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arXiv · 2501.08391

Multi-axion like description of the dark sector in light of the Hubble and $\sigma_8$ tensions

John Dumancic·Richard Gass·Ennis Mawas·L. C. R. Wijewardhana
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Abstract

Local methods of direct determination of the Hubble constant and $\sigma_8$ seem to conflict with the predictions made from the cosmic microwave background and $\Lambda$CDM. We propose a proof-of-concept model that models portions of the dark sector as several coupled axion-like fields, resulting in both early and late time departures from $\Lambda$CDM. We determine that the model successfully eliminates both the Hubble and $\sigma_8$ tensions, while remaining consistent with both the DESI survey and the BAO sound horizon.

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John Dumancic, Richard Gass, Ennis Mawas, L. C. R. Wijewardhana. 2025-01-14. Multi-axion like description of the dark sector in light of the Hubble and $\sigma_8$ tensions. https://arxiv.org/abs/2501.08391

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