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Liberating the Inflaton from Primordial Spectrum Constraints

C. Armendariz-Picon
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Abstract

I discuss a mechanism that renders the spectral index of the primordial spectrum and the inflationary stage independent of each other. If a scalar field acquires an appropriate time-dependent mass, it is possible to generate an adiabatic, Gaussian scale invariant spectrum of density perturbations during any stage of inflation. As an illustration, I present a simple model where the time-dependent mass arises from the coupling of the inflaton to a second scalar. The mechanism I propose might help to implement a successful inflationary scenario in particle physics theories that do not yield slow-roll potentials.

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C. Armendariz-Picon. 2003-10-17. Liberating the Inflaton from Primordial Spectrum Constraints. https://doi.org/10.1088/1475-7516%2F2004%2F03%2F009

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