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arXiv · 1606.00711

$k$-essence non-minimally coupled with Gauss-Bonnet invariant for inflation

Ratbay Myrzakulov·Lorenzo Sebastiani
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Abstract

In this paper, we investigated inflationary solutions for a subclass of Horndeski models where a scalar field is non-minimally coupled with the Gauss-Bonnet invariant. Examples of canonical scalar field and $k$-essence to support the early-time acceleration are considered. The formalism to calculate the perturbations in FRW universe and to derive the spectral index and the tensor-to-scalar ratio is furnished.

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Ratbay Myrzakulov, Lorenzo Sebastiani. 2016-06-28. $k$-essence non-minimally coupled with Gauss-Bonnet invariant for inflation. https://doi.org/10.3390/sym8070057

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