For Quanta Magazine, Steve Nadis explained how solutions to certain Einstein’s equations prove that ‘a spinning black hole won’t blow up, even when poked or prodded‘ via a new paper:

In a 912-page paper posted online on May 30, Szeftel, Elena Giorgi of Columbia University and Sergiu Klainerman of Princeton University have proved that slowly rotating Kerr black holes are indeed stable. The work is the product of a multiyear effort. The entire proof — consisting of the new work, an 800-page paper by Klainerman and Szeftel from 2021, plus three background papers that established various mathematical tools — totals roughly 2,100 pages in all.

The new result “does indeed constitute a milestone in the mathematical development of general relativity,” said Demetrios Christodoulou, a mathematician at the Swiss Federal Institute of Technology Zurich.

Shing-Tung Yau, an emeritus professor at Harvard University who recently moved to Tsinghua University, was similarly laudatory, calling the proof “the first major breakthrough” in this area of general relativity since the early 1990s. “It is a very tough problem,” he said. He did stress, however, that the new paper has not yet undergone peer review. But he called the 2021 paper, which has been approved for publication, both “complete and exciting.”

Who the hell goes around poking black holes though?