相关论文: Fine-Tuning Solution for Hybrid Inflation in Dissi…
A chaotic model of the early universe within the framework of the singularity-free solutions of Einstein's equation is suggested. The evolution of our universe at its early stage, starting out as a small domain of the parent universe, is…
In our previous paper, we have proposed a new algorithm to calculate the power spectrum of the curvature perturbations generated in inflationary universe with use of the stochastic approach. Since this algorithm does not need the…
We have studied modulated inflation that generates curvature perturbation from light-field fluctuation. As discussed in previous works, even if the fluctuation of the inflaton itself does not generate the curvature perturbation at the…
While moving down the potential on its classical slow roll trajectory, the inflaton field is subject to quantum jumps, which take it up or down the potential at random. In "stochastic inflation", the impact of these quantum jumps is modeled…
Making use of the primordially isocurvature fluctuations, which are generated in inflationary models with multiple scalar fields, we make a phenomenological model that predicts formation of primordial black holes which can account for the…
Dissipative effects can lead to a friction term in the equation of motion for an inflaton field during the inflationary era. The friction term may be linear and localised, in which case it is described by a dissipation coefficient. The…
We consider models of inflation with U(1) gauge fields and charged scalar fields including symmetry breaking potential, chaotic inflation and hybrid inflation. We show that there exist attractor solutions where the anisotropies produced…
Yes, if the universe has compact topology. Inflation is currently the most elegant explanation of why the universe is old, large, nearly flat, homogeneous on large scales and structured on small scales. One of the weaknesses of the…
We investigate the dynamics of the perturbations of the inflaton scalar field oscillating around a minimum of its effective potential in an expanding universe. With the assumption of smallness of the ratio of the Hubble parameter to the…
In this paper we describe the rescattering process in optical field ionization through a one-dimensional model, which improves the well-known quasistatic model by adding the smoothed Coulomb potential in its second step. The above-threshold…
The phase ordering dynamics of coupled chaotic maps on fractal networks are investigated. The statistical properties of the systems are characterized by means of the persistence probability of equivalent spin variables that define the…
We have studied the preheating phase for a class of plateau inflationary model considering the four-legs interaction term $(1/2)g^2\phi^2\chi^2$ between the inflaton $(\phi)$ and reheating field $(\chi)$. We specifically focus on the…
Dynamics of the inflaton is studied when it interacts with boson and fermion fields and in minimal supersymmetric models. This encompasses multifield inflation models, such as hybrid inflation, and typical reheating models. For much of the…
Fluctuational transitions between two co-existing chaotic attractors, separated by a fractal basin boundary, are studied in a discrete dynamical system. It is shown that the mechanism for such transitions is determined by a hierarchy of…
I study two-stage hybrid inflation driven by moduli fields, corresponding to flat directions of supersymmetry, lifted by supergravity corrections. The first stage corresponds to a period of either fast-roll or `locked' inflation, induced by…
During inflationary preheating, the energy stored in the inflaton field is rapidly converted into excitations of other entropy fields. This stage is characterized by exponential particle production due to parametric resonance and is…
Inflationary models, especially those with plateau-type potentials, are consistent with the cosmological data, but inflation itself does not resolve the initial singularity. This singularity is resolved, for example, by the idea of the…
We analyze the evolution of the perturbations in the inflaton field and metric following the end of inflation. We present accurate analytic approximations for the perturbations, showing that the coherent oscillations of the…
We investigate the possibility that inflation originates from a composite field theory, in terms of an effective chiral Lagrangian involving a dilaton and pions. The walking dynamics of the theory constrain the potential in a specific way,…
We consider the dynamics of a multi-component scalar field on super-horizon scales in the context of inflationary cosmology. We present a method to solve the perturbation equations on super- horizon scales, i.e., in the long wavelength…