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arXiv · 2305.20038

Cosmic-Dawn 21-cm Signal from Dynamical Dark Energy

Lu Yin
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Abstract

The 21-cm signal is the most important measurement for us to understand physics during cosmic dawn. It is the key for us to understand the expansion history of the Universe and the nature of dark energy. In this paper, we focused on the characteristic 21-cm power spectrum of a special dynamic dark energy - the Interacting Chevallier-Polarski-Linder (ICPL) model - and compared it with those of the $\Lambda$CDM and CPL models. From the expected noise of HERA, we found more precise experiments in the future can detect the features of interacting dark energy in the 21-cm power spectra. By studying the brightness temperature, we found the ICPL model is closer to the observation of EDGES compared to the $\Lambda$CDM, thus alleviating the tension between theory and experiments.

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Lu Yin. 2023-05-31. Cosmic-Dawn 21-cm Signal from Dynamical Dark Energy. https://arxiv.org/abs/2305.20038

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