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arXiv · 2108.13317

Interacting dark energy axions in light of the Hubble tension

Ennis Mawas·Lauren Street·Richard Gass·L. C. R. Wijewardhana
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Abstract

A current problem within the ΛCDM framework is the tension between late and early time measurements of the Hubble parameter today, H0. We entertain the possibility that dark energy modeled as multiple interacting axion-like-particle species can alleviate the current Hubble tension. We then test these parameters against the milder tension between the CMB and large scale structure (LSS) observations of σ8 to ensure that these models do not exacerbate the tension. We find that there exist parameter spaces for models of two and three axion-like-particles which can potentially alleviate the Hubble tension as well as the σ8 tension.

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Ennis Mawas, Lauren Street, Richard Gass, L. C. R. Wijewardhana. 2021-08-30. Interacting dark energy axions in light of the Hubble tension. https://arxiv.org/abs/2108.13317

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