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Scientists Speed up Light

CowboyNeal posted more than 9 years ago | from the breaking-the-law dept.

Technology 416

An anonymous reader writes "With off-the-shelf components, scientists have managed to speed up light beyond the 'universal' constant of c, or roughly 300 million meters/sec. This, and the previous ability to slow light down could shake up the telecom world, according to the story at Science Blog." Also, all those posters with 186,000 miles per second as a speed limit need to be amended. At least entropy is still around!

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Overhyped as always (5, Informative)

trip11 (160832) | more than 9 years ago | (#13362222)

Everyone say it together with me: "Phase velocity vs Group velocity" There are no photons in this experiment that are traveling faster than the speed of light. Only collections of them that 'appear' to be doing so. Think of this as an example: I space people out in a line, each of them two light minutes apart from the people next in line (all at rest with respect to each other). Now I go about talking to them and informing them of my plan. At 12:00 the first person waves, at 12:01 the second person waves, at 12:02 the third person waves, and so forth. My "wave" is propogating, therefore, at twice the speed of light. This is the same thing that this experiment is doing more or less. By spending extra time setting up the experiment, you can make it appear that a light pulse travels faster than c, but like my "wave" it is only an appearance.

Re:Overhyped as always (1)

Doppler00 (534739) | more than 9 years ago | (#13362286)

The important question we all want to know is does this mean reduced ping times? Seriously though, it takes 100ms or more for a signal to reach half way around the globe. Anything that can speed that up would be much appreciated.

I read somewhere that entangled photons don't allow faster than light information transfer either. Is there any hope for faster than light information transfer?

Re:Overhyped as always (2, Informative)

Anonymous Coward | more than 9 years ago | (#13362378)

Information transfer *is* what's limited by c. It then *follows* that a particle cannot travel faster than light, but that's a simple case. In general the limit applies to an experiment only if that experiment could be used to transfer information.

Re:Overhyped as always (2, Funny)

SmithG (688785) | more than 9 years ago | (#13362288)

Yes - of course - but does that have any bearing on the use of this technology in transmitting pornography?

Re:Overhyped as always (0)

Anonymous Coward | more than 9 years ago | (#13362291)

I don't quite see what you mean.

Re:Overhyped as always (5, Insightful)

justanyone (308934) | more than 9 years ago | (#13362326)

Mod parent UP.

Information flow (see: Steven Hawking's theories) cannot propogate at faster than the speed of light, or causality is violated and we have (dead virgins/future grandfathers) all over the place.

All 4 basic forces: electromagnatism, gravity, strong nuclear, and weak nuclear (not Nukular; bite me, George) forces propogate at the speed of light in their reference frame. If we switch frames we're not fooling anyone; if we preposition information we're not watching causality violations.

This kind of story is quite irritating, not due to the actual achievement involved (playing with light propogation is actually very cool geek-cred stuff), but the overhype and miscommunication to all the laypersons out there who just go, "Yup, that's an 'oops', they said it was a law and now it ain't. I guess evolution might not really be true, dad-gummit, I don't trust me none o' dem smarty pants anyway."

Re:Overhyped as always (1)

justanyone (308934) | more than 9 years ago | (#13362344)

Oops, should have spell checked myself, Sorry, that's "electromagnetism". At least I know when I'm wrong, though. Mostly. If you don't listen to my wife. Mostly.

Re:Overhyped as always (-1, Troll)

Anonymous Coward | more than 9 years ago | (#13362482)

You are a Faggot. What does W have to do with this? And everyone is tired of pussies like you insulting people that have a regional dialect. If you understand what they mean, does it matter if their vernacular is different than yours? Do you also make fun of immigrants and people with speech impediments? Like my hairy Republican nutsack.
I am guess ing you hate Republicans because you have a lot of education, feel superior to others, yet you make very little money. So get in your 1984 Corolla and drive to hell.

