|

ISSN 1729-5254
For Issues (1-6), please contact the editor at:
info[AT]ejtp.com.
Volume 2, Issue 7 (August
2005)
Full text: Acrobat
PDF (520 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Application of Coadjoint Orbits in the Thermodynamics of
Non-Compact Manifolds.
V. V. Mikheyev; I. V.
Shirokov
Full text: Acrobat PDF
(197 KB)
|
Method
of the solution of the main problem of homogeneous spaces thermodynamics
for non-compact spaces in the case of non-compact Lie groups is presented
in the article. The method is based on the method of coadjoint orbits. The
formula that allows efficiently evaluate heat kernel on non-compact spaces
is obtained. The method is illustrated by non-trivial example.
|
|
2
|
The Boundary Conditions
Geometry in Lattice-Ising Model
You-gang Feng
Full text: Acrobat PDF
(126 KB)
|
We
found that the differential topology of the lattice-system Ising model
determines whether there can be the continuous phase transition, The
geometric topology of the space the lattice-system is embedded in
determines whether the system can become ordered. If the system becomes
ordered it may not admit the continuous phase transition. The
spin-projection orientations are strongly influenced by the geometric
topology of the space the lattice system is embedded in.
|
|
3
|
Simulation of
Ginger EPR Spectra Obtained by X-Irradiation: Quantum Approach
S. Laachir; M. Moussetad; R. Adhiri; A. Fahli; M.
Aboulfatah; M. Mikou
Full text: Acrobat PDF
(139 KB)
|
The
ginger sample has been exposed to X-rays at cumulative doses. The
foodstuffs irradiation is used in particular to improve their hygienic
qualities and increase their shelf lives. This process has been approved by
various international organizations: FAO -- AIEA -- WHO. In the present work, we
propose to reproduce by simulation, based on a quantum approach, of the ESR
(Electron Spin Resonance) spectra. The semi-classical approach is valid for
a simple system, but not for a complex system such as an atom with
hyperfine structure. In this case a quantum approach, based on spin
Hamiltonian, is essential to interpret the ESR spectra. The main result is
that the simulated spectra are in good agreement with the experimental ones
obtained before and after irradiation.
|
|
4
|
Quantum AdS1+3
Black Holes with Effective Cosmological Constant
El-Nabulsi Ahmad Rami
Full text: Acrobat PDF
(249 KB)
|
A
quantum AdS1+3 massive and massless black holes with effective
cosmological constant induced from non-minimal coupling and supergravities
arguments are constructed and discussed in details.
|
Volume 2, Issue 8
(December 2005)
Full text: Acrobat
PDF (704 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Fractional Unstable Euclidean Universe.
El-Nabulsi Ahmad Rami
Full text: Acrobat PDF
(174 KB)
|
Despite
common acceptance of Big Bang hypothesis among most cosmologists,
nonetheless there are criticisms from a small number of theorists partly
supported by astronomy observation suggesting that redshift data could not
always be attributed to cosmological expansion. In this paper, a new
approach to cosmology fractional calculus has been developed that we hope
will attract attention from astrophysicists and cosmologists because of the
way it challenges the conventional big bang framework.
|
|
2
|
Parametric
Relationships Among Some Phenomenological Non-Relativistic Hadronic
Potentials
Teik-Cheng Lim
Full text: Acrobat PDF
(153 KB)
|
In
recent years, parametric relationships between interatomic potential energy
functions have been developed in the realm of molecular chemistry and
condensed matter physics. However, no parametric relationships have been
developed so far among intra-atomic potentials. As an extension of previous
works into the realm of intra-atomic potentials, we herein consider the
possibility that hadronic potentials can be interrelated via their
parameters. Hadronic potentials give quantitative description of interquark
energy in terms of interquark distance, hence understanding how each
potential function influences the theoretical modeling can be sought via
knowledge of interrelationship amongst the potentials parameters.
Phenomenological non-relativistic hadronic potentials are related amongst
the mixed-powerlaw potential themselves, and with the Logarithmic
potentials using calculus. Exact nonlinear relationships were obtained
between the parameters whereby the interquark distance is included as one
of the variables. It is also demonstrated that, when the interquark
distance in the parametric relationships is assigned a fixed value of
unity, the parametric relationships remain valid from the plotted potential
energy curves..
|
|
3
|
Non Linear
Assessment of Musical Consonance
SLluis Lligo˜na Trulla, Alessandro Giuliani,
Giovanna Zimatore, Alfredo Colosimo and Joseph P. Zbilut
Full text: Acrobat PDF
(326 KB)
|
The
position of intervals and the degree of musical consonance can be
objectively explained by temporal series formed by mixing two pure sounds
covering an octave. This result is achieved by means of Recurrence
Quantification Analysis (RQA) without considering neither overtones nor
physiological hypotheses. The obtained prediction of a consonance can be
considered a novel solution to Galileo's conjecture on the nature of
consonance. It constitutes an objective link between musical performance
and listeners hearing activity..
|
|
4
|
Conditions
for the Generation of Causal Paradoxes from Superluminal Signals
Giuseppe Russo
Full text: Acrobat PDF
(203 KB)
|
We
introduce a simple method to illustrate how the Lorentz transformation lead
to causal loop paradoxes when they are applied to superluminal velocities.
|
Volume 3, Issue 9
(February 2006)
Full text: Acrobat
PDF (1,206 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Spinning of Particles in Schwarzschild-de-Sitter and
Schwarzschild-Anti-de-Sitter Space-Times with `Effective Cosmological
Constant'.
El-Nabulsi Ahmad Rami
Full text: Acrobat PDF
(132 KB)
|
Spinning
of particles in SdS and SAdS space-times with effective cosmological
constant is discussed in details. It is shown that the equilibrium
conditions are independent of the spin of the test particles and are
satisfied only for particular conditions relating the Einstein's
cosmological constant with the ultra-light masses implemented in the theory
from supergravities arguments and non-minimal coupling.
|
|
2
|
How S-S' di Quark
Pairs Signify an Einstein Constant Dominated Cosmology, and Lead to New
Inflationary Cosmology Physics
A. W. Beckwith
Full text: Acrobat PDF
(335 KB)
|
We
review the results of a model of how nucleation of a new universe occurs,
assuming a di quark identification for soliton-anti soliton constituent
parts of a scalar field. Initially, we employ a false vacuum potential
system; however, when cosmological expansion is dominated by the Einstein
cosmological constant at the end of chaotic inflation, the initial di quark
scalar field is not consistent w.r.t a semi classical consistency condition
we analyze as the potential changes to the chaotic inflationary potential
utilized by Guth. We use Scherrer's derivation of a sound speed being zero
during initial inflationary cosmology, and obtain a sound speed approaching
unity ~as the slope of the scalar field moves away from a thin wall
approximation. All this is to aid in a data reconstruction problem of how
to account for the initial origins of CMB due to dark matter since
effective field theories as presently constructed require a cut off value
for applicability of their potential structure. This is often at the cost
of, especially in early universe theoretical models, of clearly defined
baryogenesis, and of a well defined mechanism of phase transitions.
|
|
3
|
Vectorial Lorentz
Transformations
Jorge A. Franco R.
Full text: Acrobat PDF
(403 KB)
|
We
have noticed in relativistic literature that the derivation of Lorentz
Transformations (LT) usually is presented by confining the moving system O'
to move along the X-axis, namely, as a particular case of a more general
movement. When this movement is generalized different transformations are
obtained (which is a contradiction by itself) and a hidden vectorial
characteristic of time is revealed. LT have been generalized in order to
solve some physical and mathematical inconsistencies, such as the dissimilar
manners (transversal, longitudinal) the particle's shape is influenced by
its velocity and LT's inconsistency with Maxwell equations when in its
derivation the pulse of light is sent perpendicular to the displacement of
the moving system O'. Unlike the canonical derivation of LT, in the
undertaken development of the generalized LT, assumptions were not used.
Practical applications of generalized Vectorial Lorentz Transformations
(VLT) were undertaken and as outcome a new definition of Local Lorentz
Transformations (LLT) of magnitudes appeared. As another consequence, a
characteristic and unique scaling Lorentz factor was obtained for each
magnitude Given this, a dimensional analysis based upon these Lorentz
factors came up. In addition, dynamical transformations were obtained and a
new definition of mass was found.
|
|
4
|
Lattice Dynamics of
Hydrogen Interstice Co_{0.92}Fe_{0.08}
C. Kalai Arasi, R. John Bosco Balaguru, S. Alfred Cecil
Raj, and N. Lawrence
Full text: Acrobat PDF
(465 KB)
|
Lattice
dynamics of hydrogen interstice in the binary alloy Co_{0.92} Fe _{0.08}
has been carried out to calculate the phonon dispersions along the [100],
[110], [111] directions. The phonon density of states, variation of
specific heat capacity and Debye's temperature with temperature are also
calculated. A reasonably good agreement is found between the calculated and
other theoretical and experimental results. The mean square displacement
(MSD) of atoms surrounding the interstitial hydrogen atom is reported along
with the defect modes.
|
|
5
|
Petrov
classification of the conformal tensor
M. A. Acevedo M., M. Enciso-Aguilar, and J. Lopez-Bonilla
Full text: Acrobat PDF
(110 KB)
|
We
exhibit a flux diagram in its tensorial and Newman-Penrose representations
for the Petrov classification.
|
|
6
|
On Inflation
Potentials in Randall-Sundrum Braneworld Model
M.Bennai, H.Chakir, and Z.Sakhi
Full text: Acrobat PDF
(168 KB)
|
We
study the inflationary dynamics of the universe in the Randall-Sandrum
typeII Braneworld model. We consider both an inverse-power law and
exponential potentials and apply the Slow-Roll approximation in high energy
limit to derive analytical expression of relevant inflationary quantities.
An upper bound for the coupling constant was also obtained and a numerical
value of perturbation spectrum is calculated in good agreement with
observation.
|
|
7
|
Considerations About
The Anomalous Efficiency Of Particular Thermodynamic Cycles
Leonardo Chiatti
Full text: Acrobat PDF
(292 KB)
|
Some
years ago Vignati (refs. 1, 2, 3) showed that, under some particular
circumstances (inter alia isobaric processes connected through internal
heat exchangers), the efficiency of an Ericsson cycle involving a real gas
can exceed the Carnot limit \eta_{C} , in contradiction with the second
principle of thermodynamics. However, the convergence of Vignati's
algorithm, giving the temperature difference between the intermediate heat
exchangers, has not yet been proved. In particular, it isn't clear, if the
number of intermediate heat exchangers infinitely increases, the condition
of a total (perfect) heat recovery may be asymptotically approximated. This
remark is relevant because the claimed anomalous efficiencies appear only
in the limit of a perfect heat recovery. Considering a suitable counterexample,
we prove that, in general, the residual heat discharged on the external
sources does not vanish in that limit, even when the isobars exchange the
same amount of heat. Therefore the violation of the second law inferred
from Vignati's calculation is merely apparent, being referred to a
situation which is not (in principle) physically realisable. The essentials
of the Vignati's argument are then applied to an Ericsson cycle involving
an ideal gas undergoing chemical reactions. Again, no contradiction arises
with the second principle.
|
Volume 3, Issue 10 (April
2006), Majorana Issue (Editor: Ignazio Licata)
Full text: Acrobat
PDF (1,988 KB)
|
Number
|
Articles Title
|
Abstract
|
|
|
Majorana Imoact on Contemporary Physics
Ignazio
Licata
Full text: Acrobat
PDF (14 KB)
|
Editorial
Note
|
|
1
|
The Scientific Work Of Ettore Majorana: An Introduction
Erasmo Recami
Full text: Acrobat
PDF (113 KB)
|
A
Brief bibliography of the scientific work of Ettore Majorana has been
discussed.
|
|
2
|
On the Hamiltonian
Form of Generalized Dirac Equation for Fermions with Two Mass States
Sergey. I. Kruglov
Full text: Acrobat
PDF (126 KB)
|
Dynamical
and non-dynamical components of the 20-component wave function are
separated in the generalized Dirac equation of the first order, describing
fermions with spin 1/2 and two mass states. After the exclusion of the
non-dynamical components, we obtain the Hamiltonian Form of equations.
Minimal and non-minimal electromagnetic interactions of particles are
considered here.
|
|
3
|
Majorana Equation
and exotics: Higher Derivative Models, Anyons and Noncommutative Geometry
Mikhail S. Plyushchay
Full text: Acrobat
PDF (199 KB)
|
In
1932 Ettore Majorana proposed an infinite-component relativistic wave
equation for particles of arbitrary integer and half-integer spin. In the
late 80s and early 90s it was found that the higher-derivative geometric
particle models underlie the Majorana equation, and that its (2+1)-dimensional
analogue provides with a natural basis for the description of relativistic
anyons. We review these aspects and discuss the relationship of the
equation to the exotic planar Galilei symmetry and noncommutative geometry.
We also point out the relation of some Abelian gauge field theories with
Chern-Simons terms to the Landau problem in the noncommutative plane from
the perspective of the Majorana equation.
|
|
4
|
Wave Equations,
Renormalization and Meaning of the Planck's Mass: Some Qualitative
Considerations
Leonardo Chiatti
Full text: Acrobat
PDF (131 KB)
|
The five-dimensional
version of the quantum relativistic Klein-Gordon wave equation is assumed
to be a more fundamental description for the dynamics of the single
particle without spin. The meaning of the renormalization procedure in QFT
and the Planck's mass one are briefly discussed from this point of view.
|
|
5
|
Nonlinear Field
Equations and Solitons as Particles
Attilio Maccari
Full text: Acrobat
PDF (346 KB)
|
Profound
advances have recently interested nonlinear field theories and their exact
or approximate solutions. We review the last results and point out some
important unresolved questions. It is well known that quantum field
theories are based upon Fourier series and the identification of plane
waves with free particles. On the contrary, nonlinear field theories admit
the existence of coherent solutions (dromions, solitons and so on).
