Could black holes be the ultimate wall of nature? Could they be the most extreme objects and the most unknown? Are they the final stage of knowledge?
For years, black holes have been studied, first from the mathematical point of view, emerging from Albert Einstein’s General Relativity equations, and then from the observational point of view, given that we had a lot of indirect proofs of their existence but not yet a definite one. Up to 2019, when the Event Horizon Telescope collected the data used to release the first-ever image of the black hole in the galaxy M87, followed by that of the black hole inside our galaxy, Sagittarius A*. So, they exist and they do not represent only a “mysterious” mathematical solution anymore. But, what really are they?