Re:Overhyped as always (4, Funny)

Raul654 (453029) | more than 9 years ago | (#13362396)

...or causality is violated and we have (dead virgins/future grandfathers) all over the place

"And so the Trekkies were executed in the mannor most befitting virgins - thrown into volcanoes" - Futurama

I never realized there might be a corollation!

Fuck you, elitist piece of shit (-1, Troll)

Anonymous Coward | more than 9 years ago | (#13362517)

Just couldn't keep the politics out of it because you're an obsessed fucking dweeb.

What an asshole. Listen, when some redneck pops your ass for your for-shit attitude, i'm going to piss on your grave. But probably not. Like all the other metrosexual (hah) leftist losers, you behave like a good little servant when faced by a real redneck. Scared shitless, i'm sure. It's only here where your mouth runneth over.

Have a nice day.

Not quite (5, Informative)

pauljlucas (529435) | more than 9 years ago | (#13362518)

All 4 basic forces: electromagnitism, gravity, strong nuclear, and weak nuclear ... forces propogate at the speed of light in their reference frame.
They propagate at the speed of light in all reference frames, i.e., the speed of light is the same to all observers.

(However, including the nuclear forces is moot since they have no influence nor can they be observed outside the nucleus of an atom.)

Re:Overhyped as always (2, Funny)

Tablizer (95088) | more than 9 years ago | (#13362356)

My "wave" is propogating, therefore, at twice the speed of light..... you can make it appear that a light pulse travels faster than c, but like my "wave" it is only an appearance.

This is what happens when you let marketing into the physics department. As long as the customer believes it.... :-)
         

Re:Overhyped as always (1)

FFFish (7567) | more than 9 years ago | (#13362373)

Or... correct me if I'm wrong! ...

Being in a bank lineup, slowly progressing toward the front of the line during the lunch rush hour, you pass a bag of Mentos forward to share. While you (a photon) move slowly, the Mentos move (the information) moves quickly.

Or like a wave on the ocean: individual water molecules drift in the currents at a slow speed, while the wave moves quite rapidly across the water. Photons versus waveforms.

Re:Overhyped as always (1)

Tango42 (662363) | more than 9 years ago | (#13362533)

Yes, just the other way round... ish.

Re:underread as always (0)

nomadic (141991) | more than 9 years ago | (#13362403)

Everyone say it together with me: "Phase velocity vs Group velocity"

No.

Re:Overhyped as always (5, Informative)

lgw (121541) | more than 9 years ago | (#13362419)

There are some experiments in which photons are travelling faster than "the speed of light", because c is defined in a vacuum, and a vacuum is not the lowest impedance available.

Even in a vacuum, light doesn't travel as photons for the entire journey (at least, if you believe in quantum). Light spends some of its time as electron-positron pairs which exist very briefly, before annihilating to product a new photon. As the electron-positron pair travels slower than the speed of light, light in a vacuum (which is how we've defined c) travels slighty slower that the speed of a photon.

When you shine a light between very closely spaced conductive plates, that reduces the available "wavelengths" of the electron-positron pairs (I don't like that terminaology, but it makes the temporary electron-positron pairs less likely to occur), so the light spends more time as photons. Therefore light is travelling faster than "the speed of light".

But not really, it's just that c is standardized on the wrong empirical constant. What you care about is the speed of photons, not the speed of light in a vacuum.

Re:Overhyped as always (5, Informative)

exp(pi*sqrt(163)) (613870) | more than 9 years ago | (#13362425)

Don't explain it. Show [netspace.net.au] it!

MOD THIS UP UP UP! (1)

liquidpele (663430) | more than 9 years ago | (#13362544)

that link helped explain a lot, thanks.

Re:Overhyped as always (0)

Anonymous Coward | more than 9 years ago | (#13362443)

Neither your response nor the original article gave me enough information to conclude what you or the article suggested were true.

Most of the message appeared to be written before I read it, but I'm not certain of that.

