46 research outputs found
О ПРОБЛЕМЕ КВАНТОВАНИЯ В ТЕОРИИ ГРАВИТАЦИИ
A perturbativ equantization proves to be possible in the framework of the field-theoretic paradigm only for weak gravitational fields. The geometric approach admits a nonperturbative quantization of both geometry as a whole and space-time. Quantum mechanics and quantum field theory may be considered in a given space-time.В рамках теоретико-полевой парадигмы пертурбативное квантование оказывается возможным только для слабых гравитационных полей. Геометрический подход допускает непертурбативное квантование как геометрии в целом, так и пространства-времени. Квантовая механика и квантовая теория поля могут рассматриваться в заданном искривлённом пространстве-времен
МАТЕМАТИЧЕСКИЕ МОДЕЛИ В ТЕОРЕТИЧЕСКОЙ ФИЗИКЕ
Quantum theory and relativity theory as well as possible reconciliation have been analyzed from the viewpoint of mathematical models being used in them, experimental affirmation, interpretations and their association with dualistic paradigms.Проанализированы квантовая теория и теория относительности, а также их возможные согласования, с точки зрения используемых в них математических моделей, экс-периментального подтверждения, интерпретаций и отнесения их к дуалистическим парадиг-мам
Об интерпретациях общей теории относительности
The article considers the assumptions of A. Eddington on the possibility to interpret gravitation outside the framework of a geometric paradigm. The results obtained are consistent with astronomic observations.Обсуждаются предположения А. Эддингтона o возможности интерпретации гравитации вне рамок геометрической парадигмы. Полученные результаты согласуются с астрономическими наблюдениями
Band-gap solitons in nonlinear optically-induced lattices
We introduce novel optical solitons that consist of a periodic and a
spatially localized components coupled nonlinearly via cross-phase modulation.
The spatially localized optical field can be treated as a gap soliton supported
by the optically-induced nonlinear grating. We find different types of these
band-gap composite solitons and demonstrate their dynamical stability.Comment: 4 pages, 5 figure
Quantum Cosmology and Open Universes
Quantum creation of Universes with compact spacelike sections that have
curvature either closed, flat or open, i.e. are studied. In the
flat and open cases, the superpotential of the Wheeler De Witt equation is
significantly modified, and as a result the qualitative behaviour of a typical
wavefunction differs from the traditional closed case. Using regularity
arguments, it is shown that the only consistent state for the wavefunction is
the Tunneling one. By computing the quantum probabilities for the curvature of
the sections, it is shown that quantum cosmology actually favours that the
Universe be open, . In all cases sufficient inflation
e-foldings is predicted: this is an improvement over classical measures that
generally are ambiguous as to whether inflation is certain to occur.Comment: 11 pages, Revtex, 7 figures. Accepted for publication in PRD. New
material and important corrections added in response to referee's repor
Quantum creation and inflationary universes: a critical appraisal
We contrast the possibility of inflation starting a) from the universe's
inception or b) from an earlier non-inflationary state. Neither case is ideal
since a) assumes quantum mechanical reasoning is straightforwardly applicable
to the early universe; while case b) requires that a singularity still be
present. Further, in agreement with Vachaspati and Trodden [1] case b) can only
solve the horizon problem if the non-inflationary phase has equation of state
.Comment: 21 pages Late
Stable multicolor periodic-wave arrays
We study the existence and stability of cnoidal periodic wave arrays
propagating in uniform quadratic nonlinear media and discover that they become
completely stable above a threshold light intensity. To the best of our
knowledge, this is the first example in physics of completely stable periodic
wave patterns propagating in conservative uniform media supporting bright
solitons.Comment: 12 pages, 3 figure
Dynamics of the Universe with global rotation
We analyze dynamics of the FRW models with global rotation in terms of
dynamical system methods. We reduce dynamics of these models to the FRW models
with some fictitious fluid which scales like radiation matter. This fluid
mimics dynamically effects of global rotation. The significance of the global
rotation of the Universe for the resolution of the acceleration and horizon
problems in cosmology is investigated. It is found that dynamics of the
Universe can be reduced to the two-dimensional Hamiltonian dynamical system.
Then the construction of the Hamiltonian allows for full classification of
evolution paths. On the phase portraits we find the domains of cosmic
acceleration for the globally rotating universe as well as the trajectories for
which the horizon problem is solved. We show that the FRW models with global
rotation are structurally stable. This proves that the universe acceleration is
due to the global rotation. It is also shown how global rotation gives a
natural explanation of the empirical relation between angular momentum for
clusters and superclusters of galaxies. The relation is obtained
as a consequence of self similarity invariance of the dynamics of the FRW model
with global rotation. In derivation of this relation we use the Lie group of
symmetry analysis of differential equation.Comment: Revtex4, 22 pages, 5 figure