Manipulating light and matter

[Susano]

Lene Hau has already shaken scientists’ beliefs about the nature of
things. Albert Einstein and just about every other physicist insisted
that light travels 186,000 miles a second in free space, and that it
can’t be speeded-up or slowed down. But in 1998, Hau, for the first
time in history, slowed light to 38 miles an hour, about the speed of
rush-hour traffic.

Two years later, she brought light to a complete halt in a cloud of
ultracold atoms. Next, she restarted the stalled light without changing
any of its characteristics, and sent it on its way. . . .

Now Mallinckrodt Professor of Physics and of Applied Physics, Hau has
done it again. She and her team made a light pulse disappear from one
cold cloud then retrieved it from another cloud nearby. In the process,
light was converted into matter then back into light. For the first
time in history, this gives science a way to control light with matter
and vice versa. — Harvard Press release/Staff photo Justin Ide/Harvard News Office

http://farm1.static.flickr.com/178/384246090_ac2d537aa8.jpg?v=0

Article:
http://www.news.harvard.edu/gazette/2007/02.08/99-hau.html

Video:
http://www.hno.harvard.edu/multimedia/flash/vid_hau2007.swf

[Nolgroth]

I really wish I understood the science behind that, because that is way cool.

[Mister E]

http://en.wikipedia.org/wiki/Bose-Einstein_condensate

I ran across Bose–Einstein condensate a few years ago when I was doing some random quantum physics googling. It's so cold that it is considered to be a new state of matter, where practically all movement is zero. I know jack about physics, but I guess according to the Heisenberg uncertainty principle (http://en.wikipedia.org/wiki/Uncertainty_principle), (where the more certain you are of the velocity of a particle, the less certain you are of its position, and vice versa), the fact that there is so little movement (and thus you pretty much know how fast its moving... nearly zero) means the substance effectively fuzzes out in space... causing atoms to meld into each other and form a 'super-atom' with unexpected physical properties... such as slowing down (and I guess stopping) the speed of light (which is/was considered to be a constant).

[Starwolf]

That proves a couple of things Light can be further manipulated (for who knows what effects), and light/energy is a form of matter and as such can be handed appropriately. I read an article a few years agoo where a light pulse was somehow accelerated and "supposedly" (meaning I don't understand how) was measured to have actually regressed in time by an infitesimal fraction of a second.

[TheRavenIs]

You know this means that eventually we can get past the so-called Ultimate Speed Limit.

[ajackson]

No it doesn't. The ability to slow down light proves nothing; we've known about this phenomenon for more than a century (it's why a lens works).

As for 'accelerating' light, the version I'm aware of was a bit of a cheat. Basically, if you treat light as a wave, you can measure speed based on the front of the wave, the back of the wave, or the peak of the wave. The normal measurement is based on the peak. It is possible to chop off the tail of a light wave so that, while the _front_ of the wave moves at light speed, the _peak_ of the wave seems to be slightly ftl -- because you've chopped off enough of the back and middle so the peak is at a different point in the wave.

[Mister E]

You know this means that eventually we can get past the so-called Ultimate Speed Limit.

Yeah, I wonder.

[BobGreenwade]

You know this means that eventually we can get past the so-called Ultimate Speed Limit.Probably. Not necessarily, since a number of factors can go into each phenomena (slowing light, and traveling faster than the classic limit), but probably.

[Jaxom]

Keep in mind that by definition we talk about the speed of light in a vacuum. A Bose Condensate is quite definitely *not* a vacuum. That's not saying that the physics is not cool... Just keeping in mind that there is nothing here that says c is not still a constant.

The idea of transferring data via light and then analog is not different either. This is more about the properties of Bose Condensates than anything about light. You all know how to use light to encode data into a physical medium and then use light to recover the data and if you don't you should go buy a CD burner (because that is exactly what it does).

[Thia Halmades]

Why hasn't Cancer or Nyrath chimed in on this? I'm curious to hear their thoughts.

[Nyrath]

Well, I sort of doubt this work will result in FTL travel, but it is majorly cool none the less. Lene Hau is a scientist to watch.

I'm sure it will find some application in optical computers that will make the current crop of supercomputers look like electronic abacuses.

And it does lead to some interesting thought about application to the problem of teleportation.

As a plot seed, I'm sure if Lene Hau did get a lead on teleportation, every supervillain mastermind on the planet will immediately try to kidnap her...

[Cancer]

ajackson and Jaxom have said what I'd say ... they aren't messing with the speed of light in vacuum, which is the speed limit. They've got a case where the speed of light in a particular medium is very slow. That slowing isn't really news. It's some of the other aspects of the situation which are interesting.

There's cool stuff here, but it's not FTL tech. As Nyrath said, the possibilities of 3D data storage and manipulation are where this seems particularly interesting.