The eye of the storm: Optical properties

Abstract

Investigation of the optical properties of a black hole described by the so-called “eye of the storm” space–time has been the main aim of the work. Such a space–time is regular and recovers the Minkowski space–time at asymptotical infinity due to the effect of the so-called “suppression parameter” involved in the metric. It has been shown that an increase in the suppression parameter reduces the inclination angle of photons in the close regions around a black hole due to gravitational lensing. Investigation of the photon motion has also shown that bigger values of this parameter reduce the photon sphere radius as well. It has been also detected that the shape of a black hole shadow is affected in the presence of the suppression parameter and the bigger values of this parameter twist the shape of a shadow stronger. Lastly, it has been demonstrated that the average shadow radius is bigger for smaller suppression parameters and the distortion of the shape of shadow from a circle is bigger for bigger suppression parameters and bigger spin of a black hole.