Related papers: Early black-hole seeds in the first billion years
In this paper we derive the mass function of seed black holes that result from the central mass concentrated via disc accretion in collapsed haloes at redshift $z\approx 15$. Using standard arguments including stability, we show that these…
The origin of the seeds which develop into the observed super-massive black holes at high redshifts may be hard to interpret in the context of the standard $\Lambda CDM$ of early universe cosmology based on Gaussian primordial…
High redshift observations of 10$^9$ M$_\odot$ supermassive black holes (SMBHs) at $z \sim7$ and `Little Red Dots' that may host overmassive black holes at $z>4$ suggests the existence of so-called heavy seeds (>1000 M$_\odot$) in the early…
Determining the mechanisms that formed and grew the first supermassive black holes is one of top priorities in extragalactic astrophysics. Observational clues can be inferred from the demographics of massive black holes (in the ten thousand…
Evidence for high-redshift supermassive black holes challenges standard scenarios for how such objects form in the early universe. Here, we entertain the possibility that a fraction of the cosmological dark matter could be ultra-strongly…
The physical processes that led to the formation of billion solar mass black holes within the first 700 million years of cosmic time remain a puzzle. Several theoretical scenarios have been proposed to seed and rapidly grow black holes, but…
The origin of supermassive black holes is an open question that has been explored considering gas- and collision-based formation channels to explain the high number of quasars observed in the early Universe. According to numerical…
The existence of quasars at redshift z > 5 indicates that supermassive black holes were present since the very early times. If they grew by accretion, the seeds of mass ~ 10^5 Msun must have formed at z ~ 9. These seed black holes may…
The origin of supermassive black holes (SMBHs) is a key open question for contemporary astrophysics and cosmology. Here we review the features of a cosmological model of SMBH formation from Pop III.1 seeds, i.e., remnants of metal-free…
The emergence of the first black holes during the first billion years of cosmic history marks a key event in cosmology. Their formation is part of the overall process of ending the cosmic dark ages, when the first stars appeared in low-mass…
Primordial black holes in the asteroid-mass window ($\sim 10^{-16}$ to $10^{-11} \rm M_{\odot}$), which might constitute all the dark matter, can be captured by stars when they traverse them at low enough velocity. After being placed on a…
The most massive black holes observed in the Universe weigh up to $\sim 10^{10} \, \mathrm{M_{\odot}}$, nearly independent of redshift. Reaching these final masses likely required copious accretion and several major mergers. Employing a…
We study the gravitational wave background produced from the formation and assembly of supermassive black holes within the cosmological paradigm of hierarchical structure formation. In particular, we focus on a supermassive black hole…
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…
Recent studies show that light seeds of black holes, which grow into massive black holes (MBHs) over time, often struggle to remain at the centers of their birthplaces in high-redshift galaxies, limiting their ability to accrete gas and…
Black holes with hundreds to thousands of solar masses are more massive than can be formed from a single star in the current universe, yet the best candidates for these objects are not located in gas-rich environments where gradual…
Primordial black holes can be produced by density fluctuations generated from delayed vacuum decays of first-order phase transition. The primordial black holes generated at the electroweak phase transition have masses of about $10^{-5}$…
We investigate the evolution of the primordial gas surrounding the first massive black holes formed by the collapse of Population III stars at redshifts z > 20. Carrying out three-dimensional hydrodynamical simulations using GADGET, we…
We discuss the production of primordial black holes in an early matter dominated era, which typically takes place in string inspired early universe cosmological models. In particular, we consider a pre-big bang scenario (extending previous…
In this paper a simple (i.e. free of fine-tuning, etc.) new mechanism for primordial black hole formation based on the collapse of large antimatter systems in the early Universe is introduced. A peculiarity of this process is that, compared…