# Signatures of Planck corrections in a spiralling axion inflation model

## Abstract

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 Φ. 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 ϕ{sup 4/3} chaotic inflation model. Planck corrections become important when the dimensionless coupling ξ of |Φ|{sup 2} to the topological charge density of the strongly-coupled gauge sector FF{sup ~} satisfies ξ∼1. For values of |Φ| which allow the Planck corrections to be understood via an expansion in powers of |Φ|{sup 2}/M{sub Pl}{sup 2}, we show that their effect is to produce a significant modification of the tensor-to-scalar ratio from its ϕ{sup 4/3} chaotic inflation value without strongly modifying the spectral index. In addition, to leading order in |Φ|{sup 2}/M{sub Pl}{sup 2}, the Planck modifications of n{sub s} and r satisfy a consistency relation, Δn{sub s}=−Δr/16. Observation of these modifications and their correlation would allow the model to be distinguished from a simple ϕ{sup 4/3} chaotic inflation model and would also provide a signature for the influence of leading-order Planck corrections.

- Authors:

- Dept. of Physics, University of Lancaster,Lancaster LA1 4YB (United Kingdom)

- Publication Date:

- Sponsoring Org.:
- SCOAP3, CERN, Geneva (Switzerland)

- OSTI Identifier:
- 22454547

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 05; Other Information: PUBLISHER-ID: JCAP05(2015)014; OAI: oai:repo.scoap3.org:10223; 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.; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AXIONS; CHAOS THEORY; CHARGE DENSITY; CORRECTIONS; COSMOLOGICAL INFLATION; GAUGE INVARIANCE; SCALARS; STRONG-COUPLING MODEL; TENSORS; TOPOLOGY

### Citation Formats

```
McDonald, John.
```*Signatures of Planck corrections in a spiralling axion inflation model*. United States: N. p., 2015.
Web. doi:10.1088/1475-7516/2015/05/014.

```
McDonald, John.
```*Signatures of Planck corrections in a spiralling axion inflation model*. United States. doi:10.1088/1475-7516/2015/05/014.

```
McDonald, John. Fri .
"Signatures of Planck corrections in a spiralling axion inflation model". United States.
doi:10.1088/1475-7516/2015/05/014.
```

```
@article{osti_22454547,
```

title = {Signatures of Planck corrections in a spiralling axion inflation model},

author = {McDonald, John},

abstractNote = {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 Φ. 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 ϕ{sup 4/3} chaotic inflation model. Planck corrections become important when the dimensionless coupling ξ of |Φ|{sup 2} to the topological charge density of the strongly-coupled gauge sector FF{sup ~} satisfies ξ∼1. For values of |Φ| which allow the Planck corrections to be understood via an expansion in powers of |Φ|{sup 2}/M{sub Pl}{sup 2}, we show that their effect is to produce a significant modification of the tensor-to-scalar ratio from its ϕ{sup 4/3} chaotic inflation value without strongly modifying the spectral index. In addition, to leading order in |Φ|{sup 2}/M{sub Pl}{sup 2}, the Planck modifications of n{sub s} and r satisfy a consistency relation, Δn{sub s}=−Δr/16. Observation of these modifications and their correlation would allow the model to be distinguished from a simple ϕ{sup 4/3} chaotic inflation model and would also provide a signature for the influence of leading-order Planck corrections.},

doi = {10.1088/1475-7516/2015/05/014},

journal = {Journal of Cosmology and Astroparticle Physics},

number = 05,

volume = 2015,

place = {United States},

year = {Fri May 08 00:00:00 EDT 2015},

month = {Fri May 08 00:00:00 EDT 2015}

}