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Title:
On
SU(2) Wess-Zumino-Witten Models and Stochastic
Evolutions
Author:
Jörgen Rasmussen
Comments:
9 pages, no figures
Abstract:
It is discussed how stochastic evolutions
may be connected to SU(2) Wess-Zumino-Witten
models. Transformations of primary fields
are generated by the Virasoro group and an
affine extension of the Lie group SU(2). The
transformations may be treated and linked
separately to stochastic evolutions. A combination
allows one to associate a set of stochastic
evolutions to the affine Sugawara construction.
The singular-vector decoupling generating
the Knizhnik-Zamolodchikov equations may thus
be related to stochastic evolutions. The latter
are based on an infinite-dimensional Brownian
motion
Title:
Stability of Some Solitonic Systems with
Real Scalar Fields
Authors:
J. Sadeghi and A.
Mohammadi
Comments:
8 pages, no figures
Abstract:
In this article we consider the stability
of the solitons in certain systems of scalar
fields in 1+1 dimensions. We obtain the
soliton solution by solving sets of first
order differential equations. We also study
the stability of these solutions with the
help of Jacobi Polynomials
Keywords: Solitons, Linear Stability, Jacobi
Polynomial
Title:
Spectre
des Molécules Diatomiques dans l'Approximation
de Born-Oppenheimer
Authors:
B. Messirdi and A. Senoussaoui
Comments:
13 pages, no figures
Abstract:
On étudie le spectre de $P=-h^{2}\Delta
_{x}-\Delta _{y}+V(x,y;\mu) ${\small \ sur}
{\small \ }$L^{2}\left( {\mathbb{R}}_{x}^{3}\times
{\mathbb{R}}_{y}^{3p}\right) $ {\small \ lorsque
}$h${\small \ tend vers z\'{e}ro}$,${\small
\}$p\in \mathbb{N}^{\ast }${\small \ et }$\mu
\in {{\mathbb{R}}},${\small \ dans le cas
où le potentiel }$V\left( x,y;\mu \right)
${\small \ est singulier de type de Coulomb
et radial (correspondant à }$\mu =0${\small
\ ) et où la première valeur
propre de }$Q\left( x;\mu \right) =${\small
\ }-\Delta _{y}+V\left( x,y;\mu \right) ${\small
\ sur }$L^{2}\left( {{\mathbb{R}}}_{y}^{3p}\right)
${\small \ présente une zone classiquement
accessible non born\'{e}e. En régularisant
}$P${\small \ par des changements de variables
adaptés et en utilisant une version
formelle du calcul $h$-pseudo-diff\'{e}rentiel
matriciel à symbole opérateur,
on montre l'existence de développements
de type BKW pour les valeurs propres et les
fonctions propres de }$P${\small .
Title:
Vectorial
Polarized Manifolds
Authors:
A. Awane, A.Chkiriba,
M.Goze, E. Azizi and M. Bent Bah
Comments:
11 pages, no figures
Abstract:
We
introduce and develop the notion of vectorial
polarized manifolds, some properties of
this last structure and various vectorial
Hamiltonian mappings in the case of polarized
Poisson manifolds and a variety of vectorial
Hamiltonian mappings associated to diverse
vectorial polarized systems in dimension
$\leq 4$ are given.
Keywords:Hamiltonian systems,Poisson manifolds,
symplectic structures. Generalized Hamiltonian
Dynamics of Nambu.
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Title:
Generalized Monodromy Matrix of Two Dimensional
String Effective Action
Authors:
T.Lhallabi, A.Moujib
Comments:
6 pages, no figures
Abstract:
We study the $O(d,d)/O(d)\times O(d)$ coset
reformulation of two-dimensional string
effective action. We construct the generalized
Monodromy Matrix ${\mathcal{\hat{M}}}\left(
\omega \right) $ for $O(d,d)$ string effective
action by using general integrability conditions
and T-duality group properties.
