{"paper":{"title":"The Dark Energy Cosmic Clock: A New Way to Parametrise the Equation of State","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-th"],"primary_cat":"astro-ph.CO","authors_text":"Antonio Padilla, Constantinos Skordis, Edmund J. Copeland, Ewan R. M. Tarrant","submitted_at":"2013-04-19T20:07:57Z","abstract_excerpt":"We propose a completely new parametrisation of the dark energy equation of state, which uses the dark energy density, $\\Omega_e$ as a cosmic clock. We expand the equation of state in a series of orthogonal polynomials, with $\\Omega_e$ as the expansion parameter and determine the expansion coefficients by fitting to SNIa and $H(z)$ data. Assuming that $\\Omega_e$ is a monotonic function of time, we show that our parametrisation performs better than the popular Chevallier--Polarski--Linder (CPL) and Gerke and Efstathiou (GE) parametrisations, and we demonstrate that it is robust to the choice of "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1304.5532","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}