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arXiv · 1712.05746

Observational Constraints on Oscillating Dark-Energy Parametrizations

Abstract

We perform a detailed confrontation of various oscillating dark-energy parame-trizations with the latest sets of observational data. In particular, we use data from Joint Light Curve analysis (JLA) sample from Supernoave Type Ia, Baryon Acoustic Oscillations (BAO) distance measurements, Cosmic Microwave Background (CMB) observations, redshift space distortion, weak gravitational lensing, Hubble parameter measurements from cosmic chronometers, and we impose constraints on four oscillating models. From the analyses we find that the best-fit characters of almost all models are bent towards the phantom region, nevertheless in all of them the quintessential regime is also allowed within 1$\sigma$ confidence-level. Furthermore, the deviations from $\Lambda$CDM cosmology are not significant, however for two of the models they could be visible at large scales, through the impact on the temperature anisotropy of the CMB spectra and on the matter power spectra. Finally, we peform the Bayesian analysis, which shows that the current observational data support the $\Lambda$CDM paradigm over this set of oscillating dark-energy parametrizations.

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Supriya Pan, Emmanuel N. Saridakis, Weiqiang Yang. 2017-12-15. Observational Constraints on Oscillating Dark-Energy Parametrizations. https://doi.org/10.1103/physrevd.98.063510

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