Moreover, one can construct lower dimensional chaotic patterns,
periodic-chaotic patterns, chaotic soliton and dromion patterns. In a
similar way, fractal dromion and lump patterns as well as stochastic
fractal excitations can appear in the solution. We discuss in some detail a
nonlinear Dirac field and a spontaneous symmetry breaking model that are
reduced by means of the asymptotic perturbation method to a system of
nonlinear evolution equations integrable via an appropriate change of
variables. Their coherent, chaotic and fractal solutions are examined in
some detail. Finally, we consider the possible identification of some types
of coherent solutions with extended particles along the de Broglie-Bohm
theory. However, the last findings suggest an inadequacy of the particle
concept that appears only as a particular case of nonlinear field theories
excitations.
|
|
6
|
The Quantum
Character of Physical Fields.
Foundations of
Field Theories
Ludmila. I. Petrova
Full text: Acrobat
PDF (161 KB)
|
The
existing field theories are based on the properties of closed exterior
forms, which are invariant ones and correspond to conservation laws for
physical fields. Hence, to understand the foundations of field theories and
their unity, one has to know how such closed exterior forms are obtained.
In the present paper it is shown that closed exterior forms corresponding
to field theories are obtained from the equations modeling conservation
(balance) laws for material media. It has been developed the evolutionary
method that enables one to describe the process of obtaining closed
exterior forms. The process of obtaining closed exterior forms discloses
the mechanism of evolutionary processes in material media and shows that
material media generate, discretely, the physical structures, from which
the physical fields are formed. This justifies the quantum character of
field theories. On the other hand, this process demonstrates the connection
between field theories and the equations for material media and points to
the fact that the foundations of field theories must be conditioned by the
properties of material media. It is shown that the external and internal
symmetries of field theories are conditioned by the degrees of freedom of
material media. The classification parameter of physical fields and
interactions, that is, the parameter of the unified field theory, is
connected with the number of noncommutative balance conservation laws for
material media.
|
|
7
|
Relativistic
Causality and
Quasi
-Orthomodular Algebras
Renato.Nobili
Full text: Acrobat
PDF (218 KB)
|
The concept of
fractionability or decomposability in parts of a physical system has its
mathematical counterpart in the lattice--theoretic concept of
orthomodularity. Systems with a finite number of degrees of freedom can be
decomposed in different ways, corresponding to different groupings of the
degrees of freedom. The orthomodular structure of these simple systems is
trivially manifest. The problem then arises as to whether the same property
is shared by physical systems with an infinite number of degrees of
freedom, in particular by the quantum relativistic ones. The latter case
was approached several years ago by Haag and Schroer (1962; Haag, 1992) who
started from noting that the causally complete sets of Minkowski spacetime
form an orthomodular lattice and posed the question of whether the
subalgebras of local observables, with topological supports on such
subsets, form themselves a corresponding orthomodular lattice. Were it so,
the way would be paved to interpreting spacetime as an intrinsic property
of a local quantum field algebra. Surprisingly enough, however, the hoped
property does not hold for local algebras of free fields with
superselection rules. The possibility seems to be instead open if the local
currents that govern the superselection rules are driven by gauge fields. Thus,
in the framework of local quantum physics, the request for algebraic
orthomodularity seems to imply physical interactions! Despite its charm,
however, such a request appears plagued by ambiguities and criticities that
make of it an ill--posed problem. The proposers themselves, indeed,
concluded that the orthomodular correspondence hypothesis is too strong for
having a chance of being practicable. Thus, neither the idea was taken
seriously by the proposers nor further investigated by others up to a reasonable
degree of clarification. This paper is an attempt to re--formulate and
well--pose the problem. It will be shown that the idea is viable provided
that the algebra of local observables: (1) is considered all over the whole
range of its irreducible representations; (2) is widened with the addition
of the elements of a suitable intertwining group of automorphisms; (3) the
orthomodular correspondence requirement is modified to an extent sufficient
to impart a natural topological structure to the intertwined algebra of
observables so obtained. A novel scenario then emerges in which local
quantum physics appears to provide a general framework for
non--perturbative quantum field dynamics.
|
|
8
|
Lorentz Invariant
Majorana Formulation of Electrodynamics in the Clifford Algebra Formalism
Tomislav Ivezic
Full text: Acrobat
PDF (143 KB)
|
In
this paper we present a new geometric formulation (Clifford algebra
formalism) of the field equations, which is independent of the reference
frame and of the chosen system of coordinates in it. This formulation deals
with the complex 1-vector \Psi =E-icB (i is the unit imaginary), which is
four-dimensional (4D) geometric generalization of Majorana's complex 3D
quantity \Psi }=E-icB. When the sources are absent the field equations with
the complex \Psi become Dirac-like relativistic wave equations for the free
photon. In the frame of ``fiducial'' observers (the observers who measure
fields are at rest) and in the standard basis the component form of the
field equations with 4D \Psi reproduces the component form of
Majorana-Maxwell equations with 3D field \Psi . The important differences
between the approach with the 4D \Psi and that one with the 3D \Psi are
discussed.
|
|
9
|
"
Anticoherent " Spin States via
the Majorana Representation
Jason Zimba
Full text: Acrobat
PDF (400 KB)
|
In
this article we define and exhibit '' anticoherent" spin states, which
are in a sense '' the opposite" of the familiar coherent spin states.
Since the familiar coherent states are as "classical" as spin
states can be, the anticoherent states may turn out to be better candidates
for applications involving non-classical behaviors such as quantum
entanglement. Thanks to the Majorana representation of spinors as 2s-tuples
of points on the Riemann sphere, classes of anticoherent states are easy to
find; the development of such examples also leads us into some curious
geometry involving the perfect solids.
|
|
10
|
Stretching the
Electron as Far as it Will Go
G. W. Semenoff and P. Sodano
Full text: Acrobat
PDF (287 KB)
|
Effects
associated with the existence of isolated zero modes of Majorana fermions
are discussed. It is argued that the quantization of this system necessarily
contains highly extended quantum states and that populating and
depopulating such states by interacting with the quantum system leads to
long-ranged teleportation-like processes. Also leads to spontaneous
violation of fermion parity symmetry. A quasi-realistic model consisting of
a quantum wire embedded in a p-wave superconductor is discussed as an
explicit example of a physical system with an isolated Majorana zero mode.
|
|
11
|
Why do Majorana
Neutrinos Run Faster than Dirac Neutrinos?
Zhi-zhong Xing and He Zhang
Full text: Acrobat
PDF (380 KB)
|
The
\tau-lepton dominance in the one-loop renormalization-group equations
(RGEs) of neutrinos sets a cute criterion to parametrize the 3x3 lepton
flavor mixing matrix U: its elements U_{3i} (for i=1,2,3) should be as
simple as possible. Such a novel parametrization is different from the
``standard" one used in the literature and can lead to greatly
simplified RGEs for three mixing angles and the physical CP-violating
phase(s), no matter whether neutrinos are Dirac or Majorana particles. We
show that the RGEs of Dirac neutrinos are not identical with those of
Majorana neutrinos even if two Majorana CP-violating phases vanish. As the
latter can keep vanishing from the electroweak scale to the typical seesaw
scale, it makes sense to explore the similarities and differences between
the RGE running effects of Dirac and Majorana neutrinos. We conclude that
Majorana neutrinos are in general expected to run faster (i.e., more
significantly) than Dirac neutrinos.
|
|
12
|
Universe Without Singularities
A Group Approach to De Sitter Cosmology
Ignazio Licata
Full text: Acrobat
PDF (162 KB)
|
In
the last years the traditional scenario of ``Big Bang'' has been deeply
modified by the study of the quantum features of the Universe evolution,
proposing again the problem of using ``local'' physical laws on cosmic
scale, with particular regard to the cosmological constant role. The
``group extention'' method shows that the De Sitter group univocally
generalizes the Poincaré group,
formally justifies the cosmological constant use and suggests a new
interpretation for Hartle-Hawking boundary conditions in Quantum Cosmology.
|
|
13
|
Majorana and the
Investigation of Infrared Spectra of Ammonia
Elisabetta. Di Grezia
Full text: Acrobat
PDF (169 KB)
|
An
account is given on the first studies on the physics of ammonia, focusing
on the infrared spectra of that molecule. Relevant contributions from
several authors, in the years until 1932, are pointed out, discussing also
an unknown study by E.Majorana on this topic.
|
|
14
|
Exact Solution of
Majorana Equation via Heaviside Operational Ansatz
Valentino A. Simpao
Full text: Acrobat
PDF (215 KB)
|
In
context of a transformation between Majorana and Dirac wavefunctions, it
suffices to solve the related interactive Dirac problem and then apply the
transformation of variables on the Dirac wavefunction in order to obtain
the Majorana wavefunction of the given Majorana equation. Clearly, this
connection between solutions continues to hold if the free Majorana and
Dirac equations are each coupled to an external gauge field [e.g.,
Electromagnetism] via the minimum coupling prescription. Applying the
formal solution scheme Heaviside Operational Ansatz[heretofore, HOA] put
forward in [ EJTP 1 (2004), 10-16], provides an exact quadrature solution
for the massive minimum-coupled Majorana equation in terms of the solution
of the corresponding massive minimum-coupled Dirac equation.
|
|
15
|
A Logical Analysis
of Majorana’s Papers on Theoretical Physics
A. Drago and S. Esposito
Full text: Acrobat
PDF (161 KB)
|
We
study two celebrated Majorana's papers through a method of investigation
which relies upon the recently recognized distinction between classical
logic and several kinds of non-classical logics, i.e. the failure of the
double negation law. This law fails when a double negated sentence is not
equivalent to the corresponding positive sentence, owing to the lack of
scientific evidence of the latter one. All recognized double negated
sentences inside the text of each paper are listed; the mere sequence of
such sentences giving the logical thread of Majorana's arguing. This one is
recognized to be of the Lagrangian kind, which mixes logical arguing and
mathematical calculation; i.e. the author puts a fundamental problem which
is solved by anticipating the mathematical hypothesis able to solve it, and
then by drawing from this hypothesis the mathematical consequences in order
to reach to desired result. Furthermore the rethoric of presentation used
by Majorana results to be a juridical one, owing to his style of presenting
the laws to which an ideal theoretical physicist has to conform his mind in
order to solve the problem at issue.
|
|
16
|
Four Variations on
Theoretical Physics by Ettore Majorana
Salvatore. Esposito
Full text: Acrobat
PDF (219 KB)
|
An
account is given of some topical unpublished work by Ettore Majorana,
revealing his very deep intuitions and skillfulness in Theoretical Physics.
The relevance of the quite unknown results obtained by him is pointed out
as well.
|
|
17
|
The Majorana Oscillator
Eliano Pessa
Full text: Acrobat
PDF (124 KB)
|
At
present the expression ‘Majorana oscillator’ does not appear to
be in use in theoretical physics. However, the author of this paper heard
it in the Seventies, during private conversations with the late Prof.
B.Touschek. This little contribution tries to explore the possible meanings
of this expression and introduces a new field equation, generalizing the
one already introduced by Majorana himself, which could describe a
hypothetical ‘Majorana oscillator’.
|
|
18
|
Scattering of an
\alpha Particle by a Radioactive Nucleus
Unpublished 1928
Ettore Majorana
Full text: Acrobat
PDF (166 KB)
|
In
the following we reproduce, translated into English, a section of Volumetto
II, a notebook written by Majorana in 1928 when he was still a Physics
student at the University of Rome (see S. Esposito, E. Majorana jr, A. van
der Merwe and E. Recami (eds.) Ettore Majorana: Notes on Theoretical
Physics, Kluwer, New York, 2003). This study was performed by the author
when he was preparing his Thesis work on ``The Quantum Theory of
Radioactive Nuclei'' (unpublished),
whose supervisor was E. Fermi.
S.
Esposito
|
|
19
|
Comments on a Paper
by Majorana Concerning Elementary Particles
David. M. Fradkin
Full text: Acrobat
PDF (145 KB)
|
An
early paper (1932) by Majorana, that has received but scant attention, is
reexamined in light of later developments. This pioneering paper constructs
a relativistically invariant theory of arbitrary spin particles, develops
and utilizes infinite dimensional representations of the homogeneous
Lorentz group, and provides a mass spectrum for elementary particles. The
relevance of Majorana’s approach and results to later and current
research is explained.
Reprinted with permission from the
AMERICAN JOURNAL OF PHYSICS, Volume 34, Issue 4, pp. 314-318. Copyright
1966, American Association of Physics Teachers
We
reproduce here the historical D. M. Fradkin 1966 paper whose role among the
physicists of high energy was decisive; since then espressions like
"Majorana mass", "Majorana spinors" and "Majorana
neutrino" have become usual. The paper is based upon the work Teoria
di Particelle con Momento Intrinseco Arbitrario, translated by Italiam from
Edoardo Amaldi.
Ignazio
Licata
|
Volume 3, Issue 11 (June
2006)
Full text: Acrobat
PDF (2,349 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Non-Minimal Coupling Effects of the Ultra-Light Particles on
Photons Velocities in the Radiation Dominated Era of the Universe.
