Related papers: Probing planetary-mass primordial black holes with…
Primordial black holes (PBHs) have been proposed to explain at least a portion of dark matter. Observations have put strong constraints on PBHs in terms of the fraction of dark matter which they can represent, $f_{\rm PBH}$, across a wide…
General relativity predicts mass and spin growth of an inspiralling black hole due to an energy-momentum flux flowing through the black-hole horizon. The leading-order terms of this horizon flux introduce 2.5 and 3.5 post-Newtonian…
The detection of a gravitational capture of a stellar-mass compact object by a massive black hole (MBH) will allow us to test gravity in the strong regime. These sources form via two-body relaxation, by exchanging energy and angular…
Various mechanisms have been suggested for the formation of Primordial Black Holes (PBHs), and this thesis focuses on the standard mechanism based on the critical collapse of cosmological fluctuations. The underlying idea is that during…
We present a scenario in which primordial black holes (PBHs) form in a post-inflationary radiation-dominated (RD) phase and then experience significant accretion during a phase of early matter dominated (EMD). We show that PBH masses could…
We perform a consistent calculation of primordial black hole (PBH) mass spectrum and second-order induced gravitational wave (GW) background produced from primordial scalar perturbations in radiation era of the early Universe. It is shown…
The possible existence of primordial black holes in the stellar mass window has received considerable attention because their mergers may contribute to current and future gravitational-wave detections. Primordial black hole mergers,…
The direct measurement of gravitational waves is a powerful tool for surveying the population of black holes across the universe. The first gravitational wave catalog from LIGO has detected black holes as heavy as $\sim50~M_\odot$,…
Gravitational waves from precessing binary black holes exhibit new features that are absent in non-precessionary systems. All current waveform models take into account only the modulation of the signal due to precession. In this letter, we…
If primordial black holes of $\mathcal{O}(1-100) M_{\odot}$ constitute a significant portion of the dark matter in the Universe, they should be very abundant in our Galaxy. We present here a detailed analysis of the radio and X-ray emission…
A novel methodology for analysing the relation between the energy density in gravitational waves and primordial power spectra is developed. Focusing on scalar-induced gravitational radiation, this methodology is applied to a number of…
Primordial black holes (PBHs) whose masses are in $\sim[10^{-15}M_\odot,10^{-11}M_{\odot}]$ have been extensively studied as a candidate of whole dark matter (DM). One of the probes to test such a PBH-DM scenario is scalar-induced…
Gravitational waves (GWs) at ultra-low frequencies (${\lesssim 100\,\mathrm{nHz}}$) are key to understanding the assembly and evolution of astrophysical black hole (BH) binaries with masses $\sim 10^{6}-10^{9}\,M_\odot$ at low redshifts.…
Ultralight bosons can form macroscopic gravitational-atom clouds around rotating black holes via superradiance, sourcing quasi-monochromatic gravitational waves through level transitions and annihilation. Primordial black holes provide a…
The properties of the first generation of black-hole seeds trace and distinguish different models of formation of cosmic structure in the high-redshift universe. The observational challenge lies in identifying black holes in the mass range…
It was shown by (Nakamura et al. 1997), (Ioka et al. 1998), and (Sasaki et al. 2016) that primordial black holes (PBHs) binaries can form effectively at the cosmological stage of radiation dominance, and the merge of the PBHs in pairs can…
Primordial black holes in the mass range of ground-based gravitational-wave detectors can comprise a significant fraction of the dark matter. Mass and spin measurements from coalescences can be used to distinguish between an astrophysical…
It is commonly assumed that ground-based gravitational wave (GW) instruments will not be sensitive to supermassive black holes (SMBHs) because the characteristic GW frequencies are far below the ~ 10 - 1000 Hz sensitivity bands of…
A preliminary discussion is given of the prospects that gravitational-wave observations of binary inspiral of black holes could reveal or constrain quantum modifications to black hole dynamics, such as are required to preserve postulates of…
Primordial black holes (PBHs) may form in the early stages of the Universe via the collapse of large density perturbations. Depending on the formation mechanism, PBHs may exist and populate today the galactic halos and have masses in a wide…