title: Weber-Fechner's Law and Demand Function

abstract:
  We apply the Weber-Fechner's law, which represents the relation between the
magnitude of physical stimulus and the magnitude of psychological sense in
human being, to the utility function. We conclude that the utility function of
n-types of goods is of separable type u(x_1,x_2,..., x_n)=u_1(x_1)+u_2(x_2)+...
+u_n(x_n), which give the relation of the demand function in the form p_i=d
u_i/d x_i. The explicit quantitative form of each utility function, which is
suggested by the Weber-Fechner's law, becomes u_i(x_i)=A_i \log
(x_i/x^{(0)}_i). Then we obtain each demand function in the familiar form
p_i=A_i/x_i.


title: Surface-active dust in a plasma sheath

abstract:
  The inhomogeneity of the plasma pressure near a conducting electrode is a
cause for introducing the surface tension associated with the plasma-electrode
interface. We evaluate the dependence of the surface tension on the density of
the charged dust immersed in the plasma sheath. In a wide range of parameters,
the surface tension turns out to be an increasing function of the dust density.


title:
Analytical study of the effect of recombination on evolution via DNA
  shuffling

abstract:
  We investigate a multi-locus evolutionary model which is based on the DNA
shuffling protocol widely applied in \textit{in vitro} directed evolution. This
model incorporates selection, recombination and point mutations. The simplicity
of the model allows us to obtain a full analytical treatment of both its
dynamical and equilibrium properties, for the case of an infinite population.
We also briefly discuss finite population size corrections.


title:
On physical nature of radiation regulating quantity of cells in
  population

abstract:
  It is shown, that spontaneous ultraviolet radiation of cells (infusoria)
plays the role of agent, restricting the upper limit of the quantity of cells
in quasi-stationary phase of cultire's development. The spectral region of this
radiation defined experimentally occurred to be in the range of 200-290 nm. As
the filter cutting off the short wave length part of the spectrum (below 290nm)
1 mm thick plexiglas has been used, while as the filters transmitting short
wave part of the spectrum - 5 mkm thick fluorostatic film or 1 mm thick optical
quartz has been selected. It has been shown, that dynamics of development of
the cells in the culture depends on transparency of nutrient medium to
spontaneous ultraviolet radiation of the cells. Conclusion has been made, that
superweak chemiluminescence of the cells is not a worthless metabolism product,
but plays significant biological role.


title: Dynamic Point-Formation in Dielectric Fluids

abstract:
  We use boundary-integral methods to compute the time-dependent deformation of
a drop of dielectric fluid immersed in another dielectric fluid in a uniform
electric field E. Steady state theory predicts, when the permittivity ratio,
\beta, is large enough, a conical interface can exist at two cone angles, with
\theta_<(\beta) stable and \theta_>(\beta) unstable. Our numerical evidence
instead shows a dynamical process which produces a cone-formation and a
transient finite-time singularity, when E and \beta are above their critical
values. Based on a scaling analysis of the electric stress and the fluid
motion, we are able to apply approximate boundary conditions to compute the
evolution of the tip region. We find in our non-equilibrium case where the
electric stress is substantially larger than the surface tension, the ratio of
the electric stress to the surface tension in the newly-grown cone region can
converge to a \beta dependent value, \alpha_c(\beta)>1, while the cone angle
converges to \theta_<(\beta). This new dynamical solution is self-similar.


title:
Charged Grains In Saturn's F-Ring: Interaction With Saturn's Magnetic
  Field

abstract:
  Saturn's dynamic F-Ring still presents a challenge for understanding and
explaining the kinematic processes that lead to the changing structure visible
in our observations of this ring. This study examines the effect of Saturn's
magnetic field on the dynamics of micron-sized grains that may become
electrically charged due to interaction with plasma in Saturn's rigidly
corotating magnetosphere. The numerical model calculates the dynamics of
charged dust grains and includes forces due to Saturn's gravitational field,
the plasma polarization electric field, a third order harmonic expansion of
Saturn's magnetic field, and the F Ring's Shepherding moons, Prometheus and
Pandora.


