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Fastest Waves Ever Photographed

starfoot writes, "Pictures of the fastest waves ever photographed, traveling at 99.997% of the speed of light, were presented today at the APS Division of Plasma Physics meeting in Philadelphia. The waves were formed in the wake of an intense laser pulse passing through a plasma of electrons and ionized atoms. The waves create enormous electric fields (over 100 billion electron volts/meter), which can be used to rapidly accelerate charged particles to high energies in the span of a few meters. The pictures will help scientists better understand wakefield interactions — an important factor in their quest to replace machines that accelerate particles over the course of miles with compact, tabletop versions. High energy particle accelerators are vital for cutting edge physics and many types of medical therapy, and miniaturizing them would be a boon for both basic physics research and medicine."

8 of 167 comments (clear)

  1. Yeah right by UbuntuDupe · · Score: 3, Funny

    I bet it was just photoshopped. Gimme ten minutes, and I can give you a wave doing 99.999% of the speed of light.

  2. Ok, seriously... by Lord+Aurora · · Score: 4, Interesting
    Wouldn't the fastest waves ever photographed be...you know...light waves? And don't we photograph those every day? Correct me if I'm wrong, but light goes 100% the speed of light.


    Dead serious, I know there's a difference here between my family photo album and the pretty graph thing FTFA, could someone explain to me why photographing LIGHT doesn't count here?

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    The heavens do not fall for such a trifle.
  3. Re:Request for Clarification by wass · · Score: 3, Interesting
    Particle physics has nothing to do with it, it's just straight old electrodynamics (E&M). Your assumption is correct, they specically say it's the electric field, and the slashdot blurb incorrectly inserts the word 'electron' there.


    The electric field is merely the negative gradient of the scalar potential (ie, voltage)*. So in SI it will have units of Volts/Meter.


    * (Just in case any E&M sticklers want to point that my electric field definition here ignores the contribution from vector potential, just assume a time-independent gauge).

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    make world, not war

  4. Fast, but how fast? by abscissa · · Score: 3, Funny

    If you made instant coffee in the microwave, would you go back in time?

  5. How easy is it? by Gracenotes · · Score: 3, Interesting
    100 billion electron volts/meter sounds like a lot. In reality, if the same amount of physical energy were applied to a paper clip over one second, it would be moved 8.0108823 microns. That's 0.000315389067 inches; 0.00080108823 centimeters. Completely not impressive.

    The reason this is so awesome is that scientists can apply this to nanotechnology -- actually, the prefix "nano" is not small enough. After all, everything moves in waves, but these waves are only noticeable on a small enough scale. On this scale, electric energy is so much more important than gravity. The fact that this energy is electric and not physical means that, instead of bumping atoms around continuous for a month, something might happen sooner. The fact that it's been proven done might help with something, like (for example) supplying a power source. The question is, "How easy is it to synthesize this phenomenon, and is it worth it?"

    What excites me most is the fact that
    a technology that could make tabletop high-energy particle accelerators a reality.
    Are we still afraid of put explosives into our chemistry kits for fear that kids might get hurt? Just like how, around Sputnik time, the US gov't tried to make all of the children in its public education system little scientists of future, it is (seriously) important to get kids interested in science, math, and academic pursuit at a young age. Can a little kid read the KJ version of the Bible at 4 years old, as was done in days of yore?

    It would be a good thing that, with this increased technology, scientists would try to give nuclear chemistry to the public and make atomic physics more tangible. There was an ambitious project some time ago that wanted to create a huge electromagnetic field somewhere in Texas. It was shut down because the US gov't saw no use of it. If this technology can do something as simple as power a light bulb, the public will notice. No one cares if Element 118 is created in a matter of seconds instead of across the span of a week, but if people can actually see something, this is better for science in general. (So long as John Galt doesn't get angry.)
  6. Medical Applications? by dch24 · · Score: 3, Interesting

    many types of medical therapy

    Hey, so I understand the applications in Physics of desktop particle accelerators, but what kinds of medical therapy use particle accelerators? Wikipedia suggests creating rare "proton-heavy" isotopes, but I'm having trouble finding more about what kinds of "killer apps" (pun intended) would be enabled if there were cheap desktop particle accelerators. Someone in med school?

  7. Re:Fine Print... by Oink · · Score: 3, Interesting

    These laser pulses are on order 100 femtoseconds. That's 100 * 10^-15 seconds. That works out to only about 3 Watts assuming the 30 TW and 1 shot per second (which is reasonable).

    This is nothing compared to the petawatt laser that is being built in the same building here at UT in the same building that this published research was done (one door down from my office in fact). They can only take a shot every 45 minutes after charging a huge bank of capacitors.

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  8. Re:Five 9s by all204 · · Score: 3, Informative

    Here is a neat little proof of this: http://en.wikipedia.org/wiki/.999