Simulations of Ellipsoidal Primordial Black Hole Formation

Abstract

We perform $3+1$ relativistic numerical simulations to study primordial black hole (PBH) formation from the collapse of adiabatic super-horizon non-spherical perturbations generated from curvature fluctuations obeying random Gaussian statistics with a monochromatic power spectrum. The matter field is assumed to be a perfect fluid of an equation of state $w:=P/\rho =const.$ with $P$ and $\rho$ being the pressure and the energy density, respectively. The initial spatial profile of the curvature perturbation is modeled with the amplitude $\mu$ and non-spherical parameters $e$ (ellipticity) and $p$ (prolateness) according to peak theory. We focus on the dynamics and the threshold for PBH formation in terms of the non-spherical parameters $e$ and $p$. We find that the critical values ($e_c,p_c$) with a fixed value of $\mu$ closely follow a superellipse curve. With $p=0$, for the range of amplitudes considered, we find that the critical ellipticity for non-spherical collapse follows a decaying power law as a function of $(\mu -{\mu }_{\mathrm{c},\mathrm{sp}})$ with ${\mu }_{\mathrm{c},\mathrm{sp}}$ being the threshold for the spherical case. Our results also indicate that, for both cases of $w=1/3$ and $w=1/10$, small deviations from sphericity can avoid collapsing to a black hole when the amplitude is near its critical threshold. Finally we discuss the significance of the ellipticity on the rate of the PBH production.

37 pages, 24 figures. v3: appendix added. Published in Phys. Rev. D

References in corpus (30)

• GWTC-3: Compact Binary Coalescences Observed by LIGO and Virgo During the Second Part of the Third Observing Run
• The NANOGrav 15-year Data Set: Search for Signals from New Physics
• Primordial Black Holes as Dark Matter: Recent Developments
• The merger rate of primordial-black-hole binaries
• Simulating coalescing compact binaries by a new code SACRA
• Observational Evidence for Primordial Black Holes: A Positivist Perspective
• From inflation to black hole mergers and back again: Gravitational-wave data-driven constraints on inflationary scenarios with a first-principle model of primordial black holes across the QCD epoch
• Primordial black holes from inflaton and spectator field perturbations in a matter-dominated era
• Primordial Black Hole Dark Matter and the LIGO/Virgo observations
• Probing the equation of state of the early Universe with pulsar timing arrays
• PBH formation from spherically symmetric hydrodynamical perturbations: a review
• Simulations of PBH formation at the QCD epoch and comparison with the GWTC-3 catalog
• Induced Gravitational Wave interpretation of PTA data: a complete study for general equation of state
• Simultaneously probing the sound speed and equation of state of the early Universe with pulsar timing arrays
• Black Hole Universe with $\Lambda$
• Primordial black hole formation with full numerical relativity
• Effects of the shape of curvature peaks on the size of primordial black holes
• Realisation of the ultra-slow roll phase in Galileon inflation and PBH overproduction
• The QCD phase transition behind a PBH origin of LIGO/Virgo events?
• A new mechanism for primordial black hole formation during reheating
• Primordial black hole formation from massless scalar isocurvature
• Numerical simulation of type II primordial black hole formation
• Threshold of Primordial Black Hole Formation against Velocity Dispersion in Matter-Dominated Era
• Primordial Black Hole Formation during a Strongly Coupled Crossover
• Primordial Black Hole formation from overlapping cosmological fluctuations
• Critical gravitational collapse with angular momentum
• Complex Scalar Field Reheating and Primordial Black Hole production
• Twist-free axisymmetric critical collapse of a complex scalar field
• Primordial Black Holes and Induced Gravitational Waves from a Smooth Crossover beyond Standard Model
• Non-spherical effects on the mass function of Primordial Black Holes

Cited by in corpus (6)

• Non-spherical effects on the mass function of Primordial Black Holes
• Threshold for PBH formation in the type-II region and its analytical estimation
• Sound waves from primordial black hole formations
• Inflationary relics from an Ultra-Slow-Roll plateau
• COSMOS: A numerical relativity code specialized for PBH formation
• Effect of stochastic kicks on primordial black hole abundance and mass via the compaction function