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arXiv · 1806.06791

Deformed general relativity and scalar-tensor models

Rhiannon Cuttell·Mairi Sakellariadou
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Abstract

We calculate the most general action for a scalar-tensor model up to quadratic order in derivatives with deformed general covariance and non-minimal coupling. We demonstrate how different choices of the free functions recover specific well known scalar-tensor models. We look at the cosmological dynamics and find the general conditions for either inflation or a big bounce. Using this we present a novel non-minimally coupled scalar model which produces a bounce, and describe how to find similar models.

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Rhiannon Cuttell, Mairi Sakellariadou. 2018-06-18. Deformed general relativity and scalar-tensor models. https://doi.org/10.1088/1361-6382%2Faae442

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