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Primordial Black Holes in an Accelerating Universe

David Polarski
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Abstract

General expressions are given for the generation of Primordial Black Holes (PBH) in a universe with a presently accelerated expansion due to a(n effective) cosmological constant. We give expressions both for a powerlaw scalefree primordial spectrum and for spectra which are not of that type. Specializing to the case of a pure cosmological constant $Λ$ and assuming flatness, we show that a comological constant with $Ω_{Λ,0}=0.7$ will decrease the mass variance at the PBH formation time by about 15% compared with a critical density universe.

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David Polarski. 2002-01-22. Primordial Black Holes in an Accelerating Universe. https://doi.org/10.1016/s0370-2693(02)01200-5

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