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Alexander Lukyanenko

Publications and source records attributed to Alexander Lukyanenko.

At least 19 recordsLinked to original sources

CPT symmetry in the mirror universe

A model of a two-sheeted universe in the quantum theory of gravity is proposed, based on the definition of 3D invariant and gauge-invariant proper time of the universe. A uniform time in a closed universe is introduced in the class of equivalent reference systems defined by the spectrum of a Hermitian 3D operator on the space of Dirac bi-spinors, the equality to zero of which is equivalent to a system of gravitational constraints. Based on the analogy with the Lorentz-invariant quantum field theory in Minkowski space and the definition of discrete C-, P- and T-transformations separately, the principle of CPT symmetry in a two-sheeted universe is formulated. A covariant quantum theory of matter gauge fields consistent with the charge conjugation operation in a two-sheeted universe is proposed. The CPT symmetric state of a homogeneous isotropic two-sheeted model of the universe is constructed by an iterative method in which the no-boundary Hartle--Hawking wave function is used as a zeroth approximation.

gr-qc

Is the EPR paradox really a paradox?

If the excitation of a system of quantized fields with a given set of quantum numbers does not exist, the amplitude of the triggering of the source is zero. A system with a source of two photons in a singlet state and two photon detectors is considered in detail. It is shown that the condition of operation of one detector with a given direction of photon polarization uniquely determines the adequate choice of direction and polarization for the second detector. This conclusion is in accordance with the laws of motion and conservation of quantum numbers of excitations in a system of quantized fields.

quant-ph

Observer in quantum cosmology

Within the framework of the new formalism of quantum theory - the quantum principle of least action - the initial state of the universe is determined, which is an analogue of the Hartle-Hawking no-boundary wave function. The quantum evolution of the universe is modified by additional conditions in a certain compact region of space-time, which is called the observation region. Additional conditions are Noether identities related to the general covariance of the theory and internal symmetries of matter fields. The consequences of the local law of conservation of the energy-momentum tensor of matter are considered in detail. Its consequence is the deterministic nature of the motion of the energy and momentum densities of matter in the observation area. The geometric parameters of the region boundary are also determined by the deterministic motion of the matter fields inside. The choice of boundary conditions for the energy-momentum flow at the boundary serves as a mechanism for decoherence of the quantum evolution of the universe. The result of decoherence is a certain correspondence between the final state of the universe and the state of the observer in the specified region. This correspondence allows us to formulate the extremum principle in quantum cosmology, in which the action functional constructed using the final state determines the world history of the universe as the observer sees it.

gr-qc

Quantum Principle of Least Action in Dynamic Theories With Higher Derivatives

A generalized canonical form of action of dynamic theories with higher derivatives is proposed, which does not require the introduction of additional dynamic variables. This form is the initial point for the construction of quantum theory, in which the state of motion of the system is described by the wave functional on its trajectories in the configuration space, and the functional itself is an eigenvector of the action operator. The Pais-Uhlenbeck oscillator is considered as the simplest model. For this case, the correspondence between the new form of quantum theory and "ordinary" quantum mechanics has been established in the local limit, when the Pais-Uhlenbeck oscillator is reduced to the "ordinary" harmonic oscillator.

quant-ph

No-boundary Wave Functional and Own Mass of the Universe

An alternative formulation of the no-boundary initial state of the universe in the Euclidean quantum theory of gravity is proposed. Unlike the no-boundary Hartle-Hawking wave function, in which time appears together with macroscopic space-time in the semiclassical approximation, in the proposed formalism time is present from the very beginning on an equal footing with spatial coordinates. The main element of the formalism is the wave functional, which is defined on the world histories of the universe. This ensures formal 4D covariance of the theory. The wave functional is defined independently of the wave function as an eigenvector of the action operator. The shape of the Origin region, together with the boundary conditions, is determined by the structure of the total energy, which includes the 3D invariant contribution of the expansion energy of the universe with a minus sign. The proper mass of the universe arises as a non-zero value of the expansion energy in the Origin and, over time, splits into a spectrum of proper masses of 3D invariant dynamic modes. 4D covariance is restored at zero own mass of the universe.

gr-qc

Does the Universe have its own mass?

Within the framework of the previously proposed formulation of the quantum theory of gravity in terms of world histories, it was suggested that the universe has its own mass. This quantity is analogous to the mass of a particle in relativistic mechanics. The mass of the universe is a distribution of non-zero values of gravitational constraints, which arises and changes in time as a consequence of the initial conditions for fundamental dynamic variables. A formulation of the Euclidean quantum theory of gravity is also proposed to determine the initial state, which can be the source of the universe's own mass. Being unrelated to ordinary matter, the distribution of its own mass affects the geometry of space and forms a dedicated frame of reference. The existence of selected reference systems is taken into account by the corresponding modification of the system of quantum gravitational links. A variant of such a modification of the Wheeler-De Witt equation is the operator representation of gravitational constraints, which, together with the state of the universe, determines the parameters of the reference system in the form of a distribution of the spinor field on a spatial section.

gr-qc

On Statistical Distribution for Adiabatically Isolated Body

The statistical distribution for the case of an adiabatically isolated body was obtained in the framework of covariant quantum theory and Wick's rotation in the complex time plane. The covariant formulation of the mechanics of an isolated system lies in the rejection of absolute time and the introduction of proper time as an independent dynamic variable. The equation of motion of proper time is the law of conservation of energy. In this case, the energy of an isolated system is an external parameter for the modified distribution instead of temperature.

