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arXiv · 2310.12932

Reconciling early dark energy with a Harrison-Zeldovich spectrum

Chengjie Fu·Shao-Jiang Wang
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Abstract

Recent attempts to fully resolve the Hubble tension from early dark energy models seem to favor a primordial Harrison-Zeldovich universe with its scalar spectrum being extremely scale invariant. Restoring the Harrison-Zeldovich spectrum within the single-field inflationary paradigm appears to be infeasible, turning to the multifield approach from either curvaton or waterfall models. In this Letter, we successfully align with the Harrison-Zeldovich spectrum within a single-field chaotic inflation by a nonminimal derivative coupling, and the previously disfavored chaotic potential by Planck+BICEP/Keck data in the standard $\Lambda$-cold-dark-matter model now returns back to the scope of future polarization observations of the cosmic microwave background.

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Chengjie Fu, Shao-Jiang Wang. 2023-10-19. Reconciling early dark energy with a Harrison-Zeldovich spectrum. https://doi.org/10.1103/physrevd.109.l041304

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