Affiliation: University of Tübingen, Germany
Title: Black holes in general relativity and beyond
Abstract: LIGO-Virgo collaborations detectors observed the first direct detection of gravitational waves, representing the first observation of a black hole merger. In addition, the Event Horizon Telescope released the first direct image of a black hole associated with the supermassive black hole that lies in the center of the Messier 87 galaxy. Therefore, despite black holes being initially considered purely theoretical objects, there is now substantial observational evidence supporting their existence. Black holes do not emit radiation directly, but there are some physical mechanisms that can serve as sources of radiation associated with a black hole. In particular, due to its powerful gravitational field, the accretion disk of a black hole is hot enough to emit X-rays just outside the event horizon. On the other hand, Hawking radiation is a theoretical idea suggesting that quantum effects near the event horizon can generate emission of of thermal black-body radiation. In this talk, I will address these aspects in the context of general relativity and discuss some basic topics of particular modified gravity theories as well as solutions describing black holes.
Affiliation: SISSA, Italy