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Can Superconductors Block Gravitational Fields?

jswitte writes "Raymond Chiao, of the University of California at Berkel, believes that superconductors can convert electromagnetic radiation into gravitational radiation. His full paper can be found here. His theory is based on the idea that superconductors might be able to block the so-called 'gravitomagnetic' field just as they block the electomagnetic field in the famous Meissner effect allowing superconductors to levitate in magnetic fields. He claims that when he 'adds the gravitomagnetic field to the standard quantum equations for superconductivity, he confirms not only the gravitational Meissner-like effect but also a coupling between the two breeds of magnetic field. An ordinary magnetic field sets electrons in motion near the surface of a superconductor. Those electrons carry mass, and so their motion generates a gravitomagnetic field.'"

12 of 476 comments (clear)

  1. Sorry, no anti-grav by sequence_man · · Score: 3, Informative

    All he is exccluding are gravity-waves. These are different then the basic curvature of space that generates gravity itself. Basically they are little ripples that float on top of the curvature. So blocking them won't levitate us.

    1. Re:Sorry, no anti-grav by beanyk · · Score: 4, Informative
      All he is exccluding are gravity-waves. These are different then the basic curvature of space that generates gravity itself.


      If you mean "gravitational waves", then no, they are *not* different from the curvature of space. It's exactly the same stuff, though gravitational waves passing close to the Earth are probably very weak.So yes, they look like ripples on our pretty flat curvature, but they're just smaller-scale, generally weak curvature perturbations on a much more uniform background curvature.

      As an aside, the term "gravity wave" is usually taken to mean "wave formed by a process where gravity is significant", like some types of water wave. Not actually what's been talked about here.
  2. This has been around. by Max+Threshold · · Score: 3, Informative

    Isn't this just a new take on the Podkletnov effect?

    1. Re:This has been around. by Vireo · · Score: 4, Informative
      Isn't this just a new take on the Podkletnov effect?

      Excerpt of the article in the paper version of SciAm:

      (...) Even if Chiao's contraption works, it wouldn't allow the generation of antigravity fields, as Russian materials scientist Eugene Podkletnov, then at Tampere University of Technology in Finland, controversially claimed to have observed in 1992. (...)


  3. Re:Mmm... Time machine by sconeu · · Score: 5, Informative

    No doubt that the symmetry between Maxwell's equations and Einstein's equations is stark, but does this also mean that they are equivalent in meaning and applicability?

    If superstring theory is correct, then they've been known to be equivalent since the 1920s. The Kaluza-Klein equations show that in a 5-dimensional space-time (4xspace + 1xtime) or higher, Einstein's equations and Maxwell's equations both come out. See Kaku's Hyperspace for more info.

    --
    General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  4. Re:Why don't superconductors weigh less? by dragons_flight · · Score: 5, Informative

    Ordinary gravitational attraction is dominated by "gravito-electric" force, or in normal language the force generated by stationary masses. In everyday concerns the Earth is the only mass that matters and it is stationary to a good approximation for nearly everything humans do.

    The paper talks solely in terms of affecting "gravito-magnetic" forces, which are those exhibited by moving masses (and generally only significant among masses moving at an appreciable fraction of the speed of light). Simply put there just isn't enough gravito-magnetic force in every day life to notice any change. If there were an appreciable gravito-magnetic force in ordinary everyday gravity then yes you could test it, though I'm not clear how to expect it to react.

    To put things another way, Newton described gravity purely in gravito-electric terms and most of us will never notice the more complex gravitiational interactions that Einstein discovered and this physicist cares about.

  5. Re:Why don't superconductors weigh less? by PatientZero · · Score: 3, Informative
    It's been a long time since I did this (1988), but in my senior year of high school a couple friends and I made a superconductor with our physics teacher. With it we successfully reproduced magnetic levitation via the Meissner Effect: "If a small magnet is brought near a superconductor, it will be repelled becaused induced supercurrents will produce mirror images of each pole. If a small permanent magnet is placed above a superconductor, it can be levitated by this repulsive force."

    Thus, the superconductor is not affecting the gravitational field. It is in a sense becoming a magnet itself, producing an exact-opposite magnetic field. This new field simply repels the magnet, producing levitation. By far the coolest effect was spinning/flipping the magnet over the superconductor and having it remain levitated, as the superconductor's magnetic field was always a mirror of the magnet's.

    Now, in this I am not talking about the article or paper (I just started reading it). I'm simply talking about the magnetic field that is induced in a superconductor by magnets. My only experience and knowledge of the subject was the experiment in high school.

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  6. Remember Eugene Podkletnov? by Byteme · · Score: 5, Informative
    ...and his anti-gravity machine? This looks somewhat similar...

    Dr. Podkletnov was discounted as a hoax by many sources (cited that rising gases from the coolant, air flow from spinning or magnetism influenced his results), his university ejected him and now he has retreated to a hermetic existence.

    Here is a story on Wired for your reading pleasure.

    Much more to look if you search Google.

  7. Sidebar says no anti-grav by Wraithlyn · · Score: 5, Informative
    If you click the sidebar link at the bottom, there is a paragraph that reads:

    "Even if Chiao's contraption works, it wouldn't allow the generation of antigravity fields, as Russian materials scientist Eugene Podkletnov, then at Tampere University of Technology in Finland, controversially claimed to have observed in 1992 (see link ). Antigravity requires canceling out a powerful, static gravitoelectric field, yet superconductors have no effect on such fields."
    --
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  8. Re:I had a friend once . . . by SilverSun · · Score: 3, Informative


    He did get a measurable increase, but it was too little to be more than measurement error.


    Do you realize that your statement does not make any sense? If he got not more than a measurement error could acount for, then he did not get a measurable increase.

    --

    KdenLive/PIAVE - non-linear video editing

  9. Re:I'll believe it when I see it. by p3d0 · · Score: 3, Informative

    Carl Sagan's original quote was that "extraordinary claims require extraordinary evidence".

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    I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
  10. Re:I'll believe it when I see it. by aallan · · Score: 5, Informative

    ...the method described is science in action, the way it is supposed to work.

    No, actually this isn't how things work these days. Science has become so specialised that there are very, very, few people that can do both theoretically and experiemental work at the cutting edge.

    Most of us have a fairly good knowledge of a very small corner of one field, a slightly less good knowledge of the entire field, and an educated layman's knowledge of the rest of our discipline. Outside of our own discipline our knowledge is fairly scanty, most physicist's knowledge of chemisty for instance is probably no better than your average layman.

    It's just not possible to keep up with everything even in your own field anymore.

    The characteristic of bogus (or "junk") science is theories that give predictions that are untestable, or theories that predict things that have already been proved experimentally to be untrue.

    While I haven't read the paper, not alot of point as I'm not a quatumn physicist, and my knowledge of quatumn field theory is fairly basic, this guy seems to have made predictions which are provable. This is good science. Whether he is right or wrong is imaterial (to the scientific process), his theory is interesting enough that some experimentalist will pick this up and run with and then we'll find out whether the theory is correct (or not).

    Just because he hasn't provided extrordinary proof, doesn't mean that he's doing bad science.

    Al.
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