Re:Overhyped as always (0)

Anonymous Coward | more than 9 years ago | (#13362456)

That reminds me of something I've always wondered about. Could you make information travel faster than the speed of light if you could fabricate a material with a Poisson ratio such that its incompressibility required a local speed of sound greater than that of light?

Re:Overhyped as always (1)

conJunk (779958) | more than 9 years ago | (#13362475)

Many thanks- as someone who doesn't know much about physics other than what I can get from books like In Search of Schroedinger's Cat, it's always really cool to see something explained clearly and cleverly.

My main question the article didn't answer was "how does the process work?", and you've not only shed light on the Stimulated Brillouin Scattering, but done so in a way that accessible to me, a non-physics person.

thanks!

Re:Overhyped as always (0)

Anonymous Coward | more than 9 years ago | (#13362479)

What else would you expect but a sensationalist headline?

This is slashdot, after all.

So it was just a good idea... (0)

Anonymous Coward | more than 9 years ago | (#13362226)

...after all.

warp speed (4, Funny)

longdead (860403) | more than 9 years ago | (#13362227)

but can they achieve warp speed yet?

Re:warp speed (0)

Anonymous Coward | more than 9 years ago | (#13362392)

Film at 11

Re:warp speed (1)

Nuclear Elephant (700938) | more than 9 years ago | (#13362525)

More importantly, can they achieve infinite probability drive, or generate an S.E.P (Somebody Else's Problem) Field.

Re:warp speed (1)

pauljlucas (529435) | more than 9 years ago | (#13362538)

Warp speed's too slow. They need to achieve ludicrous speed!

1st pos7 (-1, Offtopic)

nortonantivirus (908969) | more than 9 years ago | (#13362228)

thats awesome now maybe my dial up will be faster

Re:1st pos7 (0)

Anonymous Coward | more than 9 years ago | (#13362297)

Holy shit -- a subscriber to Slashdot with a terribly unsuccessful attempt at a first post.

Dude, why are you wasting your money?

Re:1st pos7 (0, Offtopic)

nortonantivirus (908969) | more than 9 years ago | (#13362318)

give me a few miliseconds of credit

Re:1st pos7 (1)

donaldgelman (730958) | more than 9 years ago | (#13362348)

maybe if he had faster dial-up then that would have actually been a first post.

Re:1st pos7 (0, Offtopic)

nortonantivirus (908969) | more than 9 years ago | (#13362484)

i'm bored at work and sitting on a 15Mb connection. the dial up is free.

repost? (2, Informative)

rkruse (837943) | more than 9 years ago | (#13362231)

Hasn't this already been done before?

Re:repost? (1)

Tablizer (95088) | more than 9 years ago | (#13362407)

Hasn't this already been done before?

Are you saying dups travel into the future by going faster than c? Hmmm, the new science of dupology. Let's see, if two dups leave two different keyboards at the same time, and one dup can reach /. before the first dup is finished being typed, then the first dup is published but the second dup is not yet, unless it then goes faster than light and beats the first dup to /. such that it gets published before the second dup, and now they are both published. This is why Oracle transaction A.C.I.D. won't work on Enterprise when they enter warped space-time and went out of business in the 22nd century, beaten by DBMS vendors who got transactions to work in warped space-time. I think I've had too much coffee.
       

MY FRIST POST TRAVELS FASTER THAN LIGHT (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#13362232)

or does it?

Ludicrous Speed! (5, Funny)

Anonymous Coward | more than 9 years ago | (#13362233)

Were they able to speed it up to ridiculous speed, or perhaps even plaid?

First Prime Factorization Post (1)

2*2*3*75011 (900132) | more than 9 years ago | (#13362235)

c = 299792458 m/s = 2*7*73*293339 m/s

Obnoxious pop-ups.... (0, Offtopic)

MilenCent (219397) | more than 9 years ago | (#13362236)

...that even show up under Firefox. Thanks, "Science Blog!"

