rules is no advertising your site in discussions, espeically if it has nothing to do with the discussion at hand. This guy is just spamming articles with ads, without making even the slightest effort to make it look like a normal response. I agree that there needs to be a "report abuse" link that /. higher-ups can then review and make a decision based on. There's a difference between free speech and system abuse.

Re:A little note about free speech (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18653843)

I checked the FAQ. They sort of addressed that here: http://slashdot.org/faq/suggestions.shtml [ukdirtypanties.com]

Re:A little note about free speech (0)

Anonymous Coward | more than 7 years ago | (#18653845)

Where do you draw the line between free speech and system abuse?

If there is free speech, it means you tolerate everything including (but not limited to) unpopular opinions, insults about you or your loved ones, ads and whatever.

The moment you start deleting some form of speech because it did not conform to some rule (in this case, the rule being 'no ads'), then you are controlling speech.

You recommend that /. higher ups should be able to remove posts based on some decision. Who's to say that such power won't be abused?

Almost everything in life is in a shade of gray. But in my opinion, free speech is a black & white issue. If you control speech based on ANY rule, then it is no longer free. Just my 0.02 bytes.

In future... (1, Funny)

Anonymous Coward | more than 7 years ago | (#18652409)

After mass production and commoditization, we will have invisibility T-shirts, invisibility sandals, and invisibility shorts.

Fitness (2, Funny)

normuser (1079315) | more than 7 years ago | (#18652621)

As long as there is some sort of fitness standard before you can wear said garments.

Re:In future... (5, Funny)

tsajeff (925056) | more than 7 years ago | (#18652903)

Ahh yes, the Emperor's new clothing line.

Re:In future... (0)

Anonymous Coward | more than 7 years ago | (#18653321)

I, for one, welcome our invisible overlords! sorry, couldn't resist.

Re:In future... (2, Funny)

Anonymous Coward | more than 7 years ago | (#18653695)

They've been here for years, you just noticed?

Error Message (5, Funny)

FooAtWFU (699187) | more than 7 years ago | (#18652421)

Never has this notice been more appropriate:

Nothing for you to see here. Please move along.

*yawn* (1)

vxd (798177) | more than 7 years ago | (#18652527)

Let me know when it's available for visible light so I can go watch Pamela Anderson have sex live.

Re:*yawn* (2, Interesting)

ConvertEJ__ (1084651) | more than 7 years ago | (#18652635)

Yes, just what our society needs. So we get these "invisibility cloaks" and what is next? Use in law enforcement? Cops can spy on us from behind these cloaks? An amendment to the Patriot Act? I'm not saying these are necessarily bad things, but we sure as hell have to weigh the possible negative uses of such a technology.

Following suit with that article about the RIAA pushing for pretexting in California, I could just see them getting their hands on invisibility cloaks.
Be careful pirating music, the RIAA could be in the corner watching!

Re:*yawn* (4, Funny)

BakaHoushi (786009) | more than 7 years ago | (#18653787)

Don't worry. We have the technology to prevent such abuse. Simply place an upside down basket on a stick, and place a dollar bill under it. If a record executive or a lawyer is hidden in a corner, they won't be able to resist and the basket will fall on them.

Re:*yawn* (1)

HateBreeder (656491) | more than 7 years ago | (#18653915)

Actually,

If someone could spy on you from within the cloak, it would no longer be invisible, since he would have to absorb photons coming from the object he's observing, instead of passing them through.

this in turn would make him look like a "dark" spot instead of invisible.

ATTN: Windows/Linux refugees! (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18652673)

Still looking for the "maximize" button when your Mac has "zoom" instead? Take the hint, switcheurs: If you can't deal with multiple windows at once, GTFO of our platform. The Mac wasn't designed for one-track minds.

Re:Error Message (2, Funny)

aldo.gs (985038) | more than 7 years ago | (#18652757)

Nothing for you to see in this wavelength. Please select another one.

