arXiv subjects

V. E. Kuzmichev

Publications and source records attributed to V. E. Kuzmichev.

34 records · Page 2Linked to original sources

arXiv2010

Dark energy and light WIMP dark matter from the cosmological viewpoint

We give an estimation of the masses of light dark matter particle and dark energy quasiparticle which can be extracted from the astrophysical data about the contributions of baryon, dark matter, and dark energy densities to the total matter-energy density budget in our universe. We use the quantum cosmological model in which dark energy is a condensate of quantum oscillations of primordial scalar field. The dark energy quasiparticle with the mass ~ 15 GeV is consistent with the 7-year WMAP and other data. The quasiparticles can decay with violation of CP-invariance into baryons, leptons, and dark matter. The WIMP mass ~ 5 GeV corresponds to observed values of baryon and dark matter energy densities. Such a mass agrees with the observations of CoGeNT, DAMA, and CDMS. Quasiparticles of dark energy can be registered as a constant background of radiation with the frequency ~ 3.64 x 10^{24} 1/s. Dark matter particles must exhibit themselves in the form of signals with the frequency ~ 1.21 x 10^{24} 1/s of radiation from galaxy clusters where the intensive gravitational fields produced by dark matter exist.

astro-ph.CO↗

arXiv2009

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.

gr-qc↗

arXiv2009

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'.

gr-qc↗

arXiv2008

The Big Bang quantum cosmology: The matter-energy production epoch

The exactly solvable quantum model of the homogeneous, isotropic and closed universe in the matter-energy production epoch is considered. It is assumed that the universe is originally filled with a uniform scalar field and a perfect fluid which defines a reference frame. The stationary state spectrum and the wave functions of the quantum universe are calculated. In this model the matter-energy in the universe has a component in the form of a condensate of massive zero-momentum excitation quanta of oscillations of primordial scalar field. The mean value of the scale factor of the universe in a given state is connected with the mass of a condensate by a linear relation. The nucleation rate of the universe from the initial cosmological singularity point is calculated. It is demonstrated that the process of nucleation of the universe can have an exponential (explosive) nature. The evolution of the universe is described as transitions with non-zero probabilities between the states of the universe with different masses of a condensate.

gr-qc↗

arXiv2008

Accelerating Quantum Universe

The origin of negative pressure fluid (the dark energy) is investigated in the quantum model of the homogeneous, isotropic and closed universe filled with a uniform scalar field and a perfect fluid which defines a reference frame. The equations of the model are reduced to the form which allows a direct comparison between them and the equations of the Einsteinian classical theory of gravity. It is shown that quantized scalar field has a form of a condensate which behaves as an antigravitating medium. The theory predicts an accelerating expansion of the universe even if the vacuum energy density vanishes. An antigravitating effect of a condensate has a purely quantum nature. It is shown that the universe with the parameters close to the Planck ones can go through the period of exponential expansion. The conditions under which in semi-classical approximation the universe looks effectively like spatially flat with negative deceleration parameter are determined. The reduction to the standard model of classical cosmology is discussed.

gr-qc↗

arXiv2007

An impact of the metrics probabilistic distributions on the spatial geometry of the universe in quantum model

It is shown that the homogeneous and isotropic Universe is spatially flat in the limit which takes into account the moments of infinitely large orders of probabilistic distribution of a scale factor with respect to its mean value in the state with large quantum numbers. The quantum mechanism of fine tuning of the total energy density in the Universe to the critical value at the early stage of its evolution is proposed and the reason of possible small difference between these densities during the subsequent expansion is indicated. A comparison of the predictions of the quantum model with the real Universe is given.

astro-ph↗

arXiv2005

On possible manifestation of feedback coupling between geometry and matter in a phenomenon of an accelerating expansion of the Universe

It is shown that an accelerating expansion of the present-day Universe extracted from observed luminosity of the type Ia supernovae can be explained by quantum theory which takes into account feedback coupling between geometry and matter (like in Mach's principle). At the same time an accelerating expansion of the Universe is explained by the influence of small negative cosmological constant. A comparison with the model with positive cosmological constant (dark energy) which also has obtained its theoretical grounds in a structure of the developed formalism is made. Parameters of the Universe in the states with large quantum numbers are calculated.