El-Nabulsi Ahmad Rami
Full text: Acrobat
PDF (179 KB)
|
The
effect of the ultra-light masses of the order of the Hubble constant,
implemented in Einstein's field equations from non-minimal coupling and
supergravities arguments, on photons velocities in the radiation dominated
epoch of the Universe within the framework of non-minimal interaction of
electromagnetic fields with gravity is developed and discussed in details.
|
|
2
|
A Toy Model of
Financial Markets
J. P. Singh and S. Prabakaran
Full text: Acrobat
PDF (217 KB)
|
Several
techniques of fundamental physics like quantum mechanics, field theory and
related tools of non-commutative probability, gauge theory, path integral
etc. are being applied for pricing of contemporary financial products and
for explaining various phenomena of financial markets like stock price
patterns, critical crashes etc.. In this paper, we apply the well
entrenched methods of quantum mechanics and quantum field theory to the
modeling of the financial markets and the behavior of stock prices. After
defining the various constituents of the model including creation &
annihilation operators and buying & selling operators for securities,
we examine the time evolution of the financial markets and obtain the
Hamiltonian for the trading activities of the market. We finally obtain the
probability distribution of stock prices in terms of the propagators of the
evolution equations.
|
|
3
|
Rayleigh process
and matrix elements for the one-dimensional harmonic oscillator
J.H. Caltenco, J.L. López-Bonilla, and J. Morales
Full text: Acrobat
PDF (119 KB)
|
We
show that, the matrix elements <|{e^{-\gamma[x]}|n> for the
one-dimensional harmonic oscillator have application in Markov process theory,
permitting thus to resolve the Fokker-Planck equation for the
two-dimensional probability density corresponding to Rayleigh case.
|
|
4
|
Identical
synchronization in chaotic jerk dynamical systems
Vinod Patidar and K. K. Sud
Full text: Acrobat
PDF (942 KB)
|
It
has been recently investigated that the jerk dynamical systems are the
simplest ever systems, which possess variety of dynamical behaviors
including chaotic motion. Interestingly, the jerk dynamical systems also
describe various phenomena in physics and engineering such as electrical
circuits, mechanical oscillators, laser physics, solar wind driven
magnetosphere ionosphere (WINDMI) model, damped harmonic oscillator driven
by nonlinear memory term, biological systems etc. In many practical
situations chaos is undesirable phenomenon, which may lead to irregular
operations in physical systems. Thus from a practical point of view, one would
like to convert chaotic solutions into periodic limit cycle or fixed point
solutions. On the other hand, there has been growing interest to use chaos
profitably by synchronizing chaotic systems due to its potential
applications in secure communication. In this paper, we have made a
thorough investigation of synchronization of identical chaotic jerk
dynamical systems by implementing three well-known techniques: (i)
Pecora-Carroll (PC) technique, (ii) Feedback (FB) technique and (iii)
Active Passive decomposition (APD). We have given a detailed review of
these techniques followed by the results of our investigations of identical
synchronization of chaos in jerk dynamical systems. The stability of
identical synchronization in all the aforesaid methods has also been
discussed through the transversal stability analysis. Our extensive
numerical calculation results reveal that in PC and FB techniques the
x-drive configuration is able to produce the stable identical
synchronization in all the chaotic jerk dynamical systems considered by us
(except for a few cases), however y-drive and z-drive configurations do not
lead to the stable identical synchronization. For the APD approach, we have
suggested a generalized active passive decomposition, which leads to the stable
identical synchronization without being bothered about the specific form of
the jerk dynamical system. Several other active passive decompositions have
also been listed with their corresponding conditional Lyapunov exponents to
achieve the stable identical synchronization in various chaotic jerk
dynamical systems.
|
|
5
|
Second Order
Perturbation of Heisenberg Hamiltonian for Non-Oriented Ultra-Thin
Ferromagnetic Films
P. Samarasekara
Full text: Acrobat
PDF (210 KB)
|
The
second order perturbation of magnetic energy for ferromagnetic thin films
of two and three layers has been studied using classical Heisenberg
Hamiltonian. According to our model, the film with two layers is equivalent
to an oriented film, when anisotropy constants do not vary inside the film.
But the energy of films with three layers indicates periodic variation.
Introducing second order perturbation induces some sudden overshooting of
energy curves, compared with smooth energy curves obtained for oriented
ferromagnetic ultra thin films in one of our previous report. After taking
the fourth order anisotropy into account, the overshooting part dominates
by reducing the smooth part of energy graphs. Several minimums can be
observed in last 3-D graph implying that the film with N=3 can be oriented
in some preferred directions by applying a certain value of stress. The
shape of graphs of energy variation of all sc(001), fcc(001) and bcc(001)
ferromagnetic ultra thin films with second (or fourth) order anisotropy is
exactly same. Easy and hard directions of these all types with the effect
of second order anisotropy only are 34.4^{0} and 124.4^{0}, respectively.
The angle between easy and hard directions is exactly 90^{0} as expected.
Although these simulations were given for J/omega =10, D_m^{(2)}/omega =10,
K_s /omega =10 and D_m ^{(4)}/omega =5 values only, this same approach can
be carried out for any values of J/omega , D_m ^{(2)}/omega ,K_s /omega and
D_m ^{(4)}/ omega or any type of ferromagnetic material. Considering the
other terms such as dipole interaction and demagnetization factor really
complicates the simulation.
|
|
6
|
Frameable Processes
with Stochastic Dynamics
Enrico Capobianco
Full text: Acrobat
PDF (1,691 KB)
|
A
crucial goal in many experimental fields and applications is achieving
sparse signal approximations for the unknown signals or functions under
investigation. This fact allows to deal with few significant structures for
reconstructing signals from noisy measurements or recovering functions from
indirect observations. We describe and implement approximation and
smoothing procedures for volatility processes that can be represented by
frames, particularly wavelet frames, and pursue these goals by using
dictionaries of functions with adaptive degree of approximation power.
Volatility is unobservable and underlying the realizations of stochastic
processes that are non-i.i.d., covariance non-stationary, self-similar and
non-Gaussian; thus, its features result successfully detected and its
dynamics well approximated only in limited time ranges and for clusters of
bounded variability. Both jumps and switching regimes are usually observed
though, suggesting that either oversmoothing or de-volatilization may
easily occur when using standard and non-adaptive volatility models. Our
methodological proposal combines wavelet-based frame decompositions with
blind source separation techniques, and uses greedy de-noisers and feature
learners.
|
|
7
|
Ab-initio
Calculations for Forbidden M1/E2 Decay Rates in Ti XIX ion
A. Farrag
Full text: Acrobat
PDF (158 KB)
|
The
rates of the electric quadrupole E2 and magnetic dipole M1 forbidden
transitions in the ground configuration and some excited configurations of
the Ti XIX ion have been calculated. The multiconfiguration Hartree - Fock
(MCHF) method has been used. The relativistic corrections are included in
the Breit-Pauli approximation. A detailed comparison of the present
theoretical results with previous calculations and the available data in
literature is presented.
|
|
8
|
Some Properties of
Generalized Hypergeometric Thermal Coherent States
Dusan Popov
Full text: Acrobat
PDF (163 KB)
|
The
generalized hypergeometric coherent states (GHCSs) have been introduced by
Appl and Schiller [1] In the present paper we have extended some
considerations about GHCSs to the mixed (thermal) states and applied,
particularly, to the case of pseudoharmonic oscillator (PHO). The Husimi's
Q distribution function and the diagonal P - distribution function, in the
GHCSs representation, have been deduced for these mixed states. The
obtained distribution functions were used to calculate thermal averages and
to examine some nonclassical properties of the generalized hypergeometric
thermal coherent states (GHTCSs), particularly for the PHO. We have also
defined and calculated the thermal analogue of the Mandel parameter and the
thermal analogue of the second-order correlation function. By
particularizing the parameters p and q of the hypergeometric functions, we
recover the usual Barut-Girardello coherent states and their main
properties for the PHO from our previous paper [9] All calculations are
performed in terms of the Meijer's G-functions [2], which are related to
the hypergeometric functions. This manner provides an elegance and
uniformity of the obtained results and so the GHCSs become a new field of
application for these functions. Moreover, this mathematical approach can
be used also for other kind of coherent states (e.g. Klauder-Perelomov,
Gazeau-Klauder or nonlinear coherent states ([10] [12]).
|
|
9
|
Space-Filling
Curves for Quantum Control Parameters
Fariel Shafee
Full text: Acrobat
PDF (143 KB)
|
We
consider the use of space-filling curves (SFC) in scanning control
parameters for quantum chemical systems. First we show that a formally
exact SFC must be singular in the control parameters, but a finite discrete
generalization can be used with no problem. We then make general
observations about the relevance of SFCs in preference to linear scans of
the parameters. Finally we present a simple magnetic field example relevant
in NMR and show from the calculated autocorrelations that a SFC
Peano-Hilbert curve gives a smoother sequence than a linear scan.
|
|
10
|
The Spectrum of the
Lagrange Velocity Autocorrelation Function in Confined Anisotropic Liquids
Sakhnenko Elena I and Zatovsky Alexander V.
Full text: Acrobat
PDF (169 KB)
|
The
results of our further analysis of the thermal hydrodynamic fluctuations in
an anisotropic liquid under heterogeneous conditions are represented. The
heterogeneity is modeled in the form of a plane-parallel layer, the liquid
is considered is taken to be incompressible, and the rapid processes of the
angular momentum relaxation to equilibrium are ignored. The extended system
of hydrodynamics equations is linearized for small deviations from the
equilibrium values. For the case of spontaneous fluctuation fields being
present in the system of equations for the velocity and inertia tensor
components, the boundary problem solution is found in the form of an
expansion in the harmonic functions. The spectral densities of the
fluctuation correlation functions are obtained by using the fluctuation
dissipation theorem (FDT). A special attention is paid to the correlation
functions (CFs) for the velocity field in the anisotropic liquid. The
spectrum of the Lagrange velocity autocorrelation function (LVACF) and the
collective part of the self--diffusion coefficient of the molecules are
determined as functions of the coordinate normal to the confining planes.
|
|
11
|
On the Quantum Correction
of Black Hole Thermodynamics
Kourosh Nozari and S. Hamid Mehdipour
Full text: Acrobat
PDF (139 KB)
|
Bekenstein-Hawking
Black hole thermodynamics should be corrected to incorporate quantum
gravitational effects. Generalized Uncertainty Principle (GUP) provides a
perturbational framework to perform such modifications. In this paper we
consider the most general form of GUP to find black holes thermodynamics in
microcanonical ensemble. Our calculation shows that there is no logarithmic
pre-factor in perturbational expansion of entropy. This feature will solve
part of controversies in literatures regarding existence or vanishing of
this pre-factor.
|
|
12
|
A Graphic
Representation of States for Quantum Copying
Sara Felloni and Giuliano Strini
Full text: Acrobat
PDF (1,157 KB)
|
The
aim of this paper is to introduce a new graphic representation of quantum
states by means of a specific application: the analysis of two models of
quantum copying machines. The graphic representation by diagrams of states
offers a clear and detailed visualization of quantum information's flow
during the unitary evolution of not too complex systems. The diagrams of
states are exponentially more complex in respect to the standard
representation and this clearly illustrates the discrepancy of
computational power between quantum and classical systems. After a brief
introductive exposure of the general theory, we present a constructive
procedure to illustrate the new representation by means of concrete
examples. Elementary diagrams of states for single-qubit and two-qubit
systems and a simple scheme to represent entangled states are presented.
Quantum copying machines as imperfect cloners of quantum states are
introduced and the quantum copying machines of Griffiths and Niu and of
Buzek and Hillery are analyzed, determining quantum circuits of easier
interpretation. The method has indeed shown itself to be extremely
successful for the representation of the involved quantum operations and it
has allowed to point out the characteristic aspects of the quantum computations
examined.
|
Volume 3, Issue 12
(September 2006)
Full text: Acrobat
PDF (1,201 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Duality and a Renormalization Scheme for Einsteinian Gravity as a
Fix Point Within a Gravitational Gauge Framework
Eckehard W. Mielke
Full text: Acrobat
PDF (222 KB)
|
A
general scheme for a field redefinition (FR) of the coframe and the
connection is developed. Within a Yang—Mills type gauge dynamics of
gravity, configurations with double dual curvature induced by a \theta-type
Chern-Simons terms as generating function reside on an effective
Einsteinian background. The effect of the FR on the renormalization and the
relation of gravity to effective string models is studied. One encounters a
duality of weak and strong couplings of Einsteinian and renormalizable
Yang--Mills type gravity as well as an induced cosmological constant of the
Anti--de Sitter space.
|
|
2
|
High-Dimensional
Dynamics in the Delayed Hénon Map
J. C. Sprott
Full text: Acrobat
PDF (335 KB)
|
A
variant of the Hénon map is described in which the linear term is
replaced by one that involves a much earlier iterate of the map. By varying
the time delay, this map can be used to explore the transition from
low-dimensional to high-dimensional dynamics in a chaotic system with
minimal algebraic complexity, including a detailed comparison of the
Kaplan-Yorke and correlation dimensions. The high-dimensional limit
exhibits universal features that may characterize a wide range of complex
systems including the spawning of multiple coexisting attractors near the
onset of chaos.
|
|
3
|
Modified Moyal-Weyl
Star product in a Curved Non Commutative space-time
N.Mebarki,F.Khallili , M.Boussahel, and M.Haouchine
Full text: Acrobat
PDF (135 KB)
|
To
generate gravitational terms in a curved noncommutative space-time, new
Moyal-Weyl star product as well as Weyl ordering are defined. As an
example, a complex scalar mass term action is considered.
|
|
4
|
Light Scattering
Studies on the Orientational Behavior of Macromolecular Solutions in a
Shear Flow
J.A. Kupriyanova and A.V. Zatovsky
Full text: Acrobat
PDF (163 KB)
|
Theoretical
investigation of Rayleigh light scattering by a suspension of anisotropic
ellipsoidal particles subjected to a shear flow is carried out. Some
properties of the suspension of such particles caused by Brownian rotation
of these particles are studied. It is shown that the action of a shear flow
induces deformations in the shape of scattering line and results into the
non-monotonic frequency dependence of depolarized scattering spectral lines
with additional local maxima in the spectra.
|
|
5
|
Gödel’s
s Geometry: Embedding and Lanczos Spintensor
R. García-Olivo, J. López-Bonilla, S.
Vidal-Beltrán, SEPI-ESIME-Zacatenco
Full text: Acrobat
PDF (118 KB)
|
We
exhibit an open problem: To investigate if the Gödel's metric accepts
local and isometric embedding into E_6. Besides, we show that in this
metric there is a symmetric tensor which generates algebraically to Riemann
tensor and differentially to Weyl tensor.
|
|
6
|
Thermopower of The
Quantum Point Contacts Under the Effects of Boundary Roughness
Attia A. Awad Alla
Full text: Acrobat
PDF (159 KB)
|
In
this paper we, study the influence of scattering by boundary roughness on
electron transport through quantum point contact. It is found that the
thermo power of rough quantum point contact shows random and rapid
fluctuations and strong with variable the Fermi energy and electrochemical
potential. The thermoelectric efficiency as function of electrochemical
potential and the oscillations are periodic and even in the electrochemical
potential. These results agree with existing experiments and can be used as
a guideline for the evaluation of the fabrication process of quantum point
contact.
|
|
7
|
Matrix Theory and
the Modified Space-Time Uncertainty
Abbas Farmany
Full text: Acrobat
PDF (96 KB)
|
We
consider the modified space-time uncertainty in the matrix theory point of
view. First, we find a suitable theorem for the modified space-time
uncertainty. Furthermore, this theorem is proved in the matrix theory compactifications.
|
|
8
|
Analytical
One-Photon Double Differential Spectrum From In-Flight Decay of Scalar
Neutral Mesons
Giuseppe Russo and Antonio Giusa
Full text: Acrobat
PDF (253 KB)
|
We
introduce a direct simple method to evaluate the one-photon double
differential spectrum from the decay of pseudo-scalar neutral mesons. The
analytical distributions of the opening angle and of the ratio of energies
of the two gammas are then straightforwardly deduced. The physical interest
is also outlined.
|
|
9
|
On the Finite
Caputo and Finite Riesz Derivatives
A. M. A. El-Sayed and M. Gaber
Full text: Acrobat
PDF (204 KB)
|
In
this paper, we give some properties of the left and right finite Caputo derivatives.