Serious Note: Foreign Students & Critical Tec (1, Insightful)

reporter (666905) | more than 7 years ago | (#18652773)

The main article mentions that this cloaking technology has military applications. Given the sensitive nature of this technology, should we prohibit certain foreign students from working on research projects exploring cloaking technology?

In the late eighties, the University of Michigan at Ann Arbor prohibited certain foreign students from participating in government-funded research related to VLSI circuits. At the time, various alarmists in Washington warned that Japan would soon eclipse the USA in high technology, and some politicians wanted to prevent certain foreign nationals at our universities from accessing VLSI technology.

I imagine that cloaking technology would be very interesting to students from Iran (seeking a nuclear bomb), India (aggressively developing advanced nuclear weapons), and China (aggressively building a blue-water navy). Washington has already agreed to give civilian nuclear technology to India even though the Indians (1) have refused to sign the nuclear non-proliferation treaty (NPT) and (2) have aggressively develop nuclear weapons. Should Washington further enhance Indian military ambitions by allowing Indian students to work on cloaking technology at America universities?

Re:Serious Note: Foreign Students & Critical T (1, Funny)

Anonymous Coward | more than 7 years ago | (#18653043)

GOD BLESS AMERICA!
fixed

Re:Serious Note: Foreign Students & Critical T (2, Interesting)

cyphercell (843398) | more than 7 years ago | (#18653313)

If we don't let Japan and China learn about the technology, who will build it? All joking aside, countermeasures already exist and in many cases are far more advanced. Either way India is not considered an enemy http://www.washingtonpost.com/wp-dyn/content/artic le/2006/04/19/AR2006041902480.html [washingtonpost.com] . If you're concerned about outsourcing, don't be, let the Indians go to school in the US, that way at least our universities don't rot from lack of use.

Re:Serious Note: Foreign Students & Critical T (1)

rucs_hack (784150) | more than 7 years ago | (#18654073)

who needs to develop more countermeasures? Mobile phone transmitters could be used, just search for the blank area...

Re:Serious Note: Foreign Students & Critical T (0)

Anonymous Coward | more than 7 years ago | (#18653737)

Who the fuck do you think IS the research department? My school is 53% asian, and 26% caucasian (which includes middle easterners, if you didn't know). And that's *including* the whitey stuff like social sciences and humanities. There are maybe five white guys in a lecture hall of 200 engineers. My most recent physics lab group consisted of two chinese, one japanese, one iranian, and myself (central/east european mutt). One of the chinese guys and the iranian were attempting to get citizenship. This is not uncommon, based on previous groups and discussion sections I've been involved in. The graduate level is even more foreign.

I've had two white professors the entire time I've been there (4 years @ ~16 classes a year). Indians, Turks, Iranians, Iraqis, Georgians, Japanese, Chinese, etc...all with tenure (or with tenure on its way). Ban the foreign nationals and the engineering and science universities would have to shut down, leading to an even wider gap between the U.S. and its tech competitors.

Re:Serious Note: Foreign Students & Critical T (0)

Anonymous Coward | more than 7 years ago | (#18653937)

I agree: Truly it is only safe for America to weild supreme power in this world because they are the only ones who are responsible enough to do so. End sarcasm. Maybe the US should have to sign the nuclear non-proliferation treaty too?

Re:Error Message (1)

morcego (260031) | more than 7 years ago | (#18653179)

Gives a whole new meaning to the phrase "just because I'm paranoid, doesn't mean no one is watching me", hum ?

Invisible to lasers, anyway. (2, Interesting)

AJWM (19027) | more than 7 years ago | (#18652439)

One wavelength hardly invisibility makes, but as the blurb suggests, it renders the target invisible to laser designators. Wonder how much power it can handle, would it be an effective shield against weapons-grade lasers?

