Tracing the equation of state and the density of cosmological constant along z

TL;DR

This paper reconstructs the dark energy equation of state w(z) using high-redshift supernova data, demonstrating improved constraints on dark energy density variation with new observations.

Contribution

It introduces a non-parametric reconstruction method combining inverse problem and Monte Carlo techniques to analyze high-z supernova data for dark energy properties.

Findings

High-z supernova data improve constraints on w(z)

Reconstructed w(z) shows potential evolution at high redshift

Method offers prospects for measuring dark energy density variation

Abstract

We investigate the equation of state w(z) in a non-parametric form using the latest compilations of distance luminosity from SNe Ia at high z. We combine the inverse problem approach with a Monte Carlo to scan the space of priors. On the light of these high redshift supernova data sets, we reconstruct w(z). A comparison between a sample including the latest results at z>1 and a sample without those results show the improvement achieved by observations of very high z supernovae. We present the prospects to measure the variation of dark energy density along z by this method.