A team of astrophysicists has announced that black holes, regardless of size, follow a single universal rule when they erupt — and the rule, the researchers say, is that they erupt when they are slightly hungry.
The finding, published in Nature Astronomy and led by work at Curtin University, shows that a small black hole and a supermassive one — the latter often millions of times heavier — fire their famous plasma jets at the exact same moment in their feeding cycle: when the rate at which they are being fed drops to roughly 2 percent of the theoretical maximum.
In plain terms, a black hole does not burp when it is full. It burps when it is no longer being fed fast enough, a distinction the research team delivered with the gravity the subject requires.
“We found that the jets turn on at a critical feed rate,” the research team explained in a summary of the work, in language that managed to be both precise and, for a black hole, faintly passive-aggressive. “Below it, no jets. Above it, jets. The mass of the object does not matter.”
This is the part that excited physicists. The universe, it turns out, has a rule that works the same way for a stellar-mass object as for a monster at the center of a galaxy — a universality so clean it is almost rude.
Dr. Lena Okafor, an astrophysicist who was not involved in the study and who asked to be quoted because she finds it “obscene,” put it this way: “We’ve had a hundred models. This one says the answer was a number. A single number. The cosmos ran the whole jet program off a feed-rate threshold and never told anyone.”
The result does not explain how to build a faster-than-light drive, answer questions about the origin of life, or help anyone feel better about their own eating schedule, and the researchers were firm on all three points.
It does mean that when astronomers see a jet from a black hole billions of light-years away, they can now say with confidence that the object was, at that moment, underfed — a finding that has made the study the first in cosmology to be described in the comments section as “relatable.”
The team is now testing the rule on more objects — the scientific term for asking the universe the same question again to see if it was bluffing.