Re:Invisible to lasers, anyway. (3, Informative)

Opportunist (166417) | more than 7 years ago | (#18652485)

Weapons-grade lasers (i.e. lasers that do damage themselves) are with todays technology not really an issue. To create damage comparable to conventional methods of kaboom, you'd have to haul around a LOT more material and those pieces also tend to be a LOT more expensive. War is a cost/gain game, so don't expect to see any laser weapons too soon on the battlefields of the world.

What this aims at is laser targeting systems. Those lasers carry hardly enough firepower to cause any damage (ok, should you look RIGHT into them, maybe you might have some problem), but they point out the target to a laser guided weapon. And, well, you can't hit what you can't see (unless you decide to fire a spray of those kickass expensive laser guided weapons, which has not really a good cost/gain relation).

Re:Invisible to lasers, anyway. (4, Interesting)

Kandenshi (832555) | more than 7 years ago | (#18652525)

I'm curious about something though...
I have absolutely no experience/knowledge of these laser targetters, but how much more expensive would it be to be able to use different wavelengths of light?

1. Try wavelength X: Oh darn, they're protecting against that with a shiny cloaking device, so...
2. Try wavelength Y: Profit!!!/explosions

The bomb or whathaveyou is searching for a very specific wavelength(X) right? But still doesn't seem like it should be impossible to program it to cycle through 2-3 wavelengths(X->Y->Z) until it finds your dot to lock onto.

Still, it's a neat toy they're working on. I wouldn't mind one once they build one that's less selective.

Re:Invisible to lasers, anyway. (1)

Opportunist (166417) | more than 7 years ago | (#18652639)

I'm no expert for military grade lasers myself, but as far as I know, you need different media for different wavelengths. I.e. you'd have to mount one laser per wavelenth you want to try.

Re:Invisible to lasers, anyway. (2, Interesting)

ShooterNeo (555040) | more than 7 years ago | (#18654045)

Well, yes, that is true for most convential lasers. Usually, the light emitted is a property of what elements you dope the lasing medium with (for solid state lasers) or what gases you used (for well, gas lasers)

However, if this horribly complex and expensive sound cloaking technology (against just 1 wavelength) ever become a threat, it would be trivial to upgrade the military lasers to a tunable one. There are numerous ways, including using free electron lasers which can be tuned to a wide range of wavelengths at will. Or...other ways. Really, I don't see it being a problem, the researchers saying it could be "useful" are just be sensationalistic. Or perhaps they want military funding, which in my opinion is a waste because it seems incredibly unlikely that nanoscale invisibility armor will ever be practical.

(well, it might be SOMEDAY, but I suspect that era would be around the same era when machines do all the fighting, and we have different considerations.

Russian Dolls (2, Insightful)

Nazlfrag (1035012) | more than 7 years ago | (#18653771)

To combat against multiple frequencies, you could place the cloak for X inside the cloak for Y inside the cloak for Z. Extending this way to full spectrum would be impractical, but multiple frequencies could more easily be blocked.

Re:Russian Dolls (1)

Venerable Vegetable (1003177) | more than 7 years ago | (#18654067)

That would only work if the cloak was completely transparant to all frequencies except the one it's bending. I seriously doubt that. More likely, the outside cloak will bend one frequency around it and reflect the others like normal materials.

Re:Invisible to lasers, anyway. (1)

hazee (728152) | more than 7 years ago | (#18654087)

One strategy might be to only turn on the device after the bomb or whatever is on its way.

If you just switched it on at the last moment and then moved your tank, that might work.

You'd be given advance notice that something was inbound by the fact that you were being illuminated in the first place.

Re:Invisible to lasers, anyway. (1)

Columcille (88542) | more than 7 years ago | (#18653115)

"Weapons-grade lasers (i.e. lasers that do damage themselves) are with todays technology not really an issue. To create damage comparable to conventional methods of kaboom, you'd have to haul around a LOT more material and those pieces also tend to be a LOT more expensive. War is a cost/gain game, so don't expect to see any laser weapons too soon on the battlefields of the world."

