Slashdot Mirror
Slow Light = Fast Computing
yohaas writes "The Washington Post is reporting that scientists have been able to slow the speed of light while still maintaining its ability to transmit information. The researchers have even developed a way to 'tune' the process, modulating how fast or slow the light goes within controlled circumstances. From the article: 'Scientists said yesterday that they had achieved a long-sought goal of slowing waves of light to a relatively leisurely pace and using those harnessed pulses to store an image. Physicists said the new approach to taming light could hasten the arrival of a futuristic era in which computers and other devices will process information on optical beams instead of with electricity, which for all its spark is still cumbersome compared with light.'"
We don't say "slow light" anymore. We say "Luminescentally Challenged".
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
...in terms of how small their underclock of c is.
Ok, they had me up to here. There's no way a single photon makes a stencil image.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Friends don't let friends enable ecmascript.
worst pun ever
Well...ok, but...
Howell and his colleagues created a four-inch-long chamber filled with cesium gas heated to about 212 degrees Fahrenheit.
I'm guessing that this isn't going to be coming to the desktop anytime soon.... even a major datacenter might balk at the energy costs of doing this versus a parallel traditional solution.
Oh. I was hoping that once you have read the article that you'd be able to tell us that.
We are already worried about data center power usage. I'm pretty sure it costs a bit to have cesium gas hanging around the data center.
Support NYCountryLawyer RIAA vs People
using light to store an image is called reflection. We've been doing it for years.
Slow glass
UC Santa Cruz have achieved a 1/1000 slowdown of light by passing a beam through a cloud of marijuana smoke.
worst pun ever Boy, that sounded like a challenge.
Light, for all its flare, can't hold a candle to electricity's current ability to generate a buzz around computing!
Worst pun ever? Pfha! We have not yet begun to pun!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Is that the stencil is actually a fourier transform hologram, printed out on film. This would look like a pattern of seemingly random dots, but a focused beam of light would resolve the hologram image, even if sent photon by photon over time on a detector.
We already have a household appliance that can reach much higher temperatures than that. Just hook your computer up to your kitchen stove and you're good to go!
Eviscerati.Org: All Hail the Eviscerati
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
Actually this is an opportunity to enable fast-than-light travel... instead of speeding up the ship, slow-down c. If we can slow it down enough, I could race light and win!
Views expressed do not necessarily reflect those of the author.
Didn't IBM do this a long time ago? http://science.slashdot.org/article.pl?sid=05/11/0 3/1544233&tid=136&tid=126&tid=14
So Cesium slows things down....
Yet, this artcle which was reported on Slashot here, says
I'm a bit confused. Does Cesium speed thing up or slow things down?
Have you read my journal today?
Now we have an explanation for all the Sci-Fi movies where the beam from some "ray gun" is visible (let alone moving at a perceptible speed)! I can enjoy the genre again as this technology provides a way for me to overcome cognitive dissonance!
I paid the going retail price for a Windows screen reader and got a free Unix computer!
"No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it."
a pun at all.
The Kruger Dunning explains most post on
Also, to save power, make a spaceship that stays still and moves the entire universe around it!
"When the atomic bomb goes off there's devastation...but when the atomic bong goes off there's celebraaaaation!"
Three guesses what that image was...
Yeah - winning a race through a 4" long cesium filled chamber is impressive. Woohoo! Once you've got your cesium tube to Alpha Proxima built, I'll be impressed. Until then ... meh.
Aww damnit.. I would have had first post if it weren't for this crappy light traveling at normal speeds...
Comment removed based on user account deletion
Interesting. This is essentially the photon version of AC then. Now, correct me if I'm wrong but:
1. Change in electric potential means that signals propogate at the speed of light across a chip.
2. Change in speed of photon would require photon that carried signal (or rather, the "breakpoint" where the speed changed) to travel across a chip.
Anyone else think that the first actually propogates information *faster* than the second? Now granted, photons are a lot easier to deal with (I've plugged in fiber cables backwards, nothing blows up), but the sensing (receiver) device would need to be fairly complicated.
Here is a half decade old article that describes the process well. It also uses units such as nm and Kelvin instead of thigs like "seven times around the earth" and "about 450 degrees below zero"
f reeze/lightfreeze.html
http://www.physics.hku.hk/~tboyce/sf/topics/light
don't cut it off www.mgmbill.org
but nobody would ever see you win!
The Kruger Dunning explains most post on
These types of articles are misleading. The speed of light in a vacuum is c or 299,792,458 m/s. This obviously cannot change. How the slowing of light does occur is not by slowing the photon, but by the electrons interfering with the electromagnetic radiation that is light. This gives the illusion of "slower" light.
Obligatory Wikipedia article to back me up.
Funny createSig(Witty remark, Odd reference)
{
return (Funny)remark + (Funny)reference;
}
Rest assured we will. :)
Is the light really being slowed down here, or are the photons just taking the scenic route to their destination instead of going in a straight line?
