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arXiv · 2411.07060

Running Hubble constant: evolutionary Dark Energy

Giovanni Montani·Nakia Carlevaro·Maria G. Dainotti
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Abstract

We discuss an evolutionary dark energy model, based on the presence of non-equilibrium effects on the dark energy constituents, which are described via a bulk viscosity contribution. We implement the proposed dynamics by the analysis of the 40-bins Type Ia Supernovae (SNe) Pantheon sample data, in order to outline the existence of a running Hubble constant with the redshift. Via a fitting procedure, we determine the value of the additional parameter that our model possesses with respect a standard $\Lambda$ Cold Dark Matter ($\Lambda$CDM) scenario. As important result, the evolutionary dark energy proposal seems more appropriate to describe the binned SN analysis with respect to the $\Lambda$CDM Hubble parameter, i.e. a non running value for the Hubble constant over the bins.

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Giovanni Montani, Nakia Carlevaro, Maria G. Dainotti. 2024-11-11. Running Hubble constant: evolutionary Dark Energy. https://doi.org/10.1016/j.dark.2025.101847

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