An alternative framework for E-model inflation in supergravity

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 Kahler potentials K-1 and (K) over tilde (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 super-field 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)over tilde>(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.

Automated summary

We propose novel realizations of E-model inflation within Supergravity, where the existence of a pole in the kinetic term of the inflaton superfield is crucial. By tuning the coefficients of the superpotential, inflation can be achieved under certain conditions, and a prediction for the tensor-to-scalar ratio is made.