Confinement in a Model with Condensate of the Scalar Field

The idea of ``soft'' confinement when the lifetime of hadron with respect to quark-gluon channel of decay is greater or at least of the order of some characteristic time for our Universe is considered. Within the framework of a model of three nonlinearly interacting fields the explicit form of an effective potential is found. It provides the confinement of a massive particle within the limited region of space by means of constant component of the potential which arises as a result of reorganization of vacuum of one of the scalar fields. It is shown that the lifetime of hadron being equal to the age of the Universe leads to the Higgs boson with the mass m > 63.7 GeV and realistic self-constant.Comment: 6 pages, 2 EPS figure

K-matter as Mach's principle realization

It is shown that if one takes into account Mach's principle in the form which follows from quantum theory and considers it as a complementary constraint between the parameters which characterize the energy density and geometry of the universe in addition to Einstein equations for a FRW universe, non-relativistic matter transforms into an analogue of K-matter. The exact solutions of the Einstein equations for the universe with such matter and cosmological constant are found. It is demonstrated that the Machian universe under consideration with a nonzero cosmological constant is equivalent to the open de Sitter universe. In the limit of zero cosmological constant such a universe evolves as a Milne universe, but in contrast to it, it contains matter with nonzero energy density. The possible application of proposed approach to the description of the present cosmological data is discussed. The problem of the age of the universe is considered as an example.Comment: 9 pages, based on the talk given at International Conference on the Astroparticle Physics, Gravitation and Cosmology (7 - 10 June, 2011, Kiev, Ukraine

Production of matter in the universe via after-GUT interaction

In this paper we propose a model of production of ordinary and dark matter in the decay of a hypothetical antigravitating medium in the form of a condensate of (zero-momentum) spinless massive particles (denoted as $\phi$) which fills the universe. The decays of $\phi$-particles into baryons, leptons, and dark matter particles are caused by some (after-GUT) interaction with the mass scale between the electroweak and grand unification. The observed dark energy is identified with a portion of a condensate which has not decayed up to the instant of measurement. The decay rate of $\phi$-particles $\Gamma_{\phi}$ is expressed through the three parameters - the coupling constant $\alpha_{X}$, the mass scale $M_{X}$ which defines the mass of $X$-particle as the mediator of after-GUT interaction, and the energy imparted to the decay products. We show that the masses of dark matter particle $m_{\chi}\approx 5$ GeV and $\phi$-particle $m_{\phi}\approx 15$ GeV can be extracted from the 7-year WMAP and other astrophysical data about the contributions of baryon, dark matter, and dark energy densities to the total matter-energy density budget in our universe. Such a mass of light WIMP dark matter agrees with the recent observations of CoGeNT, DAMA, and CDMS. The obtained masses of $\phi$- and dark matter particle are concordant with the coupling constant of after-GUT interaction $\alpha_{X} \sim 1/70 at$M_{X} \sim 6 \times 10^{10}$GeV, and the decay rate$\Gamma_{\phi} \approx 2 \times 10^{-18}\, {s}^{-1}$. The cross-sections of the reactions in which dark matter particles can be produced are calculatedComment: 15 pages, 2 EPS figures, v.2: a few sections are revised, additional explanations and some corrections are provide

Quantum dynamics of the early universe

Quantum gravity may shed light on the prehistory of the universe. Quantum corrections to gravity affect the dynamics of the expansion of the universe. Their influence is studied on the example of the exactly solvable quantum model. The corrections to the energy density and pressure lead to the emergence of an additional attraction (like dark matter) or repulsion (like dark energy) in the quantum system of the gravitating matter and radiation. The model explains the accelerating expansion (inflation) in the early universe (the domain of comparatively small values of quantum numbers) and a later transition from the decelerating expansion to the accelerating expansion of the universe (the domain of the very large values of quantum numbers) from a single approach. The generation of primordial fluctuations of the energy density at the expense of the change of sign of the quantum correction to the pressure is discussed.Comment: 5 two-column pages, 4 EPS figures; v.2: refreshed and based on a talk given at the conference Fundamentals of Astroparticle and Quantum Physics, 17 - 23 September, 2017, BITP, Kyiv, Ukrain

Properties of the quasistationary universe in context of the Big-bang cosmology problems

Old and new puzzles of cosmology are reexamined from the point of view of quantum theory of the universe developed here. It is shown that in proposed approach the difficulties of the standard cosmology do not arise. The theory predicts the observed dimensions of the nonhomogeneities of matter density and the amplitude of the fluctuations of the cosmic background radiation temperature in the Universe and points to a new quantum mechanism of their origin. It allows to obtain the value of the deceleration parameter which is in good agreement with the recent SNe Ia measurements. The theory explains the large value of entropy of the Universe and describes other parameters.Comment: 21 pages, 1 EPS figure, 1 table; revised subsection 3.

