Year: 2016
Type: article
Abstract: Working in the Large Volume Scenario (LVS) of IIB Calabi-Yau flux compactifications, we construct inflationary models from recently computed higher derivative (α') 3 -corrections. Inflation is driven by a Kähler modulus whose potential arises from the aforementioned corrections, while we use the inclusion of string loop effects just to ensure the existence of a graceful exit when necessary. The effective inflaton potential takes a Starobinsky-type form V = V 0 (1− e −νϕ ) 2 , where we obtain one set-up with ν=−1/√3 and one with ν=2/√3 corresponding to inflation occurring for increasing or decreasing ϕ respectively. The inflationary observables are thus in perfect agreement with PLANCK, while the two scenarios remain observationally distinguishable via slightly varying predictions for the tensor-to-scalar ratio r . Both set-ups yield r ≃ (2... 7) × 10 −3 . They hence realise inflation with moderately large fields (Δϕ∼ 6 M Pl ) without saturating the Lyth bound. Control over higher corrections relies in part on tuning underlying microscopic parameters, and in part on intrinsic suppressions. The intrinsic part of control arises as a leftover from an approximate effective shift symmetry at parametrically large volume.
Authors: Benedict J. Broy, David Ciupke, Francisco G. Pedro, Alexander Westphal
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,290
OpenAlex ID: W2203386637