Related papers: CMB Cold Spot from Inflationary Feature Scattering
In a recently proposed approach to testing models of inflation by Cosmic Microwave Background (CMB) radiation the reheating temperature is directly expressed in terms of the CMB observables. Its model independent bounds translate in a given…
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 solution describing this feature \cite{minu}…
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…
We investigate the cosmic variance of the skewness of the cosmic microwave background (CMB) anisotropies in an inflationary model which leads to the baryon isocurvature scenario for the cosmic structure formation. In this model, the baryon…
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…
Cosmological $\alpha$-attractors stand out as particularly compelling models to describe inflation in the very early universe, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate…
We study single-field inflationary models with steep step-like features in the potential that lead to the temporary violation of the slow-roll conditions during the evolution of the inflaton. These features enhance the power spectrum of the…
Understanding the properties of dark matter has proved to be one of the most challenging problems of particle phenomenology. In this paper, we have tried to understand the phenomenology of dark matter in light of very well understood…
We consider the prospects of probing features in the primordial power spectrum with future Cosmic Microwave Background (CMB) polarization measurements. In the scope of the inflationary scenario, such features in the spectrum can be produced…
We point out that the temperature fluctuations of cosmic microwave background (CMB) can be generated in a way that is different from the one usually assumed in slow-roll inflation. Our mechanism is based on vacuum fluctuations of fields…
A thorough MCMC analysis of any inflationary model against the current cosmological data is essential for assessing the validity of such a model as a viable inflationary model. Warm Inflation, producing both thermal and quantum…
We revisit the Cosmic Microwave Background (CMB) constraints on the spatial curvature of the Universe, assessing how they change when the curvature parameter and the primordial inflationary scalar spectrum are treated consistently within…
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 describe new scenarios of generating curvature perturbations when inflaton (curvaton) has significant interactions. We consider a ``spot'', which arises from interactions associated with enhanced symmetric point (ESP) on the trajectory.…
Inflation creates perturbations for the large scale structures in the universe, but it also dilutes everything. Therefore it is pertinent that the end of inflation must explain how to excite the Standard Model {\it dof} along with the dark…
We investigate the formation of large peaks in the inflationary curvature power spectrum from double-well potentials. In such scenarios, the initial CMB spectrum is created at large field values. Subsequently, the inflaton will cross one of…
The upcoming satellite missions MAP and Planck will measure the spectrum of fluctuations in the Cosmic Microwave Background with unprecedented accuracy. We discuss the prospect of using these observations to distinguish among proposed…
We conduct a model-independent analysis of temporal features during inflation in the large-scale CMB temperature power spectrum allowing for the possibility of non-negligible tensor contributions. Of 20 principal components of the…
If inflation was preceded by a radiation era then at the time of inflation there will exist a decoupled thermal distribution of gravitons. Gravitational waves generated during inflation will be amplified by the process of stimulated…
We develop a variant of the generalized slow roll approach for calculating the curvature power spectrum that is well-suited for order unity deviations in power caused by sharp features in the inflaton potential. As an example, we show that…