They say it´s been published on Nature...

__________________
There’s probably no God. Now stop worrying and enjoy your life.

Hum,
by going faster than light you could possibly go backwards in time,
but i`m not sure that that this would make this a new story.

__________________
`Irony` actually does mean `metal like`...

This is a dramatic example of a case where an absorptive medium can transmit waves with a group velocity exceeding c. In such a medium, the complex refractive index has a non-zero imaginary component.

It's the pulse shape that goes faster than the speed of light, although it still can't actually be used to transmit information.

You can read more about it under group velocity at Wikipedia.

Cheers -- Sylas

There has to be something faster than light

__________________
Nikon D200
Nikon D50
Nikon 300mm F4D ED-IF AF-S
Nikon 50mm F1.8
Sigma 70-200mm F2.8EX DG Macro
Sigma 24-70mm F2.8EX DG Macro

That article is 7 years old!

__________________

Well I guess that shoots this in the foot.

__________________
Gimme a minute to read through Jay's latest observations...

Hum,
these temporal paradoxes still makes me laugh though...

__________________
`Irony` actually does mean `metal like`...

Doesn't that prove that it works?

__________________
"It's turtles all the way down."

I´ll pay attention to the small letters next time... And stop trusting Slashdot.

__________________
There’s probably no God. Now stop worrying and enjoy your life.

I'd be more impressed if it were -7 years old.

or 7 years anti-old??

__________________
"It's time to receive our missions from The Head."

I'll just stick to basics. No particle has ever been observed traveling faster than light in the (neutrino sea/ vacuum), none, nada, nix, nope, and ain't gonna happen if you intend on keeping SR, Hendrik Von, and Albert happy, either...not to mention Ken G, Tim T., Grey, Celestial Mechanic, Antoniseb, SpacemanSpiff,...and a host of others. pete

__________________
A third rate theory forbids
A second rate theory explains after the fact
A first rate theory predicts...A. Lomonosov

Sylas, you are right of course! The give away passage.........

came right at the first page. Why else should you begin to talk in that way about a light puls!! Obviously the work of a science reporter who did only grasp part of what was served to him at Princton....
As I have also forgotten more than half of it since I learnt it, I will go and study the wikip. article.............thanks!

the wikip. article seems to be a little faulty
first group velocity is defined as the speed of the wave (group) envelope
from that what follows you can infer, that a medium which is apt to yield a greater than c group velocity would neccesserily alter the shape of this envelope and by that very fact invalidating the worthiness of the definition of group velocity as given at the outset.

Don't be silly. I'd be delighted to find out that we could travel or communicate faster than light. I just think that it's fantastically unlikely.

__________________
Conserve energy. Commute with the Hamiltonian.

so, you would be delighted then, to see causality and logic be blown to smithereeeeens......................shame on you, shame i say!

To answer semi-seriously, though, obviously if superluminal movement is possible, it can't really result in serious problems for causality, or we'd see those effects already. It would certainly mean a serious revision (or maybe even a complete scrapping) of relativity, but I'm sure that some bright person would sort it all out and figure out why the universe hasn't vanished in a puff of acausality and illogic.

__________________
Conserve energy. Commute with the Hamiltonian.

Yeah, but the article hasn't been written yet!

Grey, i seem to have reached the sclerotic age, were i would be unable to let go of the strict "the Lorenz Transformations are Fundamental" axiom (hardwired in my axons)!
There were bytheby better takes at offsetting the c-vac.=const. law. One group claimed (claimes?) to having proven that the tunnelling of photons "didn't take time" ((some sort of smile))............I don't know, how they haved fared since then with that..........anyway! It would at least look to me more promissing to seek small deviations from the pure law in the quantum realm, than to go on the lookout for something as outlandish as a warp scale correction of "c=c"

hahahahahahahahahahahahahahahahahahahahahahahahaha hahahahahahahahahahahahahahahahahahahahahah

(i did smile allready today (see post above), but that one saves my day, Sam5! (at 2332 lokal time.............. just in time))

evidence of time-travel