31 research outputs found
The Lagrangian and Hamiltonian Aspects of the Electrodynamic Vacuum-Field Theory Models
We review the modern classical electrodynamics problems and present the
related main fundamental principles characterizing the electrodynamical
vacuum-field structure. We analyze the models of the vacuum field medium and
charged point particle dynamics using the developed field theory concepts.
There is also described a new approach to the classical Maxwell theory based on
the derived and newly interpreted basic equations making use of the vacuum
field theory approach. In particular, there are obtained the main classical
special relativity theory relations and their new explanations. The well known
Feynman approach to Maxwell electromagnetic equations and the Lorentz type
force derivation is also discussed in detail. A related charged point particle
dynamics and a hadronic string model analysis is also presented. We also
revisited and reanalyzed the classical Lorentz force expression in arbitrary
non-inertial reference frames and present some new interpretations of the
relations between special relativity theory and its quantum mechanical aspects.
Some results related with the charge particle radiation problem and the
magnetic potential topological aspects are discussed. The electromagnetic
Dirac-Fock-Podolsky problem of the Maxwell and Yang-Mills type dynamical
systems is analyzed within the classical Dirac-Marsden-Weinstein symplectic
reduction theory. The problem of constructing Fock type representations and
retrieving their creation-annihilation operator structure is analyzed. An
application of the suitable current algebra representation to describing the
non-relativistic Aharonov-Bohm paradox is presented. The current algebra
coherent functional representations are constructed and their importance
subject to the linearization problem of nonlinear dynamical systems in Hilbert
spaces is demonstrated.Comment: 70 p, revie
Reparametrization-Invariant Path Integral in GR and "Big Bang" of Quantum Universe
The reparametrization-invariant generating functional for the unitary and
causal perturbation theory in general relativity in a finite space-time is
obtained. The region of validity of the Faddeev-Popov-DeWitt functional is
studied. It is shown that the invariant content of general relativity as a
constrained system can be covered by two "equivalent" unconstrained systems:
the "dynamic" (with "dynamic" evolution parameter as the metric scale factor)
and "geometric" (given by the Levi-Civita type canonical transformation to the
action-angle variables where the energy constraint converts into a new
momentum). "Big Bang", the Hubble evolution, and creation of matter fields by
the "geometric" vacuum are described by the inverted Levi-Civita (LC)
transformation of the geomeric system into the dynamic one. The particular case
of the LC transformations are the Bogoliubov ones of the particle variables
(diagonalizing the dynamic Hamiltonian) to the quasiparticles (diagonalizing
the equations of motion). The choice of initial conditions for the "Big Bang"
in the form of the Bogoliubov (squeezed) vacuum reproduces all stages of the
evolution of the Friedmann-Robertson-Walker Universe in their conformal
(Hoyle-Narlikar) versions.Comment: 21 pages, latex, 4 figures in postscrip
Collective coherent population trapping in a thermal field
We analyzed the efficiency of coherent population trapping (CPT) in a
superposition of the ground states of three-level atoms under the influence of
the decoherence process induced by a broadband thermal field. We showed that in
a single atom there is no perfect CPT when the atomic transitions are affected
by the thermal field. The perfect CPT may occur when only one of the two atomic
transitions is affected by the thermal field. In the case when both atomic
transitions are affected by the thermal field, we demonstrated that regardless
of the intensity of the thermal field the destructive effect on the CPT can be
circumvented by the collective behavior of the atoms. An analytic expression
was obtained for the populations of the upper atomic levels which can be
considered as a measure of the level of thermal decoherence. The results show
that the collective interaction between the atoms can significantly enhance the
population trapping in that the population of the upper state decreases with
increased number of atoms. The physical origin of this feature was explained by
the semiclassical dressed atom model of the system. We introduced the concept
of multiatom collective coherent population trapping by demonstrating the
existence of collective (entangled) states whose storage capacity is larger
than that of the equivalent states of independent atoms.Comment: Accepted for publication in Phys. Rev.
Effects of interatomic interaction on cooperative relaxation of two-level atoms
We study effects of direct interatomic interaction on cooperative processes
in atom-photon dynamics. Using a model of two-level atoms with Ising-type
interaction as an example, it is demonstrated that interparticle interaction
combined with atom-field coupling can introduce additional interatomic
correlations acting as a phase synchronizing factor. For the case of weakly
interacting atoms with , where is the interparticle
coupling constant and is the atomic frequency, dynamical regimes of
cooperative relaxation of atoms are analyzed in Born-Markov approximation both
numerically and using the mean field approximation. We show that interparticle
correlations induced by the direct interaction result in inhibition of
incoherent spontaneous decay leading to the regime of collective pulse
relaxation which differs from superradiance in nature. For superradiant
transition, the synchronizing effect of interatomic interaction is found to
manifest itself in enhancement of superradiance. When the interaction is strong
and , one-partice one-photon transitions are excluded and
transition to the regime of multiphoton relaxation occurs. Using a simple model
of two atoms in a high-Q single mode cavity we show that such transition is
accompanied by Rabi oscillations involving many-atom multiphoton states.
Dephasing effect of dipole-dipole interaction and solitonic mechanism of
relaxation are discussed.Comment: 34 pages, 8 figure
The Relativistic Electrodynamics Least Action Principles Revisited: New Charged Point Particle and Hadronic String Models Analysis
The classical relativistic least action principle is revisited from the
vacuum field theory approach. New physically motivated versions of relativistic
Lorentz type forces are derived, a new relativistic hadronic string model is
proposed and analyzed in detail.Comment: n/
On Locality in Quantum General Relativity and Quantum Gravity
The physical concept of locality is first analyzed in the special
relativistic quantum regime, and compared with that of microcausality and the
local commutativity of quantum fields. Its extrapolation to quantum general
relativity on quantum bundles over curved spacetime is then described. It is
shown that the resulting formulation of quantum-geometric locality based on the
concept of local quantum frame incorporating a fundamental length embodies the
key geometric and topological aspects of this concept. Taken in conjunction
with the strong equivalence principle and the path-integral formulation of
quantum propagation, quantum-geometric locality leads in a natural manner to
the formulation of quantum-geometric propagation in curved spacetime. Its
extrapolation to geometric quantum gravity formulated over quantum spacetime is
described and analyzed.Comment: Mac-Word file translated to postscript for submission. The author may
be reached at: [email protected] To appear in Found. Phys. vol. 27,
199
Non Degenerate Dual Atomic Parametric Amplifier: Entangled Atomic Fields
In this paper, we investigate the dynamics of two coupled quantum degenerate
atomic fields (BEC) interacting with two classical optical fields in the
nonlinear atom optics regime. Two photon interaction produces entangled
atom-atom pairs which exhibit nonclassical correlations. Since the system
involves the creation of two correlated atom pairs, we call it the
nondegenerate dual atomic parametric amplifier.Comment: 5 figure