title:
Gravitoelectrodynamics in Saturn's F Ring: Encounters with Prometheus
  and Pandora

abstract:
  The dynamics of Saturn's F Ring have been a matter of curiosity ever since
Voyagers 1 and 2 sent back pictures of the ring's unusual features. Some of
these images showed three distinct ringlets with the outer two displaying a
kinked and braided appearance. Many models have been proposed to explain the
braiding seen in these images; most of these invoke perturbations caused by the
shepherding moons or km sized moonlets imbedded in the ring and are purely
gravitational in nature. These models also assume that the plasma densities and
charges on the grains are small enough that electromagnetic forces can be
ignored. However, Saturn's magnetic field exerts a significant perturbative
force on even weakly charged micron and sub-micron sized grains causing the
grains to travel in epicyclic orbits about a guiding center. This study
examines the effect of Saturn's magnetic field on the dynamics of micron-sized
grains along with gravitational interactions between the F Ring's shepherding
moons, Prometheus and Pandora. Due to differences in the charge-to-mass ratios
of the various sized grains, a phase difference between different size
populations is observed in the wavy orbits imposed by passage of the
shepherding moons.


title:
The focus of light - linear polarization breaks the rotational symmetry
  of the focal spot

abstract:
  We experimentally demonstrate for the first time that a linearly polarized
beam is focussed to an asymmetric spot when using a high-numerical aperture
focussing system. This asymmetry was predicted by Richards and Wolf
[Proc.R.Soc.London A, 253, 358 (1959)] and can only be measured when a
polarization insensitive sensor is placed in the focal region. We used a
specially modified photodiode in a knife edge type set up to obtain highly
resolved images of the total electric energy density distribution at the focus.
The results are in good agreement with the predictions of a vectorial focussing
theory.


title:
Q factor in numerical simulations of DPSK with optical delay
  demodulation

abstract:
  A simple model is used to estimate the Q factor in numerical simulations of
differential phase shift keying (DPSK) with optical delay demodulation and
balanced detection. It is found that an alternative definition of Q is needed
for DPSK in order to have a more accurate prediction of the bit error ratio
(BER).


title: Reading Neural Encodings using Phase Space Methods

abstract:
  Environmental signals sensed by nervous systems are often represented in
spike trains carried from sensory neurons to higher neural functions where
decisions and functional actions occur. Information about the environmental
stimulus is contained (encoded) in the train of spikes. We show how to "read"
the encoding using state space methods of nonlinear dynamics. We create a
mapping from spike signals which are output from the neural processing system
back to an estimate of the analog input signal. This mapping is realized
locally in a reconstructed state space embodying both the dynamics of the
source of the sensory signal and the dynamics of the neural circuit doing the
processing. We explore this idea using a Hodgkin-Huxley conductance based
neuron model and input from a low dimensional dynamical system, the Lorenz
system. We show that one may accurately learn the dynamical input/output
connection and estimate with high precision the details of the input signals
from spike timing output alone. This form of "reading the neural code" has a
focus on the neural circuitry as a dynamical system and emphasizes how one
interprets the dynamical degrees of freedom in the neural circuit as they
transform analog environmental information into spike trains.


title:
Cosmological Consequences of the Yukawa Potential Involvement in
  Gravitational and Electromagnetic Fields Interaction Evaluated by ENU Model

abstract:
  Model of Expansive Nondecelerative Universe (ENU) due to involving Vaidya
metric makes it possible to localize the energy density of gravitational field.
This its capability allows for answering several open questions and supporting
(or contradicting) results obtained using different theoretical approaches.
This paper is aimed to contributing to a solution of some cosmological
problems, in particular those linked to the Yukawa potential consequences,
independent way of dark matter estimation, ionospheric F2 layer behaviour, and
cyclotron radiation.


title: Pairing of fermions in atomic traps and nuclei

abstract:
  Pairing gaps for fermionic atoms in harmonic oscillator traps are calculated
for a wide range of interaction strengths and particle number, and compared to
pairing in nuclei. Especially systems, where the pairing gap exceeds the level
spacing but is smaller than the shell splitting $\hbar\omega$, are studied
which applies to most trapped Fermi atomic systems as well as to finite nuclei.
When solving the gap equation for a large trap with such multi-level pairing,
one finds that the matrix elements between nearby harmonic oscillator levels
and the quasi-particle energies lead to a double logarithm of the gap, and a
pronounced shell structure at magic numbers. It is argued that neutron and
proton pairing in nuclei belongs to the class of multi-level pairing, that
their shell structure follows naturally and that the gaps scale as $\sim
A^{-1/3}$ - all in qualitative agreement with odd-even staggering of nuclear
binding energies. Pairing in large systems are related to that in the bulk
limit. For large nuclei the neutron and proton superfluid gaps approach the
asymptotic value in infinite nuclear matter: $\Delta\simeq 1.1$ MeV.

