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Scientists Freeze Pulse Of Light

simoniker posted more than 10 years ago | from the mr-bigglesworth-looks-on dept.

Science 343

Smitty825 writes "After slowing down light to slow speeds, scientists at Harvard University have been able to stop light for a very brief period of time without destroying its energy. The article explains how it is different from this previous light-stopping science story - this will hopefully help the development of quantum computers and ways to communicate over long distances without being eavesdropped on."

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FP (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7688166)

FP!

Re:FP (-1, Troll)

Anonymous Coward | more than 10 years ago | (#7688463)

Try to be a bit heterosexual next time, hm?

So isolinear chips are on the way now? (-1, Offtopic)

Blaede (266638) | more than 10 years ago | (#7688170)

Maybe the Intel Optium series is being taped out right now? Sadly, Doom 3 will still run at 3fps on them.

Offtopic? How so? (-1)

Anonymous Coward | more than 10 years ago | (#7688217)

Isolinear chips are quite a serious subjuct.

Re:Offtopic? How so? (-1, Offtopic)

sujan (464326) | more than 10 years ago | (#7688416)

Obviously, the mods are a retarded bunch.

Knights of Ni: Ni! Ni! Ni! Ni! Ni! Ni!
Arthur: Who are you?
Knight of Ni: We are the Knights who say..... "Ni"!
Arthur: (horrified) No! Not the Knights who say "Ni"!
Knight of Ni: The same.
Other Knight of Ni: Who are we?
Knight of Ni: We are the keepers of the sacred words: Ni, Ping, and Nee-womm!
Other Knight of Ni: Nee-womm!
Arthur: (to Bedevere) Those who hear them seldom live to tell the tale!
Knight of Ni: The knights who say "Ni" demand..... a sacrifice!
Arthur: Knights of Ni, we are but simple travelers who seek the enchanter who
lives beyond these woods.
Knights of Ni: Ni! Ni! Ni! Ni! Ni! Ni! Ni! Ni! Ni!
Bedevere: No! Noooo! Aaaugh! No!
Knight of Ni: We shall say "Ni" to you... if you do not appease us.
Arthur: Well what is it you want?
Knight of Ni: We want.....

(pregnant pause)

A SHRUBBERY!!!!

(minor music)

Arthur: A WHAT?
Knights of Ni: Ni! Ni!! Ni! Ni!
Arthur; No! No! Please, please, no more! We will find you a shrubbery.
Knight of Ni: You must return here with a shrubbery... or else you will never
pass through this wood... alive.
Arthur: O Knights of Ni, you are just and fair, and we will return with a
shrubbery.
Knight of Ni: One that looks nice.
Arthur: Of course!
Knight of Ni: And not too expensive.
Arthur; Yes!
Knight of Ni: Noowwwww.... GO!

(music)

Arthur: O Knights of Ni. We have brought you your shrubbery. May we go now?
Knight of Ni: Yes, it is a good shrubbery. I like the laurels particularly.
But there is one small problem....
Arthur: What is that?
Knight of Ni: We are now no longer the Knights Who Say "Ni"!
Other Knights of Ni: Ni! Shh! Shh!
Knight of Ni: We are now the Knights who say "Ekky-ekky-ekky-ekky-z'Bang, zoom-Boing, z'nourrrwringmm".
Other Knight of Ni: Ni!
Knight of Ni: Therefore, we must give you a test.
Arthur: What is this test, O Knights of.....
Knights who 'til recently said "Ni"?
Knight of Ni: Firstly, you must find....

ANOTHER SHRUBBERY!!!

(minor music)

Arthur: Oh not another shrubbery!!
Knight of Ni: (excitedly) THEN... Then, when you have found the shrubbery,
you must place it here, beside this shrubbery, only slightly
higher, so we get the two-level effect with a little path
running down the middle.
Other Knights of Ni: A path! A path! A path! Shh, shhh. Ni! Ni!
Knight of Ni: Then, when you have found the shrubbery, you must cut down the
mightiest tree in the forest...
Wiiiiiithh.... A HERRING!

Who wants to stop light? (5, Funny)

trentblase (717954) | more than 10 years ago | (#7688175)

Now if they could only figure out how to stop SPAM

Re:Who wants to stop light? (1, Funny)

glenebob (414078) | more than 10 years ago | (#7688196)

Is there a such thing as light spam? Because if there is, you know, maybe it would easier to start with that...

Re:Who wants to stop light? (3, Funny)

umofomia (639418) | more than 10 years ago | (#7688215)

Is there a such thing as light spam? Because if there is, you know, maybe it would easier to start with that...
Yep. [spam.com]

Re:Who wants to stop light? (1, Funny)

glenebob (414078) | more than 10 years ago | (#7688283)

A ray of hope coming to us in a brightly colored can!!!