I didn't RTFA (hey, this is slashdot) but from the summary it sounds like a truly effective cloak of this sort is still some time away. A truly effective laser weapon is also still some time away. But it sounds like each of those will eventually make an appearance. Might not be a bad idea to consider laser weapons an issue so that when they do make an appearance we just might have something that can protect from them. I assume this is what military R&D is all about, come up with ways to defeat not-yet-existing systems so that when they exist we won't have to play catch-up.

Re:Invisible to lasers, anyway. (1)

iamacat (583406) | more than 7 years ago | (#18653659)

You are forgetting the fact that, unlike kaboom, laser travels instantly (unless you try to shoot Martians) and precisely. This makes them better suited for shooting down airplanes and cruise missiles. There is also an option of using a smaller laser to blind the pilot.

Re:Invisible to lasers, anyway. (0)

Anonymous Coward | more than 7 years ago | (#18653873)

But this technology would be awesome blocking laser light shows at Yanni concerts. Wait.. no.. Michael Bolton.

Although laser designator and awesome firepower would also be an acceptable way of dealing with these unentertainers.

Re:Invisible to lasers, anyway. (3, Funny)

The Orange Mage (1057436) | more than 7 years ago | (#18652499)

Well, I guess this means we now have an effective anti-shark defense system...

Re:Invisible to lasers, anyway. (3, Funny)

Hal_Porter (817932) | more than 7 years ago | (#18653205)

The S1A1 remote controlled great white shark [newscientisttech.com] has a secondary offensive capability based on 1) rows of sharp teeth and 2) neural implant boosted hunger, all guided by a keen sense of smell. Obviously, we planned for Chinese frogmen in invisibility suits.

This is all classified info BTW, please kill yourself after reading it, unless you happen to have SPECOPS/JAWS clearance.

Re:Invisible to lasers, anyway. (4, Insightful)

cyphercell (843398) | more than 7 years ago | (#18652713)

I remember watching Black Hawk Down, and noticing that this troop (a motley crew of special forces) had the benefit of night vision effectively throughout the movie. When watching it I thoroughly believed that this was an advantage that made them successful in surviving the event. Imagine to armies fighting with night vision while one side has their special forces being cloaked.

Re:Invisible to lasers, anyway. (4, Informative)

YGingras (605709) | more than 7 years ago | (#18653145)

Except that night vision devices aren't restricted to a single wavelength. Night goggles only amplify the light in the whole spectrum. The whole thing, not a single wavelength. The output is converted to monochrome to stimulate the more sensitive rod cells. By limiting color output the pupil stays more dilated and can gather more light. Its the same thing with astronomical telescopes. You read your maps with a red light and you get eyes pieces with exit pupil [wikipedia.org] matching your night time pupil diameter.

Re:Invisible to lasers, anyway. (2, Interesting)

ozydingo (922211) | more than 7 years ago | (#18653247)

Even if night vision did work on detecting a single frequency, it wouldn't be a robust viable solution. Simply change the wavelength your night vision operates on, and the cloaking devices become useless. For this reason this technology as it stands currently is really not a viable solution for any military application as long as your opponents know anything about it (better hope they don't read Slashdot!)

Don't get me wrong, I think it's still cool and a good first step, just not with any militarily robust applications.

Re:Invisible to lasers, anyway. (2, Insightful)

rtb61 (674572) | more than 7 years ago | (#18653667)

The cloaking device is most likely just a spectrum shifting coating. Catch is, a dirty tank, would be a dead tank.

Re:Invisible to lasers, anyway. (1)

cyphercell (843398) | more than 7 years ago | (#18653353)

So if the cloaking worked out to say 95% then night vision goggles could probably be used as a countermeasure? If so, how well do you think it might work (I'm guessing 100%)?

