- 1475-7516_2015_01_018
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**A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio.** / McDonald, John.

Research output: Contribution to journal › Journal article › peer-review

McDonald, J 2015, 'A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio', *Journal of Cosmology and Astroparticle Physics*, vol. 2015, no. 1, 018. https://doi.org/10.1088/1475-7516/2015/01/018

McDonald, J. (2015). A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio. *Journal of Cosmology and Astroparticle Physics*, *2015*(1), [018]. https://doi.org/10.1088/1475-7516/2015/01/018

McDonald J. A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio. Journal of Cosmology and Astroparticle Physics. 2015 Jan;2015(1). 018. https://doi.org/10.1088/1475-7516/2015/01/018

@article{6f3fc11a8e624c61b9f9e6461294af8a,

title = "A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio",

abstract = "We present a minimal axion inflation model which can generate a large tensor-to-scalar ratio while remaining sub-Planckian. The modulus of a complex scalar field Phi with a lambda vertical bar Phi vertical bar(4) potential couples directly to the gauge field of a strongly-coupled sector via a term of the form (vertical bar Phi vertical bar/M-Pl)(m) F (F) over tilde . This generates a minimum of the potential which is aperiodic in the phase. The resulting inflation model is equivalent to a phi(4/(m+1)) chaotic inflation model. For the natural case of a leading-order portal-like interaction of the form Phi dagger Phi F (F) over tilde, the model is equivalent to a phi(4/3) chaotic inflation model and predicts a tensor-to-scalar ratio r = 16/3N = 0.097 and a scalar spectral index n(s) = 1 - 5/3N = 0.970 . The value of vertical bar Phi vertical bar remains sub-Planckian throughout the observable era of inflation, with vertical bar Phi vertical bar less than or similar to 0.01M(Pl) for N less than or similar to 60 when lambda similar to 1.",

keywords = "inflaiion, physics of the early universe, CHAOTIC INFLATION, CP INVARIANCE, SUPERGRAVITY",

author = "John McDonald",

note = "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. ",

year = "2015",

month = jan,

doi = "10.1088/1475-7516/2015/01/018",

language = "English",

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journal = "Journal of Cosmology and Astroparticle Physics",

issn = "1475-7516",

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T1 - A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio

AU - McDonald, John

N1 - 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.

PY - 2015/1

Y1 - 2015/1

N2 - We present a minimal axion inflation model which can generate a large tensor-to-scalar ratio while remaining sub-Planckian. The modulus of a complex scalar field Phi with a lambda vertical bar Phi vertical bar(4) potential couples directly to the gauge field of a strongly-coupled sector via a term of the form (vertical bar Phi vertical bar/M-Pl)(m) F (F) over tilde . This generates a minimum of the potential which is aperiodic in the phase. The resulting inflation model is equivalent to a phi(4/(m+1)) chaotic inflation model. For the natural case of a leading-order portal-like interaction of the form Phi dagger Phi F (F) over tilde, the model is equivalent to a phi(4/3) chaotic inflation model and predicts a tensor-to-scalar ratio r = 16/3N = 0.097 and a scalar spectral index n(s) = 1 - 5/3N = 0.970 . The value of vertical bar Phi vertical bar remains sub-Planckian throughout the observable era of inflation, with vertical bar Phi vertical bar less than or similar to 0.01M(Pl) for N less than or similar to 60 when lambda similar to 1.

AB - We present a minimal axion inflation model which can generate a large tensor-to-scalar ratio while remaining sub-Planckian. The modulus of a complex scalar field Phi with a lambda vertical bar Phi vertical bar(4) potential couples directly to the gauge field of a strongly-coupled sector via a term of the form (vertical bar Phi vertical bar/M-Pl)(m) F (F) over tilde . This generates a minimum of the potential which is aperiodic in the phase. The resulting inflation model is equivalent to a phi(4/(m+1)) chaotic inflation model. For the natural case of a leading-order portal-like interaction of the form Phi dagger Phi F (F) over tilde, the model is equivalent to a phi(4/3) chaotic inflation model and predicts a tensor-to-scalar ratio r = 16/3N = 0.097 and a scalar spectral index n(s) = 1 - 5/3N = 0.970 . The value of vertical bar Phi vertical bar remains sub-Planckian throughout the observable era of inflation, with vertical bar Phi vertical bar less than or similar to 0.01M(Pl) for N less than or similar to 60 when lambda similar to 1.

KW - inflaiion

KW - physics of the early universe

KW - CHAOTIC INFLATION

KW - CP INVARIANCE

KW - SUPERGRAVITY

U2 - 10.1088/1475-7516/2015/01/018

DO - 10.1088/1475-7516/2015/01/018

M3 - Journal article

VL - 2015

JO - Journal of Cosmology and Astroparticle Physics

JF - Journal of Cosmology and Astroparticle Physics

SN - 1475-7516

IS - 1

M1 - 018

ER -