Group 1 - An international collaboration team has detected the largest black hole merger event to date, which is significant for understanding the growth of black holes in the universe [1] - The merger event, named GW231123, involved two black holes with masses approximately 100 and 140 times that of the Sun, resulting in a new black hole with a mass of about 225 times that of the Sun [1] - The black holes involved in the GW231123 event have a rapid spin rate of about 40 times per second, nearing the limits predicted by Einstein's general relativity [1] Group 2 - Black holes are categorized into three types based on mass: stellar black holes (a few to 100 solar masses), supermassive black holes (millions of solar masses), and intermediate black holes, which are rare [2] - Most events captured by LIGO involve stellar black holes formed from the collapse of massive stars, but the GW231123 event's black holes exceed the stellar black hole range, suggesting alternative formation mechanisms [2] - A possible explanation for the formation of the black holes in the GW231123 event is that they may have originated from the merger of earlier smaller black holes, which would increase their spin and mass [2]