When you think of a particle accelerator, you
might imagine a vast underground tunnel like the Large Hadron Collider (LHC)
near Geneva—smashing protons together at incredible speeds to unlock the
secrets of the universe. But what if the universe itself has already built far
more powerful accelerators? That’s the bold idea behind a fascinating new study
published in Physical Review Letters by astrophysicists Andrew Mummery
and Joseph Silk.
Their paper, titled “Black Hole
Supercolliders”, proposes that certain spinning black holes could act as
natural particle accelerators—driving collisions at energies far beyond
anything we can build on Earth.
The Power
of Spin: Kerr Black Holes
The key to this cosmic phenomenon lies in the
nature of Kerr black holes. These are black holes that rotate, dragging
the very fabric of spacetime around with them. The faster they spin, the more
extreme this effect becomes. In particular, when a black hole is spinning near
its theoretical limit—what physicists call nearly extremal—its
gravitational field becomes an incredibly powerful engine for accelerating
matter.
Mummery and Silk explore what happens when particles fall into such a spinning black hole from two different directions. One comes from far away, pulled in by gravity. The other originates from a thin disk of matter spiraling inward—but moving in the opposite direction of the black hole's spin (a retrograde orbit (an orbit where an object moves in the opposite direction of the primary body it's orbiting, such as a satellite orbiting a planet in the opposite direction of the planet's rotation.)).
Natural Particle Collisions at 100 TeV
When these two particles—falling in opposite
directions at extreme speeds—collide near the event horizon, they do so with
astonishing energy. According to the researchers, the center-of-mass energy
of such collisions can reach tens to hundreds of tera-electronvolts (TeV).
That’s more than an order of magnitude greater than what the LHC can achieve
(around 14 TeV).
In effect, this setup transforms a spinning
black hole into a natural supercollider, running without any human
intervention, powered purely by gravity and spacetime itself.
Could We
Detect This?
So if the universe is smashing particles
together at energies beyond our wildest dreams… can we actually see the
results?
Possibly, yes. These high-energy collisions
could produce detectable signals—particularly neutrinos, elusive
particles that can travel vast distances without being absorbed. Detectors like
IceCube in Antarctica and KM3NeT in the Mediterranean Sea are
designed to capture such neutrinos. If we can trace some of them back to
spinning black holes with the right conditions, we might be observing the
afterglow of these extreme cosmic collisions.
A New Lab
for Extreme Physics
This discovery opens up thrilling
possibilities for science. Black holes could serve as natural laboratories for testing
physics at energy scales unreachable by human technology. That includes
probing the nature of dark matter, the behavior of gravity in extreme
conditions, and perhaps even hints of quantum gravity—the elusive theory that
unites Einstein’s relativity with quantum mechanics.
And unlike human-built accelerators, black holes don’t require funding proposals, construction crews, or years of upgrades. They’ve been at work for billions of years.
The idea of a black hole acting as a
supercollider may sound like science fiction, but this study places it firmly
in the realm of astrophysical reality. If such collisions are happening—and the
byproducts are escaping into space—they could offer one of the most exciting
new frontiers in modern astronomy and high-energy physics.
The universe might already be doing the experiments we dream of. Now, it’s up to us to watch closely—and try to understand the results.
Reference : Black Hole Supercolliders – Phys. Rev. Lett. 134, 221401 (2025)
