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arXiv · 2407.10845

Inferring dark energy properties from the scale factor parametrisation

Upala Mukhopadhyay·Sandeep Haridasu·Anjan A Sen·Suhail Dhawan
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Abstract

We propose and implement a novel test to assess deviations from well-established concordance $\Lambda$CDM cosmology while inferring dark energy properties. In contrast to the commonly implemented parametric forms of the dark energy equation-of-state (EoS), we test the validity of the cosmological constant on the more fundamental scale factor [$a(t)$] which determines the expansion rate of the Universe. We constrain our extended `general model' using the late-time observables. The posterior of the dark energy EoS is mainly constrained to be quintessence-like naturally excluding physically unviable regions such as phantom crossings or exponential growth.

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Upala Mukhopadhyay, Sandeep Haridasu, Anjan A Sen, Suhail Dhawan. 2024-07-15. Inferring dark energy properties from the scale factor parametrisation. https://doi.org/10.1103/physrevd.110.123516

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