New experiments are bringing into focus the mechanism behind Hawking radiation, the strange phenomenon that demonstrates black holes are not strictly a one-way street.
While theoretical physicist Stephen Hawking’s prediction of this faint radiation from black holes has yet to be detected from space, researchers have replicated it in laboratory models and have developed complex theories to explain the phenomenon.
In their recent paper in Nature, an international team of researchers from Germany’s Paderborn University, Mexico’s Cinestav, and Israel’s Weizmann Institute of Science has developed laboratory models that may point to a much simpler mechanism underlying these theoretical black hole emissions.
Hawking Radiation
Stephen Hawking first described Hawking radiation in a 1974 theoretical model, characterizing this as a type of blackbody radiation, meaning it is in thermodynamic equilibrium with its environment and changes with the body’s temperature. His prior work had assumed that the pull of a black hole was so powerful that electromagnetic radiation could not escape it. But eventually he reconsidered the work of two Soviet scientists, Yakov Zeldovich and Alexei Starobinsky, who proposed in 1971 that black holes could create and emit particles.
A major consequence of this theoretical radiation is that if it were real, it would mean that black holes slowly evaporate as they lose electromagnetic radiation. Given enough time, if a black hole failed to feed, it would continue to shrink until it vanished entirely.
Intriguingly, the rate at which this happens would be inversely proportional to the black hole’s mass, with smaller black holes emitting radiation at a faster rate. Therefore, micro black holes could disappear remarkably quickly compared to their larger siblings.
Modeling Black Hole Emissions
The international team’s work models the generation of Hawking radiation in a nonlinear optical environment, allowing them to identify a simple mechanism responsible for the emission and its impact on the system.
Earlier work described a significantly more complicated scenario, involving multiple quantum-mechanical processes interacting in a cascade to generate the Hawking radiation. The new solution utilized a fiber-optic model of a black hole’s event horizon, combined with precision experiments and rigorous modeling to reveal a much simpler mechanism by which radiation generates and feeds back.
“This simplifies the theoretical understanding and opens up new ways of calculating effects in such systems,” explained lead author Dr. Lorenzo M. Procopio, formerly of Weizmann but now of Paderborn University. “It might even shed light on how Hawking radiation arises in the context of gravity.”
Experimental Verification
The international researchers’ work goes beyond identifying the simplified mechanism; it also provides evidence that Hawking radiation interacts with the black hole system, rather than passively emitting from it into space.
Understanding this emission system is crucial to one of the great unanswered questions about black holes: do they lose mass over time or remain in permanent equilibrium? The enormous cosmic scale of a black hole and massive distances involved make such a precise study out of reach for current observational technology.
However, this laboratory work provides a unique opportunity to study the effect of Hawking radiation on a measurable scale. Additionally, Hawking radiation experiments offer essential clues to the nature of elusive quantum gravity, in which physicists are still trying to determine how macroscopic gravity impacts the microscopic quantum world.
The paper, “Backreaction of Stimulated Hawking Radiation in an Optical Analogue,” appeared in Nature on July 1, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.