  Our understanding of strong gravity near supermassive compact objects has
recently improved thanks to the measurements made by the Event Horizon
Telescope (EHT). We use here the M87* shadow size to infer constraints on the
physical charges of a large variety of nonrotating or rotating black holes. For
example, we show that the quality of the measurements is already sufficient to
rule out that M87* is a highly charged dilaton black hole. Similarly, when
considering black holes with two physical and independent charges, we are able
to exclude considerable regions of the space of parameters for the
doubly-charged dilaton and the Sen black holes.

General Relativity and Quantum Cosmology