Re:Obnoxious pop-ups.... (1)

magicchex (898936) | more than 9 years ago | (#13362284)

Not with the easily obtained and third most popular extension NoScript [mozilla.org] .

Re:Obnoxious pop-ups.... (0)

Anonymous Coward | more than 9 years ago | (#13362366)

.. and on my firefox, Adblock already had
*.casalemedia.com/*
and
pagead*.googlesyndication.com/*

in its blocklist, so I didn't need NoScript. I must take a look at noscript though....

Re:Obnoxious pop-ups.... (0)

Anonymous Coward | more than 9 years ago | (#13362301)

upgrade to the alpha 2 release and you won't get popups - firefox 1.5 is gonna be great!

Re:Obnoxious pop-ups.... (0)

Anonymous Coward | more than 9 years ago | (#13362521)

I'm running Firefox 1.0.4 on linux with privoxy, and the page looks quite plain with no popups or ads at all.

Re:Obnoxious pop-ups.... (0)

Anonymous Coward | more than 9 years ago | (#13362545)

Ditto, but Firefox 1.0.6.

Wish we had this 5 years ago... (0)

CmdrTaco on (468152) | more than 9 years ago | (#13362239)

Hello, Future?

Future: Yes?

Don't vote for Bush.

Finally (5, Funny)

cloudkj (685320) | more than 9 years ago | (#13362241)

About time they sped Light up. Now they better start working on speeding Dark up or else the force will be unbalanced....

Re:Finally (1)

KitesWorld (901626) | more than 9 years ago | (#13362374)

Meh, i seem to recall that Dark was already faster than light.





No, don't look confused - it was a bad joke to begin with. The film I'm reffering to is 'Neverending Story II', not star wars. Sorry. >_

So Einstein was wrong? (0)

Anonymous Coward | more than 9 years ago | (#13362243)

Seems like some fundamental principles of time-space are being violated.

Perhaps there is something wrong the the measuring instruments?

While they're at it, perhaps they could tell us the speed of gravity.

FTFA (1)

NoData (9132) | more than 9 years ago | (#13362283)

They were also able to create extreme conditions in which the light signal travelled faster than 300 million meters a second. And even though this seems to violate all sorts of cherished physical assumptions, Einstein needn't move over - relativity isn't called into question, because only a portion of the signal is affected.

Vague, but like others before have conjectured, probably a change in phase velocity.

Re:So Einstein was wrong? (0)

Anonymous Coward | more than 9 years ago | (#13362399)

The speed of gravity is the same as the speed of light. Several experiments have added evidence to that.

Bet you any money... (2, Informative)

gowen (141411) | more than 9 years ago | (#13362244)

... it's "only" the phase velocity. This has been done before, and, since information is carried at the group velocity, there aren't any serious "light-cone" repercussions for Einsteinian limits on causality.

Re:Bet you any money... (1)

dlt074 (548126) | more than 9 years ago | (#13362333)

"light-cone" FINALLY! i've been looking for something to go with my cone of cold [thottbot.com] ! mages rejoice!
/dance

good nothing (-1, Troll)

Anonymous Coward | more than 9 years ago | (#13362245)

first post

not past the absolute limit I think (1)

asjk (569258) | more than 9 years ago | (#13362246)

IINAP but I think that althogh the scientists speeded up light in this particular medium that does not mean that the absolute limit will be change. Comments?

Re:not past the absolute limit I think (-1, Flamebait)

Anonymous Coward | more than 9 years ago | (#13362342)

I'd like to comment on your pathetic attempt to karma whore. You're not insightful or interesting, rather you are redundant for stating the obvious question brought up by this experiment.

You are a fucking stillbirth. But IINAP, right?

Re:not past the absolute limit I think (1)

vertinox (846076) | more than 9 years ago | (#13362492)

IINAP but I think that althogh the scientists speeded up light in this particular medium that does not mean that the absolute limit will be change. Comments?

