Related papers: Clocking Out Superradiance Limits
One of the theoretical motivations behind the belief that black holes as described by general relativity exist in nature is that it is hard to find matter configurations that mimic their properties, especially their compactness. One of the…
Ultralight scalars can form superradiant clouds around rotating black holes. These may alter the dynamics of compact binaries and the ensuing waveform through orbital resonances and cloud ionization. We re-examine resonances involving…
Through the black hole (BH) superradiance, ultralight bosons can form dense clouds around rotating Kerr BHs. Certain ultralight bosons, such as axions and axion-like particles (promising dark matter candidates), naturally possess…
Recent fully non-linear simulations of ultracompact spherically symmetric boson stars have presented evidence for their long-term stability. All observed dynamics could be mainly attributed to the fundamental radial mode. In this work, we…
Electromagnetic field confinement due to plasma near accreting black holes can trigger superradiant instabilities at the linear level, limiting the spin of black holes and providing novel astrophysical sources of electromagnetic bursts.…
Ultralight bosons can affect the dynamics of spinning black holes (BHs) via superradiant instability, which can lead to a time evolution of the supermassive BH shadow. We study prospects for witnessing the superradiance-induced BH shadow…
Gravitational signatures of black hole superradiance are a unique probe of ultralight particles that are weakly-coupled to ordinary matter. The existence of an ultralight boson would lead spinning black holes with size comparable to the…
We study collisions of massive pointlike particles in three dimensional anti-de Sitter space, generalizing the work on massless particles in [1]. We show how to construct exact solutions corresponding to the formation of either a black hole…
Supermassive Black Holes are the most entropic objects found in the universe. The Holographic Bound (HB) to the entropy is used to constrain their formation time with initial masses $\sim{10}^{6-8}M_{\odot}$, as inferred from observations.…
Fundamental bosonic fields of arbitrary spin are predicted by generic extensions of the Standard Model and of General Relativity, and are well-motivated candidates to explain the dark components of the Universe. One of most promising…
Axion stars, gravitationally bound states of low-energy axion particles, have a maximum mass allowed by gravitational stability. Weakly bound states obtaining this maximum mass have sufficiently large radii such that they are dilute, and as…
The supermassive black holes observed at the centers of almost all present-day galaxies, had a profound impact on their environment. I highlight the principle of self-regulation, by which supermassive black holes grow until they release…
Following Ruffini and Bonazzola, we use a quantized boson field to describe condensates of axions forming compact objects. Without substantial modifications, the method can only be applied to axions with decay constant, $f_a$, satisfying…
Black hole superradiance is a powerful probe of ultralight axions. If nature contains a boson with a mass of order $10^{-12}\,$eV, $\textit{mere vacuum fluctuations}$ will lead to its efficient production around spinning stellar mass black…
We study the imprints of new ultralight particles on the gravitational-wave signals emitted by binary black holes. Superradiant instabilities may create large clouds of scalar or vector fields around rotating black holes. The presence of a…
We study the evolution of perturbations during the domination and decay of a massive particle species whose mass and decay rate are allowed to depend on the expectation value of a light scalar field. We specialize in the case where the…
The naturalness problem of PQ symmetry motivates study of the heavy QCD axion, with masses $m_a >$ 1 MeV generated at scales above the QCD scale, and low values of the PQ symmetry breaking scale, $f_a$. We compute the abundance of such…
We study the evolution of black hole collisions and ultraspinning black hole instabilities in higher dimensions. These processes can be efficiently solved numerically in an effective theory in the limit of large number of dimensions D. We…
Using series solutions and time-domain evolutions, we probe the eikonal limit of the gravitational and scalar-field quasinormal modes of large black holes and black branes in anti-de Sitter backgrounds. These results are particularly…
It has been argued that the rate at which the interior of an AdS black hole evolves is dual to the rate of evolution of the (quantum state of the) strongly coupled matter on the boundary which, according to holography, is dual to the black…