Re:Who wants to stop light? (0, Offtopic)

noselasd (594905) | more than 10 years ago | (#7688312)

Well, humans do a lot of light pollution, you can easily call that spamming..

Re:Who wants to stop light? (0)

Anonymous Coward | more than 10 years ago | (#7688359)

If you would like to stop spam
then take a look on this list
of spam tools [all-technology.com] .

Re:Who wants to stop light? (2, Funny)

Jugalator (259273) | more than 10 years ago | (#7688407)

It should now just be a matter of stopping the light travelling through the optic fiber connections. Sure, it stops all other data travelling through the fiber as well, but who said stopping spam never came without certain sacrifices? :-)

I can't wait for the future development... (5, Funny)

Ratface (21117) | more than 10 years ago | (#7688178)

Imagine going out to a club and getting a frozen "light cube" in your drink which releases a stream of photons as it melts.

Could bring a whole new dimesnion to the humble Tequila Sunrise huh?

Re:I can't wait for the future development... (2, Funny)

Anonymous Coward | more than 10 years ago | (#7688197)


thrust me, you dont want a block of sodium in your drink :)

Re:I can't wait for the future development... (4, Funny)

trentblase (717954) | more than 10 years ago | (#7688237)

"thrust me"

Is that going to be your pickup line at said bar?

Re:I can't wait for the future development... (1)

metlin (258108) | more than 10 years ago | (#7688317)

From the article -


"I think it's moving us in the right direction," he said.


What, the light? Or...

Aww forget it!!!

Re:I can't wait for the future development... (0)

Anonymous Coward | more than 10 years ago | (#7688358)

no it will be: "Thrust me, I know what Im doing" :)

Re:I can't wait for the future development... (0, Funny)

glenebob (414078) | more than 10 years ago | (#7688207)

Or you could drop one in your beer and then it would be li... um I'm stopping right here, sorry...

Re:I can't wait for the future development... (1)

Basje (26968) | more than 10 years ago | (#7688322)

A tequila sunrise does not have ice in it...

Re:I can't wait for the future development... (1)

Tenebrious1 (530949) | more than 10 years ago | (#7688331)

"light cube" in your drink which releases a stream of photons as it melts.

Ah, but if those photons come out in phase and all at the same time, you have a laser pulse! Frozen lazer pulses stored in ice "bullets", hey, we may yet see laser pistols in our lifetime!

Re:I can't wait for the future development... (1)

Grizzlysmit (580824) | more than 10 years ago | (#7688482)

Ever wanted to adopt an alien?

Thank you for offering to adopt me :-D.

Re:I can't wait for the future development... (0)

Anonymous Coward | more than 10 years ago | (#7688484)

Like this [firebox.com] you mean?

Man...Imagine the vaccuum (4, Interesting)

mingust (726690) | more than 10 years ago | (#7688179)

Oh...wait. Voids allow light to travel faster. shame on me. What color is stopped light if it retains its energy?

Duh! (1)

raehl (609729) | more than 10 years ago | (#7688327)

It doesn't have any color - it's STOPPED.

If it's STOPPED, it ain't ever going to get to your eye, see? Erm, I mean, not see?

Maybe you you ran your eye into it or something....

Re:Duh! (1)

DigiShaman (671371) | more than 10 years ago | (#7688342)

If you can messure it's frequency in a before and after state, then you can determine whether or not it's been red/blue shifted.

Ah, but... (1)

raehl (609729) | more than 10 years ago | (#7688381)

If it went in one color, and came out another color, what color was it when it wasn't moving?

Re:Ah, but... (0, Funny)

Anonymous Coward | more than 10 years ago | (#7688466)

red, of course. (And green before and after)

Re:Man...Imagine the vaccuum (0)

vaccum pony (721932) | more than 10 years ago | (#7688328)

It doesn't matter, you can't see it. If it's stopped, it is not going to your eye.

Re:Man...Imagine the vaccuum (3, Funny)

trentblase (717954) | more than 10 years ago | (#7688352)

It's the color of one hand clapping. Seriously, this is the same type of question as "if a tree falls in the woods..."

Color == frequency (5, Insightful)

flakac (307921) | more than 10 years ago | (#7688385)

Light doesn't actually have "color". Color is our perception of the wavelength of the light. There's another article on BBC [bbc.co.uk] that explains the experiment in greater detail. Essentially, they didn't actually freeze the photons, ie. made them stop moving, but used a different method to make the photons bounce back and forth in place. So the "color" should have remained the same.

Okay... (3, Insightful)

autopr0n (534291) | more than 10 years ago | (#7688180)

One of the most annoying things about slashdot is their tendency to post completely vacuous science stories. Would it have been that hard to look up the actual paper before posting, or at least any information at all? All this story tells us is that it doesn't involve storing the photons in an atom as other researchers did. Oh, and that it's "very clever". How nice.

