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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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  • by cybercuzco ( 100904 ) on Monday June 09, 2003 @08:53AM (#6149084) Homepage Journal
    Yes, its a working force-field, unfortunately it uses a 15,000 degree plasma in the process. If you tried this in say a jail cell, you would fairly quickly cook the occupant. And if you could get around that, if the occupant touched the field, his finger would cease to exist. Not to mention that it can only be created when surrounded by a magnet, so star trek "shields" are still a long way off.
  • by tuluvas ( 679950 ) on Monday June 09, 2003 @08:56AM (#6149119)
    Can you guys think of any reason to use this? I sure cant! probably expensive too. Sorry if its answered in the artical , i just barely skimmed it.
  • by 26199 ( 577806 ) * on Monday June 09, 2003 @09:01AM (#6149176) Homepage


    But if it's blocking against atmospheric pressure (not quite sure on that one) then it's an impressive feat...

  • The article sucks. (Score:5, Insightful)

    by Mac Degger ( 576336 ) on Monday June 09, 2003 @09:01AM (#6149177) Journal
    I love the idea, and the science around it, but the article sucks! No pics, diagrams or any actual detail on the way the thing works. I'm sick of this kind of 'it works because of herbs!' reporting; it's way too simple for any inquiring mind and because of that it's non-informative.

    A shame, 'cause I'd be interested in the practical implementation of this valve system. And I want pretty movies and/or pictures, of course :)
  • by 1stflight ( 48795 ) on Monday June 09, 2003 @09:05AM (#6149207)
    Since this does a great job at separating air, and a vacuum, this has great applications in space.
    Think launch bays that really can be opened up to have a shuttle pass though, and leave the air inside the bay intact.
    Yes, this idea has a lot of promise.
  • by arvindn ( 542080 ) on Monday June 09, 2003 @09:13AM (#6149265) Homepage Journal
    the plasma reaches a temperature of 15,000 degrees Kelvin

    First, its degrees only when it is Fahrenheit or Centigrade, which are not absolute units. Second, its Kelvins, damn it! (at least when it is more than 1K). People have no problem with Joules, Newtons, Pascals etc which are all people's names, why is Kelvins so different??

    [I haven't done any physics after high school, so if I'm wrong correct me.]

  • 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.

    I want to say something about this, but the sentence makes my brain hurt, and not in a good way.

    So... converting temperatures to Kelvin makes them lower? It may be that I'm too far removed from my math and science classes, but... well, come to think of it, I never learned it that way.

    Sheesh, they didn't even say "in Kelvins." "Degrees Kelvin" indeed... amateurs...

  • by Idarubicin ( 579475 ) on Monday June 09, 2003 @09:44AM (#6149516) Journal
    It's a "plasma valve". Not a force...

    Erm. I dunno. For a lot of laypeople, a valve with no 'solid' parts fits the definition of a 'force field'.

    (Note: I am embarrassed to use the following example.) Take the brig on Star Trek: TNG era vessels. There is a ring of emitters surrounding the door opening. These emitters are presumably responsible for maintaining an impenetrable field in the doorway. That 'force field' seems to be at least loosely similar (in form and stated goals) to the 'plasma valve' described--it's just larger.

    Oh, and the plasma valve would take your finger off if you touched it. Oh well. This is real life that we're stuck with, after all.

  • Re:Plasma Rays (Score:4, Insightful)

    by Little Brother ( 122447 ) <kg4wwn@qsl.net> on Monday June 09, 2003 @10:01AM (#6149677) Journal
    Blasters possibly, I really have no opinion on that, but lightsabers are still a bit off. Lightsabres are cohesive, that is, if you move the handle, the blade moves as though it were completly solid. It is unaffected by, or at least overcomes, the inertial forces that would cause it to bend (think of swinging a rubber lightsaber). It is not clear that a force field would allow this to happen. (Although it is possible) The biger problem with lightsabers, is that they are completly powered at the base of the beam, while the "force fields" span a gap between two (or more) points. We have, at this time, no way to terminate the lightsaber blade.
  • Re:Hehehe what?? (Score:5, Insightful)

    by chainsaw1 ( 89967 ) on Monday June 09, 2003 @10:04AM (#6149695)
    Except this wall has a very small, negligable mass.

    Thus, you could also make a balloon with extra lifting capasity just by vacuuming out the inside of a field. It could also fly closer to space than any other balloon, since it has a vacuume(essentially 0 density).

