In one minute

Clovis de Matos and Martin Tajmar use the Proca form of electromagnetism and gravitoelectromagnetism to derive the magnetic and gravitomagnetic properties of a rotating superconductor. A superconductor expels magnetic fields and, when rotated, produces a magnetic field called the London moment. Both perfect diamagnetism and the London moment follow from the photon acquiring mass inside the superconductor. By analogy, their proposal to resolve the Cooper pair mass anomaly reported by Tate is explained by a graviton mass inside the superconductor different from its cosmological value. For niobium the required graviton mass is about 10^-55 kg, 14 orders of magnitude above the free-space limit, just as the photon mass is greatly raised inside a superconductor by the Higgs mechanism.

Gravitomagnetic London moment and the graviton mass inside a superconductor