Such derivatives lead to finite Riesz type fractional derivative, which
could be considered as the fractional power of the Laplacian operator
modelling the dynamics of many anomalous phenomena in super-diffusive
processes. Finally, the exact solutions of certain fractional diffusion
partial differential equations are obtained by using the Adomain
decomposition method and some new diffusion-wave equations are presented.
|
|
10
|
Numerical Classical
and Quantum Mechanical Simulations of Charge Density Wave Models
A. W. Beckwith
Full text: Acrobat
PDF (342 KB)
|
First,
using a driven harmonic oscillator model by a numerical scheme formulated
by Littlewood, we present a computer simulation of charge density waves
(CDW); next, we use this simulation to show how the dielectric model
presented via this procedure leads to a blow up at the initialization of a
threshold field E_T. Finding this approach highly unphysical, we initiated
inquiry into alternative models. We investigate how to present the
transport problem of CDW quantum mechanically, through a numerical
simulation of the massive Schwinger model. We find that this single-chain
quantum mechanical simulation used to formulate solutions to CDW transport
is insufficient for transport of soliton-antisolitons (S-S') through a
pinning gap model of CDW. We show that a model Hamiltonian with Peierls
condensation energy used to couple adjacent chains (or transverse wave
vectors) permits formation of S-S' that can be used to transport CDW
through a potential barrier. This addition of the Peierls condensation
energy term is essential for any quantum model of CDW to give a numerical
simulation to tunneling behavior.
|
|
11
|
A New Wave Quantum
Relativistic Equation from Quaternionic Representation of Maxwell-Dirac
Isomorphism as an Alternative to Barut-Dirac Equation
V. Christianto
Full text: Acrobat
PDF (227 KB)
|
It
is known that Barut's equation could predict lepton and hadron mass with
remarkable precision. Recently some authors have extended this equation,
resulting in Barut-Dirac equation. In the present article we argue that it
is possible to derive a new wave equation as alternative to Barut-Dirac's
equation from the known exact correspondence (isomorphism) between Dirac
equation and Maxwell electromagnetic equations via biquaternionic
representation. Furthermore, in the present note we submit the viewpoint
that it would be more conceivable if we interpret the vierbein of this
equation in terms of superfluid velocity, which in turn brings us to the
notion of topological electronic liquid. Some implications of this
proposition include quantization of celestial systems. We also argue that
it is possible to find some signatures of Bose-Einstein cosmology, which
thus far is not explored sufficiently in the literature. Further
experimental observation to verify or refute this proposition is
recommended.
|
|
12
|
A Dynamics of Charged Spherically Symmetric Thick
Shell
A. Eid
Full text: Acrobat
PDF (125 KB)
|
We
Consider a spherically symmetric thick shell in two different space times.
We have used the equation of motion for thick shell, developed by
Khakshournia and Mansouri, to obtain the equation of motion of a charged
spherical shell. We Expand the dynamical equation of motion of thick shell,
to the first order of its thickness, to compare it with the dynamics of
charged thin shell. It is shown that the effect of thickness is to speed up
the collapse of the shell.
|
Volume 3, Issue 13
(December 2006)
Full text: Acrobat
PDF (1,272 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Particle Interference without Waves
Marcello Cini
Full text: Acrobat
PDF (166 KB)
|
After
eighty years of Quantum Mechanics (QM) we have learned to live with wave
functions without worrying about their physical nature. This attitude is
certainly justified by the extraordinary success of the theory in
predicting and explaining not only all the phenomena encountered in the
domain of microphysics, but also some spectacular nonclassical macroscopic
behaviors of matter. Nevertheless one cannot ignore that the wave--particle
duality of quantum objects not only still raises conceptual problems among the
members of the small community of physicists who are still interested in
the foundations of our basic theory of matter, but also induces thousands
and thousands of physics students all around the world to ask each year, at
their first impact with Quantum Mechanics, embarrassing questions to their
teachers without receiving really convincing answers. Remember that Feynman
once said ``It is fair to say that nobody understands Quantum Mechanics''.
My purpose is to show that these difficulties can only be faced by pursuing
a line of research which takes for granted the irreducible nature of
randomness in the quantum world. This can be done by eliminating from the
beginning the unphysical concept of wave function. I believe that this
elimination is conceptually similar to the elimination of the aether,
together with its paradoxical properties, from classical electrodynamics,
accomplished by relativity theory. In our case the lesson sounds: No wave
functions, no problems about their physical nature. Furthermore, the
adoption of a statistical approach from the beginning for the description
of the physical properties of quantum systems sounds methodologically
better founded than the conventional ad hoc hybrid procedure of starting
with the determination of a system's wave function of unspecified nature
followed by a ``hand made'' construction of the probability distributions
of its .physical variables.
|
|
2
|
Metric Variation
Inside Transitioning Superconducting Shells
J. R. Claycomb and R. M. Chu
Full text: Acrobat
PDF (124 KB)
|
In
this paper, we outline the forward problem of metrical variation due to the
Casimir effect in transitioning superconducting shells. We consider a
massless scalar quantum field inside a hollow superconducting sphere and a
cylinder. Metric equations are developed describing the evolution of the
scale factors after the superconducting shells transition to the normal
state.
|
|
3
|
Black Scholes
Option Pricing with Stochastic Returns on Hedge Portfolio
J. P. Singh and S. Prabakaran
Full text: Acrobat
PDF (166 KB)
|
The
Black Scholes model of option pricing constitutes the cornerstone of
contemporary valuation theory. However, the model presupposes the existence
of several unrealistic and rigid assumptions including, in particular, the
constancy of the return on the ``hedge portfolio''. There, now, subsists
ample justification to the effect that this is not the case. Consequently,
several generalisations of the basic model have been attempted. In this
paper, we attempt one such generalisation based on the assumption that the
return process on the ``hedge portfolio'' follows a stochastic process
similar to the Vasicek model of short-term interest rates.
|
|
4
|
Co-Existence of
Regular and Chaotic Motions in the Gaussian Map
Vinod Patidar
Full text: Acrobat
PDF (193 KB)
|
In
this communication, the Gaussisn map, which has drawn less attention in the
past as compare to other one-dimensional maps, has been explored.
Particularly, the dynamical behavior of the Gaussian map and the presence
of co-existing attractors (which is a rare phenomenon in one-dimensional
maps) in the complete parameter space have been investigated. We also
suggest a possible geometrical reason for the emergence of co-existing
attractors at a particular set of system parameters, which works for all
one-dimensional maps. The regions of parameter space, where regular and
chaotic motions co-exist, have also been identified.
|
|
5
|
Does the Formation of
Temperature Dependence of Axion Walls Help Delineate a Regime Where the
Wheeler De Witt Equation Holds?
A. W. Beckwith
Full text: Acrobat
PDF (193 KB)
|
We
examine from first principles the implications of the 5^{th} Randall
Sundrum Brane world dimension in terms of setting initial conditions for
chaotic inflationary physics. Our model pre supposes that the inflationary
potential pioneered by Guth is equivalent in magnitude in its initial
inflationary state to the effective potential presented in the Randall
-Sundrum model We also consider an axion contribution to chaotic inflation
(which may have a temperature dependence) which partly fades out up to the
point of chaotic inflation being matched to a Randall -- Sundrum effective
potential. If we reject an explicit axion mass drop off to infinitesimal
values at high temperatures, we may use the Bogomolnyi inequality to re
scale and re set initial conditions for the chaotic inflationary potential.
Then the Randall-Sundrum brane world effective potential delineates the end
of the dominant role of di quarks, and the beginning of inflation. It also
leads to a new region where the Wheeler De Witt equation
holds.
|
|
6
|
Extended Non
Symmetric Gravitation Theory with a Scalar Field in Non Commutative
Geometry
N.Mebarki, F.Khelili and J.Mimouni
Full text: Acrobat
PDF (186 KB)
|
An
extended method to reformulate the non symmetric gravitation theory in the
non commutative geometry formalism is presented where all the lagrangian
terms, including the various interaction ones with scalar fields, emerge
naturally.
|
|
7
|
Some Important
Features of Ultra-Light Particles, Induced Cosmological Constant and
Massive Gravitons in Modern Cosmology Theories
El-Nabulsi Ahmad-Rami
Full text: Acrobat
PDF (267 KB)
|
Some
important features of ultra-light masses and induced cosmological constant
implemented in Einstein gravity theory from supergravities arguments and
non-minimal coupling effects are presented and discussed in some details in
modern cosmology where massive gravitons are taken into account.
|
|
8
|
Building of Heat Kernel on Non-CompactHomogeneous Spaces
V. Mikheyev and I.
Shirokov
Full text: Acrobat
PDF (250 KB)
|
Method
of the solution of the main problem of homogeneous spaces thermodynamics on
non-compact spaces in the case of non-compact homogeneous spaces is
presented in the article. The method is based on the formalism of coadjoint
orbits. In that article we present algorithm that allows efficiently
evaluate heat kernel on non-compact homogeneous spaces. The method is
illustrated with non-trivial example.
|
|
9
|
Radiating Shell
Supported by a Phantom Energy
A. Eid
Full text: Acrobat
PDF (136 KB)
|
I
describe the evolution of a thin spherically symmetric self-gravitating
phantom shell around the radiating shell. The general equations describing
the motion of shell with a general form of equation of state are derived.
The stability analysis of this phantom shell to linearized spherically
symmetric perturbation about static equilibrium solution is carried out.
|
|
10
|
Radial Matrix
Elements for the Hydrogen Atom
M. Enciso-Aguilar, J. López-Bonilla and M.
S'anchez-Meraz
Full text: Acrobat
PDF (123 KB)
|
It
is known that the hydrogenlike atom can be studied as a Morse oscillator,
then here we show that these fact leads to an interesting method to obtain the
matrix elements for the Coulomb potential.
|
|
11
|
A Simply
Regularized Derivation of the Casimir Force
H. Razmi
Full text: Acrobat
PDF (136 KB)
|
We
want to calculate the Casimir force between two parallel, uncharged,
perfectly conducting plates by a simple automatically regularized approach.
Although in the well-known methods one should explicitly subtract the
energy term due to the empty space to regularize the calculation, here, the
regularization is simply/implicitly achieved by considering only the energy
per unit area of each plate.
|
Volume 4, Issue 14 (March
2007)
Full text: Acrobat
PDF (1,192 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
On the Dynamics of a n-D Piecewise Linear Map
Zeraoulia Elhadj
Full text: Acrobat
PDF (130 KB)
|
This
paper, derives sufficient conditions for the existence of chaotic
attractors in a general n-D piecewise linear discrete map, along the exact
determination of its dynamics using the standard definition of the largest
Lyapunov exponent.
|
|
2
|
Flow of Unsteady Dusty Fluid Under Varying
Pulsatile Pressure Gradient in Anholonomic Co-ordinate System
B.J.Gireesha, C.S.Bagewadi and B.C.Prasanna
Kumara
Full text: Acrobat
PDF (174 KB)
|
An
analytical study of unsteady viscous dusty fluid flow with uniform distribution
of dust particles between two infinite parallel plates has been studied by
taking into the account of the influence of pulsatile pressure gradient.
The flow analysis is carried out using differential geometry techniques and
analytical solutions of the problem is obtained with the help of Laplace
Transform technique and which are discussed with the help of graphs.
|
|
3
|
Exact Solutions for Nonlinear
Evolution Equations Via Extended Projective Riccati Equation Expansion
Method
M A Abdou
Full text: Acrobat
PDF (152 KB)
|
By
means of a simple transformation, we have shown that the
generalized-Zakharov equations, the coupled nonlinear Klein-Gordon-Zakarov
equations, the GDS, DS and GZ equations and generalized Hirota-Satsuma
coupled KdV system can be reduced to the elliptic-like equations. Then, the
extended projective Riccati equation expansion method is used to obtain a
series of solutions including new solitary wave solutions,periodic and
rational solutions. The method is straightforward and concise, and its
applications is promising.
|
|
4
|
Evolutionary Neural Gas (ENG)
: A Model of Self Organizing Network from Input Categorization
I. Licata and L. Lella
Full text: Acrobat
PDF (385 KB)
|
Despite
their claimed biological plausibility, most self organizing networks have strict
topological constraints and consequently they cannot take into account a
wide range of external stimuli. Furthermore their evolution is conditioned
by deterministic laws which often are not correlated with the structural
parameters and the global status of the network, as it should happen in a
real biological system. In nature the environmental inputs are noise
affected and ``fuzzy''. Which thing sets the problem to investigate the
possibility of emergent behaviour in a not strictly constrained net and
subjected to different inputs. It is here presented a new model of
Evolutionary Neural Gas (ENG) with any topological constraints, trained by
probabilistic laws depending on the local distortion errors and the network
dimension. The network is considered as a population of nodes that coexist
in an ecosystem sharing local and global resources. Those particular
features allow the network to quickly adapt to the environment, according
to its dimensions. The ENG model analysis shows that the net evolves as a
scale-free graph, and justifies in a deeply physical sense- the term
``gas'' here used.
|
|
5
|
Discrete Groups Approach to Non Symmetric
Gravitation Theory
N.Mebarki, F.Khelili and J.Mimouni
Full text: Acrobat
PDF (157 KB)
|
A
generalized discrete group formalism is obtained and used to describe the
Non Symmetric Gravity theory (NGT) coupled to a scalar field. We are able
to derive explicitly the various terms of the NGT action including the
interaction term without any ad-hoc assumptions.
