Magnetic field geometry in rotating wormhole spacetimes

Abstract

If a black hole is immersed in a magnetosphere,its rotational energy can be transferred to the electromagnetic field and escape as a Poynting flux to infinity. This process of extraction of rotational energy is known as the Blandford-Znajek mechanism. It relies on the presence of both a magnetosphere and an ergosphere surrounding the black hole. Previously, we showed that rotating wormholes are also capable of emitting a Poynting flux in the process of accreting magnetized matter. In this work, we re-examine the Blandford-Znajek mechanism in the case of a Kerr-type wormhole. For the first time, we solve the stream equation in a rotating wormhole spacetime and derive analytical expressions for the magnetic field. We then compute the associated Poynting flux. Our results indicate that the electromagnetic flux in the wormhole spacetime is weaker than in the Kerr case, and this difference becomes more pronounced as the geometries of the two spacetimes increasingly deviate.