How Black Holes Actually Glow: A Simple Discovery express
A black hole is not just a vacuum cleaner. It glows faintly, emitting particles — this idea was proposed by Jacob Bekenstein, who connected the hole's temperature to its degree of disorder. Detecting such [tag:radiation]radiation in space is incredibly difficult.
Physicists set up a simple experiment: they fired a laser pulse through a glass fiber so fast that for light a "point of no return" appeared — like in a river with a current stronger than any swimmer. And they waited for "splashes" — quantum bursts, resembling a single splash from a stone in the rapids, not an avalanche. The previous explanation painted a tangled cascade, but nature turned out simpler.
But the main surprise is how ghostly this "simplicity" is. If a black hole weighed as much as the Sun, evaporation in such splashes would take longer than the age of the Universe multiplied by billions of billions. The light is there, but almost none of it. Perhaps someday, by catching particles from real holes, we will resolve the paradox of missing information.
Original abstract
as written by the authors arXiv:2607.01118
Hawking radiation - the emission of quantum particles at the event horizon of a black hole - connects gravity with quantum mechanics and thermodynamics; the Bekenstein-Hawking entropy has been the benchmark for potential quantum theories of gravity. But Hawking radiation has never been observed in astronomy, only in laboratory analogues and the chances of ever observing it in space are astronomically small. The energy of Hawking radiation must come from the gravitational field around the black hole, but how field quanta generate Hawking quanta has been unknown. Here we report on experimental and theoretical evidence for the process that generates Hawking radiation in a fibre-optical analogue of the event horizon. There, as in gravity, it has been believed that Hawking radiation comes from a complicated, cascaded process; here we have found a simple, direct process and measured its backreaction on the field. Our findings suggest an equally direct process for other laboratory analogues and perhaps also for gravitational fields, shedding light on how black holes might radiate.
If a black hole had the mass of the Sun, it would take it billions of billions of times longer than the age of the Universe to completely evaporate.