Neutrons, rotating black holes, and a galactic PeVatron at the center of the Milky Way

There's something almost poetic about calling black holes the "mitochondria" of the universe. Like those ancient bacterial stowaways that now power every cell in your body, supermassive black holes sit at the galactic center, quietly converting raw cosmic fuel into the energy that shapes everything around them. But the analogy only goes so far. Mitochondria burn glucose; black holes can do something far stranger—they can give up energy that was never theirs to begin with, energy locked in the spin of spacetime itself. That's the Penrose process, first dreamed up by Roger Penrose in 1969. Here's the mind-bending part: inside a rotating black hole's ergosphere, a region where space itself is dragged along so violently that nothing can stand still, a particle can split in two. One fragment falls into the black hole with *negative* energy—effectively owing the universe a debt—while the other escapes with more energy than the original particle possessed. The black hole slows down by a tiny amount; the escaping particle carries away stolen rotational energy. It's a cosmic version of getting rich by having your friend fall into a pit with your credit card. What makes this new study so tantalizing is the suggestion that this process might not be purely theoretical. The title alone—neutrons, rotating black holes, a galactic PeVatron—reads like a treasure map. Neutrons are the perfect messengers here: they're electrically neutral, so they aren't deflected by the Milky Way's magnetic fields on their journey to Earth. And a PeVatron is a source that accelerates particles to petaelectronvolt energies, a million billion electron volts, far beyond what any human-built collider can achieve. If the galactic center's supermassive black hole is spinning fast enough, the Penrose process could naturally produce neutrons at exactly these energies—and those neutrons could point straight back to their source like cosmic arrows. The deeper implication is almost vertigo-inducing. We tend to think of black holes as ultimate consumers, cosmic hoarders that swallow everything and give nothing back. But rotating black holes are different: they're reservoirs of energy, and the Penrose process suggests they can be tapped. The question is whether nature actually does the tapping on its own. If this study's signature is found, it would mean the universe has been running black-hole-powered accelerators all along, and the most extreme particles ever detected were born not from explosions or collisions, but from the slow, patient winding-down of spacetime itself. That's not just astrophysics—that's a revelation about what a black hole really is. Not a trap. A battery. As always, we should hold our excitement in check until the observations come in. But that's the beautiful thing about science: a fifty-year-old idea written on a chalkboard might just turn out to be the key to understanding the most violent fireworks in the galaxy. And the source article, available at [phys.org](https://phys.org/news/2026-10-neutrons-rotating-black-holes-galactic.html), gives us a front-row seat to the hunt.