Light is an absolute limit, but the limit depends on where you are in the Universe and how fast you are traveling from point A to point B. Or rather it would be better to say "Sometimes laws of physics bends depending where you are and how fast you are traveling." or at least bend your observations of the laws of phsyics.

I mean if you were traveling near the speed of light pretty close to a black hole then perhaps your observation of the speed of light would be quite different than those walking around on earth...

I mean if you were traveling at the speed of light... How would that affect instruments that produce light? Would you just not see the light hitting your eyes or light emmiting objects travling as fast as light have some type of doppler affect since the light behind it is more of a trail and the light infront of it just balls up since the light emmitting object is travling as fast as the light it produces...

Re:not past the absolute limit I think (0)

Anonymous Coward | more than 9 years ago | (#13362508)

I think you mispronounced 'sped'.

Before people get too excited (1)

Mukaikubo (724906) | more than 9 years ago | (#13362251)

"And even though this seems to violate all sorts of cherished physical assumptions, Einstein needn't move over - relativity isn't called into question, because only a portion of the signal is affected."

So no, this isn't the massive, century-defining, warp-drive-enabling experiment you all are dreaming for. Sorry. It's neat, and it'll probably have cool applications though. And that should be enough.

Re:Before people get too excited (1)

Whumpsnatz (451594) | more than 9 years ago | (#13362539)

But what the heck does that mean? "Only a portion"? There's nothing in the article to explain how they determined that it was "faster than light", or why an FTL event would be irrelevant if it only affected a portion of the signal. Is this just another of those perception games, or did light actually go faster than it's assumed maximum?

Nothing too new... (5, Informative)

Space cowboy (13680) | more than 9 years ago | (#13362252)


There's more than one measure of the speed of light - the phase velocity and the group velocity. It's the group velocity that can't travel faster than c, the phase velocity is free to travel faster assuming dispersion is allowed. In any event, information travels at the speed of the group velocity, which is why the write-up mentions that Einstein ain't wrong just yet ("only a portion of the signal is affected").

If you look at this treatment of wave velocity [mathpages.com] , it's reasonably clear ([grin] - at least if you've done undergrad physics, but then in that case you'd know all about it anyway :-)

A good quote from the above link:

Unfortunately we frequently read in the newspapers about how someone has succeeded in transmitting a wave with a group velocity exceeding c, and we are asked to regard this as an astounding discovery, overturning the principles of relativity, etc. The problem with these stories is that the group velocity corresponds to the actual signal velocity only under conditions of normal dispersion, or, more generally, under conditions when the group velocity is less than the phase velocity. In other circumstances, the group velocity does not necessarily represent the actual propagation speed of any information or energy. For example, in a regime of anomalous dispersion, which means the refractive index decreases with increasing wave number, the preceding formula shows that what we called the group velocity exceeds what we called the phase velocity. In such circumstances the group velocity no longer represents the speed at which information or energy propagates.

The phenomena is also discussed in Feynman's Lectures on Physics ( vol 1, Chapter 48-6) in a bit more rigor - these books ought to be required reading of any physics undergrads :-)

Simon

here's an example... (5, Interesting)

jxyama (821091) | more than 9 years ago | (#13362312)

Not sure if it's 100% relevant, the example I remember from school is: Take a powerful spotlight and place an object in front of it. Now go, really, really far away and watch the shadow cast by the object on the wall. Further you go, more "magnified" its movement will be, i.e., since the spotlight will be bigger further away, waving an object across the face of the spotlight will move the shadow on the wall across greater distance. If the spotlight is powerful enough, you can extend the wall as far as you want and the shadow will move as fast as you want, even faster than the speed of light.

Note that no information is being transmitted faster than the speed of light in such a case. Shadow may traverse across the spotlight faster than the speed of light, but the actual information that creates the shadow is still transmitted at the epeed of light from the spotlight to the wall.

