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arXiv · 2603.15067

The peculiar case of the Viaggiu holographic dark energy

Somnath Saha·Subhajit Saha·Nilanjana Mahata
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Abstract

We study the plausibility of a holographic dark energy (HDE) model using the form of horizon entropy proposed by Viaggiu in 2014. This form of entropy is a generalization of the usual Bekenstein-Hawking entropy, having an extra term arising due to the dynamical nature of horizons in an expanding universe. We examine this new HDE model in the context of a flat Friedmann-Lema\^itre-Robertson-Walker universe filled with two cosmic fluids -- dark matter in the form of dust and holographic dark energy generated by Viaggiu entropy. We consider the Hubble horizon and the future event horizon as characteristic length scales and study the evolution of the Universe within these frameworks. Our analysis reveals some intriguing findings that include a possible cosmic doomsday scenario in the future, and certain observations are in striking contrast to other HDE models studied in the literature.

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Somnath Saha, Subhajit Saha, Nilanjana Mahata. 2026-03-16. The peculiar case of the Viaggiu holographic dark energy. https://doi.org/10.1016/j.nuclphysb.2026.117368

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