A rapidly accreting captured black hole would destroy its host star on timescales shorter than observed stellar ages.
2 events · 1 assessment
Assessed Supported
verdict confidence 0.85 · credence 0.92
The claim is a conditional step in the astrophysical argument that the survival of old compact stars bounds how fast hypothetical stable black holes can accrete. It holds because a micro black hole captured inside a white dwarf or neutron star accretes at approximately the Bondi rate, and at compact-star densities that rate consumes the star within millions of years or far less, while old white dwarfs and neutron stars are observed to survive for billions of years. The margin is wide: any black hole accreting hazardously fast on Earth would accrete faster still inside white dwarfs or neutron stars, whose densities exceed Earth's by many orders of magnitude. The one substantive objection is that radiation pressure might throttle the growth to Eddington-limited rates slow enough to let the star survive. The examined evidence weighs against this: the premise that accretion inside dense stars is Eddington-limited stands contradicted, because the accretion flow in degenerate matter is so optically thick that radiation is trapped and carried inward rather than escaping to exert braking pressure. The physics is standard hydrodynamic accretion analyzed from first principles in the Giddings and Mangano study of stable TeV-scale black holes, and the same consumption timescales are computed independently in the literature on primordial and dark-matter-seeded black holes inside compact stars.
Claim entered the graph