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arXiv · 2402.00055

Accelerating Universe in Terms of Hankel Function Index

K. Suratgar·M. Mohsenzadeh·E. Yusofi·F. Taghizadeh-Farahmand
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Abstract

In this paper, $F(\nu)$ cosmology is proposed for the accelerating universe with asymptotic de Sitter expansion in terms of Hankel function index $\nu$. To some extent, both the initial expansion during early inflation and the current accelerated expansion can be studied with a vacuum cosmic fluid i.e. $\Lambda$ in the pure de Sitter phase. Observational data further support the notion of a quasi-vacuum fluid, rather than a pure vacuum, contributing to the quasi-de Sitter acceleration in both the early and late universe. By examining the asymptotic expansion of the Henkel function as an approximate solution of the Mukhanov-Sasaki equation, we seek a more detailed study of quasi-de Sitter solutions in cosmology containing vacuum-like fluid.

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K. Suratgar, M. Mohsenzadeh, E. Yusofi, F. Taghizadeh-Farahmand. 2024-01-28. Accelerating Universe in Terms of Hankel Function Index. https://doi.org/10.1142/s021773232350178x

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