相关论文: Pre-inflation models and WMAP data

We assay how inflationary models whose properties are dominated by the dynamics of a single scalar field are constrained by cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP). We classify…

Recent experimental determinations of the spectral index describing the scalar mode spectrum of density perturbations encourage comparison with predictions from models of the very early universe. Unlike extended inflation, Induced-gravity…

We confront predictions of inflationary scenarios with the WMAP data, in combination with complementary small-scale CMB measurements and large-scale structure data. The WMAP detection of a large-angle anti-correlation in the…

Recent combined results from the Wilkinson Microwave Anisotropy Probe (WMAP) and Sloan Digital Sky Survey (SDSS) provide a remarkable set of data which requires more accurate and general investigation. Here we derive formulae for the power…

We carry out numerical investigations of the perturbations in Nflation models where the mass spectrum is generated by random matrix theory. The tensor-to-scalar ratio and non-gaussianity are already known to take the single-field values,…

The vacuum inflation with a boundary condition specified at a short-distance scale in a generally primeval non-flat Universe, and implications of the correspondingly modified primordial power spectrum via the WMAP data are investigated. We…

The enormous red-shifting of the modes during the inflationary epoch suggests that physics at the very high energy scales may modify the primordial perturbation spectrum. Therefore, the measurements of the anisotropies in the Cosmic…

The Wilkinson Microwave Anisotropy Probe microwave background data suggest that the primordial spectrum of scalar curvature fluctuations is suppressed at small wavenumbers. We propose a UV/IR mixing effect in small-field inflationary models…

The Wilkinson Microwave Anisotropy Probe microwave background data may be giving us clues about new physics at the transition from a ``stringy'' epoch of the universe to the standard Friedmann Robertson Walker description. Deviations on…

Recent results from the Wilkinson Microwave Anisotropy Probe have been called a corroboration, or even a confirmation, of inflation. Yet, the results include features that require, at least, a significant distortion of what is usually meant…

Recent fits of cosmological parameters by the first year Wilkinson Microwave Anisotropy Probe (WMAP) measurement seem to favor a primordial scalar spectrum with a large varying index from blue to red. We use the inflationary flow equations…

A fundamental prediction of inflation is a nearly scale-invariant spectrum of gravitational wave. The features of such a signal provide extremely important information about the physics of the early universe. In this paper, we focus on…

The new three year WMAP data seem to confirm the presence of non-standard large scale features in the Cosmic Microwave Anisotropies power spectrum. While these features may hint at uncorrected experimental systematics, it is also possible…

In bounce inflation scenario, the inflation is singularity-free, while the advantages of inflation are reserved. We analytically calculate the power spectrum of its primordial gravitational waves (GWs), and show a universal result including…

This article investigates the predictions of an inflationary phase starting from a homogeneous and anisotropic universe of the Bianchi I type. After discussing the evolution of the background spacetime, focusing on the number of e-folds and…

Formulae are derived for the spectra of scalar curvature perturbations and gravitational waves produced during inflation, special cases of which include power law inflation, natural inflation in the small angle approximation and inflation…

Using a large N sigma model approximation we explicitly calculate the power spectrum of gravitational waves arising from a global phase transition in the early universe and we confirm that it is scale invariant, implying an observation of…

For the original hybrid inflation model, we calculate the power spectrum of curvature perturbations generated during the waterfall, taking into account the contribution of entropic modes. We study the regime where the potential is very…

Inflation may provide unique insight into the physics at the highest available energy scales that cannot be replicated in any realistic terrestrial experiment. Features in the primordial power spectrum are generically predicted in a wide…

We investigate the scalar perturbation produced at the pre-inflationary stage driven by a massive scalar field in Eddington-inspired Born-Infeld gravity. The scalar power spectrum exhibits a peculiar rise for low $k$-modes. The…