categories: physics.atom-ph cond-mat.supr-con nucl-th physics.gen-ph


title: The Relativistic Rotation

abstract:
  The classical rotation is not self-consistent in the framework of the special
theory of relativity. the Relativistic rotation is obtained, which takes the
relativistic effect into account. It is demonstrated that the angular frequency
of classical rotation is only valid in local approximation. The properties of
the relativistic rotation and the relativistic transverse Doppler shift are
discussed in this work.


title:
Is it possible to obtain polarized positrons during multiple Compton
  backscattering process?

abstract:
  If a beam of unpolarized positrons (which is considered as a sum of two
fractions with opposite helicities) passes through an intense circular
polarized laser radiation these fractions may be separated. For high laser
flash intensity each positron will interact with $k_0\gg$1 laser photons
subsequently (linear multiple compton scattering process). Due to difference in
the compton cross-section for positrons polarized in opposite directions the
mean final energy of each fraction will be different. It allows to get a
polarized positron beam using the momentum selection (with some intensity
loss). Estimations show the possibility to obtain a positron beam with 35%
longitudinal polarization and 25% intensity from the initial one for focussed
laser flash with total energy 5J and positron beam with energy 5 GeV.


title:
The theoretical simulation of optical properties of crystals with
  statistically disordered arrangement of atoms and atomic groups on the basis
  of point-dipole model

abstract:
  With using of point-dipole model the theoretical calculations of main
refractive indices and orientation of indicatrix of 18 minerals are performed.
The feature of studied minerals is the statistically disordered arrangement of
CO3, SO4, SO2, PO4 groups and also separate ions. The optical characters of
uniaxial minerals and orientation of indicatrix of orthorhombic and monoclinic
minerals, obtained by results of calculations, agree with experimental
definitions.


title:
Noise sensitivity of sub- and supercritically bifurcating patterns with
  group velocities close to the convective-absolute instability

abstract:
  The influence of small additive noise on structure formation near a forwards
and near an inverted bifurcation as described by a cubic and quintic Ginzburg
Landau amplitude equation, respectively, is studied numerically for group
velocities in the vicinity of the convective-absolute instability where the
deterministic front dynamics would empty the system.


title: Wave propagation in a chiral fluid: an undergraduate study

abstract:
  We study the propagation of electromagnetic waves in a chiral fluid, where
the molecules are described by a simplified version of the Kuhn coupled
oscillator model. The eigenmodes of Maxwell's equations are circularly
polarized waves. The application of a static magnetic field further leads to a
magnetochiral term in the index of refraction of the fluid, which is
independent of the wave polarization. A similar result holds when absorption is
taken into account. Interference experiments and photochemical reactions have
recently demonstrated the existence of the magnetochiral term. The comparison
with Faraday rotation in an achiral fluid emphasizes the different symmetry
properties of the two effects.


title: Stochastic dynamics of the magneto-optical trap

abstract:
  The cloud of cold atoms obtained from a magneto-optical trap is known to
exhibit two types of instabilities in the regime of high atomic densities:
stochastic instabilities and deterministic instabilities. In the present paper,
the experimentally observed stochastic dynamics is described extensively. It is
shown that it exists a variety of dynamical behaviors, which differ by the
frequency components appearing in the dynamics. Indeed, some instabilities
exhibit only low frequency components, while in other cases, a second time
scale, corresponding to a higher frequency, appears in the motion of the center
of mass of the cloud. A one-dimensional stochastic model taking into account
the shadow effect is shown to be able to reproduce the experimental behavior,
linking the existence of instabilities to folded stationary solutions where
noise response is enhanced. The different types of regimes are explained by the
existence of a relaxation frequency, which in some conditions is excited by
noise.


