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arXiv · 2310.18757

Analyzing the 21-cm signal brightness temperature in the Universe with inhomogeneities

Shashank Shekhar Pandey·Ashadul Halder·A. S. Majumdar
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Abstract

We explore the 21-cm signal in our Universe containing inhomogeneous matter distribution at considerably large scales. Employing Buchert's averaging procedure in the context of a model of spacetime with multiple inhomogeneous domains, we evaluate the effect of our model parameters on the observable 21-cm signal brightness temperature. Our model parameters are constrained through the Markov Chain Monte Carlo method using the Union 2.1 supernova Ia observational data. We find that a significant dip in the brightness temperature compared to the $\Lambda$CDM prediction could arise as an effect of the inhomogeneities present in the Universe.

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Shashank Shekhar Pandey, Ashadul Halder, A. S. Majumdar. 2023-10-28. Analyzing the 21-cm signal brightness temperature in the Universe with inhomogeneities. https://doi.org/10.1103/physrevd.110.043531

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