arXiv subjects

A. Ianniccari

Publications and source records attributed to A. Ianniccari.

6 recordsLinked to original sources

arXiv2026

Black Hole Mergers as the Fastest Photon Ring Scramblers

Black holes are the most efficient scramblers in nature. By mapping the instantaneous mass and angular momentum of two spinless black holes in a quasi-circular binary onto those of an effective Kerr black hole, we demonstrate that the final state of the merger remnant corresponds with remarkable accuracy to the configuration that renders null geodesics unstable at the highest possible rate. This suggests a deep connection between the properties of black holes resulting from binary mergers and their unstable null orbits.

gr-qc↗

arXiv2025

Nonlinear Gravity and Multipole Turbulence

We derive a kinetic Boltzmann equation characterizing the long-term statistical behavior of the turbulent dynamics of nonlinear interacting gravitational wave multipoles in Minkowski spacetime and show that, injecting a large number of gravitons with large multipoles drives the system toward an inverse multipole cascade at large times.

gr-qc↗

arXiv2025

The Nonlinear Tails in Black Hole Ringdown: the Scattering Perspective

Black holes regain their static configuration by emitting ringdown gravitational waves, whose amplitude decays in time following a power law at fixed spatial positions. We show that the nonlinear decay power law may be obtained by simple scattering calculations using the in-in formalism and argue that the nonperturbative law should be $t^{-2\ell-1}$, where $\ell$ is the multipole of the propagating spherical gravitational wave.

gr-qc↗

arXiv2025

The Irrelevance of Primordial Black Hole Clustering in the LVK mass range

We show that in realistic models where primordial black holes are formed due to the collapse of sizeable inflationary perturbations, their initial spatial clustering beyond Poisson distribution does not play any role in the binary mergers, including sub-solar primordial black holes, responsible for the gravitational waves detectable by LIGO-Virgo-KAGRA. This is a consequence of the existing FIRAS CMB distortion constraints on the relevant scales. This conclusion might not hold for lighter masses potentially accessible by future gravitational wave observations.

astro-ph.CO↗

arXiv2024

Deciphering the Instability of the Black Hole Ringdown Quasinormal Spectrum

The spectrum of the quasinormal modes of the gravitational waves emitted during the ringdown phase following the merger of two black holes is of primary importance in gravitational astronomy. However, the spectrum is extremely sensitive to small disturbances of the system, thus potentially jeopardizing the predictions of the gravitational wave observables. We offer an analytical and intuitive explanation of such an instability and its properties based on the transfer matrix approach of quantum mechanics. We also give a simple interpretation of the fact that the prompt ringdown response in the time domain and the black hole greybody factor receive parametrically small corrections, thus being robust observables.

gr-qc↗

arXiv2024

The Primordial Black Hole Abundance: The Broader, the Better

We show that the abundance of primordial black holes, if formed through the collapse of large fluctuations generated during inflation and unless the power spectrum of the curvature perturbation is very peaked, is always dominated by the broadest profile of the compaction function, even though statistically it is not the most frequent. The corresponding threshold is therefore 2/5. This result exacerbates the tension when combining the primordial black hole abundance with the signal seen by pulsar timing arrays and originated from gravitational waves induced by the same large primordial perturbations.

astro-ph.CO↗