Re:Nothing too new... (1)

InsideTheAsylum (836659) | more than 9 years ago | (#13362314)

Can you explain that in layman's talk now? For a moment there I had a "rotational speed of toast" moment as you were talking about "regime of anomalous dispersion, which means the refractive index decreases with increasing wave number."

Re:Nothing too new... (2, Informative)

Geoff St. Germaine (819751) | more than 9 years ago | (#13362402)

Good post. I recall a lecture I had from a PhD from Los Alamos when I was doing my undergraduate degree about the group velocity exceeding c, but they could still not transmit information at that velocity. The information velocity isn't the phase velocity, but it isn't necessarily the group velocity either.

Re:Nothing too new... (1)

lessa (202328) | more than 9 years ago | (#13362447)

That's quite right. Phase velocities faster than the speed of light are not new. The "speed limit" concept does apply to the propagation of information, which occurs at the group velocity. However, if you read the abstract of the paper, Applied Physics Letters [aip.org] , you see that it is, in fact, the group velocity that has been adjusted in these experiments.

I am deeply dubious that this is truly a relativity violation, but everything I have read online seems to point in that direction. I plan to head to the local university library as soon as I get a chance, so I can read the full article.

Re:Nothing too new... (1)

AxelBoldt (1490) | more than 9 years ago | (#13362498)

There's more than one measure of the speed of light - the phase velocity and the group velocity. It's the group velocity that can't travel faster than c

No, both phase velocity and group velocity can exceed c. (The quote you give makes that point.) Signal velocity cannot, however. If it could, you'd have immediate time travel, according to special relativity.

Don't have to change the constant (4, Informative)

Azarael (896715) | more than 9 years ago | (#13362253)

When people have 'c' recorded, it's assumed that it's referring light in a vacuum and it's not messed around with. So the values can stay the same.

No big deal (1, Insightful)

Anonymous Coward | more than 9 years ago | (#13362258)

Please note that this result doesn't violate the second postulate of special relativity, because the "speed of light" > c being talked about here is only the phase velocity in a medium. One cannot use these optics tricks to transmit material or information faster than c.

Amazing what you can do with (1)

winkydink (650484) | more than 9 years ago | (#13362261)

a coffee-can exhaust and a NOSx kit

I predict ... (1)

AdamReyher (862525) | more than 9 years ago | (#13362264)

Cool. Now I'll be able to have conversations with people before words even come out of their mouth. Always wanted to do that ...

ooo... I know (1)

fbartho (840012) | more than 9 years ago | (#13362408)

That's like saying STFU when they open their mouths!

ob. fut. ref. (1)

EddieBurkett (614927) | more than 9 years ago | (#13362273)

Does this story count as an obligatory Futurama reference?

Cesium Chamber Experiment from Before (4, Informative)

vectorian798 (792613) | more than 9 years ago | (#13362276)

Is this really that new? This has happened before. Read here: CNN: Light can break its own speed limit [cnn.com]

And before we all start yapping, I quote from the (CNN) article:

This effect cannot be used to send information back in time," said Lijun Wang, a researcher with the private NEC Institute. "However, our experiment does show that the generally held misconception that `nothing can travel faster than the speed of light' is wrong.

Light that travels faster than the speed of light (1)

TarryTops (888130) | more than 9 years ago | (#13362279)

Funny title. It's like saying sound travels faster in water than speed of sound in water. (It's 1440m/s BTW)

Re:Light that travels faster than the speed of lig (1)

NaruVonWilkins (844204) | more than 9 years ago | (#13362437)

Isn't the speed of sound different in different water pressures?

Ob. Simpsons [mangled] Quote (1)

theGreater (596196) | more than 9 years ago | (#13362295)

Homer: In this house, we obey the laws of [physics].

