End state of the experimental black-hole bomb
Abstract
Rotating black holes can amplify incident waves through superradiant scattering. When these waves are confined, repeated amplification gives rise to the black-hole bomb instability, whose nonlinear evolution remains poorly understood despite its central role in models of bosonic clouds around astrophysical black holes. Here, we reproduce the black-hole bomb mechanism in a laboratory setting using a gravity simulator based on a draining vortex in superfluid helium. Surface waves propagating on the superfluid interface experience an effective rotating spacetime and undergo repeated superradiant amplification within a cylindrical cavity. By tuning the temperature and flow parameters, we achieve exponential growth of a low-frequency resonant mode, followed by the arrest of the instability and the formation of a long-lived non-equilibrium steady state. Using spatially and temporally resolved measurements, we identify nonlinear frequency shifts, harmonic generation, and coherent three- and four-wave mixing that redistribute energy among interacting modes. This novel end state of the experimental black-hole bomb highlights the role of nonlinear wave interactions in quenching the runaway growth expected from linear theory and governing the system's late-time dynamics. Our results establish a laboratory framework for investigating the nonlinear evolution of black-hole bombs, with implications for analogous phenomena involving ultralight bosonic fields around rotating black holes.
Related
- Quasinormal modes of Reissner-Nordström black hole from bound state spectrum
- Accretion onto a moving black hole for stiff equations of state
- Constraining equation of state of neutron star using neutron star-black hole mergers
- Final state of superradiant instability in Einstein-Maxwell-dilaton black hole
- Black hole equations of state and response functions
BibTeX
@misc{svancara2026state,
title = {{End state of the experimental black-hole bomb}},
author = {Patrik Švančara and Leonardo Solidoro and Pietro Smaniotto and Sam Patrick and Silvia Schiattarella and Maciej T. Jarema and Sean M. D. Gregory and Vitor S. Barroso and Maurício Richartz and Anastasios Avgoustidis and Carlo F. Barenghi and Ruth Gregory and Silke Weinfurtner},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.05595},
eprint = {2609.05595},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.05595},
}
RIS
TY - UNPB
TI - End state of the experimental black-hole bomb
AU - Patrik Švančara
AU - Leonardo Solidoro
AU - Pietro Smaniotto
AU - Sam Patrick
AU - Silvia Schiattarella
AU - Maciej T. Jarema
AU - Sean M. D. Gregory
AU - Vitor S. Barroso
AU - Maurício Richartz
AU - Anastasios Avgoustidis
AU - Carlo F. Barenghi
AU - Ruth Gregory
AU - Silke Weinfurtner
PY - 2026
DA - 2026/09/04
PB - arXiv
DO - 10.48550/arxiv.2609.05595
UR - https://arxiv.org/abs/2609.05595
AB - Rotating black holes can amplify incident waves through superradiant scattering. When these waves are confined, repeated amplification gives rise to the black-hole bomb instability, whose nonlinear evolution remains poorly understood despite its central role in models of bosonic clouds around astrophysical black holes. Here, we reproduce the black-hole bomb mechanism in a laboratory setting using a gravity simulator based on a draining vortex in superfluid helium. Surface waves propagating on the superfluid interface experience an effective rotating spacetime and undergo repeated superradiant amplification within a cylindrical cavity. By tuning the temperature and flow parameters, we achieve exponential growth of a low-frequency resonant mode, followed by the arrest of the instability and the formation of a long-lived non-equilibrium steady state. Using spatially and temporally resolved measurements, we identify nonlinear frequency shifts, harmonic generation, and coherent three- and four-wave mixing that redistribute energy among interacting modes. This novel end state of the experimental black-hole bomb highlights the role of nonlinear wave interactions in quenching the runaway growth expected from linear theory and governing the system's late-time dynamics. Our results establish a laboratory framework for investigating the nonlinear evolution of black-hole bombs, with implications for analogous phenomena involving ultralight bosonic fields around rotating black holes.
ER -