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arXiv · 2204.09693

Generalized McVittie geometry in Horndeski gravity with matter

Marcello Miranda·Daniele Vernieri·Salvatore Capozziello·Valerio Faraoni
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Abstract

We investigate McVittie and generalized McVittie solutions for Horndeski gravity with a spatially homogeneous gravitational scalar field, which is stealth at small scales near the central object but, at large scales, sources the FLRW universe in which the central inhomogeneity is embedded. Unlike previous studies, we include matter and obtain generalized McVittie solutions in the extended cuscuton model. The possible configurations are classified according to the time-dependence of the gravitational coupling, the radial energy flow, the accretion rate onto the central object, and the Hubble rate.

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Marcello Miranda, Daniele Vernieri, Salvatore Capozziello, Valerio Faraoni. 2022-04-20. Generalized McVittie geometry in Horndeski gravity with matter. https://doi.org/10.1103/physrevd.105.124024

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