Revisiting the Hubble tension with an inverse power-law early dark energy

Quan Zhou; Sibo Zheng

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arXiv · 2608.26507

Revisiting the Hubble tension with an inverse power-law early dark energy

Quan Zhou·Sibo Zheng

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Abstract

We propose a new early dark energy with a potential that has an inverse power-law asymptotic tail to alleviate the Hubble tension. Fitting this model to the datasets of CMB+BAO+SN+H0DN, one obtains a 68$\%$ confidence-level value of $H_0\sim 70.20^{+0.60}_{-0.47}$ km s$^{-1}$Mpc$^{-1}$ and a best-fit value of $H_0\sim 70.56$ km s$^{-1}$Mpc$^{-1}$ for index $n=10$. We show that this model can be tested by future data of CMB and matter power spectra. Finally, we briefly discuss fine-tuning problems related to this model.

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Quan Zhou, Sibo Zheng. 2026-08-27. Revisiting the Hubble tension with an inverse power-law early dark energy. https://arxiv.org/abs/2608.26507

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