Spatial Ricci scalar dark energy model

TL;DR

This paper proposes a dark energy model based on the spatial Ricci scalar curvature, fitting observational data well and showing a transition from deceleration to acceleration around redshift 0.4, with minimal impact on matter power spectra.

Contribution

It introduces a phenomenologically viable dark energy model linked to Ricci scalar curvature, constrained by supernova and BAO data, and analyzes its cosmological implications.

Findings

Best-fit parameters: Ω_m0=0.259±0.016, α=0.261±0.0122

Equation of state crosses -1 at z≈-0.14

Deceleration to acceleration transition at z≈0.4

Abstract

Inspired by holographic principle, we suggest that the density of dark energy is proportional to the spatial Ricci scalar curvature (SRDE). Such model is phenomenologically viable. The best fit values of its parameters at 68% confidence level are found to be: $\Omega_{\rm m0}=0.259\pm0.016$ and $\alpha=0.261\pm0.0122$, constrained from the Union+CFA3 sample of 397 SNIa and the BAO measurement. We find the equation of state of SRDE crosses -1 at $z\simeq-0.14$. The present values of the deceleration parameter $q(z)$ for SRDE is found to be $q_{z=0}\sim -0.85$. The phase transition from deceleration to acceleration of the Universe for SRDE occurs at the redshift $z_{q=0}\sim 0.4$. After studying on the perturbation of each component of the Universe, we show that the matter power spectra and cosmic microwave background temperature anisotropy is slightly affected by SRDE, compared with $\Lambda$CDM.