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Perturbation evolution with a non-minimally coupled scalar field

Rachel Bean
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Abstract

We recently proposed a simple dilaton-derived quintessence model in which the scalar field was non-minimally coupled to cold dark matter, but not to `visible' matter. Such couplings can be attributed to the dilaton in the low energy limit of string theory, beyond tree level. In this paper we discuss the implications of such a model on structure formation, looking at its impact on matter perturbations and CMB anisotropies. We find that the model only deviates from $Λ$CDM and minimally coupled theories at late times, and is well fitted to current observational data. The signature left by the coupling, when it breaks degeneracy at late times, presents a valuable opportunity to constrain non-minimal couplings given the wealth of new observational data promised in the near future.

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Rachel Bean. 2001-08-30. Perturbation evolution with a non-minimally coupled scalar field. https://doi.org/10.1103/physrevd.64.123516

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