Nonlinear electrodynamic lag of electromagnetic signals in a magnetic dipole field

We investigate the propagation of electromagnetic waves in the magnetic dipole and gravitational fields of a neutron star, which follows the laws of nonlinear electrodynamics in a vacuum. Electromagnetic signals in these fields are shown to propagate along different rays and at different velocities, depending on their polarization. We found the law of motion for these signals along rays. We calculate the difference between the propagation times of electromagnetic signals with different polarizations from the same source to the detector. This difference is shown to reach a measurable value of 1 μs in some cases.