"Universe Holds Mind-Boggling 40 Quintillion Black Holes"

Astrophysicists estimate that there are approximately 40 quintillion black holes in the Universe, which is 1-2% of all stars and higher than previous estimates. The number of black holes and their mass function is still being investigated, but data from gravitational wave detections by LIGO and Virgo have provided valuable insights. The uncertainties lie in the lowest black hole masses, but the overall black hole mass density is estimated to be about 10% of the stellar mass density in the Universe. If confirmed, black holes would comprise 0.04% of the cosmic energy budget, suggesting that conventional astrophysics may have given rise to the observed supermassive black holes throughout cosmic history.