742 citations · 3.9k across the 49 of their papers we have counts for
51 papers
The quasinormal modes of Kerr-Newman black holes: a separated approach
Kyriakos Destounis, Vitor Cardoso, Peter Hintz
We compute Kerr-Newman quasinormal modes using a recently found exact separation of the gravitoelectric perturbation equations. For each spin-label , a matrix angular ordin…
Chaotic signatures in extreme-mass-ratio systems surrounded by bosonic environments
Qi-Xuan Xu, Kyriakos Destounis, Yin-Da Guo +2
Extreme-mass-ratio inspirals are key gravitational-wave sources for testing strong gravity and the environments of massive black holes. While orbital motion in Kerr black hole spac…
Tidally-enhanced resonances in extreme-mass-ratio inspirals: A tertiary path to chaos
Kyriakos Destounis, Takuya Katagiri, Sajal Mukherjee +1
Extreme-mass-ratio inspirals (EMRIs) provide a unique laboratory for probing strong-field gravity and complex relativistic dynamics. We study a tidally deformed EMRI composed of a…
Spectral instability of horizonless compact objects within astrophysical environments
Kyriakos Destounis, Mateus Malato Corrêa, Caio F. B. Macedo +1
Recent non-modal analyses have uncovered spectral instabilities in the quasinormal-mode spectrum of black holes; a phenomenon that intriguingly extends to spherically-symmetric exo…
Overdamped quasibound states inside a Schwarzschild black hole
Jeff Steinhauer, Kyriakos Destounis, Richard Brito
Schwarzschild black-hole interiors, bounded by event horizons and terminated by spacelike singularities, are regions where all physical observers are inevitably destroyed. In the g…
Environmentally-induced chaos: Extreme-mass-ratio systems of rotating black holes in astrophysical environments
Kyriakos Destounis, Pedro G. S. Fernandes
Extreme-mass-ratio inspirals, in which a stellar-mass object orbits a supermassive black hole, are prime sources of millihertz gravitational waves for upcoming space-based detector…
Lensing by black holes within astrophysical environments
Gerasimos Kouniatalis, Arthur G. Suvorov, Kyriakos Destounis
Astrophysical black holes are likely to be surrounded by various forms of matter in the form of disks or halos. While a number of studies have examined the impact of an environment…
Vortices without inflow: bound spectra in horizonless rotational analogs
H. S. Vieira, Kyriakos Destounis
Analog gravity experiments are making remarkable strides in unveiling both the classical and quantum nature of black holes. By harnessing diverse states of matter, contemporary tab…
Black hole spectroscopy: from theory to experiment
Emanuele Berti, Vitor Cardoso, Gregorio Carullo +65
The "ringdown" radiation emitted by oscillating black holes has great scientific potential. By carefully predicting the frequencies and amplitudes of black hole quasinormal modes a…
Cumulative effect of orbital resonances in extreme-mass-ratio inspirals
Edoardo Levati, Alejandro Cárdenas-Avendaño, Kyriakos Destounis +1
Orbital resonances in extreme-mass-ratio inspirals (EMRIs) have been proven to be a key feature for accurate gravitational-wave template modeling. Decades of research have led to s…
Perturbing the vortex: quasinormal and quasibound spectra of rotating acoustic geometries
H. S. Vieira, Kyriakos Destounis, Kostas D. Kokkotas
Strong-field gravity simulators are laboratory experiments that can investigate a wide range of both classical and quantum phenomena occurring in nature. In this work, we introduce…
Quasinormal modes of black holes embedded in halos of matter
Laura Pezzella, Kyriakos Destounis, Andrea Maselli +1
We investigate the (axial) quasinormal modes of black holes embedded in generic matter profiles. Our results reveal that the axial QNMs experience a redshift when the black hole is…
Superradiance of charged black holes embedded in dark matter halos
Alessandro Mollicone, Kyriakos Destounis
Astrophysical environments are ubiquitous in the Universe; from accretion disks around black holes to galactic dark matter halos, distributions of astrophysical material veil the v…
Resonant excitation of eccentricity in spherical extreme-mass-ratio inspirals
Areti Eleni, Kyriakos Destounis, Theocharis A. Apostolatos +1
Gravitational radiation reaction, has been one of the fundamental issues in general relativity. Over a span of decades, this process has been analyzed in the adiabatic limit, in or…
Ringdown stability: greybody factors as stable gravitational-wave observables
Romeo Felice Rosato, Kyriakos Destounis, Paolo Pani
The quasinormal mode spectrum of black holes plays a crucial role in the modelling of post-merger ringdown signals. However, the spectrum is extremely sensitive to small deformatio…
Pseudospectrum of de Sitter black holes
Kyriakos Destounis, Valentin Boyanov, Rodrigo Panosso Macedo
Pseudospectral analyses have broadened our understanding of ringdown waveforms from binary remnants, by providing insight into both the stability of their characteristic frequencie…
Structural aspects of the anti-de Sitter black hole pseudospectrum
Valentin Boyanov, Vitor Cardoso, Kyriakos Destounis +2
Black holes in anti-de Sitter spacetime provide an important testing ground for both gravitational and field-theoretic phenomena. In particular, the study of perturbations can be u…
Black-hole spectroscopy: quasinormal modes, ringdown stability and the pseudospectrum
Kyriakos Destounis, Francisco Duque
Black-hole spectroscopy is a powerful tool to probe the Kerr nature of astrophysical compact objects and their environment. The observation of multiple ringdown modes in gravitatio…
Spectral (in)stability of quasinormal modes and strong cosmic censorship
Aubin Courty, Kyriakos Destounis, Paolo Pani
Recent studies have shown that quasinormal modes suffer from spectral instabilities, a frailty of black holes that leads to disproportional migration of their spectra in the comple…
Slowly-rotating compact objects: the nonintegrability of Hartle-Thorne particle geodesics
Kyriakos Destounis, Kostas D. Kokkotas
X-ray astronomy provides information regarding the electromagnetic emission of active galactic nuclei and X-ray binaries. These events provide details regarding the astrophysical e…
Extreme-mass-ratio inspirals into rotating boson stars: nonintegrability, chaos, and transient resonances
Kyriakos Destounis, Federico Angeloni, Massimo Vaglio +1
General relativity predicts that black holes are described by the Kerr metric, which has integrable geodesics. This property is crucial to produce accurate waveforms from extreme-m…
Geodesics and gravitational waves in chaotic extreme-mass-ratio inspirals: the curious case of Zipoy-Voorhees black-hole mimickers
Kyriakos Destounis, Giulia Huez, Kostas D. Kokkotas
Due to the growing capacity of gravitational-wave astronomy and black-hole imaging, we will soon be able to emphatically decide if astrophysical objects lurking in galactic centers…
Analog Schwarzschild black holes of Bose-Einstein condensates in a cavity: Quasinormal modes and quasibound states
H. S. Vieira, Kyriakos Destounis, Kostas D. Kokkotas
Analog models of black holes have unequivocally proven to be extremely beneficial in providing critical information regarding black hole spectroscopy, superradiance, quantum phenom…
Gravitational waves from extreme-mass-ratio systems in astrophysical environments
Vitor Cardoso, Kyriakos Destounis, Francisco Duque +2
We establish a generic, fully-relativistic formalism to study gravitational-wave emission by extreme-mass-ratio systems in spherically-symmetric, non-vacuum black-hole spacetimes.…