Related papers: Gravitational Wave Signatures Induced by Dark Flui…
Modeling the late inspiral and merger of supermassive black holes is central to understanding accretion processes and the conditions under which electromagnetic emission accompanies gravitational waves. We use fully general relativistic,…
This paper reports results from numerical simulations of the gravitational radiation emitted from non--rotating compact objects(both neutron stars and Schwarzschild black holes) as a result of the accretion of matter. A hybrid procedure is…
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…
Binary black-hole systems with spins aligned or anti-aligned to the orbital angular momentum provide the natural ground to start detailed studies of the influence of strong-field spin effects on gravitational wave observations of coalescing…
Scalar fields of masses between $10^{-21}\rm{eV}/c^2$ and $10^{-11} \rm{eV}/c^2$ can exhibit enhanced gravitational interactions with black holes, and form scalar clouds around them. Such a cloud modifies the dynamics of a coalescing…
We propose a new scenario for the evolution of a binary of primordial black holes (PBHs). We consider a dynamical friction by ambient dark matter, scattering of dark matter particles with a highly eccentric orbit besides the standard…
Several models of physics beyond the Standard Model predict the existence of new ultralight bosons. This thesis investigates a way to discover such particles through observations of gravitational waves from binary black holes. This is…
We consider the gas dynamics in an accreting binary system of degenerate stars within the framework of the Newtonian approximation. In such a system, the accretion stream can impact the surface of a white dwarf (WD) or neutron star (NS) as…
Dark matter halos can develop a density spike, e.g., around a galactic supermassive black hole, with the profile $\rho \propto r^{-\gamma_{\rm sp}}$ determined both by the galaxy's formation history and the microphysics of dark matter. We…
Spinning black holes could produce ultralight particles via the superradiance instability. These particles form a dense cloud around the host black hole, introducing new opportunities for the detection of ultralight new physics. When the…
Gravitational waves emitted by black hole binary inspiral and mergers enable unprecedented strong-field tests of gravity, requiring accurate theoretical modelling of the expected signals in extensions of General Relativity. In this paper we…
Massive black hole binaries (MBHBs) form as a consequence of galaxy mergers. However, it is still unclear whether they typically merge within a Hubble time, and how accretion may affect their evolution. These questions will be addressed by…
We present a theoretical study of the gravitational wave (GW) driven inspirals of accreting black hole binaries with mass $M = 10^7 M_\odot$ and mass ratios between $10^{-3}$ and $10^{-1}$. Our results are based on analytic estimates, and…
We extend our research on the energy flux and waveform characteristics of gravitational waves generated by merging nonspinning binary black holes through self-consistent effective one-body theory \cite{L2023} to include binary systems with…
Gravitational waves emitted by distorted black holes, such as those arising from the coalescence of binary black holes, or a falling compact star into a supermassive black hole, carry not only information about the corresponding spacetime…
We study the gravitational wave (GW) emission of sources perturbed by periodic dynamical forces which do not cause secular evolution in the orbital elements. We construct a corresponding post-Newtonian waveform model and provide estimates…
The particles of a dark matter due to gravitational interaction deviate from straight trajectories in the vicinity of a massive body. This causes their density to become inhomogeneous. The developed density contrast causes a gravitation…
The detection of gravitational waves (GWs) has led to a deeper understanding of binaries of ordinary astrophysical objects, including neutron stars and black holes. In this work, we point out that binary systems may also exist in a dark…
As binary systems move inside galaxies, they interact with the dark matter halo. This interaction leads to the accretion of dark matter particles inside binary components. The accretion of dark matter particles increases the mass of the…
Is the graviton massless? This problem was addressed in the literature at a phenomenological level, using modified dispersion relations for gravitational waves, in linearized calculations around flat space. Here, we perform a detailed…