title:
Shortcut to a Fermi-Degenerate Gas of Molecules via Cooperative
  Association

abstract:
  We theoretically examine the creation of a Fermi-degenerate gas of molecules
via a photoassociation or Feshbach resonance applied to a degenerate Bose-Fermi
mixture of atoms. This problem raises an interest because, unlike bosons,
fermions in general do not behave cooperatively, so that the collective
conversion of, say, two million atoms into one million molecules is not to be
expected. Nevertheless, we find that the coupled Fermi system displays
collective Rabi-like oscillations and adiabatic passage between atoms and
molecules, thereby mimicking Bose-Einstein statistics. Cooperative association
of a degenerate mixture of Bose and Fermi gases could therefore serve as a
shortcut to a degenerate gas of Fermi molecules.

categories: physics.atom-ph cond-mat.soft cond-mat.stat-mech physics.chem-ph quant-ph


title: Tests for non-randomness in quantum jumps

abstract:
  In a fundamental test of quantum mechanics, we have observed 228~000 quantum
jumps of a single trapped and laser cooled $^{88}$Sr$^+$ ion. This represents a
statistical increase of two orders of magnitude over previous similar analyses
of quantum jumps. Compared to other searches for non-randomness in quantum
mechanical processes, using quantum jumps simplifies the interpretation of data
by eliminated multi-particle effects and providing near-unit detection
efficiency of transitions. We measure the fractional reduction in the entropy
of information to be $< 6.5~10^{-4}$ when the value of any interval between
quantum jumps is known. We also find that the number of runs of successively
increasing or decreasing interval times agrees with the theoretically expected
values. Furthermore, we analyze 238~000 quantum jumps from two simultaneously
confined ions and find that the number of apparently coincidental transitions
is as expected. Finally, we observe 8400 spontaneous decays of two
simultaneously trapped ions and find that the number of apparently coincidental
decays from the metastable state agrees with the expected value. We find no
evidence for short- or long-term correlations in the intervals of the quantum
jumps or in the decay of the quantum states, in agreement with quantum theory.


title:
S-Link to Gigabit Ethernet Adapter New Frame Segmentation for LHCb Data
  Acquisition System

abstract:
  Data Acquisition and Control Systems used in high energy physics experiments,
such as those which will take place in the Large Hadron Collider (LHC) at CERN,
require the specification of data formats and transmission protocols as well as
the use of high speed links and interfaces.
  In this context, a new Frame Segmentation process will be presented and
discussed, based on data formats adopted by the LHCb experience for the
interconnection of two standardized systems: S-link and Gigabit Ethernet.
Simulation results of the transfer capacity of the proposed mechanism will be
also reported, together with guidelines for its physical implementation.


title: The Rotating Magnet

abstract:
  Axisymmetric permanent magnets become electrically polarized due to their
rotation around the symmetry axis. This phenomenon is considered in detail for
both conducting and dielectric magnets. The results are applied to the Earth
which is predicted to be electrically polarized. It is suggested that this
polarization can be detected in a tethered satellite experiment.


title:
Genetic Algorithms for the Imitation of Genomic Styles in Protein
  Backtranslation

abstract:
  Several technological applications require the translation of a protein into
a nucleic acid that codes for it (``backtranslation''). The degeneracy of the
genetic code makes this translation ambiguous; moreover, not every translation
is equally viable. The common answer to this problem is the imitation of the
codon usage of the target species. Here we discuss several other features of
coding sequences (``coding statistics'') that are relevant for the ``genomic
style'' of different species. A genetic algorithm is then used to obtain
backtranslations that mimic these styles, by minimizing the difference in the
coding statistics. Possible improvements and applications are discussed.


title: The boundary and continual transfer phenomena in fluids and flows

abstract:
  The clearing up of a wave nature of the energy and mass transfer phenomena in
classical expressions of the molecular-kinetic theory has allowed to find a
quantitative measure of intensity of processes of a thermal conductivity,
viscosity and diffusion in conditions of a thermally nonequilibrium and
heterogeneous composition continuum. It is rotined that the appearance of a
temperature drop in fluid stipulates the appearance of the continuum
stratification and formation of the flowing bodies interacting among
themselves. It is rotined that the known expressions for a thermal
conductivity, viscosity, diffusion and heat convection had been obtained for a
thermally equilibrium and homogeneous continuum and produce a maximum quantity
of intensity of the transfer processes. The introduced expression is usable for
a quantitative estimation of intensity of the transfer processes in fluid and
its streams in conditions of the non-stationary heat exchange in natural
conditions and technical problems.


