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Science

Force Field. No, Really 434

tqft points out news of "a working force field, using plasma. Now to scale the sucker up." Here's the Brookhaven press release. I can think of so many uses for this.
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Force Field. No, Really

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  • Some cool benefits (Score:1, Interesting)

    by Iron Monkey543 ( 676232 ) on Monday June 09, 2003 @08:54AM (#6149096)
    COuld be used on spacecraft. Less weight!! (unless equipment used to produce the barrier is heavy)

    Clean decapitation. You lower a loop onto a person until it levels his neck. Turn on the plasma field, and it chops his head off? I wonder if this can be used to cut trees as well! Cut anything!
  • by zackbar ( 649913 ) on Monday June 09, 2003 @09:14AM (#6149270)
    Not really much pressure though.

    I think it's mostly blocking stray molecules of air that get in from leaks until the leaks can be patched.
  • by brunes69 ( 86786 ) <[slashdot] [at] [keirstead.org]> on Monday June 09, 2003 @09:14AM (#6149273)

    This thing is for use in sci-tech research only, for creating air tight vacums. It can't be used to protect / encase eevryday objects. For example, I quote:

    At 15,000 degrees Celsius (27,032 degrees Fahrenheit), the plasma valve is about 50 times hotter than room temperature when measured in degrees Kelvin. This intense heat makes the ionized atoms and molecules move around and collide with air molecules so rapidly that the ions block any air molecules that might pass through the plasma valve.

    In short, don't expect this force field to be in use at your neighborhood brig / jail anytime soon :) A really cool advancement though.

  • my stupid idea (Score:2, Interesting)

    by Graspee_Leemoor ( 302316 ) on Monday June 09, 2003 @09:26AM (#6149368) Homepage Journal
    If you could make a huge-scale forcefield that wouldn't repel matter but allow it to rest on it you could make ... TRANSPARENT AIRCRAFT!

    The military would probably be interested, but I'm more into the idea of see-through 747s- just think of the view!

    I suppose you'd still have to have most of the aircraft solid, unless force fields can act as wings etc for aerodynamic purposes (IANAP), but you'd still end up with the equivalent of glass-bottomed boats, except far cooler.

    graspee

  • SCI FI wonderland (Score:2, Interesting)

    by Darkseer ( 63318 ) on Monday June 09, 2003 @09:29AM (#6149395) Homepage
    Brookhaven National Labs is awsome man. I interned there one summer and forcefields are the least of their toys. The place is out in the middle of Long Island NY and looks almost totally harmless from the outside. Inside they have all the latest and greatest science tools, everything from nuclear reactors to partical accelators. 10 Years ago they figured out how to do 3D medical imaging like you see in science fiction movies and methods to do surgury with radiation beams. If your ever out that way sign up for the tour, its enlightening.
  • by KDan ( 90353 ) on Monday June 09, 2003 @09:31AM (#6149413) Homepage
    If you consider all those high-energy particles trapped in the earth's magnetic field, you can look at their speeds statistically and find out what their speed distribution is. From that, you could probably derive a measure like temperature (assuming they actually follow a Maxwell-Boltzmann distribution). However, I agree that that is a pretty useless way to look at things. Temperature is a man-made concept to make a lot of common place things (involving large numbers of particles in thermal equilibrium) easier to understand. It was never designed be applied to exotic things like high-energy particles trapped in magnetic fields. It can be applied to them nevertheless, but won't tell you much.

    Daniel
  • by EvilTwinSkippy ( 112490 ) <yoda AT etoyoc DOT com> on Monday June 09, 2003 @09:47AM (#6149547) Homepage Journal
    Did anyone else in the process of reading this think "Gee, this sounds just like Maxwell's Demon."

    Maxwell's Demon is a physics problem the is the basis of quantum mechanics. Simply, suppose you had a tank of air that was divided in 2 by a tiny split, with a gate. At the gate is a "demon" who lets high energy particle in on side, and low-energy particles in the other.

    Theoretically, by expending no energy save that to open and close the gate (plus whatever overhead the Demon requires) you could thwart the laws of physics. Soon one side of the tank would be "cold" and the other "hot" even if they both started off at the same temperature.

  • Umm, calc please! (Score:2, Interesting)

    by teeheehee ( 12647 ) * on Monday June 09, 2003 @09:51AM (#6149576) Homepage
    Correction:

    15,000 / 50 = 300

    50 is completely reasonable here...

    I'm not as sure about this, but I found a link in Google to something that looks reputable... some plasmas exist at temparatures as low as 1,500 degrees. According to this [san-bernardino.ca.us] [www.co.san-bernardino.ca.us] water turns to plasma at 1,500 degrees - but unspecified Kelvin, Celsius, or Fahrenheit. If it's Fahrenheit (a farely safe assumption that it's either F or K because it's US,) then 1,500 F = 1088.7055555556 Kelvin, so it's still within reason. If it's Celsius, then 1,500 C = 1773.15 Kelvins, still not so bad...
  • by SkArcher ( 676201 ) on Monday June 09, 2003 @10:11AM (#6149766) Journal
    Even if it is not yet blocking against atmospheric pressures, it is a design that one would hope to see some development work done on.

