Abstract
Abstract
We discuss inflation models within supersymmetry and supergravity frameworks with a landscape of chiral superfields and one U(1) shift symmetry which is broken by non-perturbative symmetry breaking terms in the superpotential. We label the pseudo scalar component of the chiral fields axions and their real parts saxions. Thus in the models only one combination of axions will be a pseudo-Nambu-Goldstone-boson which will act as the inflaton. The proposed models constitute consistent inflation for the following reasons: the inflation potential arises dynamically with stabilized saxions, the axion decay constant can lie in the sub-Planckian region, and consistency with the Planck data is achieved. The axion landscape consisting of m axion pairs is assumed with the axions in each pair having opposite charges. A fast roll-slow roll splitting mechanism for the axion potential is proposed which is realized with a special choice of the axion basis. In this basis the 2m coupled equations split into 2m − 1 equations which enter in the fast roll and there is one unique linear combination of the 2m fields which controls the slow roll and thus the power spectrum of curvature and tensor perturbations. It is shown that a significant part of the parameter space exists where inflation is successful, i.e., N
pivot = [50, 60], the spectral index n
s
of curvature perturbations, and the ratio r of the power spectrum of tensor perturbations and curvature perturbations, lie in the experimentally allowed regions given by the Planck experiment. Further, it is shown that the model allows for a significant region of the parameter space where the effective axion decay constant can lie in the sub-Planckian domain. An analysis of the tensor spectral index n
t
is also given and the future experimental data which constraints n
t
will further narrow down the parameter space of the proposed inflationary models. Topics of further interest include implications of the model for gravitational waves and non-Gaussianities in the curvature perturbations. Also of interest is embedding of the model in strings which are expected to possess a large axionic landscape.
Publisher
Springer Science and Business Media LLC
Subject
Nuclear and High Energy Physics
Reference111 articles.
1. A.H. Guth, The Inflationary Universe: A Possible Solution to the Horizon and Flatness Problems, Phys. Rev.
D 23 (1981) 347 [INSPIRE].
2. A.A. Starobinsky, A New Type of Isotropic Cosmological Models Without Singularity, Phys. Lett.
B 91 (1980) 99 [INSPIRE].
3. A.D. Linde, A New Inflationary Universe Scenario: A Possible Solution of the Horizon, Flatness, Homogeneity, Isotropy and Primordial Monopole Problems, Phys. Lett.
B 108 (1982) 389 [INSPIRE].
4. A. Albrecht and P.J. Steinhardt, Cosmology for Grand Unified Theories with Radiatively Induced Symmetry Breaking, Phys. Rev. Lett.
48 (1982) 1220 [INSPIRE].
5. K. Sato, First Order Phase Transition of a Vacuum and Expansion of the Universe, Mon. Not. Roy. Astron. Soc.
195 (1981) 467 [INSPIRE].
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献