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Possibility of a lightsaber

  1. Apr 1, 2004 #1
    okay, how many Star Wars nerds do we have here?

    i'm thinking about the possibility of a lightsaber. given there are several major hurtles that we'd need to get through but i'm just trying to sort this out.
    a) i've realized it could not be a 'light' saber. the photons could not spontaniously stop. a plasma saber is what i've decided on. problems with plasma saber:
    *******needs LOTS of power in small area. could only be 'activated' 2-3 times before depletion. possible solution: once activated plasma could be stored in magnetic bottle until ejection. (note: this uses power to maintain but is less than heating a gas to a plasma temperature everytime)

    *******needs a way to control extreme heat (possible solution to the latter: use an extremely low grade plasmas...like 1000-2000 degrees F

    b) it would have to be emitted in a fountain-like path. emitted from the inside and somehow pulled back in by magnetic coils. (remember this is an ionized gas so it would be easy to control its movements.)

    feedback? ideas? constructive critisism?
  2. jcsd
  3. Apr 1, 2004 #2


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    Seems to be best done via CGI or as available from FAO Schwartz. :)

    For the magnetics though, use super-conductors. As I understand it, once the material drops below super-conducting temperature, it retains (and doesn't lose or gain) any magnetic strength until it is heated up to past its SC point. Maybe someone can elaborate more, I'm out of my depth at that...

  4. May 20, 2004 #3
    Negative criticism: once the plasma exits the shaft to hold it, you need to stabilize it. If you figure out to do that, you would probably find the Holy Grail to making nuclear fusion possible. I think that magnetic fields inside plasma are pretty much inherently unstable.
  5. May 27, 2004 #4


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    The problem is that these Critical temperatures are really low...(often colder than -150C or -240F). You need to have your superconductors under liquid nitrogen to make them work. This is not happening.
  6. Jul 1, 2004 #5
    Hey all,

    Was just thinking about out-of phase electomagnetic radiation from the shaft of the sabre being able to form a "wall" for high-energy-potential volume within which a mild plasma could be housed, maybe temporarily. However, the conditions under which it would remain plasma, etc would be specific. Have to read up more on Magneto Hydro Dynamics of plasmas (MHD / Plasma Physics)

    Btw this could have other uses - we may be able to transport energy cleverly from nuclear reactors without leaking any particles but for light. So radiation shields would suffice in that case.

    Of course, the point is to try and find out how to become that clever! :wink:
  7. Jul 21, 2004 #6


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    hmm, as merely an effect, and not a weapon, couldn't you have some kinda solar sail typa thingy hooked on say a 3 ft cord (wire). The wire is mounted in the handle of the saber, which also houses a super bright light, which when active focuses on the sail, forcing it out to the end of the wire, and then reflecting off the sail, back into the handle, blah blah.

    Like I say, you couldn't slice Obi Wan in half with it, but you could probably have the best flash light in town.
  8. Jul 21, 2004 #7
    Now why would you want to do that? Don't be tempted by the Dark Side!
  9. Jul 22, 2004 #8


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    hehe, while I'm thinking about it, check this out:
    http://atomfilms.shockwave.com/af/content/atom_1403 [Broken]

    Anyhow, I believe something similar to my idea would work. Nasa (I think) had a thing that would spin and fly upward at a pretty fast rate, using nothing but a laser on the ground aimed at the craft.

    If the craft was small enough, attached to a cord that would keep it from going to the moon, and the light could be seen, maybe even by using LEDs of whatever color you could get the visual effect of a light saber.

    Doing it with plasma sounds kinda like asking to blow oneself up.
    Last edited by a moderator: May 1, 2017
  10. Jul 29, 2004 #9
    megashawn: Was the craft a mirrored cone? :rolleyes:

    I saw something like that on discovery, where they used a laser pointed into the cone. The mirror reflects the beams to a focal point which heats up the air, and then you hear a freaking loud "pop" :surprise: and the cone takes off into the air continuosly "popping" until the wind blows the cone away from the beam.

    I'm not sure if this is the same thing that you were talking about?
  11. Aug 11, 2004 #10
    Stick a LED on the blade of regular sabre.
  12. Aug 12, 2004 #11
    The craft your thinking about is called (pretty obvious) the lightcraft.
    The laser superheats the air underneath the cone.

    Looks hella cool anyway.
  13. May 7, 2008 #12
    Infrared Light sword

    Instead of using a dangerous and high-energy material like plasma, I think it may be possible to make and infrared light sword using easier and cheaper materials. First of all, some infrared laser frequencies produces photons that can cut through substances, so all you would need would be and infrared laser emiter with a crystalized mirror at the top help up by a magnetic force. The mirror would bounce back the laser and hit another one-way mirror at the bottom two produce a "collumn" of deadly light!:cool:
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