Re:Invisible to lasers, anyway. (0)

Anonymous Coward | more than 7 years ago | (#18654111)

Night vision devices are indeed restricted to a single wavelength. They cannot output color.
The intermediate amplification stages involve production of an electron for every photon striking the cathode plate. Later the multiplied electrons strike a phosphor screen to produce the image you see. The phosphor throws off visible photons in one narrow wavelength. The phosphor chosen invariably has an output peak of around 520nm- medium green- chosen due to its place on the human eye's sensitivity peak.
It is perfectly feasible to create a night vision device with red, blue, orange, etc output. Color output is not possible. As an aside, an infrared-lit scene has no color to be captured.
Regarding your latter sentences, limiting color output in such a way as you mention has no affect on pupil dilation.
It is arguable that the longer wavelength (and thus lower energy) of red light might degrade the function of rhodopsin more slowly, but this effect is certainly not present with green light.

Re:Invisible to lasers, anyway. (1)

zCyl (14362) | more than 7 years ago | (#18654139)

Night vision devices are indeed restricted to a single wavelength. They cannot output color.

It's not a question of output, it's a question of input, since presumably the invisible-cloak-wearer is outside of the night vision goggles. And they input many wavelengths.

Roddenberry effect (1, Funny)

Anonymous Coward | more than 7 years ago | (#18653005)

If it renders lasers less effective as weapons, then the natural result is development of multi-spectrum Phasers. You heard it hear folks! The cloaking device came first!

Frickin Romulans.

Re:Invisible to lasers, anyway. (4, Interesting)

mgv (198488) | more than 7 years ago | (#18653039)

One wavelength hardly invisibility makes, but as the blurb suggests, it renders the target invisible to laser designators.

Invisible to laser speed checks would have some non military applications.

Michael

Happy Harry (1, Funny)

jcarkeys (925469) | more than 7 years ago | (#18652505)

Harry Potter sits in the corner of the lab in his cloak snickering while the research scientists are excited to get one wavelength invisible.

Re:Happy Harry (1, Insightful)

Anonymous Coward | more than 7 years ago | (#18652723)

You do know Harry Potter is a fictional character, right?

Re:Happy Harry (1)

daveb (4522) | more than 7 years ago | (#18652851)

You do know Harry Potter is a fictional character, right?


Yes muggle. No need to fret, "Harry is fictional".


There's no such thing as wizards we^h^h They don't exist.

Re:Happy Harry (1)

Eli Gottlieb (917758) | more than 7 years ago | (#18653131)

Wizards don't know enough about technology to use Slashdot! You must be a Squib.

Re:Happy Harry (4, Funny)

slashbob22 (918040) | more than 7 years ago | (#18652863)

You do know Harry Potter is a fictional character, right?
Which is why he is invisible in the non-fictional wavelength.

How much does it cost? (1)

Opportunist (166417) | more than 7 years ago | (#18652511)

That's what's gonna dictate whether it will be seen on the battlefield or not. If it's cheaper to produce another gunship or tank than to stealth an existing one, it will probably only be used on first strike weapons.

Re:How much does it cost? (1)

ozydingo (922211) | more than 7 years ago | (#18653265)

In its current incarnation it won't be seen on the battlefield at all. Invisible to targeting lasers? Use a different laser wavelength. Invisible to night vision? (Does night vision really only work on a single frequency anyway?) Change the frequency you're looking at. It's not a reliable solution for anything battlefield-worthy until it can encompass a range of frequencies--but it's a good academic first step!

Re:How much does it cost? (0)

Anonymous Coward | more than 7 years ago | (#18653727)

Err... invisibility cloak? It won't be seen on the battefield either way. Duh.

One step towards the most duped story (4, Interesting)

noidentity (188756) | more than 7 years ago | (#18652531)

Sure, each article is a slightly different take, but I swear there have been at least four previous articles about some kind of invisibility device in the past year, all turning out to really be invisibility in a very restricted sense, i.e. a particular electronic device doesn't "see" the object.

Re:One step towards the most duped story (1)

MarkRose (820682) | more than 7 years ago | (#18652667)

Are you telling me you have the foresight to see more of these coming? Isn't that blindingly obvious? I wish I had that kind of vision. I have yet to see an invisibility device myself, FWIW.

