相关论文: Noncommutative chaotic inflation and WMAP three ye…
Recent Planck data show the anomalies of CMB fluctuations on large angular scales, which confirms the early observations by WMAP. We continue studying an inflationary model, in which before the slow roll inflation the universe is in a…
We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial…
The "central" region of moduli space of M- and string theories is where the string coupling is about unity and the volume of compact dimensions is about the string volume. Here we argue that in this region the non-perturbative potential…
We use the most recent cosmic microwave background (CMB) data to perform a Bayesian statistical analysis and discuss the observational viability of inflationary models with a non-minimal coupling,~$\xi$, between the inflaton field and the…
We constrain spatially-flat tilted and nonflat untilted scalar field ($\phi$) dynamical dark energy inflation ($\phi$CDM) models by using Planck 2015 cosmic microwave background (CMB) anisotropy measurements and recent baryonic acoustic…
Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years.…
Assuming the space dimension is not constant but decreases during the expansion of the Universe, we study chaotic inflation with the potential $m^2 \phi^2/2$. We write down field equations in the slow-roll approximation and define slow…
The angular power spectrum of the cosmic microwave background temperature anisotropy observed by WMAP has an anomalous dip at l~20 and bump at l~40. One explanation for this structure is the presence of features in the primordial curvature…
We constrain models of single field inflation with the pre-\textit{Planck} CMB data. The data used here is the 9-year Wilkinson Microwave Anisotropy Probe (\textit{WMAP}) data, South Pole Telescope (SPT) data and Atacama Cosmology Telescope…
We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has…
The inflationary cosmology paradigm is very successful in explaining the CMB anisotropy to the percent level. Besides the dependence on the inflationary model, the power spectra, spectral tilt and non-Gaussianity of the CMB temperature…
In arXiv:0908.4089, we have proposed a model where natural inflation is realized on a steep potential as a consequence of the interaction of the inflaton with gauge fields through an axion-like coupling. In the present work we study the…
The non-Gaussianity of inflationary perturbations, as encoded in the bispectrum (or 3-point correlator), has become an important additional way of distinguishing between inflation models, going beyond the linear Gaussian perturbation…
In this paper we discuss the inflationary universe in the context of a Chaplygin gas equation of state within the framework of the effective theory of loop quantum cosmology. Under the slow-roll approximation, we calculate the primordial…
We propose an inflation model in supergravity, in which chaotic and hybrid inflation occurs successively, followed by new inflation. During hybrid inflation, adiabatic fluctuations with a running spectral index with $\ns >1$ on a large…
In inflation cosmologies, cosmic structure develops through the gravitational instability of the inevitable quantum noise in primordial scalar fields. I show how the acceleration of the universe defines the shape of the primordial spectrum…
Conventional wisdom says that a chaotic inflation model with a power-law potential is ruled out by the recent Planck-BICEP/Keck results. We find, however, that the model can be assisted by a non-minimally coupled scalar field and still…
The first-year WMAP data, in combination with any one of a number of other cosmic probes, show that we live in a flat \Lambda-dominated CDM universe with \Omega_m ~ 0.27 and \Omega_\Lambda ~ 0.73. In this model the late-time action of the…
We show that a certain class of short-distance cutoff can give rise to large suppression on the CMB anisotropies at large angular scales.
We forecast the ability of cosmic microwave background (CMB) temperature and polarization datasets to constrain theories of eternal inflation using cosmic bubble collisions. Using the Fisher matrix formalism, we determine both the overall…