The Meissner effect puzzle and the quantum force in superconductor

The puzzle of the acceleration of the mobile charge carriers and the ions in the superconductor in direction opposite to the electromagnetic force revealed formerly in the Meissner effect is considered in the case of the transition of a narrow ring from normal to superconducting state. It is elucidated that the azimuthal quantum force was deduced eleven years ago from the experimental evidence of this acceleration but it can not solve this puzzle. This quantum force explains other paradoxical phenomena connected with reiterated switching of the ring between normal and superconducting states.