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arXiv · 2412.06756

Can decaying vacuum solve the H_0 Tension?

L. S. Brito·J. F. Jesus·A. A. Escobal·S. H. Pereira
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Abstract

In the present work we analyze two different models of interaction between dark energy and dark matter, also known as vacuum decay models or $\Lambda(t)$CDM models. In both models, when the $H_0$ parameter is constrained by the Planck distance priors, its value is compatible with a higher value of $H_0$, in agreement with SH0ES data, while simultaneously reducing the values of $\Omega_m$ and $\Omega_b$. In both models, we find $H_0=73.1\pm0.86$ at 68\% c.l. by combining Planck+SH0ES data. We also find the decay parameter to be $\varepsilon=0.0197^{+0.0032}_{-0.0027}$ for one model and $\varepsilon=0.0203\pm0.0034$ for the other one. From these analyses, a noninteracting model is excluded at least at $6\sigma$ c.l.! This shows that these types of models are promising in solving or at least alleviating the $H_0$ tension problem. Our analysis also shows a preference for the decay of vacuum into dark matter, in agreement to thermodynamic analyses.

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L. S. Brito, J. F. Jesus, A. A. Escobal, S. H. Pereira. 2024-12-09. Can decaying vacuum solve the H_0 Tension?. https://arxiv.org/abs/2412.06756

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