Question of the nonlocality of the Aharonov-Casher effect

The Aharanov-Casher effect is manifested in a (2+1)-dimensional model that screens the electromagnetic fields, in order to demonstrate that the effect is essentially nonlocal in its nature. The question of nonlocality is discussed by means of a nonrelativistic model for a superconductor. It is demonstrated that although the superconductor screens the electric field generated by an external charge it does not screen the modular electric field which is a constant of motion of the system. Consequently, a magnetic fluxon will accumulate the same phase as if the electric field were unscreened and the Aharonov-Casher effect will exist even in a force-free region.