Reaffirming the Cosmic Acceleration without Supernova and CMB. (arXiv:2008.00487v1 [astro-ph.CO])
<a href="http://arxiv.org/find/astro-ph/1/au:+Luo_X/0/1/0/all/0/1">Xiaolin Luo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huang_Z/0/1/0/all/0/1">Zhiqi Huang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Qian_Q/0/1/0/all/0/1">Qiyue Qian</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huang_L/0/1/0/all/0/1">Lu Huang</a>
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 $Lambda$ 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 $gtrsim
4sigma$ detections of cosmic acceleration for both flat and nonflat PAge
universes. In the nonflat case, we find a $gtrsim 3sigma$ tension between the
spatial curvatures derived from baryon acoustic oscillations and strong lens
time delay. Implications and possible systematics are discussed.
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 $Lambda$ 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 $gtrsim
4sigma$ detections of cosmic acceleration for both flat and nonflat PAge
universes. In the nonflat case, we find a $gtrsim 3sigma$ tension between the
spatial curvatures derived from baryon acoustic oscillations and strong lens
time delay. Implications and possible systematics are discussed.
http://arxiv.org/icons/sfx.gif
