2020/11/30 by W. J. C. da Silva, R. Silva
Physics and Astronomy · #Astrophysics #Baryon acoustic oscillations #Cold dark matter #Context (archaeology) #Cosmology #Cosmology and Gravitation Theories #Dark energy #Dark fluid #Dark matter #Galaxies: Formation, Evolution, Phenomena #Lambda #Mathematical physics #Mechanics #Physics #Quantum mechanics #Redshift #Sigma #Stellar, planetary, and galactic studies #Theoretical physics #Viscous liquid #astro-ph.CO
paper · pdf · doi:10.1140/epjc/s10052-021-09177-7
published as Eur.Phys.J.C 81 (2021) 5, 403 · 19 pages, 8 figures, 8 tables. Updated to match the published version
openalex publication_date 2021/05/01 · arxiv created 2021/05/12 · arxiv updated 2021/05/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract In this work, we study the extended viscous dark energy models in the context of matter perturbations. To do this, we assume an alternative interpretation of the flat Friedmann–Lemaître–Robertson–Walker Universe, through the nonadditive entropy and the viscous dark energy. We implement the relativistic equations to obtain the growth of matter fluctuations for a smooth version of dark energy. As result, we show that the matter density contrast evolves similarly to the Λ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Λ</mml:mi> </mml:math> CDM model in high redshift; however, in late time, it is slightly different from the standard model. Using the latest geometrical and growth rate observational data, we carry out a Bayesian analysis to constrain parameters and compare models. We see that our viscous models are compatible with cosmological probes, and the Λ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Λ</mml:mi> </mml:math> CDM recovered with a 1σ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>1</mml:mn> <mml:mi>σ</mml:mi> </mml:mrow> </mml:math> confidence level. The viscous dark energy models relieve the tension of H0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>H</mml:mi> <mml:mn>0</mml:mn> </mml:msub> </mml:math> in 2 ∼ 3 σ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>2</mml:mn> <mml:mo>∼</mml:mo> <mml:mn>3</mml:mn> <mml:mi>σ</mml:mi> </mml:mrow> </mml:math> . Yet, by involving the σ 8 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>σ</mml:mi> <mml:mn>8</mml:mn> </mml:msub> </mml:math> tension, some models can alleviate it. In the model selection framework, the data discards the extended viscous dark energy models.