Related papers: Microscopic primordial black holes and extra dimen…
We study how the constraints on the primordial black hole density arising from the extragalactic photon background are modified in the scenario that there exist extra large spatial dimensions. We find that though the overall magnitude of…
Several processes in the early universe might lead to the formation of primordial black holes with different masses. These black holes would interact with the cosmic plasma through accretion and emission processes. Such interactions might…
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…
We study the evolution of primordial black holes (PBHs) formed in the early universe in the presence of a surrounding thermal bath. By incorporating the effects of thermal absorption, we show that PBHs can undergo significant mass growth,…
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…
Building on the insight that primordial black holes can arise from the formation and subsequent gravitational collapse of bound states of stable supermassive elementary particles during the early radiation era, we offer a comprehensive…
The hypothesis of existence of primordial black holes with large masses (\geq 10^6 M\odot), formed at the earliest stages of the Universe evolution, is considered in the paper. The possibility does not contradict some theories, see e.g.…
We discuss the model of the primordial black holes formation at the reheating stage. These small massive black holes appear due to specific properties of the compact extra dimensions. The latter gives rise the low energy model containing…
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…
We study the coupled cosmological evolution of primordial black holes (PBHs) and radiation in the Arkani-Hamed-Dimopoulos-Dvali (ADD) framework with $n$ large extra dimensions and a fundamental gravity scale $M_\star$ at the TeV scale. For…
With detections of quasars powered by increasingly massive black holes (BHs) at increasingly early times in cosmic history over the past decade, there has been correspondingly rapid progress made on the theory of early BH formation and…
Theories of large extra dimensions (LEDs) such as the Arkani-Hamed, Dimopoulos & Dvali scenario predict a "true" Planck scale $M_\star$ near the TeV scale, while the observed $M_{pl}$ is due to the geometric effect of compact extra…
We present a novel model-independent generic mechanism for primordial black hole formation within the context of non-singular matter bouncing cosmology. In particular, considering a short duration transition from the matter contracting…
We discuss the possibility of forming primordial black holes during a first-order phase transition in the early Universe. As is well known, such a phase transition proceeds through the formation of true-vacuum bubbles in a Universe that is…
We discuss the various ways in which primordial black holes may have formed in the early Universe and how the effects of such black holes can be used to place constraints on cosmological models. We show that such constraints may be severely…
The discovery of high redshift quasars represents a challenge to the origin of supermassive black holes. Here, two evolutionary scenarios are considered. The first one concerns massive black holes in the local universe, which in a large…
Many cosmological phenomena lead to the production of primordial black holes in the early Universe. These phenomena often create a population of black holes with extended mass and spin distributions. As these black holes evaporate via…
Small black holes should have formed in the early Universe if the density contrast was high enough. This article aims at giving a - biased and partial - short overview of the latest breakthroughs in this field. It first deals with tentative…
Primordial black holes may have formed in the radiative era of the early Universe from the collapse of large enough amplitude perturbations of the metric. These correspond to non linear energy density perturbations characterized by an…
Primordial black holes may form in the early Universe, for example from the collapse of large amplitude density perturbations predicted in some inflationary models. Light black holes undergo Hawking evaporation, the energy injection from…