Related papers: Primordial naked singularities
Primordial black holes are analytically and numerically discussed based on the extended McVittie spacetime solution. By assuming that dark matter and radiation are the only sources of energy accreted by the forming central object, it is…
Primordial black holes may encode the conditions of the early universe, and may even constitute a significant fraction of cosmological dark matter. Their existence has yet to be established. However, black holes with masses below…
We demonstrate that violent kinetic preheating following inflation can lead to the formation of black holes in the early Universe. In $\alpha$-attractor models with derivative inflaton couplings, nonlinear amplification of field…
Very compact objects probe extreme gravitational fields and may be the key to understand outstanding puzzles in fundamental physics. These include the nature of dark matter, the fate of spacetime singularities, or the loss of unitarity in…
Recent developments on the final state of a gravitationally collapsing massive matter cloud are summarized and reviewed here. After a brief background on the problem, we point out how the black hole and naked singularity end states arise…
We analyze here the issue of local versus the global visibility of a singularity that forms in gravitational collapse of a dust cloud, which has important implications for the weak and strong versions of the cosmic censorship hypothesis. We…
If dark matter is composed of primordial black holes, such black holes can span an enormous range of masses. A variety of observational constraints exist on massive black holes, and black holes with masses below $10^{15}\,\mathrm{g}$ are…
Primordial black holes (PBHs) form from large-amplitude initial density fluctuations and may comprise some or all of the dark matter. If PBHs have a broadly extended mass spectrum, or in mixed PBH-particle dark matter scenarios, the extreme…
We reconsider primordial black hole physics in Randall-Sundrum Type-II universes, focusing on constraints from cosmological and astrophysical observables. We pay particular attention to scenarios that allow the entirety of dark matter to be…
If the cosmological dark matter is primarily in the form of an elementary particle which has cross section and mass for self-interaction having a ratio similar to that of ordinary nuclear matter, then seed black holes (formed in stellar…
The universe is filled with various compact objects and the most attractive of them are the black holes and singularity. But it is also known that at the singularity density becomes so infinitely high that the present physics knowledge…
A model for gravitational collapse where the event horizon is a quantum critical phase transition is extended to provide an explanation for the origin of the observable universe, where the expanding universe that we observe today was…
In the context of the existence of primordial black holes (PBHs), they may compose a fraction of the dark matter of the Universe. Assuming that PBHs fill the dark content of the Milky Way Galaxy in the Galactic halo and dark disk, we…
We examine the properties of nearly extremal black holes produced by gravitational collapse. It is shown that an observer who crosses the black hole horizon at late times rapidly encounters a singularity.
Conditions under which gravity coupled to self interacting scalar field determines singularity formation are found and discussed. It is shown that, under a suitable matching with an external space, the boundary, if collapses completely, may…
Primordial black holes (PBHs) could compose the dark matter content of the Universe. We present the first simulations of cosmological structure formation with PBH dark matter that consistently include collisional few-body effects,…
We investigate primordial black hole formation in the matter-dominated phase of the Universe, where nonspherical effects in gravitational collapse play a crucial role. This is in contrast to the black hole formation in a radiation-dominated…
We devise a novel mechanism and for the first time demonstrate that the Higgs model in particle physics can drive the inflation to satisfy the cosmic microwave background observations and simultaneously enhance the curvature perturbations…
Hawking evaporation of primordial black holes (PBH) with masses ranging from $\sim 10^{-1}$ to $\sim 10^9$ g can generate the whole observed dark matter (DM) relic density. However, a second DM production mechanism, like freeze-out or…
The final mass distribution of primordial black holes is sensitive to the equation of state of the Universe at the scales accessible by the power spectrum. Motivated by the presence of phase transitions in several beyond the Standard Model…