Related papers: Possibly Large Corrections to the Inflationary Obs…
The observed power spectrum of the cosmic microwave background (CMB) is consistent with inflationary cosmology, which predicts a nearly scale-invariant power spectrum of quantum fluctuations of the inflaton field as they exit the Hubble…
We investigate observational constraints on inflationary parameters in the context of an holographic cosmology with an induced gravity correction. We consider two situations where a universe is firstly filled with a scalar field and…
Massive fields during inflation provide an interesting opportunity to test new physics at very high energy scales. Meanwhile in fundamental realizations, the inflationary field space typically has a curved geometry, which may leave…
There is a duality in the observables $n_s$, $r$ and the inflaton potential between large and small $\eta_H$ for the constant-roll inflation if the slow-roll parameter $\epsilon_H$ is negligible. In general, the duality between $\eta_H$ and…
The recent progress in embedding inflation in string theory has made it clear that the problem of moduli stabilization cannot be ignored in this context. In many models a special role is played by the volume modulus, which is modified in…
Extending our previous work on the robustness of inflation to perturbations in the scalar field, we investigate the effects of perturbations in the transverse traceless part of the extrinsic curvature on the evolution of an inhomogeneous…
We study the back-reaction of moduli fields on the inflaton potential in generic models of F-term inflation. We derive the moduli corrections as a power series in the ratio of Hubble scale and modulus mass. The general result is illustrated…
Cosmological perturbations of massive higher-spin fields are generated during inflation, but they decay on scales larger than the Hubble radius as a consequence of the Higuchi bound. By introducing suitable couplings to the inflaton field,…
There is a widespread belief among inflationary cosmologists that a local observer cannot sense super-horizon gravitons. The argument goes that a local observer would subsume super-horizon gravitons into a redefinition of his coordinate…
Coupling between sub- and super-Hubble modes can affect the locally observed statistics of our universe. In the context of Quasi-Single Field Inflation, we can compute correlation functions and derive the influence of those unobservable…
The simplicity of the CMB data, so well described by single-field inflation, raises the question whether there might be an equally simple multi-field realization consistent with the observations. We explore the idea that an approximate…
Strongly non-geodesic, or rapidly turning trajectories in multifield inflation have attracted much interest recently from both theoretical and phenomenological perspectives. Most models with large turning rates in the literature are…
Modular inflation is the restriction to two fields of automorphic inflation, a general group based framework for multifield scalar field theories with curved target spaces, which can be parametrized by the comoving curvature perturbation…
Predictions of inflationary schemes can be influenced by the presence of extra dimensions. This could be of particular relevance for the spectrum of gravitational waves in models where the extra dimensions provide a brane-world solution to…
In the framework of gravitational models obtained from the Geometric Inflation's proposal, where an infinite tower of curvature scalars are included into the action, we compute the slow-roll parameters by the Hubble slow-roll approach. We…
Inflation with a scalar-field potential of the form \lambda (\phi^2-v^2)^2 can be described in terms of a parametrical attractor with critical points, whose driftage depends on the control value of the slowly changing Hubble rate. The…
We point out that if quantum field renormalization is taken into account the predictions of slow-roll inflation for both the scalar and tensorial power spectra change significantly for wavelengths that today are at observable scales
We consider the effects of fields with suddenly changing mass on the inflationary power spectra. In this context, when a field becomes light, it will be excited. This process contributes to the tensor power spectrum. We compute these…
Employing an effective field theory approach to inflationary perturbations, we analyze in detail the effect of curvature-generated Lagrangian operators on various observables, focusing on their running with scales. At quadratic order, we…
The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…