相关论文: Black hole immunity theorem and dark matter
In this paper, we explore the possibility of accreting primordial black holes as the source of heating for the collapsing gas in the context of the direct collapse black hole scenario for the formation of super-massive black holes (SMBHs)…
Holographic space-time, a theory of quantum gravity that generalizes string theory and quantum field theory, predicts black holes in the early matter-dominated era of its models of inflation. Before these black holes can decay, there is a…
It has recently become fashionable to regard black holes as elementary particles. By taking this suggestion seriously it is possible to cobble together an elementary particle physics based estimate for the decay rate $(\hbox{black hole})_i…
Primordial black holes (PBHs) have been explored as potential dark matter candidates, with various astrophysical observations placing upper limits on the fraction $f_\mathrm{PBH}$ of dark matter in the form of PBHs. However, a largely…
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.…
In the current standard viewpoint small black holes are believed to emit radiation as black bodies at the Hawking temperature, at least until they reach Planck size, after which their fate is open to conjecture. A cogent argument against…
We investigate Primoridal Black Hole (PBH) formation by which we mean black holes produced in the early universe during radiation domination. After discussing the range of PBH mass permitted in the original mechanism of Carr and Hawking,…
We study the possible correspondence between 5-dimensional primordial black holes and massive 5-dimensional KK gravitons as dark matter candidate within the recently proposed dark dimension scenario that addresses the cosmological hierarchy…
The Reheating process at the end of inflation is often modeled by an oscillating scalar field which shows a background dust-like behaviour, prompting the analysis of gravitational collapse and black hole formation in this era to be…
In light of recent evidence suggesting a nonzero present-day cosmological constant, Adams, Mbonye, & Laughlin (1999) have considered the evolution of black holes in the presence of vacuum energy. Using the assumption that Lambda remains…
We comment on recent claims that recoil in the final stages of Hawking evaporation gives black hole remnants large velocities, rendering them inviable as a dark matter candidate. We point out that due to cosmic expansion, such large…
The non-observation of Hawking radiation from primordial black holes of $10^{16}$g sets a conservative strong bound on their cosmological abundance. We revisit this bound and show how it can be improved (both in mass reach and strength) by…
Formation of significant number of primordial black holes (PBHs) is realized if and only if primordial density fluctuations have a large amplitude, which means that tensor perturbations generated from these scalar perturbations as a second…
Black holes are expected to evaporate through the process of Hawking radiation. This process is expected to cause the uncertainty in a black hole's position to grow to $\sim M^2/M_{Pl}^3$ over the course of it's lifetime, even as its…
We reconsider the possibility that the observed baryon asymmetry was generated by the evaporation of primordial black holes that dominated the early universe. We present a simple derivation showing that the baryon asymmetry is insensitive…
We show that resonant processes during multi-field inflation can generate a large curvature perturbation on small scales. This perturbation naturally leads to the formation of primordial black holes that may constitute dark matter, as well…
There is growing notion that black holes may not contain curvature singularities (and that indeed nature in general may abhor such spacetime defects). This notion could have implications on our understanding of the evolution of primordial…
It has been widely believed that the Hawking temperature for a black hole is $uniquely$ determined by its metric and $positive$. But, I find that this does ``not'' seem to be true in the recently discovered black holes which include the…
In this work, we study the evolution of Primordial Black Holes within the context of Loop Quantum Gravity. First we calculate the scale factor and energy density of the universe for different cosmic era and then taking these as inputs we…
Primordial black holes (PBHs) in the mass range $10^{17} - 10^{23}~{\rm gm}$ are considered as possible dark matter candidates as they are not subject to big-bang nucleosynthesis constraints and behave like cold dark matter. If PBHs are…