title:
Brussels-Austin Nonequilibrium Statistical Mechanics in the Early Years:
  Similarity Transformations between Deterministic and Probabilistic
  Descriptions

abstract:
  The fundamental problem on which Ilya Prigogine and the Brussels-Austin Group
have focused can be stated briefly as follows. Our observations indicate that
there is an arrow of time in our experience of the world (e.g., decay of
unstable radioactive atoms like Uranium, or the mixing of cream in coffee).
Most of the fundamental equations of physics are time reversible, however,
presenting an apparent conflict between our theoretical descriptions and
experimental observations. Many have thought that the observed arrow of time
was either an artifact of our observations or due to very special initial
conditions. An alternative approach, followed by the Brussels-Austin Group, is
to consider the observed direction of time to be a basics physical phenomenon
and to develop a mathematical formalism that can describe this direction as
being due to the dynamics of physical systems. In part I of this essay, I
review and assess an attempt to carry out an approach that received much of
their attention from the early 1970s to the mid 1980s. In part II, I will
discuss their more recent approach using rigged Hilbert spaces.


title: GPCALMA, a mammographic CAD in a GRID connection

abstract:
  Purpose of this work is the development of an automatic system which could be
useful for radiologists in the investigation of breast cancer. A breast
neoplasia is often marked by the presence of microcalcifications and massive
lesions in the mammogram: hence the need for tools able to recognize such
lesions at an early stage. GPCALMA (Grid Platform Computer Assisted Library for
MAmmography), a collaboration among italian physicists and radiologists, has
built a large distributed database of digitized mammographic images (at this
moment about 5500 images corresponding to 1650 patients). This collaboration
has developed a CAD (Computer Aided Detection) system which, installed in an
integrated station, can also be used for digitization, as archive and to
perform statistical analysis. With a GRID configuration it would be possible
for the clinicians tele- and co-working in new and innovative groupings
('virtual organisations') and, using the whole database, by the GPCALMA tools
several analysis can be performed. Furthermore the GPCALMA system allows to be
abreast of the CAD technical progressing into several hospital locations always
with remote working by GRID connection. We report in this work the results
obtained by the GPCALMA CAD software implemented with a GRID connection.


title:
Brussels-Austin Nonequilibrium Statistical Mechanics in the Later Years:
  Large Poincare Systems and Rigged Hilbert Space

abstract:
  This second part of a two-part essay discusses recent developments in the
Brussels-Austin Group after the mid 1980s. The fundamental concerns are the
same as in their similarity transformation approach (see Part I), but the
contemporary approach utilizes rigged Hilbert space (whereas the older approach
used Hilbert space). While the emphasis on nonequilibrium statistical mechanics
remains the same, the use of similarity transformations shifts to the
background. In its place arose an interest in the physical features of large
Poincar\U{e9} systems, nonlinear dynamics and the mathematical tools necessary
to analyze them.


title:
Internet websites statistics expressed in the framework of the
  Ursell-Mayer cluster formalism

abstract:
  We show that it is possible to generalize the Ursell-Mayer cluster formalism
so that it may cover also the statistics of Internet websites. Our starting
point is the introduction of an extra variable that is assumed to take account,
as will be explained, of the nature of the Internet statistics. We then show,
following the arguments in Mayer, that one may obtain a phase transition-like
phenomena


title: Electromagnetic pulses which have a zero momentum frame

abstract:
  One set of the Ziolkowski family of exact solutions of the wave equation are
shown to represent pulses propagating with momentum smaller than energy/c. This
is explicitly demonstrated for special cases by calculating the total
electromagnetic momentum and energy. Since the ratio of momentum to energy is a
constant smaller than 1/c, there exists a Lorentz transformation to a frame in
which the total momentum is zero. In the zero-momentum frame the fields are
those of an annular pulse converging onto or diverging from a focal region.


title:
Lorentz Force Correction and Radiation Frequency Property of Charged
  Particles in Magnetic Dipole

abstract:
  By concern of compression of charge density field, the corrected Lorentz
force formula and consequent inference is presented. And further radiation
frequency property of an individual charge density field in magnetic dipole is
analyzed respectively for radiant property of the charged particle and the
emitted electromagnetic wave transfer property between the moving radiant
source and observer. As results, the behavior and radiation frequency property
of the electron beam in magnetic dipole is interpreted upon the individual's
behavior and property. At final, the potential application is put forward for
wider interest.


