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Light Slowed Down To 127 mph

Makarand writes "Although slowing down a light beam is as simple as passing it through a window pane, slowing down light dramatically has always involved extremely low temperatures and rooms full of complex equipment. A new small device developed at the University of Rochester can now slow light down to 127 mph without using the room-filling mechanisms previously required. The new technique uses a laser beam to create a hole in the absorption spectrum of a common ruby at room temperatures that can allow a second laser beam, with a frequency slightly different than the first laser, to shine through that hole at a greatly reduced speed. This light slowing device might find applications in the telecommunications industry."

12 of 53 comments (clear)

  1. Why not... by C0LDFusion · · Score: 3, Funny

    ...work on getting us to light speed, rather than getting light to our speed?

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    Only in slashdot are posts of solidarity modded at -1 Redundant, while posts of antagonism are modded as -1 Flamebait.
    1. Re:Why not... by jargonCCNA · · Score: 2, Funny

      But this is so much easier! Besides, it's kind of useful for proving that time is relative. Think about it. If a 'second' is the amount of time it takes light to travel x distance (the value of x here escapes me), and light now travels at 127 mph, then I guess a second is rather variable, now isn't it?

      --
      Matthew G P Coe
      http://mgpcoe.blogspot.com/
  2. On Another Note by Tolchz · · Score: 3, Informative

    Light travels even slower at 38mph
    http://slashdot.org/articles/99/02/18/0832249_F.sh tml

    1. Re:On Another Note by rtaylor · · Score: 2, Insightful

      Yes, but thats not exactly at room temperature is it?

      --
      Rod Taylor
  3. hmmm by the_other_one · · Score: 2, Funny

    Perhaps this could slow down fiber optic communications enough for a server to survive the /. effect.

    --
    134340: I am not a number. I am a free planet!
  4. Is it just me, by Mordant · · Score: 3, Funny

    or does it seem like these folks are sort of headed in the wrong direction with this stuff?

    "Scotty, we need 38mph now, or we're all dead!"

    Just doesn't have the same ring to it, you know?

  5. Arrgh! by TheSHAD0W · · Score: 2, Funny

    We finally get the government to raise the speed limits on highways, so what do they do? Put a speed limit on light! Arrgh!

    You just can't win.

  6. Moo by Chacham · · Score: 4, Funny

    The best part is, that we all know that when traveling faster than the speed of light in a vacuum, you can go backwards in time. So, by traveling slower than light in a vacuum, you move *forward* in time. As if this very moment I am traveling forward!

    If you'd like to try this, get an airtight container and step inside. Remove all the air (such as with a match). Then start moving slowly. When you get out of the jar you sill notice that it is *later* then when you got in!

  7. In related news by jrivar59 · · Score: 2, Funny

    Time was increased by 34 minutes an hour to enable posting april 1 articles on march 31.

  8. Non-believers by Sprunkys · · Score: 5, Informative
    Not many people seem to believe this. I don't really see why not as this has already been done long ago by Ad Lagendijk and others (please note, the original research was done at Amsterdam, not the University of Twente).

    Furtermore, Bigelow e.a published their paper in the Physical Review Letters on March the 21st, not on the first of April. They submitted their paper on 31 October 2002.

    From what I could make up of it, Ad Lagendijk did this in the early nineties by having the light reflect off of particles and thus slowing it down effectively (it doesn't emerge on the other side of the container at t=x/c where t is the time, x is the width of the container and c is the speed of light).
    Bigelow, Lepeshkin and Boyd really just created a ruby crystal with an enormously high refractive index, effectively slowing down the light. Nothing really odd.

    Concerning the application of this research in telecommunications the article mentions the following:

    Boyd anticipates that the slow light device will find a role in the telecommunications industry. When two signals from fiber optic lines merge, the two signals may reach the merging router at the exact same moment and need to be separated slightly in time so they can be laid down one after another. Like two cars merging on a highway where one may need to slow down to let another car into the lane, a light-slowing device could help ease congestion on fiber optic lines and simplify the process of merging signals on busy networks.


    This I know nothing about, however, this does seem a bit odd to me as I don't know how they intend to figure out where the light is in order to know how much to slow it down.
    --
    "We live in our minds, and existance is the attempt to bring that life into physical reality" Ayn Rand
  9. One step closer to Mallet Temporal Ethernet Card by A55M0NKEY · · Score: 3, Funny
    Now that slow light is easy, we should be seeing the Mallet Temporal Ethernet Card in WAL*MART any day now!!

    It consists of a vacuum tube surrounded by two helical rubys wrapped around in opposite directions. The momentum of the slow light traveling through the rubies warps spacetime in this device between the anode and the cathode of the tube. The electron beam is aimed so as to take a path through the warped spacetime region that will lead from cathode to the anode at a previous time.

    Using this nifty device ( ONLY $19.95! on sale now at Best Buy! ) you can surf the web of the future easily! Just set the date you want to surf in your control panel and open a url.

    How does it work? Your computer will save the http request on disc and send it out on the date you set in the control panel. On that date, it will recieve a reply and send the result back to your present self by encoding it as a cathode ray signal and sending it through the temporally warped region of the vacuum tube. The signal will travel from the cathode in the future to the anode of now.

    Worried that your brand new outdated software will be incompatible with the future Internet? Will http be phased out? Not to worry!! You can download compatible software from the future using this device! To your computer the Mallet Temporal Network Card looks like any other ethernet card. It can even be used to surf the present by setting today's date in the control panel so you don't need to worry about finding slots for two network cards.

    That's right, for just $19.95 you can download movies that haven't even been made yet! You can read tomorrow's obituaries and avoid a nasty car accident, you can play the Lottery and win - EVERY TIME! You can play the stock market without risk of losing your hard earned cash. Read books and download software that hasn't been written yet, and OWN THE COPYRIGHT! The possibilities are endless.

    Mallet Temporal Network Card - How did you ever live without one?

    --

    Eat at Joe's.

  10. Primary use of this technology by Tikiman · · Score: 4, Funny

    This technology will finally enable us to create "gun-style" laser weapons that can be ducked, dodged, and deflected with light sabres.