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arXiv · 2210.13946

Dynamical analysis of the redshift drift in FLRW universes

Francisco S. N. Lobo·José Pedro Mimoso·Jessica Santiago·Matt Visser
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Abstract

Redshift drift is the phenomenon whereby the observed redshift between an emitter and observer comoving with the Hubble flow in an expanding FLRW universe will slowly evolve -- on a timescale comparable to the Hubble time. In a previous article [JCAP 04 (2020) 043; arXiv 2001.11964] three of the current authors had performed a cosmographic analysis of the redshift drift in a FLRW universe, temporarily putting aside the issue of dynamics (the Friedmann equations). In the current article we now add dynamics, still within the framework of an exact FLRW universe. We shall develop a suitable generic matter model and apply it to both standard FLRW and various dark energy models. Furthermore, we shall also present a section analyzing the utility of using alternative cosmographic variables to describe the redshift drift data.

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Francisco S. N. Lobo, José Pedro Mimoso, Jessica Santiago, Matt Visser. 2022-10-25. Dynamical analysis of the redshift drift in FLRW universes. https://doi.org/10.3390/universe10040162

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