Related papers: Exploring Inflationary Initial State With Large Sc…
We investigate the possibility that the inflationary period in the early universe was preceded by a primordial stage of strong anisotropy. In particular we focus on the simplest model of this kind, where the spacetime is described by a…
A model-independent determination of the primordial power spectrum of matter density fluctuations could uniquely probe physics of the very early universe, and provide powerful constraints on inflationary models. We parametrize the…
The current available CMB data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l < 40). This lack of power is not explained by the minimal LCDM model, and one of the possible mechanisms explored in…
Perturbations from inflation evolve into large scale structure of the late universe, and encode abundant cosmic structure formation physics. We allow freedom in the primordial power spectrum, rather than assuming a power law scale…
We study quintessential inflation using a generalized exponential potential $V(\phi)\propto exp(-\lambda \phi^n/Mpl^n), n>1$, the model admits slow-roll inflation at early times and leads to close-to-scaling behaviour in the post…
We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly…
The inflationary paradigm provides a robust description of the peculiar initial conditions which are required for the success of the Hot Big Bang model of cosmology, as well as of the recent precision measurements of temperature…
Recently researchers have been studying various conditions as swampland criteria in cosmological implications. They have studied many inflation models with different swampland conditions. Occasionally these conjectures are modified and lead…
We discuss structure formation in models with a spectator field in small-field inflation which accommodate a secondary period of inflation. In such models, subgalactic scale primordial fluctuations can be much suppressed in comparison to…
We consider the effects on the primordial power spectrum of a period of radiation-dominated expansion prior to the inflationary era. If inflation lasts a total of only 60 e-folds or so, the boundary condition for quantum modes cannot be…
Recently, it was proposed that a small true vacuum universe can inflate spontaneously, in principle. Furthermore, there should be matter creation in vacuum inflation due to quantum fluctuations, and the matter created will influence the…
We present the constraints on inflationary parameters in a flat $\Lambda$CDM universe obtained by WMAP three year data release, plus smaller scale CMB and two LSS data sets, 2dF and SDSS (treated separately). We use a Markov Chain Monte…
Various scenarios of cosmic inflation enhance the amplitude of the stochastic gravitational wave background (SGWB) at frequencies detectable by the LISA detector. We develop tools for a template-based analysis of the SGWB and introduce a…
We investigate the entanglement due to geometric corrections in particle creation during inflation. To do so, we propose a single-field inflationary scenario, nonminimally coupled to the scalar curvature of spacetime. We require particle…
The detection of a primordial stochastic gravitational wave background has the potential to reveal unprecedented insights into the early universe, and possibly into the dynamics of inflation. Generically, UV-complete inflationary models…
(Abridged) We study dissipative inflation in the regime where the dissipative term takes a specific form, \Gamma=\Gamma(\phi), analyzing two models in the weak and strong dissipative regimes with a SUSY breaking potential. After developing…
One of the characteristics of the "Matter Bounce" scenario, an alternative to cosmological inflation for producing a scale-invariant spectrum of primordial adiabatic fluctuations on large scales, is a break in the power spectrum at a…
We revisit an inflationary scenario in which primordial inhomogeneities arise from a quantum collapse, a stochastic mechanism described in the context of quantum collapse theories in its continuous version and within semiclassical gravity.…
The initial condition problem of inflation is examined from the perspective of both spacetime embedding and scalar field dynamics. The spacetime embedding problem is solved for arbitrary initial spatial curvature Omega, which generalizes…
According to the Borde-Guth-Vilenkin (BGV) theorem an expanding region of spacetime cannot be extended to the past beyond some boundary \mathcal{B}. Therefore, the inflationary universe must have had some kind of beginning. However, the BGW…