astro-ph↗

arXiv2004

The law of evolution of energy density in the universe imposed by quantum cosmology and its consequences

The quantum model of homogeneous and isotropic universe filled with the uniform scalar field is considered. This model predicts effective inverse square-law dependence of the mean total energy density <ρ> on the expectation value of cosmological scale factor where the averaging is performed over the state with large quantum numbers. Such a law of decreasing of <ρ> during the expansion of the universe allows to describe the observed coordinate distances to type Ia supernovae and radio galaxies in the redshift interval z = 0.01 - 1.8. A comparison with phenomenological models with the cosmological constant (ΛCDM) and with zero dark energy component (Ω_{M} = 1) is made. It is shown that observed small deviations of the coordinate distances to some sources from the predictions of above mentioned simple quantum model can be explained by the fluctuations δa of the scale factor about the average value . These fluctuations can arise due to finite widths of quasistationary states in the early universe. During expansion the fluctuations δa grow with time and manifest themselves in the form of observed relative increase or decrease of coordinate distances. The amplitudes of fluctuations δa/ calculated from observed positions of individual supernovae are in good agreement with their estimations in quantum theory. Possible consequences from the conclusions of quantum theory are discussed.

astro-ph↗

arXiv2004

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 Ω_{M} = 0.29 (with the contributions from dark matter, Ω_{DM} = 0.25, and optically bright baryons, Ω_{stars} = 0.0025) and the dark energy density Ω_{X} = 0.71 if one takes that the mean energy ~ 10 GeV is released in decay of dark energy quantum and fixes baryonic component Ω_{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}.

astro-ph↗

arXiv2004

On coordinate distances to type Ia supernovae and radio galaxies

The quantum model of the homogeneous and isotropic universe predicts logarithmic-law dependence of coordinate distance to source on redshift z which is in good agreement with type Ia supernovae and radio galaxies observations for the redshift range z = 0.01 - 1.8. A comparison with phenomenological models with dark energy in the form of cosmological constant and without dark energy component is made. Fluctuations of the cosmological scale factor about its average value which can arise in the early universe produce accelerating or decelerating expansions of space subdomains containing separate sources with high redshift whereas the universe as a whole expands at a steady rate.

astro-ph↗

arXiv2003

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.

astro-ph↗

arXiv2003

Collective excitations of quantum universe and the problem of dark matter and energy

In the present report we make an attempt to give an answer to the question of modern cosmology about the nature of the dark matter and energy in our universe. On the basis of our quantum cosmological approach, proposed in 1997-2002, we show that there can be two 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 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.

astro-ph↗

arXiv2001

Properties of the quantum universe in quasistationary states and cosmological puzzles

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 nonhomogeneities of matter density and the amplitude of fluctuations of the cosmic background radiation temperature in the Universe and points to a new quantum mechanism of their origin. The large scale structure in the Universe is explained by the growth of nonhomogeneities which arise from primordial quantum fluctuations due to finite width of quasistationary states. The theory allows to obtain the value of the deceleration parameter which is in good agreement with the recent SNe Ia measurements. It explains the large value of entropy of the Universe and describes other parameters.

astro-ph↗

arXiv2001

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.

gr-qc↗

arXiv2000

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.

hep-th↗

arXiv2000

Three Field Dynamics in (1+1)-dimensions

In a model of nonlinear system of three scalar fields the problem on dynamics of a massive particle moving in effective potential provided by two relativistic fields is solving. The potentials for these fields are chosen in the form of anti-Higgs and Higgs potentials. It is shown that the effective potential has the shape of two-hump barrier localized in spacetime. It tends to constant attractive potential at spacetime infinity. The magnitude of this constant constituent is determined by the Higgs condensate. It is shown that nonlinear equation of motion of a particle has the solutions which describe the capture of a particle by the barrier and the scattering on the barrier.

hep-th↗