Direct imaging of black holes in modified gravity and cosmology (presentación oral, expositor plenario invitado)

ERNESTO F. EIROA

Valparaíso

Conferencia; CosmoSur V; 2019

Universidad de Valparaíso y Pontificia Universidad Católica de Valparaíso, Chile

The international collaboration Event Horizon Telescope (EHT) have recently presented the first image, in millimeter radio waves (230 GHz), of the close environment of the supermassive black hole located at the center of the elliptical galaxy M87. It clearly shows the presence of the so-called shadow, surrounded by the light coming from the accretion disk around the black hole. In this talk, a summary of the historical developments and the theoretical aspects of the subject is presented, and the main results of the observation made by EHT are shown. Then, some recent advances in the study of the shadows of rotating black holes in modified gravity and cosmology are introduced. In this case, the size and the shape of the shadow which always depend on the mass and the angular momentum of the black hole, are also related with other parameters specific of the particular model adopted. Finally, the differences with the Kerr counterpart in general relativity and the future observational prospects are discussed.