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Non-Gaussianity from Axion Monodromy Inflation
We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has recently been proposed as a possible realization of chaotic inflati...
Autores principales: | , , , |
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Lenguaje: | eng |
Publicado: |
2009
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Materias: | |
Acceso en línea: | https://dx.doi.org/10.1088/1475-7516/2010/06/001 http://cds.cern.ch/record/1229684 |
_version_ | 1780918466663940096 |
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author | Hannestad, Steen Haugbolle, Troels Jarnhus, Philip R. Sloth, Martin S. |
author_facet | Hannestad, Steen Haugbolle, Troels Jarnhus, Philip R. Sloth, Martin S. |
author_sort | Hannestad, Steen |
collection | CERN |
description | We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has recently been proposed as a possible realization of chaotic inflation in string theory, where the monodromy from wrapped branes extends the range of the closed string axions to beyond the Planck scale. The superimposed oscillations in the potential can lead to new signatures in the CMB spectrum and bispectrum. In particular the bispectrum will have a new distinct shape. We calculate the power spectrum and bispectrum of curvature perturbations in the model, as well as make analytic estimates in various limiting cases. From the numerical analysis we find that for a wide range of allowed parameters the model produces a feature in the bispectrum with fnl ~ 50 or larger while the power spectrum is almost featureless. This model is therefore an example of a string-inspired inflationary model which is testable mainly through its non-Gaussian features. Finally we provide a simple analytic fitting formula for the bispectrum which is accurate to approximately 5% in all cases, and easily implementable in codes designed to provide non-Gaussian templates for CMB analyses. |
id | cern-1229684 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2009 |
record_format | invenio |
spelling | cern-12296842023-03-12T05:19:44Zdoi:10.1088/1475-7516/2010/06/001http://cds.cern.ch/record/1229684engHannestad, SteenHaugbolle, TroelsJarnhus, Philip R.Sloth, Martin S.Non-Gaussianity from Axion Monodromy InflationParticle Physics - PhenomenologyWe study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has recently been proposed as a possible realization of chaotic inflation in string theory, where the monodromy from wrapped branes extends the range of the closed string axions to beyond the Planck scale. The superimposed oscillations in the potential can lead to new signatures in the CMB spectrum and bispectrum. In particular the bispectrum will have a new distinct shape. We calculate the power spectrum and bispectrum of curvature perturbations in the model, as well as make analytic estimates in various limiting cases. From the numerical analysis we find that for a wide range of allowed parameters the model produces a feature in the bispectrum with fnl ~ 50 or larger while the power spectrum is almost featureless. This model is therefore an example of a string-inspired inflationary model which is testable mainly through its non-Gaussian features. Finally we provide a simple analytic fitting formula for the bispectrum which is accurate to approximately 5% in all cases, and easily implementable in codes designed to provide non-Gaussian templates for CMB analyses.We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has recently been proposed as a possible realization of chaotic inflation in string theory, where the monodromy from wrapped branes extends the range of the closed string axions to beyond the Planck scale. The superimposed oscillations in the potential can lead to new signatures in the CMB spectrum and bispectrum. In particular the bispectrum will have a new distinct shape. We calculate the power spectrum and bispectrum of curvature perturbations in the model, as well as make analytic estimates in various limiting cases. From the numerical analysis we find that for a wide range of allowed parameters the model produces a feature in the bispectrum with fnl ~ 50 or larger while the power spectrum is almost featureless. This model is therefore an example of a string-inspired inflationary model which is testable mainly through its non-Gaussian features. Finally we provide a simple analytic fitting formula for the bispectrum which is accurate to approximately 5% in all cases, and easily implementable in codes designed to provide non-Gaussian templates for CMB analyses.arXiv:0912.3527CERN-PH-TH-2009-253CERN-PH-TH-2009-253oai:cds.cern.ch:12296842009-12-21 |
spellingShingle | Particle Physics - Phenomenology Hannestad, Steen Haugbolle, Troels Jarnhus, Philip R. Sloth, Martin S. Non-Gaussianity from Axion Monodromy Inflation |
title | Non-Gaussianity from Axion Monodromy Inflation |
title_full | Non-Gaussianity from Axion Monodromy Inflation |
title_fullStr | Non-Gaussianity from Axion Monodromy Inflation |
title_full_unstemmed | Non-Gaussianity from Axion Monodromy Inflation |
title_short | Non-Gaussianity from Axion Monodromy Inflation |
title_sort | non-gaussianity from axion monodromy inflation |
topic | Particle Physics - Phenomenology |
url | https://dx.doi.org/10.1088/1475-7516/2010/06/001 http://cds.cern.ch/record/1229684 |
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