Cosmic coupling
As I wrote in my blog "on a rubber mat" the gravitational waves are vibration of the spacetime medium and they emerge notably from comic collisions like black hole merges. Since the first observation of merging black holes by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015, astronomers have been repeatedly surprised by their large masses. A star with a mass under 40 Suns can collapse to a black hole but not heavier ones. However, mergers of black holes with mass as much as 100 Suns are discovered. Recently, a research group in University of Hawaii published a study in Astrophysical Journal Letters about cosmic coupling explaining gravitational wave observations of the past years. Their hypothesis is that mass of black holes grow while the universe expands. The research group simulated millions of evolved black holes that were modeled in the expanding universe instead of static. Whereas conventional black hole models are simplifications of Einstein's