Running spectral index from large-field inflation with modulations revisited

  title={Running spectral index from large-field inflation with modulations revisited},
  author={Michael Czerny and Takeshi Kobayashi and Fuminobu Takahashi},
  journal={Physics Letters B},

Figures from this paper

Simple single field inflation models and the running of spectral index

The BICEP2 experiment confirms the existence of primordial gravitational wave with the tensor-to-scalar ratio r = 0 ruled out at 7σ level. The consistency of this large value of r with the Planck

Axion monodromy inflation with multi-natural modulations

We study parameter space in the axion monodromy inflation corrected by dynamically generated terms involving with the axion. The potential has the linear term with multiple sinusoidal functions,

Beginning of Universe through large field hybrid inflation

Recent detection of B-mode polarization induced from tensor perturbations by the BICEP2 experiment implies the so-called large field inflation, where an inflaton field takes super-Planckian

Natural inflation with and without modulations in type IIB string theory

A bstractWe propose a mechanism for the natural inflation with and without modulation in the framework of type IIB string theory on toroidal orientifold or orbifold. We explicitly construct the

Ambiguity in running spectral index with an extra light field during inflation

At the beginning of inflation there could be extra dynamical scalar fields that will soon disappear (become static) before the end of inflation. In the light of multi-field inflation, those extra

Multi-natural inflation in supergravity

A bstractWe show that the recently proposed multi-natural inflation can be realized within the framework of 4D $ \mathcal{N} $ = 1 supergravity. The inflaton potential mainly consists of two

Multi-natural inflation

Quartic potential inspired warm standard and tachyon scalar fields brane-world inflation

It is observed that the ranges of the results of tensor-to-scalar ratio, scalar spectral index and running of spectral favor observational data like BICEP2, WMAP9 and Planck.

Symmetry Breaking Indication for Supergravity Inflation in Light of the Planck 2015

Supergravity (SUGRA) theories with exact global U(1) symmetry or shift symmetry in Kähler potential provide natural frameworks for inflation. However, quadratic inflation is disfavoured by the new



Running of the scalar spectral index from inflationary models

The scalar spectral index n is an important parameter describing the nature of primordial density perturbations. Recent data, including those from the Wilkinson Microwave Anisotropy Probe satellite,

Running Spectral Index from Inflation with Modulations

We argue that a large negative running spectral index, if confirmed, might suggest that there are abundant structures in the inflaton potential, which result in a fairly large (both positive and

The spectral index and its running in axionic curvaton

We show that a sizable running spectral index suggested by the recent SPT data can be explained in the axionic curvaton model with a potential that consists of two sinusoidal contributions of

Multi-natural inflation in supergravity

A bstractWe show that the recently proposed multi-natural inflation can be realized within the framework of 4D $ \mathcal{N} $ = 1 supergravity. The inflaton potential mainly consists of two

New Universal Local Feature in the Inflationary Perturbation Spectrum

A model is developed in which the inflaton potential experiences a sudden small change in its second derivative (the effective mass of the inflaton). An exact treatment demonstrates that the

Is a step in the primordial spectral index favoured by CMB data

A sudden small change in the second derivative of the inflaton potential can result in a universal local feature in the spectrum of primordial perturbations generated during inflation. The exact

Running kinetic inflation

We study a recently proposed running kinetic inflation model in which the inflaton potential becomes flat due to rapid growth of the kinetic term at large inflaton field values. As concrete examples,

Multi-natural inflation

Polynomial chaotic inflation in supergravity

We present a general polynomial chaotic inflation model in supergravity, for which the predicted spectral index and tensor-to-scalar ratio can lie within the 1σ region allowed by the Planck results.