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Ummm... What about it? Scientists have been slowing light in Bose-Einstein condensates for years...
We had this discussion about speed of light a while back. It seems a1k0n was right after all ...
(AP) -- Physicists say they have brought light to a complete halt for a fraction of a second and then sent it on its way, an achievement that could someday help scientists develop powerful new computers.
The research differs from work published in 2001 that was hailed at the time as having brought light to standstill.
In that work, light pulses were technically "stored" briefly when individual particles of light, or photons, were taken up by atoms in a gas.
Harvard University researchers have now topped that feat by truly holding light and its energy in its tracks -- if only for a few hundred-thousandths of a second.
"We have succeeded in holding a light pulse still without taking all the energy away from it," said Mikhail D. Lukin, a Harvard physicist.
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.
The research may also have applications for improving conventional fiber-optic communications and data processing techniques that use light as an information carrier. Lukin said the present research is just another step toward efforts to control light, but said additional work is needed to determine if it can aid these applications.
The findings appear in Thursday's issue of the journal Nature.
Stanford University physicist Stephen Harris said the new research is promising and represents an important scientific first.
Matthew Bigelow, a scientist at the University of Rochester involved in light research, called the new study "very clever" and something that may ultimately spur the development of superior light-based computers.
"I think it's moving us in the right direction," he said.
(AP) -- Physicists say they have brought light to a complete halt for a fraction of a second and then sent it on its way, an achievement that could someday help scientists develop powerful new computers.
The research differs from work published in 2001 that was hailed at the time as having brought light to standstill.
In that work, light pulses were technically "stored" briefly when individual particles of light, or photons, were taken up by atoms in a gas.
Harvard University researchers have now topped that feat by truly holding light and its energy in its tracks -- if only for a few hundred-thousandths of a second.
"We have succeeded in holding a light pulse still without taking all the energy away from it," said Mikhail D. Lukin, a Harvard physicist.
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.
The research may also have applications for improving conventional fiber-optic communications and data processing techniques that use light as an information carrier. Lukin said the present research is just another step toward efforts to control light, but said additional work is needed to determine if it can aid these applications.
The findings appear in Thursday's issue of the journal Nature.
Stanford University physicist Stephen Harris said the new research is promising and represents an important scientific first.
Matthew Bigelow, a scientist at the University of Rochester involved in light research, called the new study "very clever" and something that may ultimately spur the development of superior light-based computers.
"I think it's moving us in the right direction," he said.
Since 1995. But light has been slowed down transparent / translucent liquids and solids since the beginning.
Yeah, that too... :P
Dude, it's like light...but slowed....woah.....
heh....
So if you got a burrito up to the speed of light... could you stop it before it destroyed a small village?
heh....
So if you got a burrito up to the speed of light... could you stop it before it destroyed a small village?
"So if you got a burrito up to the speed of light... could you stop it before it destroyed a small village?"
-A burrito up to the speed of light (3.00*10^8) would theoretically have infinite mass. If it had infinite mass it would technically pull the earth into its gravitational pull, along with the sun and everything else around it since infinite mass=infinite gravitational force. So it would destroy considerably more than a small village. And no, you wouldn't be able to stop it.
Of course, I could be wrong.
-A burrito up to the speed of light (3.00*10^8) would theoretically have infinite mass. If it had infinite mass it would technically pull the earth into its gravitational pull, along with the sun and everything else around it since infinite mass=infinite gravitational force. So it would destroy considerably more than a small village. And no, you wouldn't be able to stop it.
Of course, I could be wrong.
hem hem... you wouldn't even get a burrito to accelerate up to SOL. it just won't work. (and it's approximately 3*10^8 m*s^(-1), the m/s is important...)
and it's not about slowing down light (which is taking energy away from it, really), it's _stopping_ light, for however short a duration (without taking away the energy it carries).
there is a huge difference between slowing something down and stopping something. i just wonder how they knew it (light) stopped in its path, since you can't know the speed and the place of a particle at the same time (uncertainty principle). then again, as soon as it's stopped, you could measure it's dislocation compared to the previous location. err... problem is, that the earth moves relatively to the sun, and so forth.
would you mind producing the source of your newspost, andreas? of course i will look in the 'net for it, but i'd be happy if you could tell.
and it's not about slowing down light (which is taking energy away from it, really), it's _stopping_ light, for however short a duration (without taking away the energy it carries).
there is a huge difference between slowing something down and stopping something. i just wonder how they knew it (light) stopped in its path, since you can't know the speed and the place of a particle at the same time (uncertainty principle). then again, as soon as it's stopped, you could measure it's dislocation compared to the previous location. err... problem is, that the earth moves relatively to the sun, and so forth.
would you mind producing the source of your newspost, andreas? of course i will look in the 'net for it, but i'd be happy if you could tell.
toshiro: http://www.signonsandiego.com/news/science/20031209-2349-frozenlight.html
And they slowed down light too, to 38 mi/hr
And they slowed down light too, to 38 mi/hr
thankee, will read up.
It is actually possible to get a burrito up to the SOL, but it can't be just ANY burrito. It has to be from Taco Bell because their burritos are...
"fast food". sorry
"fast food". sorry
o.O Owww...
That's bad.
Sounds like something I'd come up with. Think I'll steal it.
*Paedric quickly checks to make sure no-one is looking, tucks the Taco Bell tag line under his leather jacket and casually walks out of the thread.*
*Paedric quickly checks to make sure no-one is looking, tucks the Taco Bell tag line under his leather jacket and casually walks out of the thread.*
Okay, so what's the speed of dark?
Dark is the lack of light, so a void of something can't really have speed. How many people say a pocket of nothing is moving?
It's not moving, it's propagating. wave-mechanics-like. So it's the same.
Dark is the lack of _visible_ light. But lets not try to get into this again ...
hm hm... by consequence, if dark means absence of light (i'll extend the envelope to "any" light), it must be exactly as fast as light. logical, innit?
i won't intrude upon the fact that absence of something is without physical manifestation (hence it can not have a "location", from which most things can be derived, such as speed, acceleration, force, work and power), because it'll soon get philosophical, and my head hurts.
i won't intrude upon the fact that absence of something is without physical manifestation (hence it can not have a "location", from which most things can be derived, such as speed, acceleration, force, work and power), because it'll soon get philosophical, and my head hurts.
I was being sarcastic about the Dark thing.
About three years ago, a woman in New Mexico at Los Alamos National Lab managed to use a series of mirrors and a very low temperature to slow the light particles down so that you could see it extend, it was estimated the light was slowed to about 45 Miles per Hour, but it's not exactly known becasue the experiment only worked twice and the first tim they weren't prepared for the test. The Liquid Nitrogen the lab used to lower the temperature of the mirrors to a fraction of a degree also caused them to shatter easily and several broke and the test wasn't conducted again, to my knowledge that is.
About three years ago, a woman in New Mexico at Los Alamos National Lab managed to use a series of mirrors and a very low temperature to slow the light particles down so that you could see it extend, it was estimated the light was slowed to about 45 Miles per Hour, but it's not exactly known becasue the experiment only worked twice and the first tim they weren't prepared for the test. The Liquid Nitrogen the lab used to lower the temperature of the mirrors to a fraction of a degree also caused them to shatter easily and several broke and the test wasn't conducted again, to my knowledge that is.
All transparent (to a specific electromagnetic wavelength) matter with a refractive index will 'slow' light to a degree. Your windows do it. Water does it. The atmosphere does it. In fact, if you have thick enough glass or polycarbonate over your screen you may well be lagging like hell in game.