Does the laziness of slashdot "editors" truly know no bounds? If you're not interested in doing the work, why not find people who are?

oh you little fentster (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7688232)

I just got done pounding the shit out of KF. Thought I would check in before going to sleep.

Re:oh you little fentster (0)

Anonymous Coward | more than 10 years ago | (#7688477)

Are you aware of the insult you were just posting? For those of you who don't know: fentster in German means Windows!

Shame on you too!

Well you could have found it (5, Informative)

loadquo (659316) | more than 10 years ago | (#7688250)

Like I did here. [lanl.gov]

Re:Okay... (-1, Redundant)

Anonymous Coward | more than 10 years ago | (#7688258)

That's why comments exist. It's YOUR job!

Stopped light... (5, Funny)

surstrmming (674864) | more than 10 years ago | (#7688184)

Makes me think of a physics joke.

Q: What is the difference between stopped light and darkness?

A: You know where darkness is.

Re:Stopped light... (-1)

glenebob (414078) | more than 10 years ago | (#7688223)

There should be a moderation for horribly, painfully not funny. Even the most hard core physicist should be able to do better than that!

Re:Stopped light... (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7688251)

agreed, i mean wtf

Re:Stopped light... (0)

Anonymous Coward | more than 10 years ago | (#7688336)

Dude you must be kidding.. I'm going to tell that joke to EVERYONE tomorrow at work, it's hilarious. I'm going to take credit for it though... I'll tell em "I was in the 10th floor bathroom spanking my monkey, just sitting there sliding my wanker between the bottom of the toilet seat and the cold porcelain when out shot this hilarious joke!"

Speaking of light and darkness... (5, Funny)

Anonymous Coward | more than 10 years ago | (#7688291)

Here's a quote from Terry Pratchett you might like:

"Light thinks it travels faster than anything but it is wrong. No matter how fast light travels it finds the darkness has always got there first, and is waiting for it."

Reminds me of another physics joke... (5, Funny)

raehl (609729) | more than 10 years ago | (#7688335)

Officer: "Do you know how fast you were going?"

Heisenberg: "No, but I know exactly where I am!"

Re:Reminds me of another physics joke... (0)

Anonymous Coward | more than 10 years ago | (#7688422)

Yeah hahaha good one! That reminds me of the same exact joke posted just the other day [slashdot.org] !

In Soviet Russia... (-1, Funny)

Anonymous Coward | more than 10 years ago | (#7688185)

Had to say this: in soviet russia, the Light stops you !

Very interesting... (4, Interesting)

twoslice (457793) | more than 10 years ago | (#7688189)

development of quantum computers and ways to communicate over long distances without being eavesdropped on.

I thought that light is a visual thing. How does one "eavesdrop" on light?

You can't, because... (0)

Anonymous Coward | more than 10 years ago | (#7688204)

...if you eavesdrop on it, you capture it and the signal is lost to it's target. And once the recipient notices this, the transmission will end. Grabbing the data is to signal you're eavesdropping.

Re:Very interesting... (1)

TitanBL (637189) | more than 10 years ago | (#7688295)

Imagine two naval vessels using Morris code and signal lamps to communicate - a 3rd party could "eavesdrop" on the conversation without disrupting the transmission of the message.

Re:Very interesting... (1)

trentblase (717954) | more than 10 years ago | (#7688339)

I think the grandparent was implying that the literal definition of evesdropping means to listen to a conversation "out of sight". If you are out of sight, you can't see the transmission. Admittedly, the word "listen" can be generalized to mean "receive data".

Phillip Morris? (2, Funny)

raehl (609729) | more than 10 years ago | (#7688345)

Messeges in Phillip Morris code are automatically subpoenaed by Congress anyway.

God damn, subpoenaed is an ugly word.

Now imagine... (1)

raehl (609729) | more than 10 years ago | (#7688351)

Two ships using Morse code to communicate with a laser, and a 3rd party positioning their ship in between the two to eavesdrop on the laser, and then you'll have a better analogy. The receiving ship knows that someone is listening to the message because they're not getting it.

Signal lamps are multi-directional, photons only go one way.

Re:Very interesting... (1)

VanillaCoke420 (662576) | more than 10 years ago | (#7688453)

Depending on what freuqency we're talking about, I suppose you could eavesdrop on electromagnetic radiation in a few different ways?

Apparently, there is energy loss (5, Informative)

ultraw (99206) | more than 10 years ago | (#7688192)

The article mentions clearly:

"We have succeeded in holding a light pulse still without taking all the energy away from it," said Mikhail D. Lukin, a Harvard physicist.

This is somehow different from "...without destroying its energy." like it is stated in the posting. Maybe a subtle detail, but not quite the same.

However, a briliant achievement. Kuddos.

Re:Apparently, there is energy loss (4, Insightful)

LordLucless (582312) | more than 10 years ago | (#7688446)

Well, "destroying its energy" would be a rather major accomplishment, if I remember my highschool lessons regarding conservation of energy...

