相关论文: Understanding gravitational particle production in…

In inflationary cosmology, the particles constituting the Universe are created after inflation in the process of reheating due to the interaction with the oscillating inflaton field. We briefly review the basics of the slow reheating, and…

The success of primordial nucleosynthesis imposes stringent bounds on the abundance of gravitational relics. This is particularly true for gravitinos, which - for models with gravitationally mediated supersymmetry breaking - are expected to…

We propose a mechanism of preheating stage after inflation, using a new idea of parametrically amplified super-radiance. Highly coherent state, characterized by macro-coherence of scalar field coupled to produced massless particle in pairs,…

We estimate dark matter density for the Universe with a reheating temperature smaller than the mass of dark matter, assuming dark matter to be a weakly interacting massive particle. During the reheating process, an inflaton decays and…

We consider the abundance of gravitinos created from the vacuum fluctuation, in a class of `new' inflation models for which global supersymmetry is a good approximation. Immediately after inflation, gravitinos are produced, with number…

At high temperatures, gravitinos are generated in inelastic scattering processes with particles that are in thermal equilibrium with the hot primordial plasma. We consider the regeneration of gravitinos that starts with completion of…

At the end of inflation the universe is frozen in a near zero-entropy state with energy density in a coherent scalar field and must be ``defrosted'' to produce the observed entropy and baryon number. We propose that the baryon asymmetry is…

We consider the decay of a massive particle under the complete or partial domination of the kinetic energy density generated by a quintessential exponential model and we impose a number of observational constraints originating from…

Quintessential inflation models provide a framework that simultaneously describes inflation and dynamical dark energy, the latter of which has recently received growing support from DESI observations. A distinctive feature of these models…

The non-thermal production of dark matter (DM) usually requires very tiny couplings of the dark sector with the visible sector and therefore is notoriously challenging to hunt in laboratory experiments. Here we propose a novel pathway to…

For the first time, the possibility of generation of thermal gravitational waves from warm inflation is investigated with cosmic microwave background. Gravitons produced from the quantum fluctuations during warm inflation are found to carry…

We study the possibility that particle production during inflation could source observable gravity waves on scales relevant for Cosmic Microwave Background experiments. A crucial constraint on such scenarios arises because particle…

Reheating after inflation occurs due to particle production by the oscillating inflaton field. In this paper we describe the perturbative approach to reheating, and then concentrate on effects beyond the perturbation theory. They are…

Quintessential inflation--in which a single scalar field plays the role of the inflaton and quintessence--from a sum of exponentials potential V = A (exp{5 phi}+exp{sqrt{2} phi}) or V = A (exp{5 phi}+exp{phi}) or a cosh potential V = 2A…

We consider a model of inflation which has recently been proposed in the literature and where inflation is induced by corrections to the energy density coming from the non-commutativity of spacetime. We show that the very rapid inflationary…

We investigate the possibility of achieving post-inflationary reheating exclusively through the gravitational interaction in Starobinsky inflation, which itself assumes nothing but gravity. We consider the possibility that the reheating…

Heavy long-lived particles are abundant in BSM physics and will, under generic circumstances, get to dominate the energy density of the universe. The resulting matter dominated era has to end before the onset of Big Bang Nucleosynthesis…

In low scale quantum gravity scenarios the fundamental scale of nature can be as low as TeV, in order to address the naturalness of the electroweak scale. A number of difficulties arise in constructing specific models; stabilisation of the…

Particle phase transitions in the early universe including electroweak and grand unification ones are well-studied subjects. We point out that there are new possible particle phase transitions around inflation. Those new inflationary…

Quintessential inflation is studied using a string modulus as the inflaton - quintessence field. It is assumed that the modulus crosses an enhanced symmetry point (ESP) in field space. Particle production at the ESP temporarily traps the…