A symmetry of the Einstein-Friedmann equations for spatially flat,\n perfect fluid, universes

2020/01/07 by Valerio Faraoni, Faraoni, Valerio
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #General Relativity and Quantum Cosmology (gr-qc)

paper · pdf · doi:10.48550/arxiv.2001.02126

openalex publication_date 2020/01/07 · openalex created_date 2022/07/26 · openalex updated_date 2026/07/28

Abstract

We report a symmetry property of the Einstein-Friedmann equations for\nspatially flat Friedmann-Lema ⁱtre-Robertson-Walker universes filled with a\nperfect fluid with any constant equation of state. The symmetry transformations\nform a one-parameter Abelian group.\n

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