Semi-classical Universe Near Initial Singularity

The properties of the quantum universe on extremely small spacetime scales are studied in the semi-classical approach to the well-defined quantum model. It is shown that near the initial cosmological singularity point quantum gravity effects ~ h exhibit themselves in the form of additional matter source with the negative pressure and the equation of state as for ultrastiff matter. The analytical solution of the equations of theory of gravity, in which matter is represented by the radiation and additional matter source of quantum nature, is found. It is shown that in the stage of the evolution of the universe, when quantum corrections ~ h dominate over the radiation, the geometry of the universe is described by the metric which is conformal to a metric of a unit four-sphere in a five-dimensional Euclidean flat space. In the radiation dominated era the metric is found to be conformal to a unit hyperboloid embedded in a five-dimensional Lorentz-signatured flat space. The origin of the universe can be interpreted as a quantum transition of the system from the region in a phase space with a trajectory in imaginary time into the region, where the equations of motion have the solution in real time. Near the boundary between two regions the universe undergoes almost an exponential expansion which passes smoothly into the expansion under the action of radiation dominating over matter. As a result of such a quantum transition the geometry of the universe changes. This agrees with the hypothesis about the possible change of geometry after the nucleation of expanding universe from `nothing'.Comment: 14 pages, 1 EPS figur

Comparative description of the evolving universe in classical and quantum geometrodynamics

The description of the universe evolving in time according to general relativity is given in comparison with the quantum description of the same universe in terms of semiclassical wave functions. The spacetime geometry is determined by the Robertson-Walker metric. It is shown that the main equation of the quantum geometrodynamics is reduced to the non-linear Hamilton-Jacobi equation. Its non-linearity is caused by a new source of the gravitational field, which has a purely quantum dynamical nature, and is additional to ordinary matter sources. In the semiclassical approximation, the non-linear equation of motion is linearized and reduces to the Friedmann equation with the additional quantum source of gravity (or anti-gravity) in the form of the stiff Zel'dovich matter. The semiclassical wave functions of the universe, in which different types of matter-energies dominate, are obtained. As examples, the cases of the domination of radiation, barotropic fluid, or new quantum matter-energy are discussed. The probability of the transition from the quantum state, where radiation dominates into the state, in which barotropic fluid in the form of dust is dominant, is calculated. This probability has the same order of magnitude as the matter density contrast in the era of matter-radiation equality.Comment: 17 pages, v.2: Sect. 2 and 6 are revised, v.3: Sect. 2 is supplemented, new references are adde

Dark matter and dark energy production in quantum model of the universe

The quantum model of the homogeneous, isotropic, and spatially closed universe predicts an existence of two types of collective quantum states in the universe. The states of one type characterize a gravitational field, the others describe a matter (uniform scalar) field. In the first stage of the evolution of the universe a primordial scalar field evolves slowly into its vacuum-like state. In the second stage the scalar field oscillates about an equilibrium due to the quantum fluctuations. The universe is being filled with matter in the form of elementary quantum excitations of the vibrations of the scalar field. The separate quantum excitations are characterized by non-zero values of their energies (masses). Under the action of gravitational forces mainly these excitations decay into ordinary particles (baryons and leptons) and dark matter. The elementary quantum excitations of the vibrations of the scalar field which have not decayed up to now form dark energy. The numerical estimations lead to realistic values of both the matter density \Omega_{M} = 0.29 (with the contributions from dark matter, \Omega_{DM} = 0.25, and optically bright baryons, \Omega_{stars} = 0.0025) and the dark energy density \Omega_{X} = 0.71 if one takes that the mean energy ~ 10 GeV is released in decay of dark energy quantum and fixes baryonic component \Omega_{B} = 0.04 according to observational data. The energy (mass) of dark energy quantum is equal to ~ 17 GeV and the energy > 2 x 10^{10} GeV is needed in order to detect it. Dark matter particle has the mass ~ 6 GeV. The Jeans mass for dark matter which is considered as a gas of such massive particles is equal to M_{J} ~ 10^{5} M_{\odot}.Comment: 21 pages, 2 EPS figure; full version is submitted to the volume "Progress in Dark Matter Research" (Nova Science

On the nature of mass-energy constituents of the universe

On the basis of our quantum cosmological approach we show that there can be two previously unknown types of collective states in the universe. One of them relates to a gravitational field, another is connected with a matter (scalar) field which fills the universe on all stages of its evolution. The increase in number of the quanta of the collective excitations of the gravitational field manifests itself as an expansion of the universe. The collective excitations of the scalar field above its true vacuum reveal themselves mainly in the form of dark matter and energy. Under the action of the gravitational forces they decay and produce the non-baryonic dark matter, optically bright and dark baryons. We have calculated the corresponding energy densities which prove to be in good agreement with the data from the recent observations.Comment: 15 page

Universe on Extremely Small Spacetime Scales: Quantum Geometrodynamical Approach

The semi-classical approach to the quantum geometrodynamical model is used for the description of the properties of the universe on extremely small spacetime scales. Quantum theory for a homogeneous, isotropic and closed universe is constructed on the basis of a Hamiltonian formalism with the use of material reference system as a dynamical system defined by macroscopic relativistic matter. The equations of the model are reduced to the form of the Einstein-type equations in which the matter energy density has two components of quantum nature, which behave as antigravitating fluids. The first component does not vanish in the limit h -> 0 and can be associated with dark energy. The second component is described by extremely rigid equation of state and goes to zero after the transition to large spacetime scales. On small spacetime scales this quantum correction determines the geometry of the universe. This geometry is conformal to a unit four-sphere embedded in a five-dimensional Euclidean flat space. When reaching the post-Planck era, the geometry of the universe changes into the geometry conformal to a unit four-hyperboloid in a five-dimensional Lorentz-signatured flat space. Near the boundary between two regions the universe undergoes almost an exponential expansion which passes smoothly into the expansion under the action of radiation dominating over matter which is described by the standard cosmological model.Comment: 18 pages, 4 EPS figur