Keywords: T-duality Symmetries, Integrable
models, Monodromy Matrix
Title:
The
Non-linear dynamics and Non-linear bias
for galaxy formation in Redshift Space
Authors:
El Yamani Diaf
Comments:
13 pages, 3 figures
Abstract:
We
measure the $\beta$ parameter using the
quadrupole to monopole ratio from power
spectrum and compare with the true asymptotic
value $\beta\simeq \f{\Omega^{0.6}}{b}$
we get that there is an agreement in the
values of theses two quantities. In addition,
we have studied the non-linear dynamics
and non-linear bias of galaxies. We done
it in two ways: Theoretically and using
N-body simulation. We find excellent agreement
in both theory and GIF simulation. In this
case, we can see clearly how the non-linear
effghect, redshift distortion and non-linear
bias evolves in real and redshift space.
keys words: cosmology: theory - galaxies:
redshift distortion - galaxies: Non-linear
(bias $\&$ dynamics), large-scale structure
of Universe- galaxies: GIF simulation and
theory.
Title:
Théorie
des Cordes Twistorielles et Supergravité
Conforme ${\mathcal{N}}=4,{D}=4$
Authors:
L.B Drissi, H.Jehjouh,
E.H Saidi
Comments:
33 pages, no figures
Abstract:
Ce travail de synthèse traite la
théorie des cordes twistorielle qui
découle de la fusion entre la théorie
des cordes et la géométrie
twistorielle. Cette théorie admet
deux versions : la corde ouverte twistorielle
et le modèle B dans ${\mathbb{CP}}^{3|4}$.
L'étude explicite des opérateurs
vertex de ces deux alternatives tantôt
en termes des twisteurs, tantôt en
termes des états de l'espace \ ${\mathbb{R}}^{1,3}$
nous mène à deux spectres
qui s'avèrent équivalents
contenant également les états
physiques de la supergravité conforme
${\mathcal{N}}=4,{D}=4$ . Cette étude
présente aussi les techniques de
base de l'extension de la symétrie
miroir des supervariétés de
CY que nous appliquons à quelques
supergéométries.
Title:
Invariant k-Symplectic Structures on Principal
$S^{1}$-Bundles
Authors: A.Awane and
M.Rahbi
Comments: 6 pages, no figures
Abstract:
The aim of this work is to study invariant
k-symplectic structures on the total space
of a principal bundle of structural group
the circle $S^{1}$ in order to provide further
examples of k-symplectic manifolds. We show
that the existence of such structures gives
rise to some constraint relations on the topology
of the base space.
Keywords: k-symplectic structure, principal
fibre bundle, torus-bundle, $S^{1}$-bundle.
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Title:
Approche
Hamiltonienne des Systèmes des 2- Formes
Authors: A.Awane and
A. Chkiriba
Comments: 13 pages, no figures
Abstract:
We give various aspects of Hamilonian mappings
associated to the $k-$symplectic structures
and also to a non degenerate systems of closed
two forms.
Keywords: Hamiltonian systems, symplectic
structures. Generalized Hamiltonian Dynamics
of Nambu.
Title:
On
the Effectiveness of Variables Physical Properties
on the Transient Hydromagnetic Couette-Poiseuille
Flow
Authors: Hazem Ali Attia
Comments: 7 pages, 8 figures
Abstract:
The Transient
hydromagnetic Couette-Poiseulle flow and heat
transfer of an electrically conducting fluid is
studied in the presence of a transverse uniform
magnetic field with variable physical properties.
The viscosity and thermal conductivity of the
fluid are assumed to vary with temperature. The
fluid is subjected to a constant pressure gradient
and an external uniform magnetic field perpendicular
to the plates which are kept at different but
constant temperatures. The effect of the magnetic
field, the temperature dependent viscosity and
thermal conductivity on both the velocity and
temperature fields is reported.
Keywords: Fluid dynamics, magnetohydrodynamics,
parallel channel flow, magnetic field, Couette
flow, Couette-Poiseulle, heat transfer, steady
flow, unsteady flow.
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© African Journal of Mathematical Physics |
