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arXiv · 2608.25159

21-cm Brightness Temperature in a Unified-Dark-Sector Horndeski Theory

Bertha Cuadros-Melgar·Thanasis Karakasis·Eleftherios Papantonopoulos·Maria Petronikolou
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Abstract

We investigate the impact of scalar-tensor theories on the 21cm brightness temperature. We consider a specific model in Horndeski scalar-tensor theory in which dark matter and dark energy in the framework of shift-symmetric generalized Galileon theories was described and an effective unified cosmic fluid was obtained. We calculate the Hubble parameter of the model and we plot the curve of the evolution of the 21-cm temperature in a specific range of the redshift parameter $z$ and compare it to the curve corresponding to $\Lambda$CDM paradigm.

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Bertha Cuadros-Melgar, Thanasis Karakasis, Eleftherios Papantonopoulos, Maria Petronikolou. 2026-08-25. 21-cm Brightness Temperature in a Unified-Dark-Sector Horndeski Theory. https://arxiv.org/abs/2608.25159

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