University of Western Ontario astrophysicists have discovered that emerging from a star remnant is not necessary for the direct formation of black holes.
There was previously no explanation for the distribution observed in supermassive black holes masses and luminosities. Shantanu Basu and Arpan Das from Western’s Department of Physics & Astronomy have developed the explanation for the direct formation of black holes which is published in Astrophysical Journal Letters.
According to Western University, the new model is based on that assumption that supermassive black holes form extremely quickly over very short periods of time and then stop suddenly. This is in contrast to the former understanding of how stellar mass black holes are formed, which was assumed to be caused by the centre of a very massive star collapsing in on itself.
The mathematical model works by calculating the mass function of supermassive black holes that form over a limited time period and experience a rapid exponential mass growth.
Black holes originate from direct-collapses
Basu, an astronomy professor at Western and expert in the early stages of star formation and protoplanetary disk evolution, said: “This is indirect observational evidence that black holes originate from direct-collapses and not from stellar remnants. Supermassive black holes only had a short time period where they were able to grow fast and then at some point, because of all the radiation in the universe created by other black holes and stars, their production came to a halt. That’s the direct-collapse scenario.”
According to Western University, the results evidences that direct-collapse black holes were produced in the early universe and Basu believes that more work must be done to prove the validity, but the new results can be used to infer the formation history of the extremely massive black holes that existed in the history of the early universe.