There Could Be “Stupendously Large” Supermassive Black Holes Bigger Than Galaxies

What is the maximum size of a supermassive black hole (SMBH)? A new theory proposes incredibly massive, or, to use their more sophisticated terminology, “stupendously vast.” The goal of the endeavor was to establish some limitations on how massive these celestial things may go.

Researchers looked at the potential characteristics, genesis, and consequences of these stupendously big black holes, or SLABs, in a report that was published in the Monthly Notices of the Royal Astronomical Society. The researchers began by emphasizing that there is no proof that black holes larger than those seen at the centers of the most massive galaxies exist.

Despite the fact that we don’t know how SMBHs originate and there is speculation regarding a physical upper limit to their size, the idea of what lies beyond is intriguing. The size of the Milky Way to a million times the size of our galaxy would be the mass range for SLABs under consideration. The largest SMBH that we have ever identified is 25 times smaller than the bottom limit.

“We already know that black holes come in a wide range of masses, with our own galaxy’s SMBH being four million solar masses. SLABs may exist and may possibly dwell outside galaxies in intergalactic space, with fascinating observational repercussions, even though there is presently no proof of their existence. Surprisingly, the concept of SLABs has largely been ignored up until this point, according to the primary author, Professor Bernard Carr of the Queen Mary University of London.

“We’ve outlined potential formation scenarios for these SLABs and anticipate that our study will start to spur community debates.”

Since it is highly improbable that these things would expand in size throughout the course of the universe’s history, one theory is that they have always been. Black holes are thought to have formed more easily in the first few seconds following the Big Bang because of certain circumstances.

The existence of dark matter, the fast creation of supermassive black holes, and other unanswered mysteries about the universe have all been explained by reference to these primordial black holes. What constraints can we impose, though? The idea that these things developed everywhere and are widely dispersed throughout the cosmos is an intriguing one. The velocity of galaxies would be considerably affected by these large objects. With the use of these concepts and knowledge of the speed of the Milky Way, the team was able to determine that, even if just one of these SLABs existed, it would be the largest ever, with a mass that is around one billion times that of the Milky Way.

The impact of these primordial SLABs on the cosmic microwave background—the original source of light in the universe—is another restriction. That could be a more fair ranger to take into account as something 100 times bigger than the Milky Way would leave a noticeable mark. Although black holes are difficult to locate, these SLABs would have a significant gravitational impact. There haven’t been any reports of something similar, but perhaps there is a maximum size for black holes that we haven’t yet discovered.