Electro- and Magnetostatics of a Cosmic Pseudoscalar Field Coupled to Electromagnetism

A spatially-inhomogeneous, time-varying cosmic pseudoscalar field coupled to electromagnetism via the Chern-Simons invariant acts as a new source of charge and current for electromagnetic fields. We evaluate the magnetic field produced by a static electric charge, and the electric field resulting from a stationary current. We show that the pseudoscalar exerts a torque on objects carrying both electric charge and a magnetic moment.