Related papers: Power law $\alpha$-Starobinsky inflation
We investigate how inflation model selection is affected by the presence of additional free-streaming relativistic degrees of freedom, i.e. dark radiation. We perform a full Bayesian analysis of both inflation parameters and cosmological…
In this paper, we would like to examine whether stable de Sitter inflationary solutions appear within power-law extensions of the Starobinsky model. In particular, we will address general constraints for the existence along with the…
In the recent sixth data release (DR6) of the Atacama Cosmology Telescope (ACT) collaboration, the value of $n_{\rm s}=0.9743 \pm 0.0034$ for the scalar spectral index is reported, which excludes the Starobinsky and Higgs inflationary…
Thanks to the Planck Collaboration, we know the value of the scalar spectral index of primordial fluctuations with unprecedented precision. In addition, the joint analysis of the data from Planck, BICEP2, and KEK has further constrained the…
The latest CMB data from ACT DR6, combined with Planck, DESI, and BICEP/Keck, indicate a slight upward shift in the scalar spectral index, placing several previously favored inflationary models under tension. We study an inflationary…
We investigate inflation in closed Friedmann-Robertson-Walker universe filled with the scalar field with power-law potential. For a wide range of powers and parameters of the potential we numerically calculated the slow-roll parameters and…
We construct a new model of quintessential $\alpha$ attractor inflation in conjunction with the features of non-oscillating early dark energy (EDE). Slow-roll plateau of this model is obtained, and analyzed in $k$-space, through the…
We point out that in the large field regime, the recently proposed superconformal D-term inflation model coincides with the Starobinsky model. In this regime, the inflaton field dominates over the Planck mass in the gravitational kinetic…
The constraints on a general form of the power-law potential and the dissipation coefficient in the framework of warm single field inflation imposed by Planck data will be investigated. {By Considering a quasi-static Universe, besides a…
We consider the ghost-free higher order corrections to the Starobinsky model in the old minimal supergravity. In general, higher order corrections cannot be forbidden by symmetries, which likely violate the flatness of the scalaron…
The generation of a baryon-antibaryon asymmetry in the Universe via gravitational baryogenesis is investigated for two f(R) modified theories of gravity, the widely used Starobinsky $f(R)=R+R^{2}/M^{2}$ model, and the recently proposed…
(Shortened abstract) While a featureless, nearly scale invariant, primordial scalar power spectrum fits the most recent CMB data rather well, certain features in the spectrum are known to lead to a better fit to the data (although, the…
We study inflation induced by (power-low) scalar curvature corrections to General Relativity. The class of inflationary scalar potentials $V(\sigma)\sim\exp[n\,\sigma]$, $n$ general parameter, is investigated in the Einsein frame and the…
An approach to construct cosmological inflation models on the basis of a certain dependence of the scalar field evolution on the e-folds number is considered. The reconstruction of the model background parameters according to the kind of…
We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic…
We discuss the soundness of inflationary scenarios in theories beyond the Starobinsky model, namely a class of theories described by arbitrary functions of the Ricci scalar and the K-essence field. We discuss the pathologies associated with…
We generalize Ringstr\"om's global future causal stability results (Ringstr\"om 2009) for certain expanding cosmological solutions of the Einstein-scalar field equations to solutions of the Einstein-Maxwell-scalar field system. In…
We investigate the modifications to inflationary observables that arise when adopting an $\alpha$-vacuum instead of the standard Bunch--Davies vacuum for quantum fluctuations during inflation. Within the Starobinsky inflationary model, we…
In this paper we will discuss a new model for inflation based on topological ideas. For that purpose we will consider the change of the topology of the spatial component seen as compact 3-manifold. We analyzed the topology change by using…
The Starobinsky model is a natural inflationary scenario in which inflation arises due to quantum effects of the massless matter fields. A modified version of the Starobinsky (MSt) model takes the masses of matter fields and the…