Can CMB data constrain the inflationary field range?
Abstract
We study to what extent the spectral index n{sub s} and the tensortoscalar ratio r determine the field excursion Δφ during inflation. We analyse the possible degeneracy of Δ φ by comparing three broad classes of inflationary models, with different dependence on the number of efoldings N, to benchmark models of chaotic inflation with monomial potentials. The classes discussed cover a large set of inflationary single field models. We find that the field range is not uniquely determined for any value of (n{sub s}, r); one can have the same predictions as chaotic inflation and a very different Δ φ. Intriguingly, we find that the field range cannot exceed an upper bound that appears in different classes of models. Finally, Δ φ can even become subPlanckian, but this requires to go beyond the singlefield slowroll paradigm.
 Authors:
 Instituto de Física Teórica IFTUAMCSIC, Universidad Autónoma de Madrid, C/ Nicolás Cabrera 1315, Cantoblanco, 28049 Madrid (Spain)
 Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands)
 Publication Date:
 OSTI Identifier:
 22375901
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 09; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICAL METHODS AND COMPUTING; BENCHMARKS; CHAOS THEORY; COSMOLOGICAL INFLATION; DATA; TENSORS
Citation Formats
GarciaBellido, Juan, Roest, Diederik, Scalisi, Marco, and Zavala, Ivonne, Email: juan.garciabellido@uam.es, Email: d.roest@rug.nl, Email: m.scalisi@rug.nl, Email: e.i.zavala@rug.nl. Can CMB data constrain the inflationary field range?. United States: N. p., 2014.
Web. doi:10.1088/14757516/2014/09/006.
GarciaBellido, Juan, Roest, Diederik, Scalisi, Marco, & Zavala, Ivonne, Email: juan.garciabellido@uam.es, Email: d.roest@rug.nl, Email: m.scalisi@rug.nl, Email: e.i.zavala@rug.nl. Can CMB data constrain the inflationary field range?. United States. doi:10.1088/14757516/2014/09/006.
GarciaBellido, Juan, Roest, Diederik, Scalisi, Marco, and Zavala, Ivonne, Email: juan.garciabellido@uam.es, Email: d.roest@rug.nl, Email: m.scalisi@rug.nl, Email: e.i.zavala@rug.nl. Mon .
"Can CMB data constrain the inflationary field range?". United States.
doi:10.1088/14757516/2014/09/006.
@article{osti_22375901,
title = {Can CMB data constrain the inflationary field range?},
author = {GarciaBellido, Juan and Roest, Diederik and Scalisi, Marco and Zavala, Ivonne, Email: juan.garciabellido@uam.es, Email: d.roest@rug.nl, Email: m.scalisi@rug.nl, Email: e.i.zavala@rug.nl},
abstractNote = {We study to what extent the spectral index n{sub s} and the tensortoscalar ratio r determine the field excursion Δφ during inflation. We analyse the possible degeneracy of Δ φ by comparing three broad classes of inflationary models, with different dependence on the number of efoldings N, to benchmark models of chaotic inflation with monomial potentials. The classes discussed cover a large set of inflationary single field models. We find that the field range is not uniquely determined for any value of (n{sub s}, r); one can have the same predictions as chaotic inflation and a very different Δ φ. Intriguingly, we find that the field range cannot exceed an upper bound that appears in different classes of models. Finally, Δ φ can even become subPlanckian, but this requires to go beyond the singlefield slowroll paradigm.},
doi = {10.1088/14757516/2014/09/006},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 09,
volume = 2014,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}

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