Related papers: The interference and gravitational redshift effect…
In the dense regions of star clusters, close encounters with black holes (BHs) can occur giving rise to a new class of gravitational-wave (GW) signals. Binary-single encounters between three BHs are expected to dominate the rate of signals…
Wave packets propagating in inhomogeneous media experience a coupling between internal and external degrees of freedom and, as a consequence, follow spin-dependent trajectories. These phenomena, well known in optics and condensed matter…
A black hole binary approaching merger undergoes changes in its inspiral rate as energy and angular momentum are lost from the orbits into the horizons. This effect strengthens as the black holes come closer. We use numerical relativity…
The localization of stellar-mass binary black hole mergers using gravitational waves is critical in understanding the properties of the binaries' host galaxies, observing possible electromagnetic emission from the mergers, or using them as…
We investigate the impact of dark fluid accretion on gravitational waveforms emitted by a compact binary system consisting of a supermassive black hole and a stellar-mass black hole. Using a Lagrangian framework with 1~PN and 2.5~PN…
Light bosons can form a gravitational atom (GA) around a spinning black hole through the superradiance process. Considering the black hole to be part of a binary system, the tidal potential of the companion periodically perturbs the GA such…
We discuss the conditions under which plane electromagnetic and gravitational waves can be amplified by a rotating black hole due to superradiant scattering. We show, in particular, that amplification can occur for low-frequency waves with…
We investigate how GWs pass through the spacetime of a Schwarzschild black hole using time-domain numerical simulations. Our work is based on the perturbed 3+1 Einstein's equations up to the linear order. We show explicitly that our…
Supermassive black holes are investigated as possible sources for low-frequency bursts of gravity waves. The event rate for `known' supermassive black holes at intermediate and high redshifts, inferred from the quasar luminosity function,…
Recent breakthroughs in the field of numerical relativity have led to dramatic progress in understanding the predictions of General Relativity for the dynamical interactions of two black holes in the regime of very strong gravitational…
A precise electromagnetic measurement of the sky coordinates and redshift of a coalescing black hole binary holds the key for using its gravitational wave (GW) signal to constrain cosmological parameters and to test general relativity. Here…
Now that LIGO has revealed the existence of a large number of binary black holes, identifying their origin becomes an important challenge. They might originate in more isolated regions of the galaxy or alternatively they might reside in…
In the theories with extra dimensions, gravitational waves can leak into extra dimensions, resulting in a reduction in the amplitude of the observed gravitational waves. Such an effect modifies the standard luminosity distance of…
Gravitational waves in general relativity are non-dispersive, yet a host of modified theories predict dispersion effects during propagation. In this work, we consider the impact of dispersion effects on gravitational-wave bursts from highly…
Gravitational waves from inspiraling compact binaries are known to be an excellent absolute distance indicator, yet it is unclear whether electromagnetic counterparts of these events are securely identified for measuring their redshifts,…
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…
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…
The improvements in the sensitivity of the gravitational wave (GW) network enable the detection of several large redshift GW sources by third-generation GW detectors. These advancements provide an independent method to probe the large-scale…
We compute and analyze the gravitational waveform emitted to future null infinity by a system of two black holes in the large mass ratio limit. We consider the transition from the quasi-adiabatic inspiral to plunge, merger, and ringdown.…
We study eccentric equatorial orbits of a stellar-mass black hole around an intermediate-mass slowly rotating Kerr black hole in the presence of gravitational radiation and a dark matter halo. The stellar-mass companion will inspiral…