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arXiv · 2305.01224

Machine learning cosmic backreaction and its effects on observations

S. M. Koksbang
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Abstract

Symbolic expressions for cosmic backreaction and mean redshift drift in a range of 2-region models in terms of average quantities are presented. The demonstration that these expressions can be obtained constitutes the opening of a new avenue towards understanding the effects of cosmic backreaction in our universe: With a symbolic expression for the redshift drift at hand, the redshift drift can be used to constrain cosmological parameters including the large-scale expansion rate and backreaction. In addition, by introducing symbolic expressions for cosmic backreaction, this quantity can be constrained with observations such as redshift-distance measures.

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S. M. Koksbang. 2023-05-02. Machine learning cosmic backreaction and its effects on observations. https://doi.org/10.1103/physrevlett.130.201003

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