Really light pocket light (1, Offtopic)

Mr Europe (657225) | more than 10 years ago | (#7688195)

Soon we can pack the pocket light full of light in stead of heavy batteries !

At least it sound _light_ not heavy.

What does this mean for space travel? Anything? (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7688198)

Grrrr....when will we figure out a practical way to travel to other planets?!??

I have my towel packed and ready to go!

Company slogan (2)

mingust (726690) | more than 10 years ago | (#7688202)

"I think it's moving us in the right direction," he said. "Moving forward at the speed of light"? uh oh

quick way to the future (-1)

Anonymous Coward | more than 10 years ago | (#7688210)

can we travel through time if we have sunglasses made out of that stuff ?

consumer applications? (-1)

dark_day (581199) | more than 10 years ago | (#7688212)

maybe this technology could be applied to beat the flash from speed cameras ;-)

Interesting note/errata (4, Interesting)

segment (695309) | more than 10 years ago | (#7688213)

Harnessing light particles to store and process data could aid the still distant goal of so-called quantum computers, as well as methods for communicating information over long distances without risk of eavesdropping.

But today the NSA's snooping capabilities are in jeopardy, undermined by advances in telecommunications technology. Much of the information the agency once gleaned from the air waves now travels in the form of light beams through fiber-optic cables crisscrossing continents and ocean floors. That shift has forced the NSA to seek new ways to gather intelligence -- including tapping undersea cables, a technologically daunting, physically dangerous and potentially illegal task.

In the mid-1990s, the NSA installed one such tap, say former intelligence officials familiar with the covert project. Using a special spy submarine, they say, agency personnel descended hundreds of feet into one of the oceans and sliced into a fiber-optic cable. The mixed results of the experiment -- particularly the agency's inability to make sense of the vast flood of data unleashed by the tap -- show that America's pre-eminent spy service has huge challenges to overcome if it hopes to keep from going deaf in the digital age.

Details of the NSA cable-tapping project are sketchy. Individuals who confirm the tap won't specify where or when it occurred. It isn't known whether the cable's operator detected the intrusion, though former NSA officials say they believe it went unnoticed. Nor is it known whether the NSA has attempted other taps since. Efforts to intercept all sorts of signals -- ranging from military radar to international phone calls -- are among the most highly classified U.S. government operations. Leaking information about interception methods is a federal crime punishable by imprisonment.
[Source [politrix.org] ]

If the NSA supposedly managed to tap into fiber (light) what makes this guy so sure his studies would minimize/cut/halt the risk of eavesdropping? "Splice the line, and you cut off the light, at least momentarily," says Wayne Siddall, an optical engineer at Corning Fiber in Corning, N.Y. Even a second's interruption could be noticed by a cable's operator. Cable companies typically build systems with duplicate lines that take diverging routes, in case one of them is damaged or severed. One retired NSA optical specialist insists that the NSA devised a way to splice a fiber without being detected. "Getting into fiber is delicate work, but by no means impossible," the former specialist says. Neither he nor the NSA will discuss the matter further.

Spy agency taps into undersea cable [com.com]

NSA Tapping Underwater Fiber Optics [slashdot.org]

And the list goes on and on. Bear in mind the NSA's date of achieving this, in comparison to the tech growth scale, I'd be willing to say that whatever Harvard is doing in being closely watched, if not already known.

Re:Interesting note/errata (4, Interesting)

segment (695309) | more than 10 years ago | (#7688249)

Good old fashioned history [slashdot.org] ... Now only I could get my damn old UID [slashdot.org] back... Taco?

Submarine cable interception

Submarine cables now play a dominant role in international telecommunications, since - in contrast to the limited bandwidth available for space systems - optical media offer seemingly unlimited capacity. Save where cables terminate in countries where telecommunications operators provide Comint access (such as the UK and the US), submarine cables appear intrinsically secure because of the nature of the ocean environment. 49. In October 1971, this security was shown not to exist. A US submarine, Halibut, visited the Sea of Okhotsk off the eastern USSR and recorded communications passing on a military cable to the Khamchatka Peninsula Halibut was equipped with a deep diving chamber, fully in view on the submarine's stern. The chamber was described by the US Navy as a "deep submergence rescue vehicle". The truth was that the "rescue vehicle" was welded immovably to the submarine. Once submerged, deep-sea divers exited the submarine and wrapped tapping coils around the cable. Having proven the principle, USS Halibut returned in 1972 and laid a high capacity recording pod next to the cable. The technique involved no physical damage and was unlikely to have been readily detectable.

