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تسجيل مستخدم جديدTesting Low-Redshift Cosmic Acceleration with Large-Scale Structure
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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 $0.1<z<2.4$. We find direct evidence of the late-time acceleration due to dark energy at $>10sigma$ significance from these data alone, independent of the cosmic microwave background and supernovae. Using a nucleosynthesis prior on $Omega_bh^2$, we measure the Hubble constant to be $H_0=72.3pm1.9;{rm km,s}^{-1}{rm Mpc}^{-1}$ from BAO+voids at $z<2$, and $H_0=69.0pm1.2;{rm km,s}^{-1}{rm Mpc}^{-1}$ when adding Lyman-$alpha$ 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 $Lambda$ cold dark matter.
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