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arXiv · 1210.7166

Probing dark energy with redshift-drift

Matteo Martinelli·Stefania Pandolfi·C. J. A. P. Martins·P. E. Vielzeuf
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Abstract

Future redshift-drift measurements (also known as Sandage-Loeb signal) will be crucial to probe the so called "redshift desert", thus providing a new tool for cosmological studies. In this paper we quantify the ability of a future measurement of the Sandage-Loeb signal by a CODEX-like spectrograph to constrain a phenomenological parametrization of dynamical dark energy, specifically by obtaining constraints on $w_0$ and $w_a$. We also demonstrate that if used alongside CMB data, the Sandage-Loeb measurements will be able to break degeneracies between expansion parameters, thus greatly improving cosmological constraints.

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Matteo Martinelli, Stefania Pandolfi, C. J. A. P. Martins, P. E. Vielzeuf. 2012-11-19. Probing dark energy with redshift-drift. https://doi.org/10.1103/physrevd.86.123001

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