Physicists Just Recreated a Black Hole's Energy-Extraction Trick - On a Lab Bench

Fifty years ago, one of the strangest ideas in physics said you could steal energy from a spinning black hole. This month, a team in New York reproduced the essential physics on a lab bench - no black hole, no gravity, and nothing actually spinning. Writing in Nature, physicists at the City University of New York's Advanced Science Research Center (CUNY ASRC) showed that a cleverly engineered ring of electronic resonators can amplify a wave by pulling energy out of a purely synthetic rotation - a traveling pattern that behaves as if it were spinning faster than light. It is a tabletop echo of a cosmic phenomenon that has fascinated theorists since the days of Roger Penrose.

1. Penrose's 1969 idea: energy from a spin

Start with the theory. A rotating black hole drags spacetime around with it, creating a region just outside the event horizon called the ergosphere, where nothing can sit still - everything is forced to co-rotate. In 1969, mathematical physicist Roger Penrose (who later shared the 2020 Nobel Prize in Physics for his black-hole work) pointed out something remarkable about this zone: if an object entering the ergosphere splits into two, one fragment can fall into the black hole carrying negative energy, while the other escapes carrying more energy than the whole object had going in.

Energy is still conserved - the surplus is quietly drawn out of the black hole's rotation, slowing its spin by a hair. In principle, a sufficiently patient civilization could power itself for eons by mining a black hole's spin. It became known as the Penrose process.

2. Zel'dovich's twist: make it a wave

Two years later, Soviet physicist Yakov Zel'dovich asked what happens if you replace the particle with a wave. His 1971 answer: a wave that strikes a rotating, absorbing body will bounce back amplified - carrying away some of the body's rotational energy - provided one condition is met. The body has to be spinning fast enough that, from the wave's point of view, the surface is rushing forward faster than the wave's own rotation. Physicists call this effect rotational super-radiance.

In 1972, William Press and Saul Teukolsky took it to its logical extreme: wrap a mirror around such a system so the wave bounces back and forth, gaining energy on every pass, and you get runaway growth - a scenario they nicknamed the “black-hole bomb.” (It is a thought experiment about amplification, not a weapon.) The trouble, for anyone hoping to see this in a lab, is that “fast enough” is genuinely, absurdly fast.

3. The trick: rotation without spinning

Here is the CUNY team's insight. You do not actually need to spin anything - you only need the system to behave as though something is spinning past the wave. So instead of a rotor, they built a ring of electronic resonators and changed each one's properties in a rapid, carefully choreographed sequence around the loop. The result is a modulation pattern that travels around the ring - a “synthetic rotation” - even though every component stays bolted in place.

Because this rotation is just a pattern, not moving matter, it can be pushed into regimes real objects can never reach. In particular, the effective rotation can mimic speeds faster than light without anything material breaking that cosmic speed limit - exactly the condition Zel'dovich needed. The paper's title names the mechanism precisely: Floquet refers to the time-periodic driving of the resonators, the engine of the whole effect.

4. What they saw

When the researchers sent electromagnetic waves into the ring, the waves carrying the right rotational signature - the ones whose twist matched the synthetic rotation - drew energy out of the system and emerged stronger. The amplification was broadband and selective: it boosted waves with the correct rotational character while leaving others alone. That is the fingerprint of super-radiance, reproduced with light and electronics rather than gravity and starlight.

“Our approach facilitates a new method of wave-matter interaction in which waves with selected rotational properties extract energy from synthetic time-engineered rotation, producing a form of broadband selective amplification,” said Andrea Alu, the project's principal investigator and founding director of the CUNY ASRC Photonics Initiative.

Analog experiments had glimpsed related physics before - notably a 2020 University of Nottingham study that watched water waves get amplified by a draining vortex. What sets the CUNY result apart is that its rotation is fully engineered and tunable, on an electromagnetic platform, reaching into regimes no spinning fluid or solid could.

5. Why it matters (beyond the wow)

• A new kind of amplifier. Pulling energy from engineered, time-modulated rotation is a genuinely new way to boost a signal. The team points to uses in wireless communications, optics, photonics, and quantum technologies, where compact, frequency-selective amplification is valuable.
• A laboratory for the extreme. Synthetic rotation lets physicists stage conditions - including effective motion faster than light - that are impossible with real rotating matter, giving them a controllable bench to test ideas from astrophysics and relativity.
• A bridge between fields. As lead author Hadiseh Nasari put it, the platform sits “at the intersection of astrophysics, wave physics, and quantum science” - a rare piece of hardware that speaks to all three.

What we still don't know

• How far the gain can be pushed before the modulated system runs into practical limits or instabilities.
• Which application lands first - a real-world amplifier, a sensor, or a testbed for exotic physics.
• How closely the analog can track true astrophysical super-radiance, including the quantum version thought to let even non-rotating vacuum fluctuations seed radiation around black holes.

Sources

• Nasari, Moussa, Kasahara, Thielens, Alu, “Observation of Floquet rotational super-radiance,” Nature (2026), DOI 10.1038/s41586-026-10725-y
• EurekAlert / CUNY ASRC: A black-hole theory comes to life in the lab · ScienceDaily: Physicists recreate black-hole energy extraction in the lab
• Phys.org: Synthetic rotation brings black-hole energy theory into the lab
• Background: R. Penrose (1969) on the Penrose process; Ya. B. Zel'dovich (1971) on rotational super-radiance; W. Press & S. Teukolsky, “Floating Orbits, Superradiant Scattering and the Black-hole Bomb,” Nature 238, 211 (1972).

Curated by Jerry Cards - jerrycards.com. We research the week's most consequential tech, science, and business news so you don't have to. More at jerrycards.com/news.