Popular Science Kainaati Gup Shup: Evidence for Black Holes (Urdu) Dr. Salman Hameed April 11, 2019 Black holes are one of the most mysterious objects in the universe. If even light cannot escape the gravitational pull of black holes, then how do we know they are even there? For the answer, please watch Kainaati Gup Shup with astrophysicist, Dr. Salman Hameed, and subscribe to Kainaat Astronomy.