Gravitomagnetic London Moment?

Two papers (experiment: gr-qc/0603033, theory: gr-qc/0603032), an ESA press release, and blog posts (Uncertain Principles, Something Similar, and Illuminating Science) today are all about a recent experiment performed by Martin Tajmar (ARC Seibersdorf Research GmbH, Austria) and Clovis de Matos (ESA-HQ, Paris) which they claim shows a gravitomagnetic effect in a laboratory experiment. Not only do they claim that they observe a gravitomagnetic effect, but that the effect comes not from the standard general relativity mechanism, but instead from their own theory which has massive photons and massive graviphotons (which is what the authors call the carriers of the force which arises when one linearlizes gravity and obtains equations which resemble Maxwell equations, i.e. spin 1 instead of spin 2)! Color me skeptical.
The experiment is actually fairly straightforward. Just take a superconducting ring and spin it up. The authors then look for a gravitomagnetic field which can be measured by nearby accelerometers. Now the normal gravitomagnetic field strength measured in their experiment is about 30 orders of magnitude lower than what standard general relativity predicts. But when they run this experiment they indeed do find accelerations in their accelerometers for superconducting rings (and none for non-superconducting rings.) The authors then intepret this effect as confirming evidence of their theory which invokes “gravitophotonic” masses. If this is correct, then this is an astounding result: not only does it detect a gravitomagnetic field, but it also is a field which is not arising from standard general relativity. Wowzer.
Of course you can color me skeptical. As Chad Orzel points out, the signal they are talking about is only about 3 times as strong as their noise. Now when you look at one of their runs, i.e. figure 4 of gr-qc/0603033, the peaks look pretty good, no? Well figure 4b is a little strange: the gravitomagnetic effect appears to occur before the acceleration. Okay a bit strange, but a single run proves nothing, right? Okay, what about figure 5? Ignore the temperature dependence now, but would you have picked out the peaks that they picked out? Okay so these things make me a little uneasy. Okay, so well certainly they did a lot of runs and tried to get some statistics on the effect. Indeed, they did something like this. This is figure 6. And this is what makes the paper frustrating: “Many measurements were conducted over a period from June to November 2005 to show the reproducibility of the results. Fig. 6 summarizes nearly 200 peaks of in-ring and above-ring tangential accelerations measured by the sensor and angular acceleration applied to the superconductors as identified e.g. in Fig 4 with both electric and air motor.” Why is this frustrating? Well because I have no clue how they analyzed their runs and obtained the tangential accelerations. Were the peaks extacted by hand? (And what is the angular acceleration? Is it the average acceleration?) Argh, I can’t tell from the paper.
Well certainly this is a very interesting set of papers (the theory paper is pretty crazy: if I get a chance I’ll try to go through it in some detail and post on it.) I would personally love to know more about the experiment. I spent this afternoon pondering if I could think up a way in which they get the effect they do, but I’m certainly no expert on this stuff, and might be missing something totally obvious.
(Note also that there is another claim of interesting gravitational effects around superconductors made by Podkletnov. For a history of this “anti-gravity” effect see Wikipedia. Since the Podkletnov experiment is considered controversial, the authors of the above article make sure to point out that they are not observing the effect Podkletnov claimed.)

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9 Responses to Gravitomagnetic London Moment?

  1. wolfgang says:

    The ‘theory paper’ begins pretty weird.
    “We know that the photon must have a mass due to Heisenberg’s uncertainty principle..”. The they cite as reference a paper which has mostly zero to do with such a claim.
    I do not know what they measure, but their explanation is pretty much nonsense from what I can see.

  2. Rafael says:

    “I do not know what they measure, but their explanation is pretty much nonsense from what I can see.”
    Perhaps they are elite pranksters? 😉

  3. Harry Green says:

    I don’t know how much knowledge of physics you have, but please believe me that even a PERFECT knowledge of the presently “accepted” physics and mathematics is not BY FAR enough to help one become a real scientis.
    I’m sorry to notice that you do not seem to have an independent thinking. And yes, you’re right, you do miss something obvious: that all the “laws” dicovered in the past are just assumptions, and they are probably far from perfect. You seem to be too attached to your imagined “absoluteness” of these “laws”. Science is an imperfect attempt, it does show improvements but it is not an absolute. Therefore, stop considering that past formulations of physical laws by famous scientists – formulations on which your skepticism is based – are absolute. Probably they are not.

  4. Dave Bacon says:

    I’m sorry to notice that you do not seem to have an independent thinking.
    You have a nice day, too, Harry.

  5. 12345 says:

    I’ve been intrigued by this since I first heard about Tajmar’s article. It’s easy to dismiss claims like this out of hand, but these guys seem (to me at least) to have a little more credibility than people like Podkletnov. I’ve included abstracts from an earlier Tajmar paper along with the abstract from a 1990 paper by Tate. Combined, they give a brief overview of the line of reasoning that lead to the ESA Gravitomagnetic London Moment experiment.
    ************************************************
    Gravitomegnetic Fields in Rotating Superconductors to Solve Tate’s Cooper Pair Mass Anomaly (Tajmar and De Matos)
    Abstract. Superconductors have often been used to claim gravitational anomalies in the context of breakthrough propulsion. The experiments could not be reproduced by others up to now, and the theories were either shown to be wrong or are often based on difficult to prove assumptions. We will show that superconductors indeed could be used to produce non-classical gravitational fields, based on the established disagreement between theoretical prediction and measured Cooper-pair mass in Niobium. Tate et al failed to measure the Cooper-pair mass in Niobium as predicted by quantum theory. This has been discussed in the literature without any apparent solution. Based on the work from DeWitt to include gravitomagnetism in the canonical momentum of Cooper-pairs, the authors published a number of papers discussing a possibly involved gravitomagnetic field in rotating superconductors to solve Tate’s measured anomaly. Although one possibility to match Tate’s measurement, a number of reasons were developed by the authors over the last years to show that the gravitomagnetic field in a rotating quantum material must be different from its classical value and that Tate’s result is actually the first experimental sign for it. This paper reviews the latest theoretical approaches to solve the Tate Cooper-pair anomaly based on gravitomagnetic fields in rotating superconductors.
    ************************************************
    Determination of the Cooper-pair mass in Niobium (Tate)
    Abstract. We have measured the ratio of Planck’s constant h to the observable mass m’ of a Cooper pair in a superconductor, using a rotating superconducting ring. The flux through such a ring of area S is zero for a set of rotation frequencies evenly spaced by Δν and h/2Ï€m’=2SΔν. Our measurements of S and Δν enable us to quote a value of m’/2me for niobium of 1.000084 (21). This result disagrees with predictions from currently available theories.

  6. TallDave says:

    One quibble: according to the BBC article, the observed effect is actually much larger than relativity predicts, not smaller.

  7. Dave Bacon says:

    Ack my wording was horrible. Fixed to be coherent.

  8. Khan says:

    Gravitomagnetic London Movement is an effect which is not in accordance with General Theory of Relativity. Does not this experimentally prove that there is something fundamentally wrong with GR? I fail to understand why this does not occur to anybody.However I would refer readers to an article ‘Michelson-Morley Experiment-A misconceived & Misinterpreted Experiment’ which proves that space does contain luminiferous ether & the concept of space-time is fundamentally incorrect.

  9. Khan says:

    I forgot to state that the article has been submitted to Indian Journal of Science & Technology & the article will be shortly available on http://www.indjst.org.

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