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arXiv · 1904.03781

Implications of Symmetry and Pressure in Friedmann Cosmology. II. Stellar Remnant Black Hole Mass Function

Abstract

We consider some observational consequences of replacing all black holes (BHs) with a class of non-singular solutions that mimic BHs but with Dark Energy (DE) interiors; GEneric Objects of Dark Energy (GEODEs). We focus on the BH mass function and chirp-mass redshift distribution of mergers visible to gravitational wave observatories. We incorporate the GEODE blueshift into an initially Salpeter stellar remnant distribution, and model the binary population by evolving synthesized binary remnant distributions, published before LIGO's first measurements. We find that a GEODE produced between $20 \lesssim z \lesssim 40$, and observed at $z \sim 7$, will have its initial mass amplified by $\sim 20-140\times$. This can relieve tension between accretion-only growth models and the inferred masses of BHs in quasars at $z \gtrsim 6$. Moreover, we find that merger rates of GEODE binaries increase by a factor of $\sim 2\times$ relative to classical BHs. The resulting GEODE mass function is consistent with the most recent LIGO constraints at $< 0.5σ$. In contrast, a Salpeter stellar distribution that evolves into classical remnants is in tension at $\gtrsim 2σ$. This agreement occurs without low-metallicity regions, abnormally massive progenitor stars, novel formation channels, or primordial object formation at extreme rates. In particular, we find that solar metallicity progenitors, which produce $1.1-1.8\mathrm{M}_\odot$ remnants, overlap with many LIGO observations when evolved as GEODEs.

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Kevin Croker, Kurtis Nishimura, Duncan Farrah. 2020-09-10. Implications of Symmetry and Pressure in Friedmann Cosmology. II. Stellar Remnant Black Hole Mass Function. https://doi.org/10.3847/1538-4357%2Fab5aff

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