Something's amiss here... (1)

mark-t (151149) | more than 9 years ago | (#13362303)

They were also able to create extreme conditions in which the light signal travelled faster than 300 million meters a second. And even though this seems to violate all sorts of cherished physical assumptions, Einstein needn't move over - relativity isn't called into question, because only a portion of the signal is affected.
Can someone explain to me how it could be that just because only "a portion" of the signal is affected, this does not violate what has been previously understood to be an absolute law of the universe? If even the tiniest fragments of information can be communicated across a distance in less time than it takes light to travel there, as near as I can see it would require a major rewriting of every physics book written in the last century.

Re:Something's amiss here... (5, Interesting)

PDAllen (709106) | more than 9 years ago | (#13362416)

Suppose you had a chain of people 3,000,000km long, and you had them do a Mexican wave. It'd take (a lot) more than 10 seconds to go from one end of the chain to the other because people don't react that fast.

Now suppose you gave each person a Bleepy Thing (tm) which you have sychronised beforehand so they go off at staggered intervals, the last one at the far end of the line 2 seconds after the first. You have the chain of people do its Mexican wave by standing as soon as their Bleepy Thing goes off. Wave velocity will be approximately 5c. There's no problem synchronising the bleepy things, just set them to go off at the right time intervals when they're all together in one place and then move them fairly slowly (like 100km/s is fine) to the right places in the chain.

So why doesn't that break relativity? Answer: the wave does not carry information that fast. In fact the only information you get from the far end of the wave is the time the bleepy things were set to go off at - which reached you much slower than light speed when the bleepy things were sent down the chain beforehand.

This is much the same trick just done with a light wave not a Mexican wave.

Makes for good headlines (1)

confusion (14388) | more than 9 years ago | (#13362325)

I have read this article everywhere I turn, on every news show I've watched today. Most of them are *NOT* portraying the "discovery" in its proper context.

Jerry
http://www.cyvin.org/ [cyvin.org]

Ooh, controversial! (1)

Bralkein (685733) | more than 9 years ago | (#13362340)

Is this really making the light waves go faster, or is it just anomalous dispersion? I heard in one of my Physics lectures that you can make something happen that looks like superluminal motion, and it caused a bit of controversy when someone did it, but it's not actually the wave that's moving faster than c - it's actually the wave envelope, which is related to the amplitude of the wave. I could try and explain, but I'd only make things confusing (if I haven't already!), so I have found some animations you can look at, see here [netspace.net.au] and here [csupomona.edu] .

On the other hand, if the light really is going faster than c, then I am thoroughly impressed!

Speed of light in OPTICAL FIBER (1)

mirth (38671) | more than 9 years ago | (#13362352)

They've increased the speed of light in optical fiber... Not a vacuum... (which is c).

In optical fiber, it's less than c. The posting makes too many fanciful assumptions.

http://en.wikipedia.org/wiki/Speed_of_light [wikipedia.org]

My Car. (1)

daviqh (906581) | more than 9 years ago | (#13362382)

And when can I get this speed for my car?

Lightspeed Brand Increases (1)

Citizen of Earth (569446) | more than 9 years ago | (#13362394)

What kind of horse shit is this?! We all know that they don't increase the speed of light until 2208.

Futurama (1)

StonedRat (837378) | more than 9 years ago | (#13362406)

Prof.: These are the dark matter engines I invented. They allow my starship to travel between galaxies in mere hours.

Cubert: That's impossible! You can't go faster than the speed of light.

Prof.: Of course not! That's why scientists increased the speed of light in 2208!

Cubert: Also impossible!

Well that bites... (1)

suitepotato (863945) | more than 9 years ago | (#13362414)

...I was hoping someone had finally done a quantum vacuum experiment speeding up the local speed of light within the experiment area. But nooooo...

It'll happen though. Eventually. Probably not untill Maxwell's original equations are restored and made sense of versus Heavyside's edits, but it'll happen.

Factor of three? (1)

hazzey (679052) | more than 9 years ago | (#13362417)

slow light down by a factor of three from its well - established speed c of 300 million meters per second

Doesn't that mean that they slowed it down by 900million m/s?

