Black hole formation in the Friedmann universe: Formulation and computation in numerical relativity
read the original abstract
We study formation of black holes in the Friedmann universe. We present a formulation of the Einstein equations under the constant mean curvature time-slicing condition. Our formalism not only gives us the analytic solution of the perturbation equations for non-linear density and metric fluctuations on superhorizon scales, but also allows us to carry out a numerical relativity simulation for black hole formation after the scale of the density fluctuations is well within the Hubble horizon scale. We perform a numerical simulation of spherically symmetric black hole formation in the radiation-dominated, spatially flat background universe for a realistic initial condition supplied from the analytic solution. It is found that the initial metric perturbation has to be non-linear (the maximum value of 3D conformal factor $\psi_0$ at $t=0$ should be larger than $\sim 1.4$) for a black hole to be formed, but the threshold amplitude for black hole formation and the final black hole mass considerably depend on the initial density (or metric) profile of the perturbation: The threshold value of $\psi_0$ at $t=0$ for formation of a black hole is smaller for a high density peak surrounded by a low density region than for that surrounded by the average density region of the flat universe. This suggests that it is necessary to take into account the spatial correlation of density fluctuations in the study of primordial black hole formation.
This paper has not been read by Pith yet.
Forward citations
Cited by 12 Pith papers
-
Gravitational Waves from Black Hole Reheating: The Scalar-Induced Component
Accounting for the minimal mass spread of primordial black holes from gravitational collapse suppresses the Poltergeist GW background to the level of generic scalar-induced signals and reopens ultra-light PBH parameter space.
-
Angular momentum of vacuum bubbles in a first-order phase transition
Computes the dimensionless spin parameter s = J/(G_N M^2) of false vacuum bubbles from density and velocity perturbations in FOPTs, yielding values from O(10^{-5}) to O(10) and a scaling relation with FOPT timescale, ...
-
Primordial Black Hole from Tensor-induced Density Fluctuation: First-order Phase Transitions and Domain Walls
Tensor perturbations from first-order phase transitions and domain wall annihilation induce curvature fluctuations at second order that form primordial black holes, allowing asteroid-mass PBHs to comprise all dark mat...
-
Isotropy, anisotropies and non-Gaussianity in the scalar-induced gravitational-wave background: diagrammatic approach for primordial non-Gaussianity up to arbitrary order
Extends diagrammatic approach for scalar-induced gravitational waves to arbitrary-order local PNG, deriving semi-analytic spectra for energy density, anisotropies, bispectrum and trispectrum up to quartic terms.
-
Curvature Perturbations from First-Order Phase Transitions: Implications to Black Holes and Gravitational Waves
Covariant analysis of curvature perturbations from first-order phase transitions reveals gauge-dependent overestimation of primordial black holes and gravitational waves in prior non-covariant calculations, leading to...
-
Primordial black hole dark matter from axion inflation
PBHs generated by axion inflation with gauge-field coupling can comprise all dark matter in the asteroidal mass range while producing a LISA-measurable stochastic GW background.
-
Purely Quadratic Non-Gaussianity from Tachyonic Instability: Primordial Black Holes and Scalar-Induced Gravitational Waves
Purely quadratic non-Gaussianity from tachyonic instability allows narrow curvature spectra to exponentially suppress primordial black hole overproduction via correlation coefficient ρ approaching -1 while retaining s...
-
Hunting Dark Matter with the Einstein Telescope
Clustered primordial black holes may constitute all dark matter and produce a flat stochastic gravitational wave background detectable by the Einstein Telescope.
-
Relic gravitational waves from primordial gravitational collapses
Sound shell collisions from Hubble-scale primordial density perturbations generate a stochastic GW background whose peak frequency and amplitude scale with the Hubble horizon and shell abundance.
-
Constraints on Primordial Black Holes
Updated compilation shows PBHs are tightly constrained across 55 orders of magnitude in mass, ruling out dominant dark matter contributions except in narrow windows, with many limits carrying observational uncertainties.
-
Primordial Black Holes as Dark Matter: Recent Developments
Primordial black holes in specific mass ranges could account for some or all dark matter while resolving structure-formation and seed problems in standard cosmology.
-
Scalar induced gravitational waves review
A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.