Could this be used to make a window to look out of that would show me what happened five minutes ago?
"Not an actor, but he plays one on TV."
It's been done already. Light slows down whenever it passes through anything. It only manages to get up to 299 792 458 ms-1 in a perfect vacuum. Even air slows it a little bit.
Whenever a beam of light moves from one medium, eg. air, to another, eg. glass, its speed changes. If it enters on the skew, so the speed of one side of the beam changes before the other side, then the beam changes direction; just like a vehicle with a binding brake, it swings towards the side that slows down first. When it comes out of the glass back into air, it speeds up again and changes direction again, exactly the reverse way to what would have happened on the way in (since a beam of light always follows the same path, whichever end it's shining from); unless it's travelling at such an angle there's no way it could ever have got to be travelling in that direction by going through the surface and slowing down a bit sooner on one side than the other. In which case it simply bounces off like a pool ball hitting the cushion and tries to escape somewhere else. This is how fibre optics work.
It also means that when you blast a pulse of light into one end of a long fibre optic, some of it comes straight along the middle and out of the other end at the speed of light in whatever stuff the fibre is made out of; but some of it takes a longer journey, bouncing off the walls, and some of it bounces more times than others. So you get a longer pulse at the far end than you originally put in (and dimmer, since the same amount of energy is now being spread over more time). If you're sending many pulses at a high enough frequency, there comes a point when the first pulse hasn't finished arriving at the far end before the second pulse goes in, and the receiver won't be able to tell which is which. Also, if the fibre goes through a bend, sometimes some light that you thought was going to bounce off the walls actually strikes at such an angle as it can get out. With modern, highly flexible materials, this can actually happen without you bending the fibre enough to break it.
If you want maximum bandwidth out of your fibre, you have to take these phenomena into account. You can buy cheap acrylic fibre, with LEDs and phototransistors that screw-couple onto it; these can often be used for RS232 links with no additional components, using the transmitter to light the LED and the phototransistor to pull down the voltage at the receiver, but you'll be lucky to get more than 9600 baud through such a link. With just some simple signal conditioning, you can make it run much faster.
Je fume. Tu fumes. Nous fûmes!
Just line the chamber with Pentiums.
Weaselmancer
rediculous.
lighting up the PC.
...their computer will never be as fast as Hex.
+++Out of Cheese Error+++ +++Please Reboot Universe+++ +++Redo from Start+++
Find environmentally and socially responsible products on http://buy-right.net
Every office keeps a coffeepot this hot all day long and no one complains about cost or heat dispersal.
Of course, you could just run it on a very hot cup of tea*.
*'Hitchhiker's Guide to the Galaxy' reference.
Serving your airship needs since 1995.
...I have to slowly dim the lighting of my room ?!?
Truly you are the Great Pundit of puns, and I did pretend pun in jest, I guess.
Unaccountable leaders are masters, and unrepresented people are slaves. How do US and EU fare?
If electricity is so cumbersome, why isn't light already being used in our microprocessors?
The speed of light in a vacuum is c or 299,792,458 m/s. This obviously cannot change. [...] How the slowing of light does occur is not by slowing the photon, but by the electrons interfering with the electromagnetic radiation that is light. This gives the illusion of "slower" light.
The view that the speed of light in vacuum is any more fundamental than the speed of light in materials is pretty simplistic. After all, we already know that the speed of light in vacuum is not exactly constant.
It's not a single photon interfering with itself. It's interfering with all of the photons that came before it and will come after it.
Now if they can realign the EPS conduits to work with this burgeoning ODN.
Fiat Homos et Pereat Theos
Does this mean we could take, say, one second worth of light coming into a camera and then slow it down so that we could get a picture at a super high shutter speed at any point during that one second period?
Slashdot: Failed Car Analogies. Amateur Lawyering. Anecdote Battles.
Cesium is the strongest non-radioactive alkali metal. Cesium is also dense enough to sink in water. BOOM!
Braniac on YouTube
"What's the use of a good quotation if you can't change it?" - Doctor Who
When will somebody figure out how to speed up light such that going for a nice dinner at that quaint little cafe overlooking the crystalline fields on that lovely planet around Tau Ceti is feasible?
If you can slow light down, does that mean that if we can slow it to about the speed of a person walking, we'll all gain infinite mass and be incapable of moving any faster?
Think of the children!
Screw the rules, I have green hair!
That is it did up until they tried to observe the photon, at which point it started acting like a particle.
Why would an unobserved photon act like a wave (producing the pattern) while an observed photon acts like a particle (no pattern)?
I'm using slow light processors to post this message. I posted it 2 days in the future, but it only arrived right now.
With slow light it is always the group velocity that counts, so far anyway. What is really exciting is that phase is preserved. Think of how mind bending this is. Applications in interferometry are a very exciting prospect.
----
Discosure: This is a bit of self-promotion here.