|
|
6
|
Quantization of the Scalar
Field Coupled Minimally to the Vector Potential
W. I. Eshraim and N. I. Farahat
Full text: Acrobat
PDF (130 KB)
|
A
system of the scalar field coupled minimally to the vector potential is
quantized by using canonical path integral formulation based on Hamilton-Jacobi
treatment. The equation of motions are obtained as total differential
equation and the integrability conditions are examined.
|
|
7
|
A Generalized Option Pricing
Model
J. P. Singh
Full text: Acrobat
PDF (197 KB)
|
The
Black Scholes model of option pricing constitutes the cornerstone of
contemporary valuation theory. However, the model presupposes the existence
of several unrealistic assumptions including the lognormal distribution of
stock market price processes. There, now, subsists abundant empirical
evidence that this is not the case. Consequently, several generalisations
of the basic model have been attempted with relaxation of some of the
underlying assumptions. In this paper, we postulate a generalization that
contemplates a statistical feedback process for the stochastic term in the
Black Scholes partial differential equation. Several interesting
implications of this modification emanate from the analysis and are
explored.
|
|
8
|
Derivation of the Radiative
Transfer Equation Inside a Moving Semi-Transparent Medium of Non Unit
Refractive Index
V. LE DEZ and H. SADAT
Full text: Acrobat
PDF (297 KB)
|
The
derivation of the radiative transfer equation inside a moving
semi-transparent medium of non unit constant refractive index has been
completely achieved, leading to an exactly similar equation as in the case
of a unit index, unless it is expressed in a particular frame with
particular time and space co-ordinates; defining first the ``equivalent
vacuum'' and the ``matter'' space associated to its ``matter'' co-ordinates
with the help of the Gordon's metric, it is shown that an observer at rest
in vacuum perceives the isotropic moving medium as an anisotropic uniaxial
medium of given optical axis, for which it is possible to derive general
transmission and reflection rules for electromagnetic fields; however the
exhibited refractive index characterising the moving medium, relatively to
the observer located in vacuum, is not an effective index but only an
apparent one without any energetic significance, and the specific intensity
must be obtained relatively to a given observer at rest located inside the
moving medium; finally the general form of the radiative transfer equation
is obtained in the moving medium.
|
|
9
|
Quantum Images and the Measurement
Process
Fariel Shafee
Full text: Acrobat
PDF (124 KB)
|
We
argue that symmetrization of an incoming microstate with similar states in
a sea of microstates contained in a macroscopic detector can produce an
effective image, which does not contradict the no-cloning theorem, and such
a combinatorial set, with conjugate quantum numbers can form virtual bound
states with the incoming microstate. This can then be used with first
passage random walk interactions to give the right quantum mechanical
weight for different measured eigenvalues.
|
Volume 4, Issue 15 (July
2007)
Full text: Acrobat
PDF (1,725 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Mental and Physical Objects
in Quantum Mechanics:Any Lessons for Other Disciplines?
M. Cini
Full text: Acrobat
PDF (126 KB)
|
The
standard formulation of Quantum Mechanics has raised from its beginning
animated discussions about the interpretation of the counterintuitive
properties of mental objects (wave functions or Schrödinger waves)
introduced to represent the properties of the physical objects. Two
questions have since then been formulated to which a universally accepted
answer is still lacking. The first one (Bohr, von Neumann) concerns the
ontological nature of physical reality (the existence of classical objects)
and the role of the observer (wave packet collapse) in assessing it. The
second one is the non local character of quantum physical quantities
(Einstein Podolski Rosen [EPR] long distance correlation of particles). An
alternative formulation of Quantum Mechanics, originally proposed in 1932
by Eugene Wigner, taken up by Richard Feynman in 1987, and reelaborated by
myself in the years from 1998 to 2003, is possible. The mental objects of
standard Quantum Mechanics (Schrödinger waves) no longer appear in
this new formulation and are replaced by new ones (Wigner functions) which
do not show any more the puzzling properties which worried Einstein. My
conclusion from the preceding discussion is that different explanations of
a given set of experimental data may be derived according to the different
nature of the mental objects introduced to represent the properties of the
physical objects involved. The confusion between these two kind of objects
may be, however, very misleading. I will finally discuss two examples of
this conclusion from Biology and Economics.
|
|
2
|
Fantappié-Arcidiacono
Theory of Relativity Versus Recent Cosmological Evidences : A Preliminary
Comparison
L. Chiatti
Full text: Acrobat
PDF (183 KB)
|
Notwithstanding
the Fantappié -Arcidiacono theory of projective relativity was
introduced more than half a century ago, its observational confirmations in
cosmology (the only research field where its predictions differ from those
of the Einsteinian relativity) are still missing. In line of principle,
this theory may be proposed as a valid alternative to the current views
assuming the dominance of dark matter and inflationary scenarios. In this
work, the relativistic transformation of the Poynting vector associated
with the reception of electromagnetic waves emitted by astronomical objects
is derived in the context of the special version of the theory. On the
basis of this result, and some heuristic assumptions, two recent
collections of observational data are analyzed : the m-z relation for type
Ia supernovae (SNLS, SCP collaborations) and the log N -- log S relation
obtained from the FIRST survey of radio sources at 1.4 GHz. From the first
analysis, values are derived for the current density of matter in the
universe and the cosmological constant that are of the same order of
magnitude as those obtained from the most recent conventional evaluations.
The second analysis results in an evolutionary trend of number of sources
as a function of z that is in qualitative agreement with that obtained from
more conventional analyses. Therefore it can be concluded, as a preliminary
result, that the application of the theory to the study of cosmological
processes leads to results which not substantially differ from these
currently accepted. However, in order to obtain a more reliable comparison
with observations, a solution is needed for the gravitational equations in
the general version of the theory.
|
|
3
|
Considering Relativistic
Symmetry as the First Principle of Quantum Mechanics
T. Kawahara
Full text: Acrobat
PDF (143 KB)
|
On
the basis of the relativistic symmetry of Minkowski space, we derive a
Lorentz invariant equation for a spread electron. This equation slightly
differs from the Dirac equation and includes additional terms originating
from the spread of an electron. Further, we calculate the anomalous
magnetic moment based on these terms. These calculations do not include any
divergence; therefore, renormalization procedures are unnecessary. In
addition, the relativistic symmetry existing among coordinate systems will
provide a new prospect for the foundations of quantum mechanics like the
measurement process.
|
|
4
|
On Certain Quantization
Aspects of (Generalized) Toda Systems
M. Legare
Full text: Acrobat
PDF (141 KB)
|
Ordinary
and gl(n,\R) generalized Toda systems as well as a related hierarchy are
probed with respect to certain quantization characteristics.
``Quantum" canonical and Poisson transformations are used to study
quantizations of transformed Toda systems. With a Lax pair setting, a
hierarchy of related systems are shown and their quantizations discussed.
Finally, comments are added about quantum aspects of gl(n,\R) generalized
Toda systems with the approaches of deformation quantization or quantum
groups in mind.
|
|
5
|
Klein -Gordon Equation for
the Heating of the Fermionic Gases
M.Pelc, J. Marciak - Kozlowska and
M. Kozlowski
Full text: Acrobat
PDF (77 KB)
|
In
this paper the model for the interaction of the ultra-short laser pulses
with matter is proposed. The Klein-Gordon equation for heat transport is
developed and solved. The condition for the existence of the massless heat
carriers is formulated. The condition is V\tau =\hbar /8, where V is
potential energy, \tau is the relaxation time. The new thermal Klein-Gordon
equation can be applied to the study of thermal processes for the fermionic
gases (electron, nucleon).
|
|
6
|
Deformation Quantization of
Submanifolds and Reductions via Duflo-Kirillov-Kontsevich Map
A. Chervov and L. Rybnikov
Full text: Acrobat
PDF (185 KB)
|
We
propose the following recipe to obtain the quantization of the Poisson
submanifold $N$ defined by the equations f_i=0 (where f_i are Casimirs)
from the known quantization of the manifold M: one should consider factor
algebra of the quantized functions on M by the images of D(f_i), where D:
Fun(M) \to Fun(M)\otimes \CC[\hbar] is Duflo-Kirillov-Kontsevich map. We
conjecture that this algebra is isomorphic to quantization of Fun(N) with
Poisson structure inherited from M. Analogous conjecture concerning the Hamiltonian
reduction saying that "deformation quantization commutes with
reduction" is presented. The conjectures are checked in the case of
S^2 which can be quantized as a submanifold, as a reduction and using
recently found explicit star product. It's shown that all the constructions
coincide.
|
|
7
|
Hidden Symmetry, Excitonic
Transitions and Two-Dimensional Kane's Exciton in the Quantum Well
E.M. Kazaryan, L.S. Petrosyan, and
H.A. Sarkisyan
Full text: Acrobat
PDF (131 KB)
|
The
influence of hidden symmetry on two-dimensional excitonic states in
semiconductor quantum wells is investigated. It is shown that excitonic
states in quantum wells, with the parabolic dispersion law for the electron
and hole, and Sommerfeld's coefficients for excitonic transitions are
determined only with the principle quantum number within the framework of
two-dimensional Coulomb potential. This is a result of hidden symmetry of two-dimensional
Coulomb problem, conditioned by the existence of two-dimensional analog of
the Runge-Lentz vector. For the narrow gap semiconductor quantum well with
the non-parabolic dispersion law of electron and hole, in the two-band Kane
model, it is shown that two-dimensional excitonic states are described in
the frames of analog of the Klein-Gordon equation with the two-dimensional
Coulomb potential. Non-stability of the ground state of the two-dimensional
Kane's exciton investigated.
|
|
8
|
Debever-Penrose Principal
Directions in Terms of Null Canonical Vectors
N. Hamdan, R. Garcia-Olivo, and J.
Lopez-Bonilla
Full text: Acrobat
PDF (65 KB)
|
We
show explicit expressions to construct the Debever-Penrose vectors from a
given null canonical tetrad.
|
|
9
|
How Can Brane World Physics
Influence Axion Temperature Dependence, Initial Vacuum
States, and
Permissible Solutions to the Wheeler-De Witt Equation in Early Universe
Cosmology?
A.W. Beckwith
Full text: Acrobat
PDF (305 KB)
|
We
use an explicit Randall-Sundrum brane world effective potential as
congruent with conditions needed to form a minimum entropy starting point
for an early universe vacuum state. We are investigating if the Jeans
instability criteria mandating low entropy, low temperature initial pre
inflation state configuration can be reconciled with thermal conditions of
temperatures at or above ten to the 12 Kelvin, or higher, when cosmic
inflation physics takes over. We justify this by pointing to the Ashtekar,
Pawlowski, and Singh (2006) article about a prior universe being modeled
via their quantum bounce hypothesis which states that this prior universe
geometrically can be modeled via a discretized Wheeler -- De Witt equation
, with it being the collapsing into a quantum bounce point singularity
converse of the present day universe expanding from the quantum bounce
point so delineated in their calculations. The prior universe would provide
thermal excitation into the Jeans instability mandated cooled down initial
state, with low entropy, leading to extreme graviton production. This
necessitates reconciling the lack of a quantum bounce seen in brane world
models with the proof of relic graviton production so provided in the
simulation so provided. This is also a way of getting around the get around
the fact that conventional cosmological CMB is limited by a barrier as of a
red shift limit of about z = 1000, i.e. when the universe was about 1000
times smaller and 100,000 times younger than today as to photons, and to
come up with a working model of quintessence scalar fields which permits
relic generation of dark matter/dark energy.
|
|
10
|
Gravitation and Gauge Fields
in a Space with 4+n Dimensions
Ion Rosu
Full text: Acrobat
PDF (155 KB)
|
In
this paper, for a particular symmetry, we obtain the geodesics' and field
equations in a space with 4+n dimensions. The geodesics equations represent
the motion equations in the presence of gravitation field and gauge fields.
All fields depend of x=\left\{ {x^\alpha } \right\}\in M^4 and do not
depend of y=\left\{ {y^k} \right\}\in M^n. The field equations are Einstein
equations in a space with 4+n dimensions. The gravitation field is
represented by the tensor components G_{\alpha \beta } which satisfy
nonlinear equations in M^4. If M^4 is a subspace in a space with 4+n_g
dimensions, then G_{\alpha \beta } =G_{\alpha \beta }^0 +g_\alpha ^{r_0 }
g_{\beta r_0 } and in this space the fields g_\alpha ^{r_0 } satisfy the
same type of equations satisfied by the gauge fields g_\alpha ^{r } . This
allows the quantification of gravitation fields $g_\alpha ^{r_0 }.
|
|
11
|
Fractional Path Integral and
Exotic Vacuum for the Free Spinor Field Theory with Grassman Anticommuting
Variables
EL-NABULSI Ahmad Rami
Full text: Acrobat
PDF (119 KB)
|
A
systematic formulation of fractional path integral for the free spinor
field theory is presented and discussed within the framework of fractional
action-like variational approach (or fractionally differentiated Lagrangian
function) recently formulated by the author. Some interesting explicit
formulas and features are discussed in some details.
|
|
12
|
Randomized Time and Frequency
Domain Estimation from Semimartingales
Enrico Capobianco
Full text: Acrobat
PDF (580 KB)
|
One
established fact in financial economics and mathematics is the convergence
of realised to integrated volatility according to the quadratic variation
principle. When computed in general semimartingale asset price models, the
cumulative squared high frequency returns represent consistent estimators
of the integrated volatility. Both time and frequency domain estimators are
available for solving what, in an unifying approach, could be considered an
inverse problem, the recovery of latent volatility from the realizations of
observable return processes. Since the relation between realised and
integrated volatility implies that one is transformed into the other with
noise, we work in a simulated environment of Brownian motion paths for
exemplifying the semimartingale context and produce randomized estimators
for the volatility. With the support of experimental evidence, we can show
the consistency of time- and frequency-based volatility estimators and
their speed of convergence to the quadratic variation limit.
|
|
12
|
Microwave Induced Tunneling
in Stub Tuner Mesoscopic Device and its Chaotic Behavior
Attia A. AwadAlla, Arafa H. Aly,
and Adel H. Phillips
Full text: Acrobat
PDF (104 KB)
|
We
study the thermoelectric transport properties of mesoscopic devices in
which the dynamics of the electrons are chaotic. The present studied device
is an electronic stub tuner modeled as S-Sm-S-Sm-S (S-superconductor,
Sm-semiconductor). The thermo power of the present device is expressed in
terms of the conductance of the system, which is derived by the technique
based on Landauer-Buttiker equation. The influence of time-varying fields
on the transport through such device has been taken into consideration and
also the effect of magnetic field. The results show an oscillatory behavior
of the dependence of the thermo power on both the magnetic field and
frequency of the induced field. These oscillations appear as random
fluctuation in peak heights. Analysis of these results shows that
mesoscopic fluctuations obey Lorentzian distribution and under some
conditions it is an exponential distribution. Our results are found
concordant with those in the literature.
