Merging boson stars could explain massive black hole collision and prove existence of dark matter

An international team of scientists led by the Galician Institute of High Energy Physics (IGFAE) and the University of Aveiro shows that the heaviest black hole collision ever observed, produced by the gravitational-wave GW190521, might actually be something even more mysterious: the merger of two boson stars. This would be the first evidence of the existence of these hypothetical objects, which are a candidate for dark matter, believed to comprise 27% of the mass in the universe.