Primordial black holes ruled out as a major dark matter source
New calculations suggest that even if 'stupendously large' primordial black holes exist, they cannot account for a significant portion of the universe's dark matter.
Hypothetical "stupendously large" primordial black holes, formed in the early universe, have been ruled out as a significant source of dark matter. New calculations by researchers indicate that even if these objects exist, they cannot constitute a meaningful fraction of the universe's elusive dark matter.
These primordial black holes are theorized to be at least 100 billion times the mass of the sun. The study analyzed how their random distribution throughout space would affect the balance between matter and radiation. The researchers compared their predictions to measurements of the cosmic microwave background, the afterglow of the Big Bang.
The findings suggest that a substantial population of such black holes would create noticeable patterns in the cosmic microwave background that are not observed. This also challenges theories that these black holes might have seeded early galaxies. While the study does not entirely dismiss the existence of primordial black holes in this mass range, it places tight new limits on their potential contribution to dark matter.
Source: Phys.org