No direct evidence for the existence of Black Holes
By their very nature, black holes do not directly emit any signals other than the hypothetical Hawking radiation; since the Hawking radiation for an astrophysical black hole is predicted to be very weak, this makes it impossible to directly detect astrophysical black holes from the Earth. A possible exception to the Hawking radiation being weak is the last stage of the evaporation of light (primordial) black holes; searches for such flashes in the past have proven unsuccessful and provide stringent limits on the possibility of existence of light primordial black holes. NASA’s Fermi Gamma-ray Space Telescope launched in 2008 will continue the search for these flashes.
Astrophysicists searching for black holes thus have to rely on indirect observations. A black hole’s existence can sometimes be inferred by observing its gravitational interactions with its surroundings. A project run by MIT’s Haystack Observatory is attempting to observe the event horizon of a black hole directly.
According to the standard model for star formation, gas clouds from which stars form should have been ripped apart by tidal forces from the supermassive black hole. Evidently, the gravity of a dense disk of gas around Sagittarius A* offsets the tidal forces and allows stars to form. The tug-of-war between the black hole’s tidal forces and the gravity of the disk has also favored the formation of a much higher proportion of massive stars than normal.
Chandra: “Stars Surprisingly Form in Extreme Environment Around Milky Way’s Black Hole“
When observation contradicts the gravity only cosmology the result is to immediately ‘morph’ the supposed gravitational characteristics of the ever pliable theoretical black hole. It is habitually done on autopilot.