So they made light go backwards?

A question (0)

Anonymous Coward | more than 9 years ago | (#13362424)

Could some one explain this to me? I never quite understood it.

Suppose I throw one ball at a speed of .75c to my left, and one ball at a speed of .75c to my right. Then from the perspective of one ball, the other ball is traveling 1.5c, right? I know it's not, but why not?

Star Trekkies Unite! (1)

Tiger_Frost42 (881666) | more than 9 years ago | (#13362432)

At last! The creation of the warp core! Jump to original light speed, Mr. Scotty!

Futurama Quote (1)

chickuaua (908984) | more than 9 years ago | (#13362433)

Farnsworth: "And these are the dark matter engines. They allow my ship to travel between galaxies in mere hours." Cubert: "But that's impossible! You can't travel faster than the speed of light!" Farnsworth: "Of course you can't! That's why scientists increased the speed of light in 2208!"

Second Law of Thermodynamics (1)

E3nder (908983) | more than 9 years ago | (#13362434)

Actually, I believe that under some circumstances the second law of thermodynamics "breaksdown". http://www.newscientist.com/article.ns?id=dn2572 [newscientist.com]

Heard in the lab (1)

Tablizer (95088) | more than 9 years ago | (#13362436)

"What the...? Ah, fuck! I just saw my own ass in this funky scope. Gym time for me."

Finally the Question is answered (1)

Grand Facade (35180) | more than 9 years ago | (#13362441)

When I am traveling at the speed of light, I WILL be able to see where I'm going....

I won't believe the title until... (1)

sluke (26350) | more than 9 years ago | (#13362459)

I'll believe that information can be sent faster than the speed of light when I get the tipoff from myself in the future.

old news (0)

mogalpha (782997) | more than 9 years ago | (#13362464)

Check discover magazine, circa 1999 I think.

Speed of Kibbitz (0)

Doc Ruby (173196) | more than 9 years ago | (#13362477)

Good news travels at the speed of sound. Bad news at the speed of light. Rumor even faster.

High-performance microwaves (0)

Anonymous Coward | more than 9 years ago | (#13362490)

Now our food is ready before we cook it!

At least entropy is still around! (1)

rattler14 (459782) | more than 9 years ago | (#13362499)

mmm, some would disagree
http://www.cheniere.org/techpapers/GiantNegentropy .pdf [cheniere.org]

Before the flack comes. Yes, as we currently define "energy", there is no way to reverse entropy. It's all based on assumptions, and they may not always be correct.

Check it out, see what you think.

The funny part about this article.. (2, Interesting)

Rac3r5 (804639) | more than 9 years ago | (#13362512)

"A team of researchers from the Ecole Polytechnique Fédérale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light - both slowing it down and speeding it up - in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions.

"The US Defense Advanced Research Projects Agency (DARPA) considers it so important that it has been funnelling millions of dollars into projects such as "Applications of Slow Light in Optical Fibers" and research on all-optical routers."

I can do that. It's still wrong. (0)

Anonymous Coward | more than 9 years ago | (#13362522)

Given a signal source, a slotted waveguide and a detector, I can make it look like my signal travels faster than the speed of light. It really isn't though.

The problem lies in the assumptions that you make while doing the measurement. In the case of the waveguide experiment, you assume that the waves travel straight down the waveguide. You measure the wavelength and knowing the frequency, you calculate that the signal is going faster than the speed of light.

The assumption about the direction the waves is travelling is wrong though. As the frequency goes up, the waves tend to travel at an angle. What you measure therefore isn't the real wavelength, it's the distance between peaks along a non-perpendicular line.

I think these guys have fallen into the same trap.

In Soviet Russia (1)

mynickwastaken (690966) | more than 9 years ago | (#13362530)

The Light Speeds Up the Scientits.

Old Math Joke (0)

tiny69 (34486) | more than 9 years ago | (#13362542)

2 + 2 = 5

For large values of 2.
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