The Okhotsk cable tapping operation continued for ten years, involving routine trips by three different specially equipped submarines to collect old pods and lay new ones; sometimes, more than one pod at a time. New targets were added in 1979. That summer, a newly converted submarine called USS Parche travelled from San Francisco under the North Pole to the Barents Sea, and laid a new cable tap near Murmansk. Its crew received a presidential citation for their achievement. The Okhotsk cable tap ended in 1982, after its location was compromised by a former NSA employee who sold information about the tap, codenamed IVY BELLS, to the Soviet Union. One of the IVY BELLS pods is now on display in the Moscow museum of the former KGB. The cable tap in the Barents Sea continued in operation, undetected, until tapping stopped in 1992.

During 1985, cable-tapping operations were extended into the Mediterranean, to intercept cables linking Europe to West Africa. (30) After the cold war ended, the USS Parche was refitted with an extended section to accommodate larger cable tapping equipment and pods. Cable taps could be laid by remote control, using drones. USS Parche continues in operation to the present day, but the precise targets of its missions remain unknown. The Clinton administration evidently places high value on its achievements, Every year from 1994 to 1997, the submarine crew has been highly commended.(31) Likely targets may include the Middle East, Mediterranean, eastern Asia, and South America. The United States is the only naval power known to have deployed deep-sea technology for this purpose.

Miniaturised inductive taps recorders have also been used to intercept underground cables.(32) Optical fibre cables, however, do not leak radio frequency signals and cannot be tapped using inductive loops. NSA and other Comint agencies have spent a great deal of money on research into tapping optical fibres, reportedly with little success. But long distance optical fibre cables are not invulnerable. The key means of access is by tampering with optoelectronic "repeaters" which boost signal levels over long distances. It follows that any submarine cable system using submerged optoelectronic repeaters cannot be considered secure from interception and communications intelligence activity.

Re:Interesting note/errata (2, Interesting)

Alphanos (596595) | more than 10 years ago | (#7688277)

Disclaimer: I have not read the article since I don't know enough physics yet to be able to understand its significance:).

That said, I got the impression from the post that this could somehow be beneficial to quantum cryptography. If I understand correctly, the idea behind quantum cryptography is that as long as you have a direct optical line to whoever you're transmitting to, it is physically impossible for undetected eavesdropping to occur. This is because the nature of the system is such that a single observation of the signal will change it in such a way that it cannot be reconstructed. Perhaps advances in our understanding of light will allow this to function over the internet, where we don't have direct lines to everyone we want to transmit to.

Re:Interesting note/errata (1)

segment (695309) | more than 10 years ago | (#7688323)

Because an eavesdropper cannot accurately measure the bit's value using both of these competing standards, the only parties who can know the value of a string of such bits are the sender and receiver. And since an outsider measuring the system disturbs it, the sender and receiver also know whenever their line has been tapped.

In fiber connections typically when a line is spliced connection is cut. According to historic sources, quotes, etc., the NSA managed to cut through fiber, get a tap in, without causing any flux or attenuation. First I would think some form of either mirroring or perhaps the use of a gem diamond, etc., but there would have to be some flux somewhere along the line, unless of course they hit up some of the repeaters or junctions in order to accomplish their goal. Think about a direct line of sight clearly... Even with Quantum crypto your line of sight is passing through channels, equipments, and if the NSA managed to break that light, sniff keys, AND THE CIPHERTEXT, etc., using a quantum computer themselves (the eavesdropper(s)), they'd be able to reconstruct a message (perhaps), maybe even using a distributed quantum network.

Strangely I wish I had this link up for Los Alamos' Quantum crypto labs [lanl.gov] but it looks like it was taken down.

So long as the parties on both ends use their key only once and know that they are the only owners of this key -- a certainty which quantum crypto provides -- then they are guaranteed security. Source for italics is an older Wired Article [wired.com]

Re:Interesting note/errata (5, Informative)

benjamindees (441808) | more than 10 years ago | (#7688495)

That may be how traditional optical communications works. Quantum crypto, otoh, relies on the light being put in a certain polarization state by the sender. It's designed so that a stream of single photons go from sender to receiver; there can be no equipment in-between. If an intermediary views this photon en-route, it disturbs the polarization seen by the receiver. Because of the way the sender and receiver can agree on which photons were correctly measured, any aberrations (intercepted photons) are discarded. The most you can hope for is a denial-of-service.

Here's a better explanation [dartmouth.edu] than I can muster.

I thought it was to do with single photon (0)

Anonymous Coward | more than 10 years ago | (#7688419)

transmissions (or something like that). If the NSA received these photons instead of the intended receipient, the intended receipient would know (due to loss of signal) and would inform the sender to stop sending (actually, assuming some kind of handshaking protocol, the transmission would be stopped by either end).

Or is it to do with entangled photons? It's certainly not standard fibre optics as it's done at the moment.

IANACE

Re:Interesting note/errata (1)

FrostedWheat (172733) | more than 10 years ago | (#7688448)

That shift has forced the NSA to seek new ways to gather intelligence -- including tapping undersea cables, a technologically daunting, physically dangerous and potentially illegal task.

