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Articles Title
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Abstract
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A Review of Leading Quantum
Gravitational Corrections to Newtonian Gravity
Arif Akhundov and Anwar Shiekh
Full text: Acrobat
PDF (649 KB)
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In
this review we present the theoretical background for treating General
Relativity as an effective field theory and focus on the concrete results
of such a treatment. As a result we present the calculations of the
low-energy leading gravitational corrections to the Newtonian potential
between two sources.
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Radiation Reaction at Extreme
Intensity
Richard T. Hammond
Full text: Acrobat
PDF (165 KB)
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The
radiation reaction force is examined for an idealized short pulse of
electromagnetic radiation and for a plane wave. Exact solutions (without radiation
reaction) are discussed, the total radiated power is calculated. A new and
simpler approach to the approximate form of the equation of motion is
presented that automatically removes the runaway solutions. Finally,
analytical solutions are presented for the equations of motion that include
the radiation reaction forces in the very high intensity regime. A
classical scattering angle is defined and it shows that the electron is scattered in a small
cone in the forward direction. The radiation reaction corrections to this
angle are also considered.
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Super-Light Electromagnetic
Wave With Longitudinal And Transversal Modes
M.M. Kononenko
Full text: Acrobat
PDF (177 KB)
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The
transformation converting equations invariant under Lorentz into the
equations invariant under Galileo is obtained. On this basis:(1) the
super-light electromagnetic wave with longitudinal and transversal modes is
found out; (2) it is shown the wave velocity coincides with that of de
Broglie's wave; (3) the connection between Maxwell's electrodynamics and
Shr\"{o}dinger's equation is established; (4) structural elements of
space are discovered and ``a horizon of visibility'' is found. It is shown Bell's inequalities
and the principle of the light speed constancy are based on the SRT
artifact and ``Einstein's local realism'' is determined by the wave
referred above. Objectivity of results for quantum and classical objects is
discussed.
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Non Commutative Geometry
Constraints and the Standard Renormalization Group Approach: Two Doublets
Higgs Model as An Example.
N.Mebarki and M.Harrat
Full text: Acrobat
PDF (210 KB)
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The
Chamssedine-Fr\"{o}hlich Approach to Noncommutative Geometry (NCG) is extended
and applied to the reformulation of the two doublets Higgs model. The Fuzzy
mass, coupling and unitarity relations are derived. It is shown that the
latter are no more preserved under the renormalization group equations
obtained from the standard quantization method. This suggests to look for
an appropriate NCG quantization procedure.
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Hamilton-Jacobi Formulation
of a Non-Abelian Yang-Mills Theories
W. I. Eshraim and N. I. Farahat
Full text: Acrobat
PDF (126 KB)
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A
non-Abelian theory of fermions interacting with gauge bosons is treated as
a constrained system using the Hamilton-Jacobi approach. The equations of
motion are obtained as total differential equations in many variables. The
integability conditions are satisfied, and the set of equations of motion
is integrable. A comparison with Dirac's method is done
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Physical Form of The
Clustering Parameter And Gravitational Galaxy Clustering
Sajad Masood , Manzoor A Malik, Shakeel Ahmad and N. A.
Rather
Full text: Acrobat
PDF (195 KB)
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A
theory for a system clustering under gravity is developed for the
clustering parameter b(n,T), in terms of a partial differential equation
using thermodynamic technique.
Various solutions of the differential equation relate b(n,T) with
density n and temperature T of the gravitating system. The physical validity of various
solutions of b(n,T) on the basis of certain boundary conditions and
probability density distribution function is discussed. Results indicate that the clustering
parameter depends on the specific combination nT^{-3}. The theory also provides a new insight
into gravitational clustering.
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Penrose Model Potential,
Compared With Coleman- Weinberg Potential for Early Universe Scalar
Evolution
A.W. Beckwith
Full text: Acrobat
PDF (174 KB)
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We
present evidence in terms of a D'Alembertain operator acting on a scalar field
minus the first derivative of a potential system, with respect to an inflaton
scalar field, that the Penrose model as outlined as an alternative to
cosmological big crunch models gives us emergent behavior for an inflaton scalar
field in early universe cosmological models. This is in contrast to the
Coleman-Weinberg potential which in low temperature conditions is always presenting
almost non existent emergent scalar fields. This permits us to state that
Penrose's cyclic universe model in its initial conditions gives us scalar
field dynamics consistent with emergent scalar fields which die out quickly
as temperature drops after the onset of inflation. We make no attempt to
find the particulars of the conformal mapping which allows the alternative
to the big crunch Penrose (2007) lectured upon in the inaugural meeting of
the IGC at Penn
State.
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Increasing Effective
Gravitational Constant In Fractional Add Brane Cosmology
El-Nabulsi Ahmad Rami
Full text: Acrobat
PDF (136 KB)
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Arkani--Hamed--Dimopoulos--Dvali
brane model with time--increasing scaling gravitational constant is
constructed within the framework of fractional action--like variational
approach with one positive parameter `\alpha'.
