Reaffirming the Cosmic Acceleration without Supernovae and the Cosmic Microwave Background
Abstract
Recent discussions about supernova magnitude evolution have raised doubts about the robustness of the late-universe acceleration. In a previous letter, Huang did a null test of the cosmic acceleration by using a Parameterization based on the cosmic Age (PAge), which covers a broad class of cosmological models including the standard Λ cold dark matter model and its many extensions. In this work, we continue to explore the cosmic expansion history with the PAge approximation. Using baryon acoustic oscillations (without a CMB prior on the acoustic scale), gravitational strong lens time delay, and passively evolving early galaxies as cosmic chronometers, we obtain ≳ 4σ detections of cosmic acceleration for both flat and nonflat PAge universes. In the nonflat case, we find a novel ≳3σ tension between the spatial curvatures derived from baryon acoustic oscillations and strong lens time delay. Implications and possible systematics are discussed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 2020
- DOI:
- 10.3847/1538-4357/abc25f
- Bibcode:
- 2020ApJ...905...53L
- Keywords:
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- Dark energy;
- Cosmological models;
- Observational cosmology;
- Baryon acoustic oscillations;
- Strong gravitational lensing;
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