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arXiv · 2512.06701

What Galaxy Clusters Have to Say About Dynamical Dark Energy and $H_0$

Andrés N. Salcedo·Eduardo Rozo·Hao-Yi Wu·Shulei Cao·Enrique Paillas·Hanyu Zhang·Eli S. Rykoff
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Abstract

We show that, in flat $\Lambda$CDM, low-redshift structure probes -- cluster abundances, 3$\times$2-point analyses, and full-shape clustering -- are mutually consistent, jointly delivering precise constraints on $\sigma_8$ and $\Omega_{\rm m}$ that agree with geometrical datasets (CMB+BAO+SN). In $w_0w_a$CDM, adding clusters to the geometry dataset reduces the evidence for evolving dark energy while relaxing the $H_0$ tension, suggesting a $\Lambda$CDM evolution of the late-time Universe and a sound horizon that differs from its standard value.

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Andrés N. Salcedo, Eduardo Rozo, Hao-Yi Wu, Shulei Cao, Enrique Paillas, Hanyu Zhang, Eli S. Rykoff. 2025-12-07. What Galaxy Clusters Have to Say About Dynamical Dark Energy and $H_0$. https://arxiv.org/abs/2512.06701

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