|
|
|
Classical Heisenberg
Hamiltonian Solution of Oriented Spinel Ferrimagnetic Thin Films
P. Samarasekara
Full text: Acrobat
PDF (147 KB)
|
The
classical Heisenberg Hamiltonian was solved for oriented spinel thin and
thick cubic ferrites. The dipole matrix of complicated cubic cell could be
simplified into the form of dipole Matrix of simple cubic cells. This study
was confined only to the highly oriented thin films of ferrite. The
variation of total energy of Nickel ferrite thin films with angle and
number of layers was investigated. Also the change of energy with stress
induced anisotropy for Nickel ferrite films with N=5 and 1000 has been
studied. Films with the magnetic moments ratio 1.86 can be easily oriented
in \theta =90^{0} direction when Nis
greater than 400. Although this simulation was performed only for
\frac{J}{\omega }=100,\frac{\sum\limits_{m=1}^N D_m ^{(\ref{eq2})}}{\omega
}=10,\frac{H_{in} }{\omega }=\frac{H_{out} }{\omega }=0,\frac{K_s }{\omega
}=5 \mbox{ and } \frac{\sum\limits_{m=1}^N D_m ^{(4)}}{\omega }=5 as an
example, these equations can be applied for any value of \frac{J}{\omega
},\frac{\sum\limits_{m=1}^N D_m ^{(\ref{eq2})}}{\omega },\frac{H_{in}
}{\omega },\frac{H_{out} }{\omega },\frac{K_s }{\omega } \, \mbox{ and } \,
\frac{\sum\limits_{m=1}^N D_m
^{(4)}}{\omega
}.
|
Volume 4, Issue 16II (
December 2007)
Full text: Acrobat
PDF (2,452 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
The Limits of Atomism, the Bohm Way of a
New Ontology
Ryo Morikawa
Full text: Acrobat
PDF (107 KB)
|
In
this paper, we survey a developed outline of atomism. The paper clarifies
that this leading principle of modern physics faces a limitation. This
limitation is a limit of ontology. We are unable to recognize a concrete
ontology; we have only epistemology. Therefore, we discuss this issue from
a philosophical viewpoint by referring to Cassirer's philosophy. These
arguments will clarify that there is a need for a new ontology that will be
able to make a consistent understanding from the microscopic to the macroscopic
level. To do this we argue the case of the new ontology that was introduced
by Bohm. Also, we will see the mathematical formalism of cyclic ontology as
a new ontology for the process. Then we will see that this formalism is
able to obtain the Heisenberg equation as well as the Bohm equation.
|
|
2
|
Physics of Life from First
Principles
Michail Zak
Full text: Acrobat
PDF (562 KB)
|
The
objective of this work is to extend the First Principles of Newtonian
mechanics to include modeling of behavior of Livings. One of the most
fundamental problems associated with modeling life is to understand a
mechanism of progressive evolution of complexity typical for living
systems. It has been recently recognized that the evolution of living
systems is progressive in a sense that it is directed to the highest levels
of complexity if the complexity is measured by an irreducible number of
different parts that interact in a well-regulated fashion. Such a property
is not consistent with the behavior of isolated Newtonian systems that
cannot increase their complexity without external forces. Indeed, the
solutions to the models based upon dissipative Newtonian dynamics
eventually approach attractors where the evolution stops, while these
attractors dwell on the subspaces of lower dimensionality, and therefore,
of the lower complexity. If thermal forces are added to mechanical ones,
the Newtonian dynamics is extended to the Langevin dynamics combining both
mechanics and thermodynamics effects; it is represented by stochastic
differential equations that can be utilized for more advanced models in
which randomness stands for multi-choice patterns of behavior typical for
living systems. However, even those models do not capture the main property
of living systems, i.e. their ability to evolve towards increase of
complexity without external forces. Indeed, the Langevin dynamics is
complemented by the corresponding diffusion equation that describes the
evolution of the distribution of the probability density over the state
variables; in case of an isolated system, the entropy of the probability
density cannot decrease, and that expresses the second law of thermodynamics.
From the viewpoint of complexity, this means that the state variables of
the underlying system eventually start behaving in a uniform fashion with
lesser distinguished features, i.e. with lower complexity. Reconciliation
of evolution of life with the second law of thermodynamics is the central
problem addressed in this paper. It is solved via introduction of the First
Principle for modeling behavior of living systems. The structure of the
model is quantum-inspired: it acquires the topology of the Madelung
equation in which the quantum potential is replaced with the information
potential. As a result, the model captures the most fundamental property of
life: the progressive evolution, i.e. the ability to evolve from disorder
to order without any external interference. The mathematical structure of
the model can be obtained from the Newtonian equations of motion
(representing the motor dynamics) coupled with the corresponding Liouville
equation (representing the mental dynamics) via information forces. The unlimited
capacity for increase of complexity is provided by interaction of the
system with its mental images via chains of reflections: What do you think
I think you think?. All these specific non-Newtonian properties equip the
model with the levels of complexity that match the complexity of life, and
that makes the model applicable for description of behaviors of ecological,
social and economics systems.
|
|
3
|
Theoretical Physics of DNA:
New Ideas and Tendencies in the Modeling of the DNA Nonlinear Dynamics
Yakushevich L.V.
Full text: Acrobat
PDF (254 KB)
|
Theoretical
studies of the DNA nonlinear dynamics successfully started with the model
of Englander [1] in 1980, was intensively developed at the end of the 20th
century. Most of the proposed models and results obtained have been
summarized in the reviews [2-5] and books [6-9]. And what was happened
after that? What new ideas, results and tendencies one can observe in this
field of science now? Here we describe some of them.
|
|
4
|
Mathematical and Data Mining
Contributions to Dynamics and Optimization of Gene-Environment Networks
Gerhard-Wilhelm Weber, Pakize
Taylan , Başak Akteke-Őztürka, and Őmür Uğur
Full text: Acrobat
PDF (255 KB)
|
This
paper further introduces continuous optimization into the fields of
computational biology and environmental protection which belong to the most
challenging and emerging areas of science. It refines earlier ones of our
models on gene-environment patterns by the use of optimization theory. We
emphasize that it bases on and presents work done in ougur, weber-et-al..
Furthermore, our paper tries to detect and overcome some structural
frontiers of our methods applied to the recently introduced {\it
gene-environment networks}. Based on the experimental data, we investigate
the ordinary differential equations having nonlinearities on the right-hand
side and a generalized treatment of the absolute shift term which
represents the environmental effects. The genetic process is studied by a
time-discretization, in particular, Runge-Kutta type discretization. The
possibility of detecting stability and instability regions is being shown
by a utilization of the combinatorial algorithm of Brayton and Tong which
is based on the orbits of polyhedra. The time-continuous and discrete
systems can be represented by means of matrices allowing biological
implications, they encode and are motivated by our gene-environment
networks. A specific contribution of this paper consists in a careful but
rigorous integration of the environment into modeling and dynamics, and in
further new sights. Relations to parameter estimation within modeling,
especially, by using optimization, are indicated, and future research is
addressed, especially towards the use of stochastic differential equations.
This practically motivated and theoretically elaborated work is devoted for
a contribution to better health care, progress in medicine, a better
education and more healthy living conditions recommended.
|
|
5
|
Folding Proteins:(How to Set
up an Effcient Metrics for Dealing with Complex Systems)
Alessandro Giuliani
Full text: Acrobat
PDF (173 KB)
|
Protein
folding, the process allowing a monodimensional string of aminoacids to
acquire its characteristic shape in solution, is where complexity starts,
as clearly stated in a famous paper entitled `Proteins: where physics of
simplicity and complexity meet' by Hans Frauenfelder and Peter Wolynes [1].
The starting of complexity implies the coupling of a thorough and accurate
knowledge of the `first principles' and potentials (hydrophobic
interactions, hydrogen bonding, size constraints etc.) acting at the
microscopic level with the substantially empirical (and very inaccurate)
predictions on the actual structure of proteins when in solution. Along the
pilgrimage to the `translation key' from protein sequence to structure,
scientists of different cultures have met and exchanged ideas and, as often
happens to pilgrims, even the nature of the goal changed along the way.
This is a tale from a section of this path (still very far to be completed)
in which some peculiarities of the network based formalization of protein
sequence and structure are presented as an example of a possible way to
generate an efficient metrics to study phenomena in which many different
actors interact in a complex way.
|
|
6
|
Evolution of Norms in a
Multi-Level Selection Model of Conflict and Cooperation
J. M. Pacheco, F. C. Santos and F.
A. C. C. Chalub
Full text: Acrobat
PDF (356 KB)
|
We
investigate the evolution of social norms in a game theoretical model of
multi-level selection and mutation. Cooperation is modeled at the lower
level of selection by means of a social dilemma in the context of indirect
reciprocity, whereas at the higher level of selection conflict is
introduced via different mechanisms. The model allows the emergence of
norms requiring high levels of cognition. Results show that natural
selection and mutation lead to the emergence of a robust yet simple social
norm, which we call stern-judging. Stern-judging is compatible with
expectations that anthropologists have regarding the Pleistocene hunter gatherer
communities. Perhaps surprisingly, it also fits very well recent studies of
the behavior of reputation-based e-trading. Under stern-judging, helping a
good individual or refusing help to a bad individual leads to a good
reputation, whereas refusing help to a good individual or helping a bad one
leads to a bad reputation. The lack of ambiguity of stern-judging, where
implacable punishment is compensated by prompt forgiving, supports the idea
that simplicity is often associated with evolutionary success.
|
|
7
|
Multiboundary Algebra as
Pregeometry
Ben Goertzel
Full text: Acrobat
PDF (96 KB)
|
It
is well known that the Clifford Algebras, and their quaternionic and
octonionic subalgebras, are structures of fundamental importance in modern
physics. ~Geoffrey Dixon has even used them as the centerpiece of a novel
approach to Grand Unification. ~ In the spirit of Wheeler's notion of
"pregeometry" and more recent work on quantum set theory, the
goal of the present investigation is to explore how these algebras may be
seen to emerge from a simpler and more primitive order. In order to observe
this emergence in the most natural way, a pregeometric domain is proposed
that consists of two different kinds of boundaries, each imposing different
properties on the combinatory operations occurring between elements they
contain. ~It is shown that a very simple variant of this kind of
"multiboundary algebra" gives rise to Clifford Algebra, in much
the same way as Spencer-Brown's simpler single-boundary algebra gives rise
to Boolean algebra.
|
|
8
|
Scale Relativity: A Fractal
Matrix for Organization in Nature
Laurent Nottale
Full text: Acrobat
PDF (570 KB)
|
In
this review paper, we recall the successive steps that we have followed in
the construction of the theory of scale relativity. The aim of this theory
is to derive the physical behavior of a nondifferentiable and fractal
space-time and of its geodesics (to which wave-particles are identified),
under the constraint of the principle of relativity of all scales in
nature. The first step of this construction consists in deriving the
fundamental laws of scale dependence (that describe the internal structures
of the fractal geodesics) in terms of solutions of differential equations
acting in the scale space. Various levels of these scale laws are
considered, from the simplest scale invariant laws to the log-Lorentzian
laws of special scale relativity. The second step consists in studying the
effects of these internal fractal structures on the laws of motion. We find
that their main consequence is the transformation of classical mechanics in
a quantum-type mechanics. The basic quantum tools (complex, spinor and
bi-spinor wave functions) naturally emerge in this approach as consequences
of the nondifferentiability. Then the equations satisfied by these wave
functions (which may themselves be fractal and nondifferentiable), namely,
the Schrödinger, Klein-Gordon, Pauli and Dirac equations, are
successively derived as integrals of the geodesics equations of a fractal space-time.
Moreover, the Born and von Neumann postulates can be established in this
framework. The third step consists in addressing the general scale
relativity problem, namely, the emergence of fields as manifestations of
the fractal geometry (which generalizes Einstein's identification of the
gravitational field with the manifestations of the curved geometry). We
recall that gauge transformations can be identified with transformations of
the internal scale variables in a fractal space-time, allowing a geometric
definition of the charges as conservative quantities issued from the
symmetries of the underlying scale space, and a geometric construction of
Abelian and non-Abelian gauge fields. All these steps are briefly
illustrated by examples of application of the theory to various sciences,
including the validation of some of its predictions, in particular in the
domains of high energy physics, sciences of life and astrophysics.
|
|
9
|
Fractal Time, Observer
Perspectives and Levels of Description in Nature
Susie Vrobel
Full text: Acrobat
PDF (327 KB)
|
This
paper reviews various approaches to modeling reality by differentiating notions
of time which underly those models. Basic notions of time presupposed in
physical theories are briefly described and analyzed in terms of the levels
of description taken into account, the interfacial cut assumed between the
observer and the rest of the world, the resulting observer perspectives and
the extent to which these notions are based on temporal natural
constraints. Notions of time in physical theories are secondary constructs,
derived from our primary experiences of time. Therefore, we must regard our
theories as anthropocentric -- derived from abstractions and metaphors
resulting from our embodied cognition. Theories based on the notion of
fractal time and fractal space-time are generalizations or alternative
descriptions which allow for a more differentiated modelling of reality.