Hmmm ... didn't one of those undersea cables recently have a number of failures recently? Concidence?

Light RAM (4, Interesting)

Space cowboy (13680) | more than 10 years ago | (#7688214)

Sounds like you could use it similar to the initial version of electronic memory (sort of a digital delay line), if it could be harnessed.

A few hundred-thousandths of a second is an eternity(*) for a photon. That's actually pretty impressive :-)

Simon.

(*) Yes, for the pedants amongst us, I realise it's not actually an eternity. It's a figure of speech, for chrissake!

Re:Light RAM (-1)

cablepokerface (718716) | more than 10 years ago | (#7688319)

A few hundred-thousandths of a second is an eternity(*) for a photon. (*) Yes, for the pedants amongst us, I realise it's not actually an eternity. It's a figure of speech, for chrissake!

Could you explain why? Are you just talking about the distance that can be travelled in that timeframe?

Pedant Note: (-1)

Anonymous Coward | more than 10 years ago | (#7688348)

It's "Christ's sake."

Another article (4, Informative)

Quirk (36086) | more than 10 years ago | (#7688241)

BBC News [bbc.co.uk] has an article which speaks a bit more to Quantum crytography.

"Quantum cryptography might provide very secure forms of electronic encryption, because the process of eavesdropping on an electronic message would introduce errors in the message, garbling it."

"This would allow you to exchange a key on a public channel, but whereas any classical system can be broken by an eavesdropper, in quantum cryptography you would always find out if someone was looking at your message," Professor Zubairy told BBC News Online."

better than quantum crypto (1)

segment (695309) | more than 10 years ago | (#7688344)

http://www.nytimes.com/2001/02/20/science/20CODE.h tml

The New York Times, February 20, 2001
The Key Vanishes: Scientist Outlines Unbreakable Code

By GINA KOLATA

A computer science professor at Harvard says he has found a way to send coded messages that cannot be deciphered, even by an all-powerful adversary with unlimited computing power. And, he says, he can prove it.

If he is right, and he does have some supporters, his code may be the first that is both practical and provably secure. While there are commercially available coding systems that seem very hard to break, no one can prove that they cannot be cracked, mathematicians say.

In essence, the researcher, Dr. Michael Rabin and his Ph.D. student Yan Zong Bing, have discovered a way to make a code based on a key that vanishes even as it is used. While they are not the first to have thought of such an idea, Dr. Rabin says that never before has anyone been able to make it both workable and to prove mathematically that the code cannot be broken.

"This is the first provably unbreakable code that is really efficient," Dr. Rabin said. "We have proved that the adversary is helpless."

Dr. Richard Lipton, a computer science professor at Princeton, who is visiting this year at the Georgia Institute of Technology, said, "It's like in the old `Mission Impossible,' where the message blows up and disappears."

Someone who uses one of today's commercially available coding systems, Dr. Lipton explained, uses the same key -- mathematical formulas for encoding and decoding -- over and over. Eventually, they may be forced, perhaps by a court order, to give up the key. Or the key may be stolen. But with Dr. Rabin's system, the message stays secret forever because the code uses a stream of random numbers that are plugged into the key for encoding and decoding. The numbers are never stored in a computer's memory, so they essentially vanish as the message is being encrypted and decrypted.

Rest of article mirrored at Cryptome [cryptome.org]

Other Days, Other Eyes (5, Interesting)

Pond823 (643768) | more than 10 years ago | (#7688244)

Could "Slow Glass" be coming? Bob Shaw wrote about glass that could slow down light so that it took years to pass through and the effects it had on society in his 1972 book Other Days, Other Eyes. Anyone interested in this stuff should hunt down a copy.

Re:Other Days, Other Eyes (4, Interesting)

Otto (17870) | more than 10 years ago | (#7688502)

Interesting story, I grant you, but if such a thing existed, you'd have to wonder at the temperature the glass would reach after absorbing light for a few years. It'd be possible to do something similar to it using other methods, but I doubt the possibility of doing it using anything similar to the methods described in the book.

light fantastic ??? (1)

stormer131 (139091) | more than 10 years ago | (#7688248)

Why do you think any communications technology will be untapable ?

It doesn't matter what medium is used, there will always be a point of access for law enforcement or network testing / troubleshooting. Try and get something certified for use without it !

Remember the transmission medium is only part of the story !

More links (5, Informative)

prospero14 (233659) | more than 10 years ago | (#7688256)

More detailed articles about the research can be found here [hackensackhigh.org] or here [sciencenews.org] .

Larkin's article itself is here [lanl.gov] .

Any physics nerds want to explain it to us?

Re:More links (5, Informative)

Zog The Undeniable (632031) | more than 10 years ago | (#7688278)

The light beam is stored (in gas atoms) rather than stopped. It's a bit like sending an e-mail - you don't get the same electrons that were sent to you from the other person's computer, but the electrons that come down your telephone line/DSL/cable are identical in every respect.

