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arxiv: hep-th/9904176 · v1 · submitted 1999-04-26 · ✦ hep-th · astro-ph· gr-qc

Perturbations in k-inflation

Jaume Garriga , V.F. Mukhanov This is my paper
classification ✦ hep-th astro-phgr-qc
keywords k-inflationperturbationsscalarfieldlagrangiantensorusualaddition
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We extend the theory of cosmological perturbations to the case when the ``matter'' Lagrangian is an arbitrary function of the scalar field and its first derivatives. In particular, this extension provides a unified description of known cases such as the usual scalar field and the hydrodynamical perfect fluid. In addition, it applies to the recently proposed k-inflation, which is driven by non-minimal kinetic terms in the Lagrangian. The spectrum of quantum fluctuations for slow-roll and power law k-inflation is calculated. We find, for instance, that the usual ``consistency relation'' between the tensor spectral index and the relative amplitude of scalar and tensor perturbations is modified. Thus, at least in principle, k-inflation is phenomenologically distinguishable from standard inflation.

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