The resulting temporal observer perspectives allow for further
differentiation. The notion of fractal time logically precedes those of
fractal space-time, as it is based on the primary experiences of time:
succession, simultaneity, duration and an extended Now. Against this
background, the internal differentiation of the observer and his degree of
both conscious and unconscious contextualization turn out to be vital
ingredients in our reality generation game. I am fully aware of the fact
that the selection of concepts presented here is neither complete nor
unbiased and is coloured by my own temporal observer perspective.
|
Volume 5, Issue 17 (March
2008)
Full text: Acrobat
PDF (3,010 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
A Review of Leading Quantum
Gravitational Corrections to Newtonian Gravity
Arif Akhundov and Anwar Shiekh
Full text: Acrobat
PDF (649 KB)
|
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.
|
|
2
|
Radiation
Reaction at Extreme Intensity
Richard T. Hammond
Full text: Acrobat
PDF (165 KB)
|
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.
|
|
3
|
Super-Light Electromagnetic
Wave With Longitudinal And Transversal Modes
M.M. Kononenko
Full text: Acrobat
PDF (177 KB)
|
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.
|
|
4
|
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)
|
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.
|
|
5
|
Hamilton-Jacobi Formulation
of a Non-Abelian Yang-Mills Theories
W. I. Eshraim and N. I. Farahat
Full text: Acrobat
PDF (126 KB)
|
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
|
|
6
|
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)
|
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.
|
|
7
|
Penrose Model Potential,
Compared With Coleman- Weinberg Potential for Early Universe Scalar
Evolution
A.W. Beckwith
Full text: Acrobat
PDF (174 KB)
|
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.
|
|
8
|
Increasing Effective
Gravitational Constant In Fractional Add Brane Cosmology
El-Nabulsi Ahmad Rami
Full text: Acrobat
PDF (136 KB)
|
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'.
|
|
9
|
A Two-Dimensional Discrete
Mapping with C^{Infinity} Multifold Chaotic Attractors
Zeraoulia Elhadj and J. C. Sprott
Full text: Acrobat
PDF (638 KB)
|
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.
|
|
10
|
Bosons-Parafermions
Wess-Zumino Model
L. Maghlaoui and N. Belaloui
Full text: Acrobat
PDF (159 KB)
|
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.
|
|
11
|
Geometrodynamics of
Information on Curved Statistical Manifolds and Its Applications to Chaos
C. Cafaro and S. A. Ali
Full text: Acrobat
PDF (256 KB)
|
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.
|
|
12
|
Stochastic Measures and Modular
Evolution in Non-Equilibrium Thermodynamics
Enrique Hernandez-Lemus, and Jesus
K. Estrada-Gil
Full text: Acrobat
PDF (239 KB)
|
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.
|
|
13
|
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)
|
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.
|
|
14
|
Exact Solution of The Non -
Central Modified Kratzer Potential Plus a Ring - Shaped Like Potential By
The Factorization Method
J. Sadeghi and B. Pourhassan
Full text: Acrobat
PDF (175 KB)
|
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.
|
|
15
|
Discrete Self-Similarity
between Rr Lyrae Stars And Singly-Excited Helium Atoms
Robert L. Oldershaw
Full text: Acrobat
PDF (137 KB)
|
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.
|
|
16
|
Brownian Dynamics of
Nanoparticles Moving Near a Fluctuating Membrane
A. Bendouch, M. Benhamou, and H.
Kaidi
Full text: Acrobat
PDF (187 KB)
|
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.
|
|
17
|
Influence of Third Order
Perturbation on Heisenberg Hamiltonian Of Thick Ferromagnetic Films
P. Samarasekara
Full text: Acrobat
PDF (197 KB)
|
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.
|
|
18
|
Viscous Dusty Fluid Flow with
Constant Velocity Magnitude
Siddabasappa, Venkateshappa,
Rudraswamy, Gopinath
Full text: Acrobat
PDF (467 KB)
|
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.
|
|
19
|
The Influence of Long-Range
Interaction on Critical Behavior of Some Alloys
S. V. Belim
Full text: Acrobat
PDF (124 KB)
|
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.
|
Volume 5, Issue 18 (June
2008)
Full text: Acrobat
PDF (949 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Liénard-Wiechert
Electromagnetic field
R. García-Olivo, R. Linares y M., J. López-Bonilla, and A. Rangel-Merino
Full text: Acrobat
PDF (178 KB)
|
The
electromagnetic field generated by a charge in arbitrary motion in
Minkowski space is briefly studied. Particularly important is the deduction
of the superpotential for the radiative part of Maxwell tensor.
|
|
2
|
On Conformal
d'Alembert-Like Equations
E. Capelas de Oliveira and R. da
Rocha
Full text: Acrobat
PDF (125 KB)
|
Using
conformal coordinates associated with projective conformal relativity we
obtain a conformal Klein-Gordon partial differential equation. As a
particular case we present and discuss a conformal `radial' d'Alembert-like
equation. As a by-product we show that this `radial' equation can be
identified with a one-dimensional Schr\"odinger-like equation in which
the potential is exactly the second P\"oschl-Teller potential.
|
|
3
|
Existence of Yang--Mills
Theory with Vacuum Vector and Mass Gap
Igor Hrncic
Full text: Acrobat
PDF (83 KB)
|
This
paper shows that quantum theory describing particles in finite expanding
space--time exhibits natural ultra--violet and infra--red cutoffs as well
as posesses a mass gap and a vacuum vector. Having ultra--violet and
infra--red cutoffs, all renormalization issues disappear. This shows that
Yang--Mills theory exists for any simple compact gauge group and has a mass
gap and a vacuum vector.
|
|
4
|
One-parameter potential from
Darboux Theorem
J García-Ravelo, J J Peña, J Morales, and
Shi-Hai Dong
Full text: Acrobat
PDF (128 KB)
|
We
consider the stationary one-dimensional Schrödinger equation with
potential u(x;i)=\sum\limits_{j=-2}^{2}f_{j}(i)x^{j}, where the
coefficients f_{j}(i) are functions of a discrete parameter i. We establish
the most general form of the coefficients f_{j}(i) and obtain the ladder
operators for the solution of Schrödinger equation by a Darboux
transform. Generally speaking, the Darboux transform is obtained through a
so-called superpotential W(x), which is derived from a Riccati equation. We
first propose a convenient \textit{ansatz} for the function % W^{\prime
}(x) and then yield a set of nine difference equations for the coefficients
f_{j}(i). This set of difference equations establishes the explicit form of
the coefficients f_{j}(i), in the potential u(x;i). Our results are
consistent with some well-known quantum potentials in special cases.
|
|
5
|
Group Properties of the Black
Scholes Equation and its Solutions
J. P. Singh and S. Prabakaran
Full text: Acrobat
PDF (131 KB)
|
Several
techniques of fundamental physics like quantum mechanics, field theory and
related tools of non-commutative probability, gauge theory, path integral
etc. are being applied for pricing of contemporary financial products and
for explaining various phenomena of financial markets like stock price
patterns, critical crashes etc.. The cardinal contribution of physicists to
the world of finance came from Fischer Black {\&} Myron Scholes through
the option pricing formula which bears their epitaph and which won them the
Nobel Prize for economics in 1997 together with Robert Merton and which
constitutes the cornerstone of contemporary valuation theory. They obtained
closed form expressions for the pricing of financial derivatives by
converting the problem to a heat equation and then solving it for specific
boundary conditions. In this paper, we apply the well-entrenched group
theoretic methods to obtain various solutions of the Black Scholes equation
for the pricing of contingent claims. We also examine the infinitesimal
symmetries of the said equation and explore group transformation
properties. The structure of the Lie algebra of the Black Scholes equation
is also studied.
|
|
6
|
Physical Invariants of
Intelligence
Michail Zak
Full text: Acrobat
PDF (218 KB)
|
The
objective of this work is to extend the physical invariants of biosignature
(from disorder to order) to invariants of intelligent behavior: {from
disorder to order via phase transition}. The approach is based upon the
extension of the physics' First Principles that includes behavior of living
systems. The new architecture consists of motor dynamics simulating actual
behavior of the object, and mental dynamics representing evolution of the
corresponding knowledge-base and incorporating it in the form of
information flows into the motor dynamics. Due to feedback from mental
dynamics, the motor dynamics attains quantum-like properties:its trajectory
splits into a family of different trajectories, and each of those
trajectories can be chosen with the probability prescribed by the mental
dynamics. Intelligence is considered as a tool to preserve and improve
survivability of Livings. From the viewpoint of mathematical formalism, it
can be associated with the capability to make decisions that {control} the
motor dynamics via a feedback from the {mental} dynamics by providing a
quantum-like collapse of a random motion into an appropriate deterministic
state. Special attention is focused on data-driven discovery of the
underlying physical model displaying an intelligent behavior within the
proposed formalism.
|
|
7
|
The Numbers Universe: an
outline of the Dirac/Eddington numbers as scaling factors for fractal,
black hole universes
Ross A. McPherson
Full text: Acrobat
PDF (116 KB)
|
The
large number coincidences that fascinated theorists such as Eddington and
Dirac are shown here to be a specific example of a general set of scaling
factors defining universes in which fundamental forces are equated. The
numbers have prescriptive power and they are therefore correct and exact {a
priori}. The universes thus defined exhibit a fractal structure centred on
the Planck/Stoney scale with some formal resemblance to black holes and
with properties analogous to Hawking radiation. The problematic case of
emerging and evaporating universes is briefly considered in the context of
quantum gravity. Historically, the large numbers are associated with the
mass of a charged particle and the mass of the universe. This paper
demonstrates that the numbers are properly understood in the context of
four masses including a non-zero mass derived from Hubble`s Constant and
the Planck or Stoney mass.
|
|
8
|
Quantum Analog of the Black-
Scholes Formula (market of financial derivatives as a continuous fuzzy
measurement
S. I. Melnyk, and I. G.
Tuluzov
Full text: Acrobat
PDF (104 KB)
|
We
analyze the properties of optimum portfolios, the price of which is
considered a new quantum variable and derive a quantum analog of the Black-Scholes
formula for the price of financial variables in assumption that the market
dynamics can by considered as its continuous weak measurement at
no-arbitrage condition.
|
|
9
|
Faster than Light Quantum
Communication
A.Y. Shiekh
Full text: Acrobat
PDF (150 KB)
|
Faster
than light communication might be possible using the collapse of the
quantum wave-function without any accompanying paradoxes.
|
|
10
|
Reply to `On a Recent
Proposal of Faster than Light Quantum Communication'
A.Y. Shiekh
Full text: Acrobat
PDF (105 KB)
|
In a recent paper [1] the author proposed the
possibility of an experiment to perform faster-than-light communication via
the collapse of the quantum wave-function. This was analyzed by Bassi and
Ghirardi [2], and it is believed that this analysis itself merits a
detailed examination.
|
Volume 5, Issue 19
(October 2008)
Full text: Acrobat
PDF 1,685 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Quantum Computing Through Quaternions
J. P. Singh and S. Prabakaran
Full text: Acrobat
PDF (112 KB)
|
Using
quaternions, we study the geometry of the single and two qubit states of
quantum computing. Through the Hopf fibrations, we identify geometric
manifestations of the separability and entanglement of two qubit quantum
systems.
|
|
2
|
Constructible Models of Orthomodular
Quantum Logics
Piotr WILCZEK
Full text: Acrobat
PDF (246 KB)
|
We
continue in this article the abstract algebraic treatment of quantum
sentential logics [39]. The Notions borrowed from the field of Model Theory
and Abstract Algebraic Logic - AAL (i.e., consequence relation, variety,
logical matrix, deductive filter, reduced product, ultraproduct,
ultrapower, Frege relation, Leibniz congruence, Suszko congruence, Leibniz
operator) are applied to quantum logics. We also proved several
equivalences between state property systems (Jauch-Piron-Aerts line of
investigations) and AAL treatment of quantum logics (corollary 18 and 19).
We show that there exist the uniquely defined correspondence between state
property system and consequence relation defined on quantum logics. We also
signalize that a metalogical property - Lindenbaum property does not hold
for the set of quantum logics.
|
|
3
|
Quantum Size Effect of Two Couple Quantum Dots
Gihan H. Zaki, Adel H. Phillips and Ayman S. Atallah
Full text: Acrobat
PDF (108 KB)
|
The
quantum transport characteristics are studied for double quantum dots
encountered by quantum point contacts. An expression for the conductance is
derived using Landauer - Buttiker formula. A numerical calculation shows
the following features: (i) Two resonance peaks appear for the dependence
of normalized conductance, G, on the bias voltage, V$_{0}$, for a certain
value of the inter barrier thickness between the dots. As this barrier
thickness increases the separation between the peaks decreases. (ii) For the
dependence of, G, on, Vo, the peak heights decrease as the outer barrier
thickness increases. (iii) The conductance, G, decreases as the temperature
increases and the calculated activation energy of the electron increases as
the dimension, b, increases. Our results were found concordant with those
in the literature.
|
|
4
|
Quantum Destructive Interference
A.Y. Shiekh
Full text: Acrobat
PDF (113 KB)
|
An
apparent paradox for unitarity non-conservation is investigated for the
case of destructive quantum interference.
|
|
5
|
Quantized Fields Around Field Defects
Bakonyi G.
Full text: Acrobat
PDF (98 KB)
|
A
heuristic exercise exploring analogies between different field theories.
Similarities between the crystal defects and other various fields help to
create a model to quantize these fields. The charge of the electromagnetic
field and the electromagnetic waves are used as examples.
|
|
6
|
Path Integral Quantization of Brink-Schwarz
Superparticle
N. I. Farahat, and H. A. Elegla
Full text: Acrobat
PDF (94 KB)
|
The
quantization of the Brink-Schwarz superparticle is performed by canonical
phase-space path integral.The supersymmetric particle is treated as a
constrained system using the Hamilton-Jacobi approach. Since the equations
of motion are obtained as total differential equations in many variables,
we obtained the canonical phase space coordinates and the phase space
Hamiltonian with out introducing Lagrange multipliers and with out any
additional gauge fixing condition.
|
|
7
|
Noncommutative Geometry and Modified Gravity
N. Mebarki and F. Khelili
Full text: Acrobat
PDF (145 KB)
|
Using
noncommutative deformed canonical commutation relations, a model of gravity
is constructed and a schwarchild like static solutions are obtained. As a
consequence, the Newtonian potential is modified and it is shown to have a
form similar to the one postulated by Fishbach et al. to explain the
proposed fifth force. More interesting is the form of the gravitational
acceleration expression proposed in the modified Newtonian dynamics
theories (MOND) which is obtained explicitly in our model without any ad
hoc asymptions.
|
|
8
|
Classification of Electromagnetic Fields in
non-Relativist Mechanics
N. Sukhomlin and M.
Arias
Full text: Acrobat
PDF (124 KB)
|
We
study the classification of electromagnetic fields using the equivalence
relation on the set of all 4-potentials of the Schr\"odinger
equation. In the general case
we find the relations among the equivalent fields, currents, and charge
densities. Particularly, we
study the fields equivalent to the null field. We show that the non-stationary
state function for a particle in arbitrary uniform time-dependent magnetic
field is equivalent to a plane wave.
