N-flation with hierarchically light axions in string compactifications

Cicoli, Michele; Dutta, Koushik; Maharana, Anshuman

doi:10.1088/1475-7516/2014/08/012

Title: N-flation with hierarchically light axions in string compactifications

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Abstract

We propose a possible embedding of axionic N-flation in type IIB string compactifications where most of the Kähler moduli are stabilised by perturbative effects, and so are hierarchically heavier than the corresponding N>> 1 axions whose collective dynamics drives inflation. This is achieved in the framework of the LARGE Volume Scenario for moduli stabilisation. Our set-up can be used to realise a model of either large field inflation or quintessence, just by varying the volume of the internal space which controls the scale of the axionic potential. Both cases predict a very high scale of supersymmetry breaking. A fully explicit stringy embedding of N-flation would require control over dangerous back-reaction effects due to a large number of species. A viable reheating of the Standard Model degrees of freedom can be achieved after the end of inflation due to the perturbative decay of the N light axions which drive inflation.

Authors:

Cicoli, Michele ^[1]; Dutta, Koushik ^[2]; Maharana, Anshuman ^[3]

Dipartimento di Fisica ed Astronomia, Università di Bologna, via Irnerio 46, 40126 Bologna (Italy)
Theory Division, Saha Institute of Nuclear Physics, 1/AF Salt Lake, Kolkata, 700064 (India)
Harish Chandra Research Intitute, Chattnag Road, Jhunsi, Allahabad, 211019 (India)

Publication Date:: Fri Aug 01 00:00:00 EDT 2014

OSTI Identifier:: 22373416

Resource Type:: Journal Article

Journal Name:: Journal of Cosmology and Astroparticle Physics

Additional Journal Information:: Journal Volume: 2014; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516

Country of Publication:: United States

Language:: English

Subject:: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AXIONS; COMPACTIFICATION; COSMOLOGICAL INFLATION; DECAY; DEGREES OF FREEDOM; NONLUMINOUS MATTER; SPACE; STANDARD MODEL; SYMMETRY BREAKING

Citation Formats


                    Cicoli, Michele, Dutta, Koushik, and Maharana, Anshuman. N-flation with hierarchically light axions in string compactifications.  United States: N. p., 2014. 
        Web.  doi:10.1088/1475-7516/2014/08/012.

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                    Cicoli, Michele, Dutta, Koushik, & Maharana, Anshuman. N-flation with hierarchically light axions in string compactifications.  United States.  https://doi.org/10.1088/1475-7516/2014/08/012

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                    Cicoli, Michele, Dutta, Koushik, and Maharana, Anshuman. 2014.  
        "N-flation with hierarchically light axions in string compactifications".  United States.  https://doi.org/10.1088/1475-7516/2014/08/012.

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@article{osti_22373416,

  title        = {N-flation with hierarchically light axions in string compactifications},

  author       = {Cicoli, Michele and Dutta, Koushik and Maharana, Anshuman},

  abstractNote = {We propose a possible embedding of axionic N-flation in type IIB string compactifications where most of the Kähler moduli are stabilised by perturbative effects, and so are hierarchically heavier than the corresponding N>> 1 axions whose collective dynamics drives inflation. This is achieved in the framework of the LARGE Volume Scenario for moduli stabilisation. Our set-up can be used to realise a model of either large field inflation or quintessence, just by varying the volume of the internal space which controls the scale of the axionic potential. Both cases predict a very high scale of supersymmetry breaking. A fully explicit stringy embedding of N-flation would require control over dangerous back-reaction effects due to a large number of species. A viable reheating of the Standard Model degrees of freedom can be achieved after the end of inflation due to the perturbative decay of the N light axions which drive inflation.},

  doi          = {10.1088/1475-7516/2014/08/012},

  url          = {https://www.osti.gov/biblio/22373416},
  journal      = {Journal of Cosmology and Astroparticle Physics},

  issn         = {1475-7516},

  number       = 08,

  volume       = 2014,

  place        = {United States},

  year         = {Fri Aug 01 00:00:00 EDT 2014},

  month        = {Fri Aug 01 00:00:00 EDT 2014}

}

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