Re:One step towards the most duped story (1)

edwardpickman (965122) | more than 7 years ago | (#18652989)

Don't worry I take there's an upcoming post on a research group's article that claims invisibility when the viewer closes their eyes. While also not true invisibility the technique does work with all light spectrums. The researchers aren't suggesting a method to get the enemy to close their eyes but they do point out that everything has a downside.

Re:One step towards the most duped story (1)

Grave (8234) | more than 7 years ago | (#18653231)

Oh, it's easy to get the enemy to close their eyes. Just get set their Slashdot comment filter to only show trolls.

Re:One step towards the most duped story (1)

zCyl (14362) | more than 7 years ago | (#18654121)

Don't worry I take there's an upcoming post on a research group's article that claims invisibility when the viewer closes their eyes.

This has been done. [wikipedia.org]

Meh (4, Funny)

vertigoCiel (1070374) | more than 7 years ago | (#18652571)

Wake me up when you've got an "invisibility" device that'll let me sneak into the girls locker room without getting seen.

Re:Meh (1)

NeilTheStupidHead (963719) | more than 7 years ago | (#18652601)

Your so-called 'invisibility device' is commonly known as a $50 at a strip club.

Re:Meh (3, Funny)

digitig (1056110) | more than 7 years ago | (#18652731)

Your so-called 'invisibility device' is commonly known as a $50 at a strip club.
I tried that. It didn't work. My wife still saw me :-(

Re:Meh (3, Funny)

NeilTheStupidHead (963719) | more than 7 years ago | (#18652751)

If your wife works at a strip club in the first place, I don't see why she had an issue with it. :P

Re:Meh (5, Funny)

Anonymous Coward | more than 7 years ago | (#18652923)

I think I have one, I've been invisible to girls for years.

You won't see anything but yourself (1)

Richard Kirk (535523) | more than 7 years ago | (#18653939)

Light can usually go along a path in either direction. If light isn't getting from you to the outside world. If the 'invisibility cloak' is a type of Luneborg lens with phonotonics materials to get the high refractive incides needed to get light to avoid the bit in the middle - the sort of thing in this month's 'Scientific American' - then yo will seem to be at the centre of a shiny ball. Kinda interesting to know how you would decide when all the bad guys had gone away, and it was save to take a peek out.

Stick to the half-silvered mirror, ya perv.

Laser sharks (4, Funny)

unchiujar (1030510) | more than 7 years ago | (#18652727)

Oh noes, invisible sharks with lasers !!!

Re:Laser sharks (1, Funny)

Anonymous Coward | more than 7 years ago | (#18653011)

-I am sorry sir, we couldnt get sharks.
-What do we have?
-Sea Bass
-Right, Are they invisible?
-Only to one wavelenght
-Oh well, that's a start.

Sadder, but wiser. (2, Funny)

Anonymous Coward | more than 7 years ago | (#18652781)

A friendly note to the photonics project managers, researchers and general staff:

Don't make the same mistake I did. Learn from my experience that one should never, ever put the invisibility generator on top of the anti-gravity device.

Please.. (-1, Flamebait)

lightversusdark (922292) | more than 7 years ago | (#18652789)

Don't ever post any variation of this bullshit again.

It was bad enough resorting to Digg et al on April 1st just not to be wholly uninformed.
(Note: Planning a worm/virus launch? Your sysadmin's newsfeeds will be full of shit on April 1st).
Thing is, it's over a week since I killed time on Digg because of ./the1st. That's when I saw it on Digg, and even then I thought "This was on slashdot months ago, and it was old news back then."

Oh no! (2, Funny)

Mikachu (972457) | more than 7 years ago | (#18652819)

It's Denton. Remember the briefing.

Don't mod me down just because you don't get it. ;)

Re:Oh no! (1)

freyyr890 (1019088) | more than 7 years ago | (#18653081)

Deus Ex, right?

