Shadow of charged wormholes in Einstein-Maxwell-dilaton theory

摘要

The study of shadow is quite prominent nowadays because of the ongoing Event Horizon Telescope(1) observations. We construct the shadow images of charged wormholes in Einstein-Maxwell-dilaton (EMD) theory. The spacetime metric of the charged wormholes contains three charges: magnetic charge P, electric charge Q, and dilaton charge Sigma. We evaluate the photon geodesics around the charged wormholes. We also calculate the effective potential and discuss its behavior with angular momentum L and different values of charges P, Q, and Sigma. A study of the shadow of charged wormholes reveals that the shadow has an effect of the charges P and Q. The radius of the shadow increases with the magnetic charge P as well as the electric charge Q. We also find that the dilaton charge does not affect the shadow of the charged wormholes. (C) 2018 Elsevier Inc. All rights reserved.