Dynamical breaking of shift-symmetry and super-Planckian inflation

Mazumdar, Anupam and Noumi, Toshifumi and Yamaguchi, Masahide (2014) Dynamical breaking of shift-symmetry and super-Planckian inflation. Physical Review D, 90. ISSN 1550-7998

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Shift-symmetry is essential to protect the flatness of the potential, even beyond the super-Planckian vacuum expectation value (VEV) for an inflaton field. The breaking of the shift-symmetry can yield potentials suitable for super-Planckian excursion of the inflaton. The aim of this paper is to illustrate that it is indeed possible to break the shift-symmetry dynamically within 4 dimensional supergravity prior to a long phase of inflation. Thanks to the shift-symmetry, the leading contribution to the inflaton potential is free from the dangerous exponential factor even after its breaking, which is the main obstacle to realizing the super-Planckian inflation in supergravity. But, unfortunately, in a simple model, the potential obtained for the inflaton would be cosine type potential rather than power-law one and it is difficult to realize a super-Planckian breaking scale.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review D
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© 2014 American Physical Society
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Deposited On:
01 Sep 2014 08:55
Last Modified:
19 Sep 2023 01:16