That was looking to be a good game, until I lost the disc in the third mission...

Re:Oh no! (1)

Mikachu (972457) | more than 7 years ago | (#18653091)

Right.

Third mission? Aww, that sucks. Amazing game.

Re:Oh no! (1)

freyyr890 (1019088) | more than 7 years ago | (#18653117)

Suppose I could still no-cd it, since it's still on my hard drive and it is a full install...

*Rushes to cracks site.*

night-vision goggles or laser target designators.. (0)

Bananatree3 (872975) | more than 7 years ago | (#18652833)

Orrrr...Hiding in Dark Rooms!!

Invisibility cloak? (0)

Anonymous Coward | more than 7 years ago | (#18652921)

Hey, cool! A cloak of invisibility +5 funny!

So, where is it? (1, Funny)

FMota91 (1050752) | more than 7 years ago | (#18652925)

Nothing to see here, move along.

Playing (0)

Anonymous Coward | more than 7 years ago | (#18652935)

Playing Harry Potter just became more fun than ever!

Re:Playing (0)

Anonymous Coward | more than 7 years ago | (#18652979)

"Draco, Draco, wherefore art thou Draco?"

is it telling the future that.... (1)

holywarrior21c (933929) | more than 7 years ago | (#18652955)

the coming of purdue nukem?

Obligatory Star Trek Quote (1)

lord_mike (567148) | more than 7 years ago | (#18652985)

Spock: Invisibility is theoretically possible, Captain--selectively bending light. But the power cost is enormous. They may have solved that.

Problem with Invisibility Cloaks in General ... (2, Interesting)

i_wanna_be_a_scienti (1042298) | more than 7 years ago | (#18653095)

What about the ground? Can the light even bend around an object that is stuck to another? I don't think so ...
So wouldn't it make two dark spots on the ground? that could be used to identify if someone is using an invisibility cloak.

Precious, my precious (5, Funny)

OldManAndTheC++ (723450) | more than 7 years ago | (#18653107)

According to TFA:

Leonhardt, a professor of theoretical physics, wrote a commentary piece about the Purdue paper appearing in the same issue of Nature Photonics. In the commentary, he compares the Purdue design to the Roman creation of "the first optical metamaterial," a type of glass containing nanometer-scale particles of gold. In ordinary daylight, a cup made of the glass appeared green, but then it glowed ruby when illuminated from the inside.

So basically, this will be made out of (a form of) gold, and encircle the object to be rendered invisible?

I'm betting that, in order to work, it will need to be inscribed with the phrase: Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul.

Re:Precious, my precious (4, Funny)

swillden (191260) | more than 7 years ago | (#18653211)

Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul.

Please tell me you looked that up.

night vision goggles and lasers, no. (2, Insightful)

plasmacutter (901737) | more than 7 years ago | (#18653155)

first off, theyre slowly replacing aging nvg's with FLIR systems, second nvg's sensed a spectrum, though i forgot which one, ultraviolet was it?, the point is its not a single wavelength... even if i'm wrong and it is only one wavelength then it would be trivial to broaden the spectrum or have the sensors modulate.

the same thing with a laser, you modulate the beam according to a hash function for each laser/missile pair, the string that produces the hash code could easily be communicated real time from air support to the troops on the ground painting the target.

congrats, you added 3 more seconds at most to a target's life. even if that allows say, a tank, to get off one more shot the expense and other undocumented and probably cumbersome changes are not worth it.

now if/when they develop one that cloaks across the entire practical spectrum of light you may have a problem, but not one that cant be solved through the trivial process of painting the ground in front of the target and having the guidance system deliberately raise the elevation of the impact point by.. say.. 10 feet... let alone using IR or radar/gps guidance instead.

