The universe's early days may have played a crucial role in the formation of supermassive black holes, but new research suggests that this process was not sustainable in the long term. The study, published in the arXiv preprint server, explores the idea that black holes could have grown rapidly during a specific period in the early universe, known as the cosmic dark age. This period, which occurred after electrons and nuclei cooled to form atoms but before the first stars ignited, is believed to be when galaxies and supermassive black holes began to take shape.
The research team developed sophisticated hydrodynamic models to simulate the formation of black holes during this era. They discovered a phenomenon called the super-Eddington period, where regions around black holes were dense enough to allow superhot material to accumulate without being pushed away. This enabled black holes to grow at an accelerated rate, surpassing the typical Eddington Limit, which limits the growth of black holes today. However, this super-Eddington growth was only feasible up to a certain mass, approximately 10,000 solar masses.
The study's findings have significant implications for our understanding of the early universe and the formation of supermassive black holes. While this rapid growth phase might have contributed to the initial growth of black holes, it was not a sustainable process in the long run. The research suggests that black holes that grew at a sub-Eddington pace would eventually reach the same mass as those that experienced the super-Eddington growth. This finding challenges the idea that supermassive black holes formed solely through galactic mergers and hints at the possibility of seed mass black holes that formed very early in the universe, possibly during the inflationary period after the Big Bang.
