TITLE:
Constraints on Dynamical Dark Energy with Precision Cosmological Data
AUTHORS:
Erick Almaraz, Axel de la Macorra
KEYWORDS:
Cosmology, Dark Energy, Scalar Fields
JOURNAL NAME:
Journal of Modern Physics,
Vol.9 No.2,
January
29,
2018
ABSTRACT: We present a Dark Energy (DE) model based on a scalar field with an inverse power law potential (IPL) V(∅)=M4+n∅−n. We consider three different models n=1/2, n=3/4 and n=1 and we vary the value of M and the initial amount of energy density Ω∅ at the scale factor ac. We obtain a time dependent equation of state (EoS) , with w∅=1/3 at early times for a scale factor ac with a steep transition to w∅=1 at , , , lasting a long period of time and a subsequent descent w∅=-1 to for to finally grow to w∅= -0.906, w∅=-0.932, w∅=-0.924 for n=1/2, n=3/4 and n=1 respectively. The values of M and Ω∅(ac) are M(eV)= 4.63,127.31,2465.46 and Ω∅(ac)=0.038,0.148,0.227 for n= 1/2, n= 3/4 and n=1 respectively. We show the differences in the evolution of H, the CMB and Matter power spectra, and the redshift space distortion (RSD)parameter. Precision cosmological data allow us to test the dynamics of Dark Energy and we obtain in all three cases a reduction of compared to ∧CDM with and an equivalent fit for CMB and SNIa data.