Unphysical properties in a class of interacting dark energy models
| Autor: | von Marttens, R., Borges, H. A., Carneiro, S., Alcaniz, J. S., Zimdahl, W. |
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| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Eur. Phys. J. C 80, 1110 (2020) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1140/epjc/s10052-020-08682-5 |
| Popis: | Models with non-gravitational interactions between the dark matter and dark energy components are an alternative to the standard cosmological scenario. These models are characterized by an interaction term, and a frequently used parameterization is $Q = 3\xi H \rho_{x}$, where $H$ is the Hubble parameter and $\rho_{x}$ is the dark energy density. Although current observations support such a model for negative values of the interaction parameter $\xi$, we show here that this interval of values of $\xi$ leads the model to predict a violation of the Weak Energy Condition (WEC) for the dark matter density, regardless of the value of the equation-of-state parameter of the dark energy component. This violation is accompanied by unphysical instabilities of matter perturbations. Comment: 17 pages, 7 figures. Accepted for publication in the EPJC |
| Databáze: | arXiv |
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