相关论文: Accelerated expansion of a universe containing a s…
The solution of dark energy problem in the models without scalars is presented. It is shown that late-time accelerating cosmology may be generated by the ideal fluid with some implicit equation of state. The universe evolution within…
In the simplest Higgs phase of gravity called ghost condensation, an accelerating universe with a phantom era (w<-1) can be realized without ghost or any other instabilities. In this paper we show how to reconstruct the potential in the…
Open quantum systems can be systematically controlled by making changes to their environment. A well-known example is the spontaneous radiative decay of an electronically excited emitter, such as an atom or a molecule, which is…
Accelerating universe or the existence of a small and positive cosmological constant is probably the most pressing obstacle as well as opportunity to significantly improving the models of four-dimensional cosmology from fundamental theories…
The effective action is derived for a self-interacting theory with a finite fixed $O(2)$ charge at finite temperature in curved spacetime. We obtain the high temperature expansion of the effective action in the weak coupling limit. In the…
A simple model of Bose-Einstein condensation of interacting particles is proposed. It is shown that in the condensate state the dependence of thermodynamic quantities on the interaction constant does not allow an expansion in powers of the…
The properties of systems with Bose-Einstein condensate in external time-independent random potentials are investigated in the frame of a self-consistent stochastic mean-field approximation. General considerations are presented, which are…
A new exactly solvable model for the evolution of relativistic kinetic system interacting with an internal stochastic reservoir under the influence of a gravitational background expansion is established. This model of self-interaction is…
We explain an accelerated expansion of the present universe, suggested from observations of supernovae of type Ia at high redshift, by introducing an anti-frictional force that is self-consistently exerted on the particles of the cosmic…
In the hydrodynamic approximation we obtain analytic solutions to the Gross-Pitaevskii equation with positive scattering length which describe expansions of the Bose-Einstein condensates in quasi-one and quasi-two dimensional geometries.…
Increasing astronomical evidence indicates that the expansion of the universe is accelerating. By simply solving Einstein equations we show in this letter that a wide class of generic quintessence models leading to eternal acceleration is…
The phenomenon of Bose-Einstein condensation is traditionally associated with and experimentally verified for low temperatures: either of nano-Kelvin scale for alkali atoms [1-3] or room temperatures for quasi-particles [4,5] or photons in…
We present a comprehensive theoretical investigation of Bose-Einstein condensates (BECs) and their manifestations in astrophysical and cosmological contexts. Building upon the foundations of quantum statistics in curved spacetime, we derive…
We study Bose-Einstein condensation and formation of Bose stars in the virialized dark matter halos/miniclusters by universal gravitational interactions. We prove that this phenomenon does occur and it is described by kinetic equation. We…
Particle production processes in the expanding universe are described within a simple kinetic model. The equilibrium conditions for a Maxwell-Boltzmann gas with variable particle number are investigated. We find that radiation and…
We show that the phase transition from the decelerating universe to the accelerating universe, which is of relevance to the cosmological coincidence problem, is possible in the semiclassically quantized two-dimensional dilaton gravity by…
We perform large-scale cosmological simulations that solve Einstein's equations directly via numerical relativity. Starting with initial conditions sampled from the cosmic microwave background, we track the emergence of a cosmic web without…
We study the occurrence of a Bose-Einstein transition in a dilute gas with repulsive interactions, starting from temperatures above the transition temperature. The formalism, based on the use of Ursell operators, allows us to evaluate the…
We propose that the existence of the string landscape suggests the universe can be in a quantum glass state, where an extremely large viscosity is generated, and long distance dynamics slows down. At the same time, the short distance…
Theoretical approaches to explaining the observed acceleration of the universe are reviewed. We briefly discuss the evidence for cosmic acceleration, and the implications for standard General Relativity coupled to conventional sources of…