On the force caused by a null Einstein-Maxwell field with the plane symmetry

The article shows that a large flat platform with a constant current, which flows over its surface, accelerates time. It is also shown that if an alternating current flows along the surface of a flat platform while creating a null electromagnetic field then a force repelling from the platform acts on the test particle located near it. This force has no gravitational nature and arises as a result of the curvature of space-time by the electromagnetic field of a flat platform with an alternating current.

Null electromagnetic fields and relative Cauchy–Riemann embeddings

This paper applies the notion of relative Cauchy–Riemann (CR) embeddings to study two related questions. First, it answers negatively the question posed by Penrose whether every shear-free null rotating congruence is analytic. Second, it proves that, given any shear-free null rotating congruence in Minkowski space, there exists a null electromagnetic field that is null with respect to the given congruence. In the course of answering these questions, we introduce some new techniques for studying null electromagnetic fields and shear-free congruences, in general, based on the notion of a relative CR embedding.