You know that saying...

[LegendKiller]

If you go any slower you will be moving backwards?

Now they have apparently broken the law of physics

If you go backwards you will move faster.


http://www.scienceblog.com/cms/lights-most-exotic-trick-yet-so-fast-it-goes-backwards-10590.html

[Airencracken]

Woah. 133754uC3.

[InfiniteNothing]

leetspub?
http://www.urbandictionary.com/define.php?term=133754uC3

[Airencracken]

actually it's leetsauce

[Houdini]

Nifty. I'm usually pretty good at conceptualizing this stuff. S. Hawking rocks, for instance. Plus his CD is cool. "The Mighty Stephen Hawking is a effing Quake Master," etc. From "A Brief History of Rhyme." :)

What I'm going to have to wrap my brain around tonight is how the pulse at the far end of the fiber gets there when it was sent from the other end. This implies reflection, intentional or otherwise. Or the fiber is fishy. But, in those conditions, dealing with those specific materials, who the hell knows. If I pour water into a straw, I don't expect an equal amount of water to shoot back at me as my first pour leaves the straw. Yeah, photons are much different, and I'm thinking something along the lines of forgetting about light as photons and thinking more along the lines of wave amplification/cancellation, but I'll have to think about it some more.

[InfiniteNothing]

actually it's leetsauce
I see your 133754uC3

And raise you a 133751(13

It's a cool refreshing 1337 flavored popsicle.

[Markel]

Wow. This one rates up there with entangled particles (http://whyfiles.org/shorties/133quantum_leap/).

[Kevster]

This does not surprise me at all. I work in the optical communications field, and I have had to deal with optical oddities quite a bit. I remember seeing someone who was not so smart write a letter at Maximum PC about how he was impressed that the mag had reported how IBM researchers had slowed down the speed of light to a virtual crawl (for light anyway). The letter writer stated that he was always a little disbelieving that Einstein's theory of relativity and how the speed of light was an absolute and was happy to see Maximum PC reporting such important breakthroughs. Of course, the editorial staff had to correct him saying that Einstein's theory was very much intact and that the speed of light in a vacuum is always ~300,000,000 m/s, but that it can be much slower depending on what medium it passes through.

The same thing here - the speed of light in an optical fiber is definitely not ~300,000,000m/s in an optical fiber, but it is still very fast (about 2/3rds the speed of light in a vacuum). The rare-earth mineral they were using, erbium, is used in long-haul fiber to amplify the light pulses traveling through it. An erbium-doped fiber section (called an EFDA) is a spliced into the main cable every 100km or so and will amplify the light going through it. The erbium atoms are excited to an elevated energy level by another light frequency passing through it, typically 1480nm. The other communications light frequencies passing through the cable, either at 1310 or 1550nm, will be amplified by the erbium atoms as they release their energy as a photon of either 1310nm or 1550nm light (whichever is passing through). The process is not perfect and an EDFA will add a small amount of noise to the signal, but this reduces the requirements for powered regenerative repeaters along a long-haul optical fiber cable.

[LegendKiller]

:stupid:

What he said

[Houdini]

This does not surprise me at all. I work in the optical communications field, and I have had to deal with optical oddities quite a bit. I remember seeing someone who was not so smart write a letter at Maximum PC about how he was impressed that the mag had reported how IBM researchers had slowed down the speed of light to a virtual crawl (for light anyway). The letter writer stated that he was always a little disbelieving that Einstein's theory of relativity and how the speed of light was an absolute and was happy to see Maximum PC reporting such important breakthroughs. Of course, the editorial staff had to correct him saying that Einstein's theory was very much intact and that the speed of light in a vacuum is always ~300,000,000 m/s, but that it can be much slower depending on what medium it passes through.

The same thing here - the speed of light in an optical fiber is definitely not ~300,000,000m/s in an optical fiber, but it is still very fast (about 2/3rds the speed of light in a vacuum). The rare-earth mineral they were using, erbium, is used in long-haul fiber to amplify the light pulses traveling through it. An erbium-doped fiber section (called an EFDA) is a spliced into the main cable every 100km or so and will amplify the light going through it. The erbium atoms are excited to an elevated energy level by another light frequency passing through it, typically 1480nm. The other communications light frequencies passing through the cable, either at 1310 or 1550nm, will be amplified by the erbium atoms as they release their energy as a photon of either 1310nm or 1550nm light (whichever is passing through). The process is not perfect and an EDFA will add a small amount of noise to the signal, but this reduces the requirements for powered regenerative repeaters along a long-haul optical fiber cable.


Gotcha. And it's true that Al's theory is still intact. However, the article implied that the light's peak ended up at the far end of the fiber before the peak even reached the erbium, right? I understand the photochem stuff, emitting photons, etc., actually very well, but reports like this always make me skeptical. Sure, you can SLOW DOWN light, depending on medium and relative speed of photon emission, but to make a pulse happen somewhere before it's truly sent seems kinda fishy. I have to think more about it.

Then again, there was that guy a few years ago who was transporting atoms from one place to another in a weird Star-Trek fashion. Destroy something and it must end up somewhere else, depending on where you direct the energy, etc. Like a precursor to a transporter. I was skeptical then, and I haven't heard any news on that front for years.

[redcolours]

nerds!!!!

now i feel like i belong somewhere! yay!

[InfiniteNothing]

That is correct H. See animation here: http://www.rochester.edu/news/show.php?id=2544