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A Two-Dimensional Discrete
Mapping with C^{Infinity} Multifold Chaotic Attractors
Zeraoulia Elhadj and J. C. Sprott
Full text: Acrobat
PDF (638 KB)
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This
paper introduces a two-dimensional, C^{\infinity} discrete bounded map
capable of generating "multi- fold" strange attractors via
period-doubling bifurcation routes to chaos.
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Bosons-Parafermions
Wess-Zumino Model
L. Maghlaoui and N. Belaloui
Full text: Acrobat
PDF (159 KB)
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A
Wess-Zumino model in terms of bosons and parafermions of order p=2 is
investigated.\,We show that the parasupercharges associated to the
parasupersymmetric transformations satisfy the p=2 trilinear relations. The
closure of the transformations algebra is established with a trilinear
product rule for the fermionic elements. Finally, we verify that these
parasupercharges are really the generators of the parasupersymmetric
transformations.
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Geometrodynamics of
Information on Curved Statistical Manifolds and Its Applications to Chaos
C. Cafaro and S. A. Ali
Full text: Acrobat
PDF (256 KB)
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A
novel information-geometrodynamical approach to chaotic dynamics (IGAC) on curved
statistical manifolds based on Entropic Dynamics (ED) is presented and a
new definition of information geometrodynamical entropy (IGE) as a measure
of chaoticity is proposed. The general classical formalism is illustrated
in a relatively simple example. It is shown that the hyperbolicity of a
non-maximally symmetric 6N-dimensional statistical manifold {M}_{s}
underlying an ED Gaussian model describing an arbitrary system of 3N
degrees of freedom leads to linear information-geometric entropy growth and
to exponential divergence of the Jacobi vector field intensity, quantum and
classical features of chaos respectively. An information-geometric analogue
of the Zurek-Paz quantum chaos criterion in the classical reversible limit
is proposed. This analogy is illustrated applying the IGAC to a set of n-uncoupled
three-dimensional anisotropic inverted harmonic oscillators characterized
by a Ohmic distributed frequency spectrum.
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Stochastic Measures and
Modular Evolution in Non-Equilibrium Thermodynamics
Enrique Hernandez-Lemus, and Jesus
K. Estrada-Gil
Full text: Acrobat
PDF (239 KB)
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We
present an application of the theory of stochastic processes to model and
categorize non-equilibrium physical phenomena. The concepts of uniformly
continuous probability measures and modular evolution lead to a systematic
hierarchical structure for (physical) correlation functions and
non-equilibrium thermodynamical potentials. It is proposed that macroscopic
evolution equations (such as dynamic correlation functions) may be obtained
from a non-equilibrium thermodynamical description, by using the fact that
extended thermodynamical potentials belong to a certain class of
statistical systems whose probability distribution functions are defined by
a {\it stationary measure}; although a measure which is, in general, {\sl
different} from the equilibrium Gibbs measure. These probability measures
obey a certain hierarchy on its stochastic evolution towards the most
probable (stationary) measure. This in turns defines a convergence sequence.
We propose a formalism which considers the mesoscopic stage (typical of
non-local dissipative processes such as the ones described by extended
irreversible thermodynamics) as being governed by stochastic dynamics due
to the effect of non-equilibrium fluctuations. Some applications of the
formalism are described.
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Beltrami Flow of an Unsteady
Dusty Fluid between Parallel Plates in Anholonomic Co-Ordinate System
B.J.Gireesha, C.S.Bagewadi and
C.S.Vishalakshi
Full text: Acrobat
PDF (242 KB)
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An
analytical study of Beltrami flow of viscous dusty fluid between two
parallel plates has been studied. The flow is due to influence of movement
of plates. Flow analysis is carried out using differential geometry
techniques and exact solutions of the problem are obtained using Laplace
Transform technique also which are discussed with the help of graphs drawn for
different values of Reynolds number. Further the expressions for
skin-friction are obtained at the boundaries.
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Factorization Method and
Solution of the Non- Central Modified Kratzer Potential
J. Sadeghi and B. Pourhassan
Full text: Acrobat
PDF (175 KB)
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In
this paper, we study the Schr\"odinger equation with a non - central
modified Kratzer potential plus a ring – shaped like potential, which is
not spherically symmetric. Thus, the standard methods for separation of
variables do not quite apply. However we are able to separate variables
using a simple extension of the standard method, which leads to solutions
in the associated Laguerre function for the radial part and Jacobi
polynomials for the polar angle part. We also introduce an interesting pair
of first order ladder operators, which allow us to generate the energy eigenvalues
for all states of the system. The obtained results show that the lack of
spherical symmetry removes the degeneracy of second quantum number m which
completely expected.
