Sub-Planckian two-field inflation consistent with the Lyth bound

McDonald, John (2014) Sub-Planckian two-field inflation consistent with the Lyth bound. Journal of Cosmology and Astroparticle Physics, 2014 (9). ISSN 1475-7516

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Abstract

The BICEP2 observation of a large tensor-to-scalar ratio, r = 0.20(-0.05)(+0.07), implies that the inflaton phi in single-field inflation models must satisfy phi similar to 10 M-Pl in order to produce sufficient inflation. This is a problem if interaction terms suppressed by the Planck scale impose a bound phi less than or similar to M-Pl. Here we consider whether it is possible to have successful sub-Planckian inflation in the case of two-field inflation. The trajectory in field space cannot be radial if the effective single-field inflaton is to satisfy the Lyth bound. By considering a complex field Phi, we show that a near circular but aperiodic modulation of a vertical bar Phi vertical bar(4) potential can reproduce the results of phi(2) chaotic inflation for n(s) and r while satisfying vertical bar Phi vertical bar less than or similar to 0.01 M-Pl throughout. More generally, for models based on a vertical bar Phi vertical bar(4) potential, the simplest sub-Planckian models are equivalent to phi(2) and phi(4/3) chaotic inflation.

Item Type:
Journal Article
Journal or Publication Title:
Journal of Cosmology and Astroparticle Physics
Additional Information:
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.
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3100/3103
Subjects:
ID Code:
73285
Deposited By:
Deposited On:
12 Mar 2015 15:00
Refereed?:
Yes
Published?:
Published
Last Modified:
05 Dec 2020 02:42