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We present novel realizations of E-model inflation within Supergravity which are largely associated with the existence of a pole of order one in the kinetic term of the (gauge-singlet) inflaton superfield. This pole arises due to the selected logarithmic Kähler potentials K 1 and K ~ 1 , which parameterize the same hyperbolic manifold with scalar curvature R K = - 2 / N , where (- N) < 0 is the coefficient of a logarithmic term. The associated superpotential W exhibits the same R charge with the inflaton-accompanying superfield and includes all the allowed renormalizable terms. For K = K 1 , inflation can be attained for N = 2 at the cost of some tuning regarding the coefficients of the W terms and predicts a tensor-to-scalar ratio r at the level of 0.001. The tuning can be totally eluded for K = K ~ 1 , which allows for quadratic- and quartic-like models with N values increasing with r and spectral index n s close or even equal to its present central observational value. [ABSTRACT FROM AUTHOR]

We propose a modification of no-scale supergravity models which incorporates sgoldstino stabilization and supersymmetry (SUSY) breaking with a tunable cosmological constant by introducing a Kähler potential which yields a kinetic pole of order one. The resulting scalar potential may develop an inflection point, close to which an inflationary period can be realized for subplanckian field values consistently with the observational data. For central value of the spectral index n s , the necessary tuning is of the order of 10 − 6 , the tensor-to-scalar ratio r is tiny whereas the running of n s , a s , is around − 3 ⋅ 10 − 3. Our proposal is compatible with high-scale SUSY and the results of LHC on the Higgs boson mass. [ABSTRACT FROM AUTHOR]

Motivated by the reported discovery of inflationary gravity waves by the Bicep2 experiment, we propose an inflationary scenario in supergravity, based on the standard superpotential used in hybrid inflation. The new model yields a tensor-to-scalar ratio r ≃ 0.14 and scalar spectral index n s ≃ 0.964 , corresponding to quadratic (chaotic) inflation. The important new ingredients are the high-scale, ( 1.6 – 10 ) ⋅ 10 13 GeV , soft supersymmetry breaking mass for the gauge singlet inflaton field and a shift symmetry imposed on the Kähler potential. The end of inflation is accompanied, as in the earlier hybrid inflation models, by the breaking of a gauge symmetry at ( 1.2 – 7.1 ) ⋅ 10 16 GeV , comparable to the grand-unification scale. [ABSTRACT FROM AUTHOR]

We show that models of chaotic inflation based on the ϕp potential and a linear non-minimal coupling to gravity, fR=1+cRϕ, can be done consistent with data in the context of Supergravity, retaining the perturbative unitarity up to the Planck scale, if we employ logarithmic Kähler potentials with prefactors -p(1+n) or -p(n+1)-1, where -0.035≲n≲0.007 for p=2 or -0.0145≲n≲0.006 for p=4. Focusing, moreover, on a model employing a gauge non-singlet inflaton, we show that a solution to the μ problem of MSSM and baryogenesis via non-thermal leptogenesis can be also accommodated. [ABSTRACT FROM AUTHOR]

Models of induced-gravity inflation are formulated within Supergravity employing as inflaton the Higgs field which leads to a spontaneous breaking of a U(1)B-L symmetry at MGUT=2·1016GeV. We use a renormalizable superpotential, fixed by a U(1) R symmetry, and Kähler potentials which exhibit a quadratic non-minimal coupling to gravity with or without an independent kinetic mixing in the inflaton sector. In both cases we find inflationary solutions of Starobinsky type whereas in the latter case, others (more marginal) which resemble those of linear inflation arise too. In all cases the inflaton mass is predicted to be of the order of 1013GeV. Extending the superpotential of the model with suitable terms, we show how the MSSM μ parameter can be generated. Also, non-thermal leptogenesis can be successfully realized, provided that the gravitino is heavier than about 10TeV. [ABSTRACT FROM AUTHOR]