Related papers: Black Holes in the Early Universe
Quasars are the earliest objects known to exist. We examine their origin in the context of popular models for structure formation in the universe. We show that seeds for quasar black holes could have originated from the initial cosmological…
In this small review we present the actual state the knowledge about weighting black holes. Black holes can be found in stellar binary systems in our Galaxy and in other nearby galaxies, in globular clusters, which we can see in our and…
Understanding how supermassive black holes (SMBHs) form in the early universe is one of the most challenging problems in astrophysics. Their high abundance in the first billion years, as observed by the James Webb Space Telescope, hints…
We investigate the formation of the first massive black holes in high redshift galaxies, with the goal of providing insights to which galaxies do or do not host massive black holes. We adopt a novel approach to forming seed black holes in…
Supermassive black holes with billion solar masses are in place already within the first Gyr, however, their origin and growth in such a short lapse of time is extremely challenging to understand. Here, we discuss the formation paths of…
Supermassive black holes are nowadays believed to reside in most local galaxies. Observations have revealed us vast information on the population of local and distant black holes, but the detailed physical properties of these dark massive…
In the local universe, black hole masses have been inferred from the observed increase in the velocities of stars at the centres of their host galaxies. So far, masses of supermassive black holes in the early universe have only been…
The statistics of black holes and their masses strongly suggests that their mass distribution has a cutoff towards lower masses near $3 \times 10^{6}$ M$_{\odot}$. This is consistent with a classical formation mechanism from the…
The early Universe was composed almost entirely of hydrogen and helium, with only trace amounts of heavy elements. It was only after the first generation of star formation that the Universe became sufficiently polluted to produce a second…
The growth of the most massive black holes in the early universe, consistent with the detection of highly luminous quasars at $z> 6$ implies sustained, critical accretion of material to grow and power them. Given a black hole seed scenario,…
A new model for the formation of active galaxies is described. A key feature of this model is the idea that the birth of black holes in the centers of supergiant galaxies is strongly influenced by the large-scale distribution of matter in…
The recent discovery of a large number of massive black holes within the first two billion years after the Big Bang, as well as their peculiar properties, have been largely unexpected based on the extrapolation of the properties of luminous…
Binary black holes occupy a special place in our quest for understanding the evolution of galaxies along cosmic history. If massive black holes grow at the center of (pre-)galactic structures that experience a sequence of merger episodes,…
I recall how the discovery of quasars occurred more than forty years ago, and the strong debates marking out their story. It led to the discovery of Massive Black Holes, which are now known to be present in almost all galaxies, and it…
It is argued that the bulk of black holes (BH) in the universe are primordial (PBH). This assertion is strongly supported by the recent astronomical observations, which allow to conclude that supermassive BHs with $M= (10^6 - 10^9) M_\odot$…
We describe a mechanism of the primordial black holes formation that can explain the existence of a population of supermassive black holes in galactic bulges. The mechanism is based on the formation of black holes from closed domain walls.…
A significant population of quasars have been found to exist within the first Gyr of cosmic time. Most of them have high black hole (BH) masses ($M_{\rm BH} \sim 10^{8-10} M_{\odot}$) with an elevated BH-to-stellar mass ratio compared to…
Astronomers have discovered two populations of black holes: (i) stellar-mass black holes with masses in the range 5 to 30 solar masses, millions of which are present in each galaxy in the universe, and (ii) supermassive black holes with…
More than 300 supermassive black holes have been detected at redshifts larger than 6, and they are abundant in the centers of local galaxies. Their formation mechanisms, however, are still rather unconstrained. A possible origin of these…
Supermassive black holes are now realized to exist in the centers of most galaxies. The recent discoveries of luminous quasars at redshifts higher than 6 require that these black holes were assembled already when the Universe was less than…