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.
Formation of Black Holes from Collapsed Cosmic String Loops
5 Pith papers cite this work. Polarity classification is still indexing.
abstract
The fraction of cosmic string loops which collapse to form black holes is estimated using a set of realistic loops generated by loop fragmentation. The smallest radius sphere into which each cosmic string loop may fit is obtained by monitoring the loop through one period of oscillation. For a loop with invariant length $L$ which contracts to within a sphere of radius $R$, the minimum mass-per-unit length $\mu_{\rm min}$ necessary for the cosmic string loop to form a black hole according to the hoop conjecture is $\mu_{\rm min} = R /(2 G L)$. Analyzing $25,576$ loops, we obtain the empirical estimate $f_{\rm BH} = 10^{4.9\pm 0.2} (G\mu)^{4.1 \pm 0.1}$ for the fraction of cosmic string loops which collapse to form black holes as a function of the mass-per-unit length $\mu$ in the range $10^{-3} \lesssim G\mu \lesssim 3 \times 10^{-2}$. We use this power law to extrapolate to $G\mu \sim 10^{-6}$, obtaining the fraction $f_{\rm BH}$ of physically interesting cosmic string loops which collapse to form black holes within one oscillation period of formation. Comparing this fraction with the observational bounds on a population of evaporating black holes, we obtain the limit $G\mu \le 3.1 (\pm 0.7) \times 10^{-6}$ on the cosmic string mass-per-unit-length. This limit is consistent with all other observational bounds.
citation-role summary
citation-polarity summary
verdicts
UNVERDICTED 5representative citing papers
Scaling monopoles generate PBHs via stochastic overdensities and GWs with correlated spectra, potentially with magnetically charged PBHs as a signature if the scaling ends via gauge boson mass.
3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.
PBH-triggered SN Ia models across metallicities match some observed light curves and remnants, constrain the explosion channel fraction via chemical evolution modeling, and indicate PBHs as a potentially major early-universe SN Ia source.
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.
citing papers explorer
-
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.
-
PBHs and GWs from Scaling Monopoles
Scaling monopoles generate PBHs via stochastic overdensities and GWs with correlated spectra, potentially with magnetically charged PBHs as a signature if the scaling ends via gauge boson mass.
-
Numerical simulations of density perturbation and gravitational wave production from cosmological first-order phase transition
3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.
-
Primordial Black Hole Triggered Type Ia Supernovae II: Comparison with Supernova Remnants and Galactic Chemical Evolution
PBH-triggered SN Ia models across metallicities match some observed light curves and remnants, constrain the explosion channel fraction via chemical evolution modeling, and indicate PBHs as a potentially major early-universe SN Ia source.
-
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.