A host of supermassive black holes populating the universe during the cosmic dark ages appears to drastically exceed estimates for how many billion-solar-mass black holes should have existed back then. The surprising find is the result of a 14-year study conducted with the Hubble Space Telescope.
The study team, led by Matthew Hayes of Stockholm University, searched for these early supermassive black holes by scouring the Hubble Ultra Deep Field for any faint objects that seem to exhibit variable brightness.
