Seminarium Teorii Względności i Grawitacji

Recent observation of the shadow of the Messier 87 (M87) galactic center by the Event Horizon Telescope (EHT) group has triggered a great interest to investigate the causal structure of spacetime around the galactic center. From the recent investigations on gravitational lensing, it is now established that the shadow is not the signature of a black hole alone, it can also be cast by timelike or nulllike naked singularities in the presence of a photon sphere. In my talk, I will show a naked singularity, even without a photon sphere, can cast a shadow. I will show some distinguishable features of the shadow cast by timelike and nulllike naked singularities in the absence of the photon sphere. These novel features of the shadows of nulllike and timelike naked singularities may help us to distinguish between black holes and naked singularities observationally.Zoom Meeting ID: 814 7211 6408Passcode: 795365