Re:night vision goggles and lasers, no. (1)

hazee (728152) | more than 7 years ago | (#18654131)

Not quite sure what you mean about modulating a laser beam. Presumably you can switch it on and off in whatever fancy scheme you like, but it's going to remain the same wavelength. As others have mentioned, wouldn't you need different lasers to get different wavelengths? I seem to recall that dye lasers shift the output from one frequency to another, but not sure how practical this would be in a battlefield.

Also, as regards communications between planes and ground troops - presumably planes want to minimise their transmissions, to prevent becoming targets themselves, especially if they're trying to be stealthy. How long does a bomb take to fall from 20,000 feet? I wouldn't want to broadcast my location for that long. Ditto for the ground troops.

Finally, mightn't 3 seconds be long enough to save the target's life? If they just switched it on at the last second, and then dodged?

wonder if Masamune Shirow knows about this? (2)

Petkov (1011081) | more than 7 years ago | (#18653269)

Ghost in the shell anyone?

Completed already? (1)

Non-CleverNickName (1027234) | more than 7 years ago | (#18653281)

Hey, for all we know, someone could have already completed the perfect cloaking device...they just can't find the off switch.

Lightbending 101 (2, Informative)

stemcel (1074448) | more than 7 years ago | (#18653385)

This innovation and others like it have seen far too much press already. I know, I know, it's slashdot and no one RTFA anyway, but if you did you'd quickly realize that there really is nothing to see here. Let me explain at least for those of you who will read a comment if not any of the articles appearing in popular science sources for the last several months:

Imagine for the moment placing an object behind a mirror. Better yet, inside a mirror. Amazing! You cloaked it from observation from visible wavelengths! Understood, this is much more meta and complex than all that. It bends the light around instead of sending it away. But that's all. In the same way that you can't see anything on the other side of the mirror, nothing on the other side of the mirror can see you. We're not going to see invisibility cloaks or special forces in lightbending armor out of this, because even if the technology were practical and cheap the special forces would still be blind. Any light you let in is light that's not making you invisible by being elsewhere.
These results are undeniably groundbreaking, but they are received as something entirely different from what they really are.

obligatory ghost in the shell. (1)

plasmacutter (901737) | more than 7 years ago | (#18653493)

what say you to the thermoptic camo from ghost in the shell, which is an actual clothing item composed of millions of pico to nano scale fiber optic cameras and projectors which fluidly blend you into the surroundings. a semitransparent veil covers the face, completing the full body cloak, but facilitating vision in the same way those pointilism ads across city buses present a picture to onlookers while allowing passengers a view outside.

how much more complex would it be to create light bending hardware with these kind of microperforations.

Re:Lightbending 101 (1)

freedumb2000 (966222) | more than 7 years ago | (#18653863)

Ok, how do mirrored sunglases work then?

Re:Lightbending 101 (1)

Venerable Vegetable (1003177) | more than 7 years ago | (#18654047)

Uuh, what about covering everything except the eyes?

Or use it on robots which don't need to see?

Link to Paper (1)

nleaf (953206) | more than 7 years ago | (#18653743)

The paper can be downloaded for free on arxiv.org: Optical Cloaking with Non-Magnetic Metamaterials [arxiv.org]

I see a lot of comments along the lines of "One wavelength cloaking will never be useful because of ____ and ____." Firstly, the vast majority of research is done incrementally, and this is a good first step. Secondly, funding is a necessary evil, and towards that end nothing beats a working demonstration that smells like fresh progress.

What is it like to wear ? (1)

Alain Williams (2972) | more than 7 years ago | (#18653961)

I assume that if you wear one of these then you see nothing from 'outside' at that particular shade of red.

So if they succeed in making one that works at all wavelengths of visible light - one could not see out. However: imperfections would let some light leak in, but the direction that it came from might be distorted and so give a very blurred view of the rest of the world.

Re:What is it like to wear ? (1)

Godman (767682) | more than 7 years ago | (#18654079)

Which is why you don't cover your fricking eyes.

And if you need to be absolutely hidden, you *gasp* put your hands over them, or wear a baseball type cap that will enable you to see well enough to walk, but not be seen.
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