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arXiv · 2110.07569

BD-$\Lambda$CDM and Running Vacuum Models: Theoretical background and current observational status

Javier de Cruz Perez·Joan Sola Peracaula·Adria Gomez-Valent·Cristian Moreno-Pulido
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Abstract

We present an analysis of the Brans-Dicke cosmological model with a cosmological constant and cold dark matter (BD-$\Lambda$CDM). We find that the BD-$\Lambda$CDM is favored by the overall cosmological data (SNIa+BAO+$H(z)$+LSS+CMB) when it is compared with the standard model of cosmology. The BD-$\Lambda$CDM model can be viewed from the GR perspective as a Running Vacuum Model (RVM) with a time evolving vacuum energy density. Due to this fact and also to its time evolving effective gravitational coupling, the model can alleviate the $\sigma_8$ and the $H_0$ tensions at a time. We also present the results for different types of RVM's when they are tested in the light of the cosmological data and we show that a mild dynamics for the vacuum energy density can help to smooth out the aforementioned tensions, thus improving the performance of $\Lambda$CDM model.

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Javier de Cruz Perez, Joan Sola Peracaula, Adria Gomez-Valent, Cristian Moreno-Pulido. 2021-10-14. BD-$\Lambda$CDM and Running Vacuum Models: Theoretical background and current observational status. https://arxiv.org/abs/2110.07569

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