Re:More links (1, Informative)

Anonymous Coward | more than 10 years ago | (#7688420)

well, any one electron is in a sense identical to any other.

but there's a stronger concept at work in this light thing too, indistinguishability. Sometimes, the 'same' photon doesn't mean anything. actually, it never means anything. photon is the observed quanta, and you can only ever make the observation once, same with electrons.

Interesting note/errata (1)

segment (695309) | more than 10 years ago | (#7688280)

funny ass article quote...

Dr. Lloyd added, "Who ever thought that you could make light stand still?"

Possible responses:

Mulletboy: Hell Bobby Jo 'an I do it all da time we juss turn on dat dag gon lite dare and it don move a noggin

Psychologist: Well the light has to be willing to move itself you know

Moses: God saith it so Let there be light

Dalai Lama: The light suffers in this state. It learns compassion it is enlightened

k let me actually get a life and some sleep

In Soviet Russian traffic... (-1)

Anonymous Coward | more than 10 years ago | (#7688263)

Light stops YOU!

Serious! (2, Funny)

glenebob (414078) | more than 10 years ago | (#7688266)

This may prove to be a ray of inspiration for dim wits everywhere, beamed from the heavens to shed a new light on these dark times! Don't take it lightly. How we use this enlightenment will be a reflection on us all.

Altogether now: *grrooaaan*

If we stopped light, (1)

beyonddeath (592751) | more than 10 years ago | (#7688274)

wouldnt this mean that we have already gone faster than the speed of said light. i mean i think my car goes faster than 0m/s right? what implications would this have?

Re:If we stopped light, (2, Informative)

epsilon720 (307234) | more than 10 years ago | (#7688308)

That just means that if you were, in fact, able to drive your car through their rubidium medium, it might produce somthing akin to cherenkov radiation, another example of massive particles traveling faster than c/n.

Re:If we stopped light, (2, Informative)

trentblase (717954) | more than 10 years ago | (#7688325)

I think you're not supposed to be able to go faster than light under the _same conditions_. If someone used forward and backward control beams to time-vary your Rabi-frequencies, I doubt you'd be going anywhere fast.

Re:If we stopped light, (1)

cpghost (719344) | more than 10 years ago | (#7688436)

What about blackholes? Light can't escape, not because it is slowed down or halted, but because the space is distorted. Did they create a small artificial blackhole to trap light? :-)

Darn darn darn (5, Funny)

pikkumyy (445891) | more than 10 years ago | (#7688296)

Why were there no pictures of this stopped light? .. oh wait

Speed of light inconsistencies (1)

azmaveth (302274) | more than 10 years ago | (#7688363)

If the speed of light changes, what does this mean for using the speed of light as a measuring rod for interstellar distances? Sounds to me like we'd better rethink the size of our universe. Feel free to correct me (as if I need to say that on /.), but if the universe is truly expanding, doesn't that mean the interstellar gasses and debris have also been "thinning"? How can we be sure that this expansion hasn't affected the speed of light?

Deja Vu?? (1)

UezeU (731858) | more than 10 years ago | (#7688370)

"Our experimental apparatus used to demonstrate this effect is shown in Figure 2A. A magnetically sheilded 4 cm cm long 87Rb cell is maintained...." 2nd page, 2nd column of Lukins paper The 87Rb is in vapor form... Sound like a vacuum tube to anyone???

SF story with slow-light windowpanes? (5, Interesting)

pnagel (107544) | more than 10 years ago | (#7688376)

I once read an SF short story that featured windowpanes which light took decades to pass through - thereby letting you look at the past.

The story included the poignant scene of the protagonist looking out at his wife and child playing in the garden - but they had died 15 years earlier. The character used to hang around near the windows, hoping for glimpses of his dead wife, because he, of course, had no control over when he saw her; the windows would "replay the past" in strict linear sequence.

Does anyone know the name & author of the story?

In the story, the windowpanes were made of optical fibre nanotubes that were so tightly coiled up in the windows that the windows could accomodate tubes a few light-years long.

This research suggests more feasibly ways of doing this, though.

^^Very Interesting, should get modded up^^ (1)

John Seminal (698722) | more than 10 years ago | (#7688417)

That is a fascinating idea, that by slowing down light you can look into the past. But there is a ramification, that if this would work then everything is pre-determined. And would you only get to look back on what that light ray would have been near, or would it not matter. Either way, it is fascinating.

Re:^^Very Interesting, should get modded up^^ (2, Insightful)

pnagel (107544) | more than 10 years ago | (#7688443)

What do you mean by "then everything is pre-determined?" In one sense, obviously the previse nature of the past events of the past you see are pre-determined, because they already happened. Or do you mean that viewing the past confirms a Deterministic view of the universe? How so?

