Study finds largest black holes grow through repeated cluster collisions
Technology
A new study just revealed that the universe's biggest black holes probably aren't born in one go: they grow bigger by crashing into each other again and again inside crowded star clusters.
This challenges the old idea that they come straight from massive stars collapsing.
Black hole spins diverge above 45-solar-mass
By studying 153 black hole mergers detected by LIGO, Virgo, and KAGRA, researchers found that smaller black holes spin slowly and in sync (like they were "born" neatly), while the larger ones have wild, random spins, clear signs of multiple collisions.
The team also spotted a mass threshold around 45 times the sun; above this, black holes likely grew through repeated smash-ups rather than forming directly.