English

Reaffirming the Cosmic Acceleration without Supernova and CMB

Cosmology and Nongalactic Astrophysics 2020-12-15 v2 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

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\Lambda 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 ({\it without} a CMB prior on the acoustic scale), gravitational strong lens time delay, and passively evolving early galaxies as cosmic chronometers, we obtain 4σ\gtrsim 4\sigma detections of cosmic acceleration for both flat and nonflat PAge universes. In the nonflat case, we find a 3σ\gtrsim 3\sigma tension between the spatial curvatures derived from baryon acoustic oscillations and strong lens time delay. Implications and possible systematics are discussed.

Keywords

Cite

@article{arxiv.2008.00487,
  title  = {Reaffirming the Cosmic Acceleration without Supernova and CMB},
  author = {Xiaolin Luo and Zhiqi Huang and Qiyue Qian and Lu Huang},
  journal= {arXiv preprint arXiv:2008.00487},
  year   = {2020}
}

Comments

7 pages; 3 figures

R2 v1 2026-06-23T17:35:06.920Z