Search for Frame-Dragging-Like Signals Close to Spinning Superconductors
M. Tajmar · F. Plesescu · B. Seifert · R. Schnitzer · I. Vasiljevich
Summary and citation · read the original at the source · arXiv assumed licence for legacy submissions (1991-2003 terms applied to this record)
Na jednej stronie
This is the follow-on to the Seibersdorf group's 2006 gravitomagnetic London moment paper, and it is the round where the group turns its own instruments on its own result. Martin Tajmar and colleagues spin rings of niobium, aluminium and YBCO inside a liquid helium cryostat, with accelerometers and fibre-optic laser gyroscopes held in an evacuated steel chamber that is mechanically decoupled from every moving part. The signals do not go away. But three things about them do not fit the original hypothesis. The temperature at which the effect appears is not the material's superconducting transition. Aluminium, which is not superconducting at these temperatures, shows it too. And the laser gyroscopes see it strongly in the clockwise direction only, which is a parity violation no superconducting model predicts. The authors set their own numbers against the Canterbury ring laser and against Gravity Probe B, and report what that comparison does to the theories, including their own.
Dlaczego ma tu znaczenieChapter 11 needs one example of a research group testing its own strong claim harder than its critics would, and this is it. The same table that reports a signal rules out every published model of amplified frame-dragging around superconductors by up to four orders of magnitude, and the authors' own Cooper-pair mass hypothesis by five. That is the evidence ladder of chapter 1 being climbed by the claimant.
Co twierdzi
01The apparatus is built so that a mechanical explanation has to travel a long way to reach the sensors. Rings of niobium, aluminium and YBCO about a hundred and fifty millimetres across are spun by a brushless servo or a pneumatic air motor inside a liquid helium cryostat bedded in one and a half tonnes of sand, while the accelerometers and gyroscopes sit in an evacuated stainless steel chamber that acts as a Faraday cage and is tied by three solid shafts to the building floor and ceiling, with at least five millimetres of clearance to anything that turns.Section, Experimental Setup, with Figures 1 and 2
What to watch02With the niobium ring near liquid helium temperature and the vibration offsets removed by alternating the direction of rotation, a signal remains above the noise. The ratio of measured acceleration to applied angular acceleration is minus 2.26 plus or minus 0.3 times ten to the minus eight in the superconducting range, against minus 1.24 plus or minus 1 times ten to the minus nine when the same ring is normal conducting, with a correlation of 0.78 between the measured and the applied acceleration for the first peak.Section, Accelerometer Measurements, with Figure 4
What to watch03Three features of the gyroscope data do not match a superconductivity-driven effect. The critical temperature at which the signal appears does not coincide with the material's superconducting transition; aluminium rings show the effect as well as niobium and YBCO; and the effect is greatly pronounced in the clockwise direction only, which is a parity violation.Abstract; Section, Laser Gyroscope Setup; Summary and Conclusion
What to watch04Set side by side with an independent test, the numbers scale together rather than by material. Table 1 gives coupling factors for the Seibersdorf rings of 5.3, 3.2 and 3.8 times ten to the minus eight for YBCO, niobium and aluminium, against 37.7 plus or minus 13.2 for the Canterbury Ring Laser Group's silica measurement and an upper limit below 0.1 from Gravity Probe B, an enhancement over classical frame-dragging of about ten to the eighteen throughout. The authors read that as a field behaving like a classical frame-dragging field, greatly amplified, rather than like a superconducting phenomenon.Summary and Conclusion, Table 1
What to watch05The same comparison is turned on the theories, including the authors' own. Table 2 sets the predicted coupling factors of three published models against the experimental limits, and the Gravity Probe B data rules all of them out by up to four orders of magnitude, while the experimental data rules out the group's original Cooper-pair mass anomaly hypothesis of 2003 and 2005 by five orders of magnitude.Summary and Conclusion, Table 2
What to watch06What would settle it is named in the paper. The gyroscope and accelerometer channels disagree by a factor of a hundred under the standard induction law, and the authors say plainly that it is not yet clear whether a systematic such as vibration rectification is responsible or whether the mismatch is real, a possibility that had itself been predicted theoretically. Every laser gyroscope systematic modelled so far sits at least three orders of magnitude below the measurement, and further testing for residual vibration offsets is the stated next step.Summary and Conclusion, closing paragraphs on the gyro-accelerometer mismatch and on systematic effects
What to watch
Droga do źródła
https://arxiv.org/abs/0707.3806Posted to arXiv on 25 July 2007 by the Space Propulsion and Advanced Concepts group at the Austrian Research Centers in Seibersdorf, and presented in the STAIF conference proceedings. The arXiv record carries no Creative Commons licence, so this page reproduces no text of the paper and sends the reader to the free full text at the link above. SOURCE FOR THE CLAIMS. The preprint was fetched from arXiv and read in full on 2026-09-11; every summary sentence, claim and locator below is written from it, with locators naming the paper's own section headings and numbered tables.
Jak cytować
M. Tajmar, F. Plesescu, B. Seifert, R. Schnitzer, I. Vasiljevich (2007) Search for Frame-Dragging-Like Signals Close to Spinning Superconductors. arXiv:0707.3806
Gdzie leży w programie