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arXiv · 2012.09946

Anisotropic solid dark energy

J. Motoa-Manzano·J. Bayron Orjuela-Quintana·Thiago S. Pereira·César A. Valenzuela-Toledo
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Abstract

In this paper, we study a triad of inhomogeneous scalar fields, known as "solid", as a source of homogeneous but anisotropic dark energy. By using a dynamical system approach, we find that anisotropic accelerated solutions can be realized as attractor points for suitable choices of the parameters of the model. We complement the dynamical analysis with a numerical solution whose initial conditions are set in the deep radiation epoch. The model can give an account of a non-negligible spatial shear within the observational bounds nowadays, even when the later is set to zero at early times. However, we find that there is a particular region in the parameter space of the model in which the Universe isotropizes. The anisotropic attractors, the particular isotropic region, and a nearly constant equation of state of dark energy very close to $- 1$ are key features of this scenario. Following a similar approach, we also analyzed the full isotropic version of the model. We find that the solid can be characterized by a constant equation of state and thus being able to simulate the behavior of a cosmological constant.

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J. Motoa-Manzano, J. Bayron Orjuela-Quintana, Thiago S. Pereira, César A. Valenzuela-Toledo. 2020-12-17. Anisotropic solid dark energy. https://doi.org/10.1016/j.dark.2021.100806

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