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arXiv · 0801.0742

Reconstructing a general inflationary action

Rachel Bean·Daniel J. H. Chung·Ghazal Geshnizjani
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Abstract

If inflation is to be considered in an unbiased way, as possibly originating from one of a wide range of underlying theories, then observations need not be simply applied to reconstructing the inflaton potential, V(ϕ), or a specific kinetic term, as in DBI inflation, but rather to reconstruct the inflationary action in its entirety. We discuss the constraints that can be placed on a general single field action from measurements of the primordial scalar and tensor fluctuation power spectra and non-Gaussianities. We also present the flow equation formalism for reconstructing a general inflationary Lagrangian, L(X,ϕ), with X={1/2}\partial_μϕ\partial^μϕ, in a general gauge, that reduces to canonical and DBI inflation in the specific gauge \partial L/\partial X = c_s^{-1}.

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Rachel Bean, Daniel J. H. Chung, Ghazal Geshnizjani. 2008-04-02. Reconstructing a general inflationary action. https://doi.org/10.1103/physrevd.78.023517

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