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

Cristina Espana-Bonet; Pilar Ruiz-Lapuente

doi:10.1088/1475-7516/2008/02/018

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arXiv · 0805.1929

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

Cristina Espana-Bonet·Pilar Ruiz-Lapuente

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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.

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Cristina Espana-Bonet, Pilar Ruiz-Lapuente. 2008-05-13. Tracing the equation of state and the density of cosmological constant along z. https://doi.org/10.1088/1475-7516%2F2008%2F02%2F018

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