    Or you could have containment for mass-sensitive matter (antimatter, etc.)

    How about a see-through wall with zero heat transfer by contact?

    How about a wall that cannot melt, because there is nothing there to melt? We may finally have something we can melt diamond/carbon in

    Sometimes you have to think outside the ridgid plasma cube
  • by Matrix272 ( 581458 ) on Monday June 09, 2003 @10:36AM (#6150067)
    Does the field still prohibit any natural force acting upon it to move through or damage it? If so, then it's effective a force field... and it would seem that it does, given that it can hold back air from a vacuum (which qualifies as a "force"). Nobody cares about the technical definition of the terms "force field" or "plasma field". They care about whether they could make a door that sound won't pass through (2 of these fields with a vacuum in the middle) but you could see through and walk through (given that 15000 degrees Kelvin wouldn't harm you... read the rest of the comments by people far more knowledgable than I in matters of physics).

    Here's my question: Does it have to be completely surrounded by some kind of magnetic/copper thingamabob (too lazy to look it up right now)? By "completely surrounded", I mean X, Y, and Z Axis? Or, is it only necessary to surround it on 2 dimensions, X and Y? If only 2 dimensions are necessary, then the applications for this are almost too numerous to mention. Sound-proof walls, doors, windows (that never open or shut... rather just turn off), Star Trekie type inventions, etc. Depending on how cheaply they can reproduce a field, we could be seeing these types of devices practically everywhere. Suddenly I don't think Star Trek is too far fetched...
  • by Smallphish ( 320591 ) on Monday June 09, 2003 @11:15AM (#6150529)
    You are absolutely correct. A very high temperature something does not necessarily have a lot of heat. The heat that is transferred by an object, or a volume of a fluid, depends on the amount of force that the particles in that substance will exert on particles that they come in contact with, and the amount of loss of energy to radiating photons. Even if we ignore ratiating heat transfer, I figured a field such that the previous poster was describing, covering the server room door with enough force to hold back one atmosphere of pressure (to say nothing of PHB's!) would be giving off a large amount of heat by it's very nature. The article describes the field acting by having a plasma confined within an electromagnetic field, with a high enough temperature that when errant air molecules come in contact with ions screaming along at 15,000 Kelvins, they're *smacked* back in the direction that they came from. this would impart a lot of force on the air molecule, speed it up and increase its temperature. Now, if you're pumping enough energy into this plasma to keep enough of these collisions going on all at once to hold back an atmosphere pressure of gas over an entire doorway (approx. 44,452.8 pounds of pressure) that would, in my armchair analysis, be enough to transfer a significant amount of heat into the room.

    But then again, maybe it would only impart as much as a door :-)

    No, that's bullshit because the door molecules are very low energy and the plasma ions are very high energy. More energy transfer = more entropy = more heat.

  • by NewbieProgrammerMan ( 558327 ) on Monday June 09, 2003 @01:07PM (#6151803)
    Depending on how cheaply they can reproduce a field, we could be seeing these types of devices practically everywhere. Suddenly I don't think Star Trek is too far fetched...

    Well, even though they didn't provide pictures, I imagine that the area in which the plasma actually resides is not very big. It may not be too difficult to produce a plasma curtain to block off a 1-2 cm^2 entry point into a particle accelerator, but I wager it would be very difficult to produce the same effect uniformly over a 1 m^2 door opening. I don't know much about plasma physics, but I have a suspicion that a big honkin' 1m^2 sheet of plasma isn't going to be magically stable.

    I think the Star Trek force fields are still a long, long way off, if they're even possible at all.
  • Re:What's next? (Score:3, Insightful)

    by Imperator ( 17614 ) <slashdot2@omersh ... 159.net minus pi> on Monday June 09, 2003 @01:11PM (#6151835)
    Who would have thought that the mass production of lasers would lead to... 12-year old boys giggling in a movie theater and pissing everyone else off?
  • Re:Plasma jargon (Score:3, Insightful)

    by Celandine ( 610250 ) on Monday June 09, 2003 @04:44PM (#6154320)
    Nothing to do with exhibiting characteristics of a liquid: the defining feature of a plasma is that it's hot enough to be substantially ionized (i.e. a significant fraction of the electrons are freed from their parent atoms).

"Never face facts; if you do, you'll never get up in the morning." -- Marlo Thomas