Spin of primordial black holes
Mehrdad Mirbabayi, Andrei Gruzinov, Jorge Noreña
Abstract
Primordial black holes, formed from rare peaks in the primordial fluctuations $\zeta$, are non-rotating at zeroth order in $\zeta_{\rm rms}$. We show that the spin also vanishes at first order in $\zeta_{\rm rms}$, suggesting the dimensionless spin parameter $a_{\rm rms} \sim \zeta_{\rm rms}^2$. We identify one quadratic contribution to the spin by calculating (and extrapolating to the formation time) the torque on a black hole due to ambient acoustic waves. For a reasonable density of primordial black holes this implies a percent level spin parameter.
Topics & Concepts
PhysicsPrimordial black holeSpin (aerodynamics)Black hole (networking)Hawking radiationAstrophysicsOrder (exchange)Quantum electrodynamicsSpin-upSpin-flipQuadratic equationCosmologyMicro black holeSonic black holePrimordial fluctuationsCosmological perturbation theoryInflation (cosmology)Binary black holePlanckFirst orderBlack Holes and Theoretical PhysicsQuantum Electrodynamics and Casimir EffectQuantum Chromodynamics and Particle Interactions