[QUOTE][QUOTE][IMG]http://www.popsci.com/files/imagecache/article_image_large/articles/mixing.png[/IMG][/QUOTE]
Our nation’s official keepers of time and other standards are breaking one of the cardinal rules: They have
figured out how to make superluminal light pulses. This paradoxical sentence —[URL="http://www.nist.gov/pml/div684/light-050212.cfm"]faster-than-light light[/URL] — is
from a new paper explaining how to make the sine wave of light hunch in on itself and arrive a few nanoseconds
earlier than it would if it had moved at light speed.
Nothing can move faster than light, as neutrinos [URL="http://www.popsci.com/science/article/2012-02/bummer-faster-light-neutrinos-werent-and-it-was-cable-guys-fault"]coldly reminded us[/URL] earlier this year. Einstein’s constant C, for
the speed of light in a vacuum, is a universal constant. But researchers at the National Institute of Standards
and Technology are playing some tricks with physics.
A short burst of light can be expressed as a curvy wave, with the hump representing the peak of the burst. The
whole wave cannot exceed the speed of light, but apparently you can do some physical manipulation to that hump
and make it arrive earlier or later than it’s supposed to. Ryan T. Glasser, Ulrich Vogl, and Paul D. Lett at NIST and
the Joint Quantum Institute manipulated the hump using a technique called four-wave mixing. It re-arranges the
light waves that comprise the pulse of light and makes the hump move forward.
The researchers pulsed ultra-short (200 nanosecond) laser pulses into a cloud of rubidium vapor, [URL="http://www.nist.gov/pml/div684/light-050212.cfm"]according to NIST[/URL].
Next to this seed pulse, they pumped in a second laser beam at a different frequency. The rubidium amplified the
seed light, so its hump hunched forward. While this was happening, photons — because light is a wave[I]and[/I] a particle
— interacted with the vapor and formed a second pulse, which could also be tuned to travel faster or slower than
it is supposed to. The peaks of these light waves arrived at their targets 50 nanoseconds earlier than they would
have if they were traveling at the constant C.
Aside from proving that it’s possible to bend the rules, the NIST team could use this breakthrough to study some
strange quantum effects of this fast light, which could be useful in quantum information processing.
[QUOTE][tab]Source: [/tab] [URL="http://www.popsci.com/science/article/2012-05/fed-sluggish-neutrinos-scientists-force-light-move-faster-its-own-speed-limit"][B]PopSci[/B][/URL][/QUOTE][/QUOTE]
[QUOTE=Jo The Shmo;35827975]I don't understand enough physics to really grasp what's happening here
how much of a big deal is this? and how true is it?[/QUOTE]
I shall read it a bit and come back.
[QUOTE=Jabalab;35827987]So they made light... faster?[/QUOTE]
They made a certain point in the wave arrive slightly earlier in the wave, the wave still travels at the same speed.
I was expecting light that was traveling at 1.5c, not 50 nanoseconds faster.
Besides, the last faster-than-light claim turned out to be a fuckin loose cable at CERN.
Professor Farnsworth was right
I think the basic principle is that they're doing something similar to athletes racing, they put their chest further out just as they get to the finish line to put themselves ahead.
Is this basically the same thing?
I think the article is a bit misleading. What they meant is, that the hump is travelling faster than it should, but still below light-speed.
Some of you might not know it, but light speed isn't equal to light speed, as light propagates slower if it's in a medium like air. This is due to the light getting refracted by the atoms of the air (or in this case Rubidium gas), so it doesn't propagate in a straight line anymore, and thus appears to be a bit slower than light in vacuum.
So they probably found a way to make light propagate faster than the light speed you'd expect in the specific medium rubidium, but this isn't breaking the light speed in vacuum.
The possible application for this could be in optical fibers, as light only propagates at around 80% of the vacuum light speed within those, so maybe this new research can lead it to being raised to 85%, resulting in a smaller ping when playing on servers across the ocean.
[QUOTE=Dr.C;35828052]Professor Farnsworth was right[/QUOTE]
He said 2208
Lying cunt
[QUOTE=DrLuke;35828061]I think the article is a bit misleading. What they meant is, that the hump is travelling faster than it should, but still below light-speed.
Some of you might not know it, but light speed isn't equal to light speed, as light propagates slower if it's in a medium like air. This is due to the light getting refracted by the atoms of the air (or in this case Rubidium gas), so it doesn't propagate in a straight line anymore, and thus appears to be a bit slower than light in vacuum.
So they probably found a way to make light propagate faster than the light speed you'd expect in the specific medium rubidium, but this isn't breaking the light speed in vacuum.
The possible application for this could be in optical fibers, as light only propagates at around 80% of the vacuum light speed within those, so maybe this new research can lead it to being raised to 85%, resulting in a smaller ping when playing on servers across the ocean.[/QUOTE]
I don't know about you guys, but that still sounds pretty awesome.
[QUOTE=Used Car Salesman;35828046]I was expecting light that was traveling at 1.5c, not 50 nanoseconds faster.
