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Gravitomagnetic Analog of Electrical Transformers

  1. Jul 6, 2010 #1
    Based on Maxwell's equations, a physicist suggests that there should be a way to have a transformer to step-up or step-down gravity:

    http://www.technologyreview.com/blog/arxiv/25407/

    What could such a gravitomagnetic transformer look like in nature?
     
  2. jcsd
  3. Jul 6, 2010 #2
    You'd have to create many loops of the conducting medium. In electric circuits it would be a conducting wire, with gravity, you'd have to create many "loops" of spacetime, which I don't think is possible.
     
  4. Jul 6, 2010 #3

    marcus

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    Here is the original article by John Swain:
    http://arxiv.org/abs/1006.5754
    Gravitatomagnetic Analogs of Electric Transformers
    John Swain
    (Submitted on 30 Jun 2010)
    "Linearized general relativity admits a formulation in terms of gravitoelectric and gravitomagnetic fields that closely parallels the description of the electromagnetic field by Maxwell's equations. For steady mass currents, this formalism has been used to understand gravitomagnetic effects like the Lense-Thirring dragging of inertial frames. For time-varying mass-energy currents, the analog of Faraday's law suggests new effects based on the gravitational equivalent of a transformer where such currents take the place of electrical currents. New experimental possibilities are suggested including a novel coupling mechanism of electromagnetism to gravity, new tests of general relativity in the ultrarelativistic limit using particle beams in the LHC, and searches for a materials exhibiting the gravitational analog of ferromagnetism."

    Friend said something about "many loops in spacetime" but I don't think that is what Swain is talking about. Here he seems to be talking about bunches of particles circulating in a particle ring like the Tevatron or the LHC.

    As I recall, Swain is an experimental high energy particle physicist, primarily. If I remember right, he has been associated with some HEP group either at Geneva or at some university in the Usa midwest. He knows the particle accelerator business, sending particles around and around in rings. He occasionally writes theory papers about gravity etc, but that is not his main specialty. I think he is developing an idea here which has some practical experimental consequences involving HEP technology, even though it sounds very far fetched.

    I don't think it has any practical consequences. It would be more like testing General Relativity in a novel way----like they did with that Gravity Probe B satellite that detected "frame-dragging". Interesting but very delicate effects, just barely detectable.

    I could be wrong, just had a minute or two to read it. That's my take.

    Here, I checked his webpage:
    http://www.physics.neu.edu/swain.html [Broken]
    He describes himself as "an experimental high energy physicist with a strong interest in related theory".
    That's how I remembered him.
     
    Last edited by a moderator: May 4, 2017
  5. Jul 6, 2010 #4

    Ben Niehoff

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    No, you don't need loops of spacetime. You just need pipes to carry mass-current. You'll need a very dense fluid moving at near-light speeds to see any noticeable effect. So, think huge coils of pipes filled with mercury, flowing near the speed of light...and even then you might not see much of anything. If you could fill your pipes with liquid neutron star core material, then you'd have better luck. If it works, then a current in one coil should induce a current in the other coil, inversely proportional to the winding ratio.

    However, Nature already provides us with gravitational transformers: rotating black holes! (Or other very dense rotating objects, like neutron stars). The rotation of the dense object induces mass current in the surrounding accretion disk, causing it to rotate as well. The two coils of this transformer happen to be concentric (which is the most efficient configuration if you do not have a core material of high permeability).
     
  6. Jul 6, 2010 #5
    A fundamental difference between electricity and gravity is that conduction electrons are available for electrical power generation in appropriate materials while gravitons are billions and billions of times more scarce and not easily obtainable. gravity is pervasive but weak on small scales by comparison.


    Kip Thorne discusses some related aspects in BLACK HOLES AND TIME WARPS but does not go quite so far. His discussion around page 407 discusses a spinning curvature of spacetime outside a black hole horizon (referred to by Marcus quote as "...dragging of inertial frames.." causing the magnetized field lines to spin which creates an accelerated plasma.... and voltage and current (power).

    In any case, the most concentrated gravitational power we have (in theory) so far are black holes....but they appear rather unwieldly so far.
     
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