cond-mat.stat-mech

On the Birth of the Universe and Time

A theory of the initial state of the universe is proposed within the framework of the Euclidean quantum theory of gravity. The theory is based on a quantum representation in which the action functional is implemented as an operator on the space of wave functionals depending on the 4D space metric and matter fields. The initial construction object is the eigenvalue of the action operator in the area of the Origin of the universe with the given values of the 3D metric and matter fields on the boundary. The wave function of the initial state is plotted as an exponential of this eigenvalue, after a Wick rotation in the complex plane of the radial variable of the Euclidean 4D space. An estimate of the initial radius of the universe is proposed.

gr-qc

Wave Functional of the Universe and Time

A version of the quantum theory of gravity based on the concept of the wave functional of the universe is proposed. To determine the physical wave functional, the quantum principle of least action is formulated as a secular equation for the corresponding action operator. Its solution, the wave functional, is an invariant of general covariant transformations of space-time. In the new formulation, the history of the evolution of the universe is described in terms of coordinate time together with arbitrary lapse and shift functions, which makes this description close to the formulation of the principle of general covariance in the classical theory of Einstein's gravity. In the new formulation of the quantum theory, an invariant parameter of the evolutionary time of the universe is defined, which is a generalization of the classical geodesic time, measured by a standard clock along time-like geodesics.

gr-qc

Local charge conservation law as a source of gauge condition in quantum electrodynamics

A formulation of quantum electrodynamics is proposed, in which the local law of conservation of electric charge serves as the source of the gauge condition. The equations of motion of the gauge variable and the density of the charge distribution in space following from this law are introduced into the quantum theory as additional conditions. Along with fixing the gauge, the interaction of charges in the modified quantum theory is described by the dynamics of the charge distribution density. The asymptotic states of free particles at spatial infinity are replaced by the initial and final states of the electromagnetic system in the form of charged wave packets.

hep-th

Feynman Functional Integral in the Fokker Theory

The equivalence of two formulations of Fokker's quantum theory is proved - based on the Feynman functional integral representation of the propagator for a system of charges with direct electromagnetic interaction and the quantum principle of least action as an analogue of the Schrödinger wave equation. The common basis for the two approaches is the generalized canonical form of Fokker's action.

quant-ph

A Natural Gauge in Quantum Electrodynamics

An alternative representation of the kernel of the evolution operator in quantum electrodynamics is obtained in the form of a functional integral, in which the gauge momentum corresponding to the Gaussian constraint is excluded from the dynamics. The natural gauge condition, that arises as a result of this representation, leaves the integration only over gauge invariant canonical variables.

hep-th

A Way of Separating Dynamics and Gauge Transformations in Yang-Mills Theory

A modification of the gauge theory is proposed, in which the set of generalized coordinates is supplemented with symmetry transformation parameters, and a condition is additionally imposed on the latter that ensures the classical character of their dynamics in quantum theory. As a result, additional dynamic variables and transverse physical degrees of freedom in the Hamiltonian are separated. The classical theory of the Yang-Mills field is considered.

hep-th

Proper Time and Mass of the Universe

A modification of the homogeneous isotropic model of the Friedman universe with a scalar field is proposed, in which the proper time of the universe is added to the dynamic variables under the additional condition of its classical dynamics. Along with proper time, an additional parameter is included in the modified theory, which is an analog of the rest mass of a relativistic particle. Assuming the dependence of the gravitational constant on proper time, we obtain the rest mass as an additional dynamic variable.

gr-qc

Feynman Propagator for Interacting Electrons in the Quantum Fokker Theory

A modification of the Fokker action is proposed, which allows one to formulate the covariant quantum theory of the charge system, in which the proper time of each particle serves as the evolution parameter and the particles themselves receive an additional quantum number - spin. The modification consists in adding to the Fokker action its variation generated by the infinitesimal shifts of the proper time parameters. As a result, the proper time parameters become observable at the quantum level.

quant-ph

Feynman Propagator for a System of Interacting Scalar Particles in the Fokker Theory

A generalized canonical formulation of the theory of the electromagnetic Fokker interaction for a system of two particles is proposed. The functional integral on the generalized phase space is defined as the initial one in quantum theory. After integration over the momenta, the measure of integration in the generalized configuration space of world particle lines is determined. The problem of dynamic interpretation of the Feynman propagator for a system of particles with independent proper time parameters is discussed. A modification of the propagator is proposed, in which the role of independent time parameters is taken by the time coordinates of the particles in Minkowski space.

quant-ph

Time and Observables in Covariant Quantum Theory

A modification of the covariant theory is proposed in which the self-energy of the system, corresponding to time-like degrees of freedom in the configuration space, preserves the classical law of change in quantum theory. As a result, proper time in covariant quantum theory takes on a dynamic meaning. As applications of the new formalism, a modification of the relativistic quantum mechanics of a scalar particle and a homogeneous model of the universe is considered.

gr-qc

On the Quantum Creation of Matter in the Expanding Universe

Quantum Action Principle which has been used as a ground for a probabilistic interpretation of one-particle relativistic quantum mechanics \cite{GLL} is applied to quantum cosmology. The quantum creation of matter in a minisuperspace model with one homogeneous scalar field is considered. The initial state of the universe is defined as a stationary ground state of the Hamiltonian with the Euclidean signature in which the mean value of the universe radius is equal to the Plank length and the number of the scalar field quanta is equal zero. We interpret the change of the signature as the universe "birth". From this moment of time the dynamics of the scale factor is considered as classical. The real phase of the amplitude of the creation process is taken as a quantum action. The balance between matter and gravitation energies in the creation process is fulfilled by the condition of the stationarity of the quantum action with respect to the internal time of the universe.

gr-qc