Black hole mergers put limits on star-destroying supernovae

Recent analyses from a team of researchers have illuminated a fascinating aspect of black hole mergers, revealing a significant “mass gap” in the detected population of these cosmic entities. This finding suggests that certain massive stars undergo a dramatic fate known as a pair-instability supernova, a catastrophic event that obliterates the star and leaves only debris in its wake. As astronomers have turned their focus to the data from four gravitational wave detectors, they are beginning to unravel the formation processes of these celestial bodies. The collapse of a star's core during a supernova leads to the creation of black holes; while the outer layers explode outward, the core plunges inward, contributing a portion of the star's mass to the black hole or, in cases of lower mass, a neutron star. The theoretical models indicate an unexpected sharp transition in the distribution of black hole masses. Rather than a gradual decline, scientists propose that there exists an upper mass limit for stars. When the density of photons in a star's core reaches a critical point, their energy can convert into mass in the form of electron-positron pairs, leading to the formation of antimatter. This conversion significantly undermines the outward pressure that prevents the star's core from collapsing, resulting in a rapid compaction and the eventual explosive demise of the star. This groundbreaking research not only enhances our understanding of black hole formation but also opens new avenues for exploring the extreme conditions present in the universe's most massive stars.