Related papers: Black hole formation in relativistic Oscillaton co…
The gyraton model describes a gravitational field of an object moving with the velocity of light which has finite energy and spin distributed during some finite time interval $L$. A gyraton may be considered as a classical toy model for a…
We study the production of primordial black holes (PBHs) during the preheating stage that follows a chaotic inflationary phase. The scalar fields present in the process are evolved numerically using a modified version of the HLATTICE code.…
Massive primordial halos exposed to moderate UV backgrounds are the potential birthplaces of supermassive black holes. In such a halo, an initially isothermal collapse will occur, leading to high accretion rates of…
We argue that a simple modification of the TeV scale quantum gravity scenario allows production of semiclassical black holes in particle collisions at the LHC. The key idea is that in models with large extra dimensions the strength of…
Abstract Black hole collision produce gravitational radiation which is generally thought in a quantum limit to be gravitons. The stretched horizon of a black hole contains quantum information, or a form of quantum hair, which in a…
We consider the head-on collision of equal-mass neutron stars boosted towards each other and we study the behavior of such systems near the threshold of black-hole formation. In particular, we confirm the previous findings by [1] that a…
Supersymmetric extensions of the standard model generically predict that in the early universe a scalar condensate can form and fragment into Q-balls before decaying. If the Q-balls dominate the energy density for some period of time, the…
Supermassive black holes (SMBHs) are common in local galactic nuclei, and SMBHs as massive as several billion solar masses already exist at redshift z=6. These earliest SMBHs may grow by the combination of radiation-pressure-limited…
We investigate new paths to black hole formation by considering the general relativistic evolution of a differentially rotating polytrope with toroidal shape. We find that this polytrope is unstable to nonaxisymmetric modes, which leads to…
Within the framework that primordial black holes are formed by the direct gravitational collapse of large primordial density perturbations in the radiation dominated stage, we derive the threshold of the density contrast for the formation…
Primordial Black Holes (PBHs) might have formed in the early Universe as a consequence of the collapse of density fluctuations with an amplitude above a critical value $\delta_{c}$: the formation threshold. Although for a…
Production of black holes has been discussed in a variety of extensions of the Standard Model, and related bounds have been established from data taken at the Large Hadron Collider. We show that, if the Higgs particle has a fully…
We investigate axisymmetric black hole~(BH) formation and its gravitational wave (GW) and neutrino signals with self-consistent core-collapse supernova simulations of a non-rotating $40~M_\odot$ progenitor star using the isotropic diffusion…
We study the interplay between galaxy evolution and central black-hole (BH) growth using the {NewHorizon} cosmological simulation. BH growth is slow when the dark-matter halo is below a golden mass of $M_{\rm v} \sim 10^{12} \rm M_\odot$,…
The polytropic equation of state of an atomic hydrogen gas is examined for primordial halos with baryonic masses of M_h~10^7-10^9 Mo. For roughly isothermal collapse around 10^4 K, we find that line trapping of Lyman alpha (HI and HeII)…
We describe a mechanism by which supermassive black holes can form directly in the nuclei of protogalaxies, without the need for seed black holes left over from early star formation. Self-gravitating gas in dark matter halos can lose…
We predict the existence and observational signatures of a new class of objects that assembled early, during the first billion years of cosmic time: Obese Black-hole Galaxies (OBGs). OBGs are objects in which the mass of the central black…
The high redshifts of the most distant known quasars, and the best estimates of their black hole masses, require that supermassive black holes (SMBHs) must have formed very early in history. Several mechanisms for creating and growing these…
We revisit the question of how generic is the formation of primordial black holes via self-resonant growth of inflaton fluctuations in the post-inflationary, preheating phase. Using analytical and lattice calculations, we find that…
The first LIGO-Virgo detections have confirmed the existence of massive black holes (BHs), with mass $30-40$ M$_\odot$. Such BHs might originate from massive metal-poor stars ($Z<0.3$ Z$_\odot$) or from gravitational instabilities in the…