We present that the known coherent states of a free particle are
equivalent to the stationary states of an isotropic oscillator. We reveal that the only constant
magnetic field is not equivalent to the null field (contrary to a constant
electrical field) and we find other fields that are equivalent to the
constant magnetic field. We
establish that one particular transformation of the free Schr\"odinger
equation puts a plane wave and Green's function in a equivalence relation.
|
|
9
|
Magnetized Bianchi Type VI_0
Barotropic Massive String Universe with Decaying Vacuum Energy Density
\Lambda.
Anirudh Pradhan and Raj Bali
Full text: Acrobat
PDF (124 KB)
|
Bianchi
type VI_0 massive string cosmological models using the technique given by
Letelier (1983) with magnetic field are investigated. To get the
deterministic models, we assume that the expansion (\theta) in the model is
proportional to the shear (\sigma) and also the fluid obeys the barotropic
equation of state. It was found that vacuum energy density \Lambda \propto
\frac{1}{t^{2}} which matches with natural units. The behaviour of the
models from physical and geometrical aspects in presence and absence of
magnetic field is also discussed.
|
|
10
|
Bianchi Type V Magnetized
String Dust Universe with Variable Magnetic Permeability
Raj Bali
Full text: Acrobat
PDF (103 KB)
|
Bianchi
Type V magnetized string dust universe with variable magnetic permeability
is investigated. The magnetic field is due to an electric current produced
along x-axis. Thus F_{23} is the only non-vanishing component of
electro-magnetic field tensor F_{ij}. Maxwell's equations F_{[ij;k]} = 0,
F_{;j}^{ij} = 0 are satisfied by F_{23} =constant. The physical and geometrical
aspects of the model with singularity in the model are discussed. The
physical implications of the model are also explained.
|
|
11
|
Dynamics of Shell With a
Cosmological Constant
A. Eid
Full text: Acrobat
PDF (102 KB)
|
Spherically symmetric thin
shell in the presence of a cosmological constant are constructed, applying
the Darmois-Israel formalism. An equation governing the behavior of the
radial pressure across the junction surface is deduced. The cosmological
constant term slows down the collapse of matter. The spherical N-shell
model with an appropriate initial condition imitates the FRW universe with
\Lambda \ne 0, quite well.
|
|
12
|
Discrete Cosmological
Self-Similarity and Delta Scuti Variable Stars
Robert L. Oldershaw
Full text: Acrobat
PDF (97 KB)
|
Within the context of a
fractal paradigm that emphasizes nature's well-stratified hierarchical
organization, the \delta Scuti class of variable stars is investigated for
evidence of discrete cosmological self-similarity. Methods that were
successfully applied to the RR Lyrae class of variable stars are used to
identify Atomic Scale analogues of \delta Scuti stars and their relevant range
of energy levels. The mass, pulsation mode and fundamental oscillation
period of a well-studied \delta
Scuti star are then shown to be quantitatively self-similar to the
counterpart parameters of a uniquely identified Atomic Scale analogue.
Several additional tests confirm the specificity of the discrete fractal
relationship.
|
|
13
|
Neutrino Mixings and Magnetic
Moments Due to Planck Scale Effects
Bipin Singh Koranga
Full text: Acrobat
PDF (101 KB)
|
In this paper, we consider
the effect of Planck scale operators on neutrino magnetic moments. We
assume that the main part of neutrino masses and mixings arise through GUT
scale operators. We further assume that additional discrete symmetries make
the neutrino mixing bi-maximal. Quantum gravitational (Planck scale)
effects lead to an effective SU(2)_{L}\times U(1) invariant dimension-5
Lagrangian involving neutrino and Higgs fields, which gives rise to
additional terms in neutrino mass matrix. These additional terms can be
considered to be perturbation of the GUT scale bi-maximal neutrino mass
matrix. We assume that the gravitational interaction is flavor blind and we
study the neutrino mixings and magnetic moments due to the physics above
the GUT scale.
|
|
14
|
Casimir Force in Confined
Crosslinked Polymer Blends
M. Benhamou, A. Agouzouk, H. Kaidi,
M. Boughou, S. El Fassi, and A. Derouiche
Full text: Acrobat
PDF (169 KB)
|
The physical system we
consider is a crosslinked polymer blend (or an interpenetrating polymer
network), made of two chemically incompatible polymers, which are confined
to two parallel plates that are a finite distance L apart, that is L<\xi
^{*}. Here, \xi^{*}\thicksim aD^{-1/2} (a being the monomer size and D the
reticulation dose) denotes the size of the microdomains (mesh size). We
assume that these strongly adsorb one or the two polymers, near the
spinodal temperature (critical adsorption).\ The strong fluctuations of
composition give rise to an induced force between the walls we are
interested in. To compute this force, as a function of the separation L, we
elaborate a field model, of which the free energy is a functional of the
composition fluctuation (order parameter). Within the framework of this
extended de Gennes theory, we exactly compute this induced force, for two
special boundary conditions (symmetric and asymmetric plates). Symmetric
plates mean that these have the same preference to adsorb one polymer,
while asymmetric ones correspond to the situation where one polymer adsorbs
onto the first plate and the other onto the second one. Using the {\em
phase portrait} % method, we first show that the induced force is {\em
attractive}, for symmetric plates, and {\em repulsive}, for asymmetric
ones. Second, we demonstrate that the force satisfies the scaling laws: \Pi
_a=\Pi_a^0.\Omega _a\left( L/\xi ^{*}\right) (symmetric plates) and \Pi _r=\Pi
_r^0.\Omega _r\left( L/\xi ^{*}\right)
(asymmetric plates). Here, \Omega_a\left( x\right) and \Omega
_r\left( x\right) are {\em
known}universal scaling functions, where \Pi _a^0=-E_aL^{-4} and
\Pi_r^0=E_rL^{-4} are the induced forces relative to an uncrosslinked polymer
blend confined to the same geometry (E_a and E_r are known amplitudes).\
For very small distances compared to the mesh size \xi ^{*}, we show that,
in any case, the force decays exponentially, that is : \Pi _a\simeq
-E_aL^{-4}\exp \left\{ -L^2/\xi ^{*\text{ }2}\right\} and \Pi _r\simeq E_rL^{-4}\exp
\left\{ -L^2/\xi ^{*\text{ }2}\right\} . Finally, this work must be
regarded as a natural extension of that relative to the uncrosslinked
polymer blends.
|
|
15
|
Transport Properties of
Thermal Shot Noise Through Superconductor-Ferromagnetic 2DEG Junction
Attia A. Awad Alla, and Adel H.
Phillips
Full text: Acrobat
PDF (306 KB)
|
We study transport
properties of thermal shot noise, thermo power and thermal conductance
through superconductor-ferromagnetic /2DEG junction under the effect of
Fermi energy, number of open channels and excitation energy. Thermal shot
noise, P_{Thermal} is directly related to the conductance through the
fluctuation- dissipation theorem; the model consists of a 2DEG region
inserted between two identical superconductor electrodes. Ferromagnetic
strips are placed onto top of each superconductor/2DEG junction and voltage
applied across the model. The results show an oscillatory behavior of the
dependence of the thermal shot noise on Fermi energy. These results agree
with existing experiments. This research is very important for using a
model as a high-frequency shot noise detector.
|
|
16
|
On the Genuine Bound States
of a Non-Relativistic Particle in a Linear Finite Range
Potential
Nagalakshmi A. Rao and B. A. Kagali
Full text: Acrobat
PDF (169 KB)
|
We explore the energy
spectrum of a non-relativistic particle bound in a linear finite range,
attractive potential, envisaged as a quark-confining potential. The intricate
transcendental eigenvalue equation is solved numerically to obtain the
explicit eigen-energies. The linear potential, which resembles the
triangular well, has potential significance in particle physics and
exciting applications in electronics.
|
|
17
|
Exact Non-traveling Wave and
Coefficient Function Solutions for (2+1)-Dimensional
Dispersive Long Wave
Equations
Sheng Zhang, Wei Wang, and Jing-Lin
Tong
Full text: Acrobat
PDF (209 KB)
|
In this paper, a new
generalized F-expansion method is proposed to seek exact solutions of
nonlinear evolution equations. With the aid of symbolic computation, we
choose the (2+1)-dimensional dispersive long wave equations to illustrate
the validity and advantages of the proposed method. As a result, many new
and more general exact non-traveling wave and coefficient function
solutions are obtained including single and combined non-degenerate Jacobi
elliptic function solutions, soliton-like solutions and trigonometric
function solutions, each of which contains two arbitrary functions. The
arbitrary functions provide us with enough freedom to discuss the behaviors
of solutions. As an illustrative example, new spatial structures of two
solutions are shown. Compared with the most existing F-expansion methods,
the new generalized F-expansion method gives not only more general exact
solutions but also new formal exact solutions. The proposed method can also
be applied to other nonlinear evolution equations in mathematical physics.
|
Volume 6, Issue 20
(February 2009)
Full text: Acrobat
PDF 2,811 KB)
|
Number
|
Articles Title
|
Abstract
|
|
1
|
Macroscopically-Discrete Quantum Cosmology
Geoffrey F. Chew
Full text: Acrobat
PDF (232 KB)
|
Milne's
Lorentz-group-based cosmological spacetime and Gelfand-Naimark unitary
Lorentz-group representation through transformation of Hilbert-space
vectors combine to define a Fock space of `cosmological
preons'---quantum-theoretic universe constituents. Lorentz invariance of
`age'--\textit{global} \textit{time}-- accompanies Milne's `cosmological
principle' that attributes to each spatial location a Lorentz frame. We
divide Milne spacetime---the interior of a forward lightcone-- into
`slices' of fixed \textit{macroscopic} width in age, with `cosmological
rays' defined on (hyperbolic) \textit{slice} \textit{boundaries}. The Fock
space of our macroscopically-discrete quantum cosmology (DQC) is defined
\textit{only} at these \textit{exceptional} universe ages. Self-adjoint-operator
expectations over the ray at any spacetime-slice boundary prescribe
throughout the following slice a non-fluctuating continuous `classical
reality' represented by Dalembertians, of classical electromagnetic
(vector) and gravitational (tensor) potentials, that are current densities
of locally-conserved electric charge and energy-momentum. The ray at the
upper boundary of a slice is determined from the lower-boundary ray by
\textit{branched} slice-traversing \textit{stepped} Feynman paths that carry
potential-depending action. Path step is at Planck-scale; branching points
represent preon creation-annihilation. Each single-preon wave function
depends on the coordinates of a 6-dimensional manifold, one of whose
`extra' dimensions associates in Dirac sense to a self-adjoint operator
that represents the preon's reversible \textit{local} time. Within a path,
local-time \textit{intervals} equal corresponding intervals of
monotonically-increasing global time even though, within a
(\textit{fixed-age}) ray, the local time of a preon is variable. The
operator canonically conjugate to a preon's local time represents its
(total) energy in its (Milne) `local frame'. A macroscopically-stable
positive-energy single-preon wave function identifies either with a Standard-Model
elementary particle or with a graviton. Within intermediate-density
sub-Hubble-scale universe regions such as the solar system, where
`reproducible measurement' is meaningful, \textit{physical} special
relativity---`Poincar\'{e} invariance'---approximates DQC for spacetime
scales far above that of Planck.
|
|
2
|
Nonholonomic Ricci Flows: Exact Solutions
and Gravity
Sergiu I. Vacaru
Full text: Acrobat
PDF (281 KB)
|
In
a number of physically important cases, the nonholonomically
(nonintegrable) constrained Ricci flows can be modelled by exact solutions
of Einstein equations with nonhomogeneous (anisotropic) cosmological
constants. We develop two geometric methods for constructing such
solutions: The first approach applies the formalism of nonholonomic frame
deformations when the gravitational evolution and field equations transform
into systems of nonlinear partial differential equations which can be
integrated in general form. The second approach develops a general scheme
when one (two) parameter families of exact solutions are defined by any
source—free solutions of Einstein's equations with one (two) Killing
vector field(s). A successive iteration procedure results in a class of
solutions characterized by an infinite number of parameters for a
non--Abelian group involving arbitrary functions on one variable. We also
consider nonlinear superpositions of some mentioned classes of solutions in
order to construct more general integral varieties of the Ricci flow and
Einstein equations depending on infinite number of parameters and
three/four coordinates on four/ five dimensional (semi) Riemannian spaces.
|
|
3
|
Killing Symmetries of Deformed Relativity in Five
Dimensions
Fabio Cardone, Alessio Marrani and Roberto Mignani
Full text: Acrobat
PDF (742 KB)
|
This
is the first of two papers devoted to investigating the main mathematical
aspects of the Kaluza-Klein-like scheme known as Deformed Relativity in
five dimensions (DR5). It is based on a five-dimensional Riemannian space
in which the four-dimensional space-time metric is deformed (i.e. it
depends on the energy) and energy plays the role of the fifth dimension.
After a brief survey of the physical and mathematical foundations of DR5,
we discuss in detail the Killing symmetries of the theory. In particular,
we consider the case of physical relevance in which the metric coefficients
are power functions of the energy (Power Ansatz). In order to solve the
related Killing equations, we introduce a simplifying hypothesis of
functional independence ($\Upsilon $ hypothesis). The explicit expressions
of the Killing vectors for the energy-dependent metrics corresponding to
the four fundamental interactions (electromagnetic, weak, strong and
gravitational) are derived. A preliminary discussion of the
infinitesimal-algebraic structure of the Killing symmetries of DR5 is also
given.
|
|
4
|
Non commutative Lemaitre-Tolman-Bondi like Metric
and Cosmology
N.Mebarki, F.Khelili, H.Bouhalouf and O.Mebarki
Full text: Acrobat
PDF (161 KB)
|
Using
noncommutative deformed canonical commutation relations, a model describing
gravitation is constructed. A noncommutative Lemaitre- Tolman-Bondi like
metric is proposed and non static solutions are discussed. It turns out
that in spite of its smallness, the noncommutativity of the geometry plays
an important role in unifying the dark matter and | |