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arXiv · hep-ph/0503267

Primordial Black Holes, Hawking Radiation and the Early Universe

Paul H. Frampton·Thomas W. Kephart
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Abstract

The 511 keV gamma emission from the galactic core may originate from a high concentration ($\sim 10^{22}$) of primordial black holes (PBHs) in the core each of whose Hawking radiation includes $\sim 10^{21}$ positrons per second. The PBHs we consider are taken as near the lightest with longevity greater than the age of the universe (mass $\sim 10^{12}$ kg; Schwarzschild radius $\sim 1$ fm). These PBHs contribute only a small fraction of cold dark matter, $Ω_{PBH} \sim 10^{-8}$. This speculative hypothesis, if confirmed implies the simultaneous discovery of Hawking radiation and an early universe phase transition.

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Paul H. Frampton, Thomas W. Kephart. 2005-03-27. Primordial Black Holes, Hawking Radiation and the Early Universe. https://doi.org/10.1142/s0217732305017688

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