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arXiv · 2410.21542

Non-parametric reconstruction of the fine structure constant with galaxy clusters

Marcelo Ferreira·Rodrigo F. L. Holanda·Javier E. Gonzalez·L. R. Colaço·Rafael C. Nunes
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Abstract

Testing possible variations in fundamental constants of nature is a crucial endeavor in observational cosmology. This paper investigates potential cosmological variations in the fine structure constant ($\alpha$) through a non-parametric approach, using galaxy cluster observations as the primary cosmological probe. We employ two methodologies based on galaxy cluster gas mass fraction measurements derived from X-ray and Sunyaev-Zeldovich observations, along with luminosity distances from type Ia supernovae. We also explore how different values of the Hubble constant ($H_0$) impact the variation of $\alpha$ across cosmic history. When using the Planck satellite's $H_0$ observations, a constant $\alpha$ is ruled out at approximately the 3$\sigma$ confidence level for $z \lesssim 0.5$. Conversely, employing local estimates of $H_0$ restores agreement with a constant $\alpha$.

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Marcelo Ferreira, Rodrigo F. L. Holanda, Javier E. Gonzalez, L. R. Colaço, Rafael C. Nunes. 2024-10-28. Non-parametric reconstruction of the fine structure constant with galaxy clusters. https://doi.org/10.1140/epjc%2Fs10052-024-13468-0

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