Weiqiang Yang

Effects of neutrino mass hierarchies on dynamical dark energy models

We investigate how three different possibilities of neutrino mass hierarchies, namely normal, inverted, and degenerate, can affect the observational constraints on three well known dynamical dark energy models, namely the Chevallier-Polarski-Linder, logarithmic, and the Jassal-Bagla-Padmanabhan parametrizations. In order to impose the observational constraints on the models, we performed a robust analysis using Planck 2015 temperature and polarization data, Supernovae type Ia from Joint Light curve analysis, baryon acoustic oscillations distance measurements, redshift space distortion characterized by

Cosmological constraints on coupled dark energy

f(z)\sigma_8(z)

Cosmic constraint on massive neutrinos in viable f(R) gravity with producing \(\Lambda \) CDM background expansion

data, weak gravitational lensing data from Canada-France-Hawaii Telescope Lensing Survey, and cosmic chronometers data plus the local value of the Hubble parameter. We find that different neutrino mass hierarchies return similar fit on almost all model parameters and mildly change the dynamical dark energy properties.

Latest astronomical constraints on some non-linear parametric dark energy models

The coupled dark energy model provides a possible approach to mitigate the coincidence problem of cosmological standard model. Here, the coupling term is assumed as

Tale of stable interacting dark energy, observational signatures, and the H0 tension

\bar{Q}=3H\xi_x\bar{\rho}_x

Large-scale (in) stability analysis of an exactly solved coupled dark-energy model

, which is related to the interaction rate and energy density of dark energy. We derive the background and perturbation evolution equations for several coupled models. Then, we test these models by currently available cosmic observations which include cosmic microwave background radiation from Planck 2015, baryon acoustic oscillation, type Ia supernovae,

Testing the Interacting Dark Energy Model with Cosmic Microwave Background Anisotropy and Observational Hubble Data

f\sigma_8(z)

Cosmological implications of the dark matter equation of state

data points from redshift-space distortions, and weak gravitational lensing. The constraint results tell us there is no evidence of interaction at 2

Late-time acceleration with steep exponential potentials

\sigma

Constraining a dark matter and dark energy interaction scenario with a dynamical equation of state

level, it is very hard to distinguish different coupled models from other ones.