Related papers: Black hole immunity theorem and dark matter
We address the long-standing puzzle of false vacuum decay catalyzed by black holes. Naively, small black holes with large Hawking temperatures can generate highly-boosted true vacuum bubbles in the early universe and trigger vacuum decay…
It has been observed that for black holes in certain family of Horndeski gravity theories Wald's entropy formula does not lead to the correct first law for black hole thermodynamics. For this family of Horndeski theories speeds of…
In this paper, we investigate the thermalization of Hawking radiation from primordial black holes (PBHs) in the early Universe, taking into account the interference effect on thermalization of high energy particles, known as…
Moduli fields, a natural prediction of any supergravity and superstring-inspired supersymmetry theory, may lead to a prolonged period of matter domination in the early Universe. This can be observationally viable provided the moduli decay…
It is argued that the qualitative features of black holes, regarded as quantum mechanical objects, depend both on the parameters of the hole and on the microscopic theory in which it is embedded. A thermal description is inadequate for…
Recent observational constraints indicate that primordial black holes (PBHs) with the mass scale $\sim 10^{-12}M_{\odot}$ can explain most of dark matter in the Universe. To produce this kind of PBHs, we need an enhance in the primordial…
Primordial black holes (PBHs) may be part of the dark matter. It is shown here that PBHs form more easily during cosmic phase transitions. For approximately scale-invariant primordial curvature fluctuations the PBH mass function may…
If TeV-scale gravity describes nature, black holes will be produced in particle accelerators, perhaps even with impressive rates at the Large Hadron Collider. Their decays, largely via the Hawking process, will be spectacular. Black holes…
Primordial black holes can represent all or most of the dark matter in the window $10^{17}-10^{22}\,$g. Here we present an extension of the constraints on PBHs of masses $10^{13}-10^{18}\,$g arising from the isotropic diffuse gamma ray…
We argue that primordial black-hole formation must be described by means of extreme-value theory. This is a consequence of the large values of the energy density required to initiate the collapse of black holes in the early Universe and the…
While spacetime in the vicinity outside astrophysical black holes is believed to be well understood, the event horizon and the interior remain elusive. Here, we discover a degenerate infinite spectrum of novel general relativity solutions…
The recent discovery of luminous quasars up to a redshift z=6.43 has renewed interest in the formation of black holes massive enough to power quasars. If black holes grow by Eddington-limited gas accretion with a radiative efficiency of at…
We study the matter power spectrum constraint on primordial black holes (PBH) by the dark matter (DM) emitted through Hawking radiation. We particularly focus on the scenario where PBH, with mass ranges between 1g and $10^9$g, evaporates…
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 $10^{-5}$…
The first massive astrophysical black holes likely formed at high redshifts (z>10) at the centers of low mass (~10^6 Msun) dark matter concentrations. These black holes grow by mergers and gas accretion, evolve into the population of bright…
Recent discoveries of primordial black hole (PBH) candidates by means of high cadence microlensing open the way to a physical understanding of the formation of dark matter as a chapter in the thermal history of the Universe. Two…
The amount of late decaying massive particles (e.g., gravitinos, moduli) produced in the evaporation of primordial black holes (PBHs) of mass $\Mbh\la10^9 $g is calculated. Limits imposed by big-bang nucleosynthesis on the abundance of…
The end state of Hawking evaporation of a black hole is uncertain. Some candidate quantum gravity theories, such as loop quantum gravity and asymptotic safe gravity, hint towards Planck sized remnants. If so, the Universe might be filled…
In this paper we revisit thermodynamic constraints on primordial black hole (PBH) formation in the early universe. Under the assumption that PBH mass is equal to the cosmological horizon mass, one can use the 2nd Law of Thermodynamics to…
We investigate the spontaneous creation of primordial black holes in a lower-dimensional expanding early universe. We use the no-boundary proposal to construct instanton solutions for both the background and a black hole nucleated inside…