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Discrete Self-Similarity
between Rr Lyrae Stars And Singly-Excited Helium Atoms
Robert L. Oldershaw
Full text: Acrobat
PDF (137 KB)
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Classical
variable stars called RR Lyrae stars have pulsating outer envelopes
constituted of excited atoms. Here we demonstrate that the qualitative and
quantitative properties of RR Lyrae variables and one subclass of their
atomic scale constituents: singly-excited helium atoms undergoing transitions
between Rydberg states, share a remarkable degree of self-similarity. In
terms of masses, radii, oscillation periods, morphologies and kinematics
the stellar and atomic analogues obey a simple set of discrete self-similar
scaling equations. The concept of stellar/atomic self-similarity may prove
useful in the search for a deeper understanding of both stellar and atomic
systems.
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Brownian Dynamics of
Nanoparticles Moving Near a Fluctuating Membrane
A. Bendouch, M. Benhamou, and H.
Kaidi
Full text: Acrobat
PDF (187 KB)
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This
work deals with Brownian dynamics study of small nanoparticles moving near
an attractive penetrable fluid membrane. As consequence, these particles
are pushed towards the interface, under a change of a suitable physical
parameter, such as temperature, pressure or membrane environment. For
simplicity, we assume that the particle size is small enough in comparison
to the roughness of the membrane. In addition, the particles are supposed
to be of very low density (their mutual interactions can be ignored). Then,
the only remaining interaction is a mean-force external potential computed exactly
in some recent work. The latter that originates from the strong membrane
undulations, is a function of the perpendicular distance $z$. Brownian
dynamics are studied through the time particle density, which solves the
Smoluchowski equation. This density is determined exactly around the fluid
membrane, where the essential of phenomenon takes place. In particular, far
from the interface, the beads diffuse as usual. But inside the thermal
fluctuations region, the Brownian particles diffuse and effectuate small
oscillations, with a frequency \omega scaling as \omega \thicksim \kappa
^{3/8}, where \kappa accounts for
the bending rigidity constant of the membrane. We emphasize that the
present Brownian dynamics study reveals the existence of a characteristic
time \tau \thicksim \kappa ^{-3/4}, which can be interpreted as the time
beyond which the particles reach their final equilibrium state. For early
times \left( t<\tau \right) , however, the particles are out equilibrium.
After a long time \left( t>\tau \right) , the beads reach their final
equilibrium state, and occupy new holes and valleys.\ Finally, this work
must be considered as a natural extension of a recent one that was
concerned with the static study of the colloidal organization in contact
with a fluctuating fluid membrane.
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Influence of Third Order
Perturbation on Heisenberg Hamiltonian Of Thick Ferromagnetic Films
P. Samarasekara
Full text: Acrobat
PDF (197 KB)
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The
effect of third order perturbation on the classical Heisenberg Hamiltonian
of thick ferromagnetic has been investigated for the first time. Energy of
thick films with layers up to 10000 has been plotted for sc(001) and fcc(001)
ferromagnetic compounds. Unlike the second order perturbation, the third
order perturbation does not increase the total energy by any considerable
amount. For the thicknesses approximately N=45 and 40, the anisotropy
energy is small for sc(001) and fcc(001), respectively, indicating that the
energy required to rotate from easy to hard direction is really small at
theses thicknesses. The energy curves of sc (001) and fcc(001) with N=10000
have been flattened by reducing the smooth part of the curve compared with
those of second order perturbation. The angle between the easy and hard direction
is 97.4^{0} and 32.45^{0 }for sc(001) and fcc(001) thick film with N=10000,
respectively. The overshooting parts began to appear after introducing
second or third order perturbation, and hence the angle between easy and
hard directions is not 90^{0} in the overshooting part of curves. The third
and second order perturbation vanish at \theta =0^{0} and 90^{0}
directions.
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Viscous Dusty Fluid Flow with
Constant Velocity Magnitude
Siddabasappa, Venkateshappa,
Rudraswamy, Gopinath
Full text: Acrobat
PDF (467 KB)
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We
consider the viscous dusty fluid, where the velocity of the dust particle
is everywhere parallel to that of the fluid with velocity magnitude of the
fluid is constant along each individual streamline. Also it is assumed that
number density of the dust particle is constant and the dust particles are
uniform in size and shape and bulk concentration of the dust is small.
Hodograph and Legendre transform of stream function is employed to get the solutions
and the geometry of streamlines for these flows by using the resulting
partial differential equations when the Jacobian is zero and nonzero cases.
In each case the variation of pressure is analyzed graphically.
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The Influence of Long-Range
Interaction on Critical Behavior of Some Alloys
S. V. Belim
Full text: Acrobat
PDF (124 KB)
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The
critical behavior of some alloys are analyzed within the framework of
Heisenbergs model with long-range interaction. On based experimental values
of the critical exponent \gamma we calculate the value of paerameter of
long-range interaction.
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