    If it can be used to block a 1 atmosphere pressure (or even above) it would solve a whole bucket load of problems.
  • by Open_The_Box ( 620252 ) on Monday June 09, 2003 @10:18AM (#6149824)
    If it's an enclosed plasma that can block anything then it's pretty darn impressive, lets be honest. ;) The atmospheric pressure thing will depend on the exact physical set up though. But having worked with vacuum equipment I'd estimate that with vacuum on one side and air leaking in on the other you're really talking about how much air is leaking into the gap. i.e.:

    leak in system plasma wall
    | |
    | enclosed |
    atmos area at | vacuum
    | atmos - x |
    | |

    Obviously with this set up the amount of air leaking in will increase with time (albeit possibly slowly) until x=atmospheric pressure. I certainly wouldn't want to trust my delicate equipment inside the vacumm to anything that wouldn't hold back the full pressure of the air outside.

    Of course I'm only guessing since there're no numbers or anything in the article but it is a great achievement anyway.

  • by Smidge204 ( 605297 ) on Monday June 09, 2003 @10:25AM (#6149923) Journal
    I think the best example of this would be the Hilsch Tube [visi.com].

    BLow air in the middle, hot air blows out one end and cold air blows out the other. Temperature difference can be as much as a few hundred degrees C depending on the configuration used! (Still doesn't violate any laws of thermodynamics though... but it does 'sort' high and low energy molecules without ant "extra" energy)
    =Smidge=
  • by Jack_Frost ( 28997 ) on Monday June 09, 2003 @11:25AM (#6150657)
    The body can stand immense positive pressure, but nasty things happen with very low pressures. The boiling points for things like water (which your flesh has in abundance) come way down. Check out the water phase diagram sometime. Interesting things happen at sufficiently low pressures, like room temperature boiling, sublimation, etc that are beyond the normal intuitive understanding of everyday materials.
  • by Bill Currie ( 487 ) on Monday June 09, 2003 @11:43AM (#6150868) Homepage
    The worst that happens to flesh exposed to vacuum is a modest amount of cell damage at the surfrace, and (possibly) the bends. I don't have a link, but I remember reading an article somewhere about a test pilot removing his glove while at some stupidly high altitude. All that happened was his hand got cold (it wasn't quite a vacuum), red and some minor cell damage on the surface layers. Skin does an admirable job of keeping the water in :)

    Heck, large quantities of youths get smallish (~1 square inch) regions of flesh exposed to near vacuum conditions all the time with nothing worse than a red welt to show for it.

  • Oooh! Oooh! Oooh! Integer values for x, y, z that satisfy x^27 + y^27 = z^27? Well I can think of several right off the top of my head...

    x=1
    y=-1
    z=0

    or

    x=0
    y=1
    z=1

    Or did you want a non-trivial answer for that?

    [FLAME ON]
    Now, in the words of Dennis Miller, "I don't mean to get off on a rant", but speaking as a Math/Comp Sci. geek, I hate it when people attempt to sound intelligent by frobbing their mighty mathematical muscles. Most people wouldn't know (or care) what the integral of e^(-x^2) is, nor for that matter what you define as "fundamental mathematic expressions" are either.

    That's basically like asking someone for a grenden frenesdhire of lignitious flibidnituriousness. Without the context or the intellectual framework to understand the question, it's meaningless. Do YOU have a grenden frenesdhire of lignitious flibidnituriousness? I thought not.

    As for your example with Andromeda, a pair of rubber bands and a liquid lunch...well, even you state that there is a vanishingly small chance of being solvable. Vanishingly small, but non-zero. Just because we currently do not know how to do it now doesn't mean we never will.

    Remember, at one point in time, many leading scientists believed it was impossible for man to fly, even AFTER Kitty Hawk. The Wright brothers were considered crackpots in their time. Next, it was the sound barrier. "Man will never break the sound barrier", they said. It's been broken. The history of scientific progress is littered with so-called experts saying "It can't be done." and the men who proved it could.
    [FLAME OFF]

    That being said, there ARE classes of problems which are considered unsolvable. Turing's Halting Problem [wikipedia.org] (Note the use of a link providing information for those interested in learning more and/or are not gifted with near-omniscient intellect) is one of them. Alan Turing proved that there is no algorithm which can solve it for any possible inputs. It's a mindbendingly elegant proof...you can see a sketch of it on the other side of the link if you're interested.

    Anyway, sorry for the flame. Your post caught me as being a little too intellectually smug and self-flagellating. Had to be done.
  • by Anonymous Coward on Monday June 09, 2003 @04:38PM (#6154258)
    I had found this to be an interesting read, but I would need to see it to beleive it. ...David Swenson of 3M Corporation describes an anomaly where workers encountered a strange "invisible wall" in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. ...

    rest of arcticle can be found here
    http://www.amasci.com/weird/unusual/e-wall.h tml

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