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arXiv · 2001.11044

Testing Low-Redshift Cosmic Acceleration with Large-Scale Structure

Seshadri Nadathur·Will J. Percival·Florian Beutler·Hans Winther
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Abstract

We examine the cosmological implications of measurements of the void-galaxy cross-correlation at redshift $z=0.57$ combined with baryon acoustic oscillation (BAO) data at $0.1 10σ$ significance from these data alone, independent of the cosmic microwave background and supernovae. Using a nucleosynthesis prior on $Ω_bh^2$, we measure the Hubble constant to be $H_0=72.3\pm1.9\;{\rm km\,s}^{-1}{\rm Mpc}^{-1}$ from BAO+voids at $z<2$, and $H_0=69.0\pm1.2\;{\rm km\,s}^{-1}{\rm Mpc}^{-1}$ when adding Lyman-$α$ BAO at $z=2.34$, both independent of the CMB. Adding voids to CMB, BAO and supernova data greatly improves measurement of the dark energy equation of state, increasing the figure of merit by >40%, but remaining consistent with flat flat $Λ$ cold dark matter.

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Seshadri Nadathur, Will J. Percival, Florian Beutler, Hans Winther. 2020-05-21. Testing Low-Redshift Cosmic Acceleration with Large-Scale Structure. https://doi.org/10.1103/physrevlett.124.221301

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