Besides, the last faster-than-light claim turned out to be a fuckin loose cable at CERN.[/QUOTE]
Nanoseconds is not a measure of speed. If it's a certain distance, 50 nanoseconds faster can mean 0.5c. Also, this has nothing to do with CERN.
"Faster-Than-Light Light"
You know what, fuck you, science.
Is it true that if we ever made a car that went precisely the speed of light, then turned on the head lights; would that technically catapult the light to go even faster than light?
[QUOTE=Secrios;35828180]Is it true that if we ever made a car that went precisely the speed of light, then turned on the head lights; would that technically catapult the light to go even faster than light?[/QUOTE]
No, that's not how light works.
Dammit, came in here to make the Futurama reference.
[QUOTE=Secrios;35828180]Is it true that if we ever made a car that went precisely the speed of light, then turned on the head lights; would that technically catapult the light to go even faster than light?[/QUOTE]
No, and this is explained by relativity. It's simpler to explain at close-to-light speeds, since things get a bit weird when you go at the speed of light (infinite mass, relative time freezes etc.). If you're familiar with relativity, you'll know that the closer you get to the speed of light, the faster time passes for you. This acceleration of time will counteract the decreased speed of c compared to you. Speed is measured by how far something moves in a certain time unit, for example one kilometer per hour. When you go faster, the distance light has traveled from someone else's perspective relative to you will be shorter, but since what you perceive as one second is more than one second from an observer standing still, light would have moved the same distance in the same time unit for you. I'm trying to explain some fairly odd and complex physics here, and if someone think they can explain it better, feel free to do so.
[QUOTE=Secrios;35828180]Is it true that if we ever made a car that went precisely the speed of light, then turned on the head lights; would that technically catapult the light to go even faster than light?[/QUOTE]
No, you'd perceive the light as still moving away at lightspeed.
Also travelling at exactly lightspeed is wacky, as space shrinks with increasing speed. At lightspeed, space shrinks to zero, so any distance you'd want to travel would have the length of 0, but so would you. This is another proof that light speed can't be reached, as you'd create a division by zero problem when moving through space.
Another interpretation could be, that you suddenly appear to be everywhere in the universe at once, as any distance is 0 and you can instantly travel to it.
basically light is a dickhead with self esteem issues
This isn't new to be honest. Similar things were done already since the 1980s. The injected pulses and generated pulses travels with a negative group velocity.
From Wikipedia about Group Velocity.
[QUOTE]Since the 1980s, various experiments have verified that it is possible for the group velocity of laser light pulses sent through specially prepared materials to significantly exceed the speed of light in vacuum. However, superluminal communication is not possible in this case, since the signal velocity remains less than the speed of light. It is also possible to reduce the group velocity to zero, stopping the pulse, or have negative group velocity, making the pulse appear to propagate backwards. However, in all these cases, photons continue to propagate at the expected speed of light in the medium.[/QUOTE]
[URL="http://jqi.umd.edu/news/312-first-fast-and-faster.html"]Ahem.[/URL]
[h2]NIST scientists emphasized that, while the information detection could be advanced, no information could actually travel faster than the speed of light and that, consequently, principles like causality in special relativity were always respected in these experiments.[/h2]
Never. Trust. Popular. Science.
[QUOTE=Swebonny;35828354]This isn't new to be honest. Similar things were done already since the 1980s. The injected pulses and generated pulses travels with a negative group velocity.[/QUOTE]
Yeah, this is just a newer method of an old process that has less distortion issues.
But that doesn't sound as cool as HOLY SHIT LIGHT GOING FASTER THAN LIGHT SO AWESOME SCIENCE!!!!1!!1!
more like warp 1.000000005
[QUOTE=soulharvester;35828041]They made a certain point in the wave arrive slightly earlier in the wave, the wave still travels at the same speed.[/QUOTE]
About damn time, I want my neighbor to see my laser pointer all that much quicker!
[QUOTE=DrLuke;35828061]I think the article is a bit misleading. What they meant is, that the hump is travelling faster than it should, but still below light-speed.
Some of you might not know it, but light speed isn't equal to light speed, as light propagates slower if it's in a medium like air. This is due to the light getting refracted by the atoms of the air (or in this case Rubidium gas), so it doesn't propagate in a straight line anymore, and thus appears to be a bit slower than light in vacuum.
So they probably found a way to make light propagate faster than the light speed you'd expect in the specific medium rubidium, but this isn't breaking the light speed in vacuum.
The possible application for this could be in optical fibers, as light only propagates at around 80% of the vacuum light speed within those, so maybe this new research can lead it to being raised to 85%, resulting in a smaller ping when playing on servers across the ocean.[/QUOTE]
As relevant as ever:
[IMG]http://i47.tinypic.com/1zbh00k.gif[/IMG]
[QUOTE=Swebonny;35828354]This isn't new to be honest. Similar things were done already since the 1980s. The injected pulses and generated pulses travels with a negative group velocity.
From Wikipedia about Group Velocity.[/QUOTE]
Similar things have been observed in space before, too: [url]http://phys.org/news182671620.html[/url]
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