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arXiv · 1603.03883

Hamilton-Jacobi formalism for inflation with non-minimal derivative coupling

Haidar Sheikhahmadi·Emmanuel N. Saridakis·Ali Aghamohammadi·Khaled Saaidi
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Abstract

In inflation with nonminimal derivative coupling there is not a conformal transformation to the Einstein frame where calculations are straightforward, and thus in order to extract inflationary observables one needs to perform a detailed and lengthy perturbation investigation. In this work we bypass this problem by performing a Hamilton-Jacobi analysis, namely rewriting the cosmological equations considering the scalar field to be the time variable. We apply the method to two specific models, namely the power-law and the exponential cases, and for each model we calculate various observables such as the tensor-to-scalar ratio, and the spectral index and its running. We compare them with 2013 and 2015 Planck data, and we show that they are in a very good agreement with observations.

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Haidar Sheikhahmadi, Emmanuel N. Saridakis, Ali Aghamohammadi, Khaled Saaidi. 2016-03-12. Hamilton-Jacobi formalism for inflation with non-minimal derivative coupling. https://doi.org/10.1088/1475-7516%2F2016%2F10%2F021

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