Re:^^Very Interesting, should get modded up^^ (0)

John Seminal (698722) | more than 10 years ago | (#7688475)

If for example, you picked a time 10 years ago, and looked at a person from that time, one might think that there were many possibilities of what could happen in those 10 years to that person; like a tree, with each leaf being a possiblility of today's existance. That makes sence to the person 10 years in the past, they think they are making choices.

What the original post said was someone had the idea of slowing down time to look back in the past. There is only one route to today's future, or should I say only one route to the past. No choices. Going backwards, you could connect all the dots. There are no choices. Perhaps our idea of freedom and choice is just an incorrect way at looking at time.

Re:SF story with slow-light windowpanes? (4, Informative)

LordLucless (582312) | more than 10 years ago | (#7688460)

Bob Shaw, Other Days, Other Eyes. A poster above mentioned it.

Greatest breakthrough ever? (1, Informative)

psychofox (92356) | more than 10 years ago | (#7688396)

According to the Slashdot summary, it is apparently possible to destroy energy!!! Issac Newton may turn in his grave...

This is nothing new ! (1, Funny)

Anonymous Coward | more than 10 years ago | (#7688401)

Stop lights has caused my whole car, not just the head and tail lights, to a complete stand still, even for minutes, one my way to work for decades !

eavesdropping? (0)

Anonymous Coward | more than 10 years ago | (#7688410)

this will hopefully help the development of quantum computers and ways to communicate over long distances without being eavesdropped on."


Uhhh, how about only using VoIP if it's encrypted?

interesting stuff.. (-1, Troll)

Anonymous Coward | more than 10 years ago | (#7688418)

you all suck.
you're all nerds.
you're all gay.
you all live in your mom's basement smoking weed and eating cheetos.
you couldn't get laid if a woman dropped on top of you and tore your pants off.

Re:interesting stuff.. (-1, Troll)

Anonymous Coward | more than 10 years ago | (#7688485)

you all suck.
I suck dick. I don't know about the rest of the Slashdot community.

you're all nerds.
I'm smart, if that's what you mean. Most others on Slashdot are, too.

you're all gay.
In fact, I am! Everybody else, not so much.

you all live in your mom's basement smoking weed and eating cheetos.
The only part that's remotely correct about that is smoking weed.

you couldn't get laid if a woman dropped on top of you and tore your pants off.
If everyone on Slashdot is gay, why would they want to have sex with a woman in the first place? Plus, man-on-man action is at least fifty times hotter.

Freezing Light BS (1, Funny)

TheDredd (529506) | more than 10 years ago | (#7688425)

Ha! if they were able to freeze light, where are the pictures of the stationary beam of light floating in the air!!
Come on guys do you honestly think we will believe that in this day and age??

Is brief really very long time for the Photon? (5, Insightful)

leoaugust (665240) | more than 10 years ago | (#7688451)

have been able to stop light for a very brief period of time
a very brief period of time ? .. I think it depends on what perspective you look at it from.

I am just building my reasoning backwards. To understand what happens to the Photon when it stops, let's first see what happens to the photon when it moves at - well - the speed of light.

From the quickest reference I could dig thru [wired.com] http://www.wired.com/wired/archive/6.07/es_warp.ht ml?pg=3&topic=

Einstein also predicted that time itself must slow down for objects in motion.
The faster you move, the slower your clocks would appear to tick - relative to someone watching from a remote location. If you could actually reach light speed, time would crawl to a stop. It's wildly counterintuitive, but experiments have proved it true.

So, the faster the photon moves the slower the clocks would appear to move. Then, I guess, the slower the Photon moves the faster the clock would appear to move. And when the photon STOPS, the clock must be moving INSANELY FAST. So how could it be a very brief period of time ? .. I think it is a very very very long period of time.

Guess, it all depends on which perspective you are looking at, and how you are measuring time ...

Faster than light (1)

Eudial (590661) | more than 10 years ago | (#7688507)

Aand running faster than light suddenly isnt that stunning any more.

Isnt Speed of light linked to time? (2, Interesting)

PaulGrimshaw (605950) | more than 10 years ago | (#7688517)

I thought speed of light was linked to time? If this is the case, what happens to time in this experiment? Apologies if I am being a twat.

Paul.

felonious softwar gangsters hoping to freeze time? (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#7688518)

buy striking DOWn UN motion to promote gnu/free stuff to developing nations.

they seem to have hit the eXPanding georgewellian fuddite corepirate nazi execrable moretoll bullock. it's really just a sintax (t)error, whereas the fuddites' infactdead process, keeps replacing the 'one' in one wwworld, with won.

lookout bullow. continued pretending does not help/makes things worse?, if that's even possible.

united? nations? just won?

consult with/trust in yOUR creators.... the light itself, is not frozen, but does does function just as well in extremely low temperatures, all the way down to mynuts won? see you there?
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