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Experimental Detection of the Gravitomagnetic London Moment

M. Tajmar·F. Plesescu·K. Marhold·C. J. de Matos
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Abstract

It is well known that a rotating superconductor produces a magnetic field proportional to its angular velocity. The authors conjectured earlier, that in addition to this so-called London moment, also a large gravitomagnetic field should appear to explain an apparent mass increase of Niobium Cooper-pairs. This phenomenon was indeed observed and induced acceleration fields outside the superconductor in the order of about 10^-4 g were found. The field appears to be directly proportional to the applied angular acceleration of the superconductor following our theoretical motivations. If confirmed, a gravitomagnetic field of measurable magnitude was produced for the first time in a laboratory environment. These results may open up a new experimental window on testing general relativity and its consequences using coherent matter.

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M. Tajmar, F. Plesescu, K. Marhold, C. J. de Matos. 2006-03-09. Experimental Detection of the Gravitomagnetic London Moment. https://arxiv.org/abs/gr-qc/0603033

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