Signatures of Planck corrections in a spiralling axion inflation model

McDonald, John (2015) Signatures of Planck corrections in a spiralling axion inflation model. Journal of Cosmology and Astroparticle Physics (5). ISSN 1475-7516

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The minimal sub-Planckian axion inflation model accounts for a large scalar-to-tensor ratio via a spiralling trajectory in the field space of a complex field Phi. Here we consider how the predictions of the model are modified by Planck scale-suppressed corrections. In the absence of Planck corrections the model is equivalent to a phi(4/3) chaotic inflation model. Planck corrections become important when the dimensionless coupling xi of |Phi|(2) to the topological charge density of the strongly-coupled gauge sector F (F) over tilde satisfies xi similar to 1. For values of |Phi| which allow the Planck corrections to be understood via an expansion in powers of |Phi|(2)/M-P1(2), we show that their effect is to produce a significant modification of the tensor-to-scalar ratio from its phi(4/3) chaotic inflation value without strongly modifying the spectral index. In addition, to leading order in |Phi|(2)/M-P1(2), the Planck modifications of n(s) and r satisfy a consistency relation, Delta n(s) = -Delta r/16. Observation of these modifications and their correlation would allow the model to be distinguished from a simple phi(4/3) chaotic inflation model and would also provide a signature for the influence of leading-order Planck corrections.

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Journal Article
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Journal of Cosmology and Astroparticle Physics
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Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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11 Dec 2015 11:04
Last Modified:
07 Jul 2020 04:12