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Near light-speed space travel?

  1. May 13, 2008 #1
    All right, so here it is!
    Archer Enterprise states that they have a theoretical device (in process of proof of concept) that can reach speeds near that of light. Looking at the description of the theory of the device, it looks like this could work, at least in electrically propelling space vehicles without using conventional fuel (it uses electrons as fuel). This device, i think, doesn't break any
    physics laws known.

    Before anyone has a nervous breakdown:rofl:, before you visit the links I would like to clarify what certain terms mean. When the say reactionless, they do not mean that it breaks the law of momentum or conservation of energy. Here is the really basic ideal of how it works
    First, you have your classic ufo flying saucer shape that is symetrical in the x and y axis. If you don't know what I'm talking about, go google it! (or look on website). Anyways, the edge of the saucer is charged to a very negative voltage while the two hulls at the top are charge to a very positive voltage (all done by electrostatic induction). This causes electrons to stream from the negative to the positive side. These electron's arcs are influenced by a dynamic electric and magnetic field (see diagram on website). The electrons are accelerated to near the speed of light and are impacted onto the bottom and top hull, producing a large thrust one each hull. The current flow can be made different between the top and bottom hull (changing resistance), thus a net force can be produced in whatever direction.

    I encourage you to calculate the force, using relativity kinetic energy, that an electron with, say, 30 MeV (reasonable?) of energy can produce and then find out the total force produced in 10+amps of current. Or, better yet, calculate the energy that the electron will 'receive' as it accelerates from negative to positive side (lol, you'd need a lot more info, including hull shape, resistance, etc. which is in patent if interested, i think)

    Anyways, here's links

    (about halfway down, right after they talk about book!, it explains in general the device)


    Patent with full description (39 pages of small text!):
    So, what's your feedback?
  2. jcsd
  3. May 13, 2008 #2
    Sorry about that patent link. for some silly odd reason when i paste it it gives an error. Since i can't post a link (not 15 posts yet), you'll just have to go here
    and click on US6404089 (B1) pdf file

    EDIT: Um, that's a little weird, espacenet is now down for maintenance?
    Last edited: May 13, 2008
  4. May 13, 2008 #3
    Simply, electrostatic induction is used to amplify voltage to high levels. Look at a van-de-graff. What does it require? a simple motor, plus some other stuff. A small sized (OK, small relative to a person) could produce 100 kV. This apparently uses electrostatics isimilarly to produces large voltages.
    Oh, and by the way I just picked 30 mEv off the top of my head because I remember in my physics book that this was what electrons using a van-de-graff generator in the original particle accelerators could produce.
  5. May 13, 2008 #4
    Um, did a post get deleted? I could have sworn there was a second post that wasn't mine, saying something about how it was 'ridiculous?'
  6. May 13, 2008 #5


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    They may not claim as much, but for their engine to work as advertised it would have to break the laws of physics. Essentially they are saying that can accelerate the electrons up to near light speed and then essentially absorb their energy in collision. IOW, they make use of Newton's Third Law in extracting momentum from the electrons but ignore it when it comes to giving it to them in the first place.

    It's pure flim flam.
  7. May 13, 2008 #6
    Umm.... Explain better? I don't see how this violates any laws. All its doing is converting electrical and magnetic energy to kinetic energy and then transferring the resultant energy to the hull? In addition, did you consider that the magnets are 'permanent' magnets and that in order to propel the electrons (which are exerted on by magnet), one doesn't have to add energy to the magnets?. Permanent magnets last quite a while
  8. May 13, 2008 #7


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    "For every action there is an equal an opposite reaction". When you accelerate the electron's in one direction, there is an equal force that pushes back on the magnets. This will completely cancel out any momentum gotten by impacting the electron against the hull. Result, no net motion. There is no way around this.
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