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arXiv · 2407.16685

Fractional Holographic Dark Energy

Oem Trivedi·Ayush Bidlan·Paulo Moniz
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Abstract

Holographic dark energy theories present a fascinating interface to probe late-time cosmology, as guided by contemporary ideas about quantum gravity. In this work, we present a new holographic dark energy scenario designated Fractional Holographic Dark Energy (FHDE). This model extends the conventional framework of HDEs by incorporating specific features from fractional calculus recently applied, e.g., in cosmological settings. In this manner, we retrieve a novel form of HDE energy density. We then show how FHDE can provide a consistent picture of the evolution of the late-time universe even with the simple choice of the Hubble horizon as the IR (infrared) cutoff. We provide detailed descriptions of the cosmological evolution, showing how the fractional calculus ingredients can alleviate quite a few issues associated with the conventional HDE scenario. Concretely, we compute and plot diagrams using the Hubble horizon cutoff for HDE. The density parameters for DE and dark matter (DM), the deceleration parameter, and the DE EoS parameter indicate how the universe may evolve within our FHDE model, fitting within an appropriate scenario of late-time cosmology.

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Oem Trivedi, Ayush Bidlan, Paulo Moniz. 2024-07-23. Fractional Holographic Dark Energy. https://doi.org/10.1016/j.physletb.2024.139074

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