Related papers: Ultralight particle creation during fresh inflatio…
In the past decade, the importance of dissipation and fluctuation to inflationary dynamics has been realized and has led to a new picture of inflation called warm inflation. Although these phenomena are common to condensed matter systems,…
We propose a qualitatively new mechanism for generating cosmological fluctuations from inflation. The non-equilibrium excitation of interacting scalar fields often evolves into infra-red (IR) and ultra-violet (UV) cascading, resulting in an…
We study the possibility that particle production during inflation can source the required power spectrum for dark matter (DM) primordial black holes (PBH) formation. We consider the scalar and the gauge quanta production in inflation…
A new theory of thermal history after inflation is outlined by taking into account the effect of parametric resonance caused by inflaton oscillation. A typical outcome is existence of a high temperature phase, that makes possible GUT…
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.…
The longitudinal mode of a massive vector field, generated during inflation, offers a well-motivated and phenomenologically rich candidate for dark matter. We show that a rapid variation in the mass of the vector boson, occurring during a…
We study the initial value problem of new inflation models in the scheme of supergravity. We find that an inflaton generally acquires a mass of the order of the Hubble parameter via gravitationally suppressed interactions with particles in…
The density fluctuations that we observe in the universe today are thought to originate from quantum fluctuations produced during a phase of the early universe called inflation. By evolving a wavefunction describing two coupled Fourier…
Inflation provides a natural mechanism to account for the origin of cosmic structures. The generation of primordial inhomogeneities during inflation can be understood via the spontaneous creation of quanta from the vacuum. We show that when…
We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local B-L, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To…
We investigate the particle production due to parametric resonances in model of inflation where the lightest composite state stemming from the minimal walking technicolor theory plays the role of the inflaton. For model of inflation, the…
We point out that inflaton decay products acquire plasma masses during the reheating phase following inflation. The plasma masses may render inflaton decay kinematicaly forbidden, causing the temperature to remain frozen for a period at a…
We summarize three recent efforts to constrain the first few moments of cosmic creation before and during the epoch of inflation. We consider two means to explain a slight dip in the power spectrum of the cosmic microwave background for…
In the first stages of inflationary reheating, the temperature of the radiation produced by inflaton decays is typically higher than the commonly defined reheating temperature $T_{RH} \sim (\Gamma_\phi M_P)^{1/2}$ where $\Gamma_\phi$ is the…
The theory of reheating of the Universe after inflation is developed. The transition from inflation to the hot Universe turns out to be strongly model-dependent and typically consists of several stages. Immediately after inflation the field…
Macroscopic plasma polarization, which is created by gravitation and other mass-acting (inertial) forces in massive astrophysical objects is under discussion. Non-ideality effect due to strong Coulomb interaction of charged particles is…
We study some of the roles for unparticles in an inflationary universe. Unparticles by themselves are not appropriate for generating the primordial perturbations since their power spectrum does not match what has been inferred from…
We study the problem of scalar particle production after inflation by a rapidly oscillating inflaton field. We use the framework of the chaotic inflation scenario with quartic and quadratic inflaton potentials. Particular attention is paid…
We study a class of FRW spacetimes with a nonminimally coupled light massive scalar field. Values of the coupling parameter xi<0 enhance long range power in the vacuum expectation value of the energy-momentum tensor and fundamentally alter…
A theory of gravitational production of light scalar particles during and after inflation is investigated. We show that in the most interesting cases where long-wavelength fluctuations of light scalar fields can be generated during…