title:
Energy Differential Structure and Exchange of A Micro Flux Increment of
  Charged Particles in Longitudinal Acceleration

abstract:
  Differential energy structure of a micro multi-charged-particle system and
the beam internal potential energy is derived with consequent property and
ecessary inference. Then by combining the energy differential structure with
differential transfer relations of physical flux density between different time
domains, we present a general explicit formula for energy exchange in the beam
element's transfer or accelerating process between source and observer, further
give an analysis on relativistic beam's mass-energy relation and beam's energy
up limits for resonant frequency (rf) and DC acceleration. Finally we discuss
the property of elementary charge density field and consequences.


title:
Differential Transfer Relations of Physical Flux Density Between Time
  Domains of the Flux Source and Observer

abstract:
  Differential transfer relations of flux density, general physics quantities'
and its corresponding energy's, between time domains of source and observer are
derived from conservative rule of various physical quantities and time function
between the two domains. In addition, integrated form of the relations are
inferred and examples of potential application are illustrated and discussed.


title:
Phase Difference Function in Coherent Temporal-spatial Region and
  Unified Equations of Steady, Non-steady Interference

abstract:
  Phase difference function is established by means of phase transfer function
between time domains of source and interference point. The function reveals a
necessary interrelation between outcome of two-beam interference, source's
frequency and measured subject's kinematic information. As inference unified
equations on steady and non-steady interference are derived. Meanwhile relevant
property and application are discussed.


title: A compact, multi-pixel parametric light source

abstract:
  The features of a compact, single pass, multi-pixel optical parametric
generator are discussed. Several hundreds of independent high spatial-quality
tunable ultrashort pulses were produced by pumping a bulk lithium triborate
crystal with an array of tightly focussed intense beams. The array of beams was
produced by shining a microlenses array with a large pump beam. Overall
conversion efficiency to signal and idler up to 30% of the pump beam has been
reported. Shot-to-shot energy fluctuation down to 3% was achieved for the
generated radiation.


title: Quantum four-body system in D dimensions

abstract:
  By the method of generalized spherical harmonic polynomials, the
Schr\"{o}dinger equation for a four-body system in $D$-dimensional space is
reduced to the generalized radial equations where only six internal variables
are involved. The problem on separating the rotational degrees of freedom from
the internal ones for a quantum $N$-body system in $D$ dimensions is generally
discussed.


title: Optimal representations of quantum states by gaussians in phase space

abstract:
  A two-step optimization is proposed to represent an arbitrary quantum state
to a desired accuracy with the least number of gaussians in phase space. The
Husimi distribution of the quantum state provides the information to determine
the modulus of the weight for the gaussians. Then, the phase information
contained in the Wigner distribution is used to obtain the full complex weights
by considering the relative phases for pairs of gaussians, the chords. The
method is exemplified with several excited states n of the harmonic and the
Morse oscillators. A semiclassical interpretation of the number of gaussians
needed as a function of the quantum number n is given. The representation can
also be used to characterize Wigner and Husimi distributions directly which do
not originate in a quantum state.


title:
Red solitons: evidence of spatio--temporal instability in $\chi^{(2)}$
  spatial-soliton dynamics

abstract:
  In $\chi^{(2)}$ three-wave mixing, the noise-seeded spatio--temporal
modulational instability has a dramatic impact on the spatial-soliton dynamics,
leading to the counterintuitive observation of a soliton with no apparent
participation of the high-frequency field in the process.


title: Forbidden Transitions in a Magneto-Optical Trap

abstract:
  We report the first observation of a non-dipole transition in an ultra-cold
atomic vapor. We excite the 3P-4P electric quadrupole (E2) transition in
$^{23}$Na confined in a Magneto-Optical Trap(MOT), and demonstrate its
application to high-resolution spectroscopy by making the first measurement of
the hyperfine structure of the 4P$_{1/2}$ level and extracting the magnetic
dipole constant A $=$ 30.6 $\pm$ 0.1 MHz. We use cw OODR (Optical-Optical
Double Resonance) accompanied by photoinization to probe the transition.


title: Molecular Mechanism for Nitrogen fixation: first steps

abstract:
  N2 association to the FeMo-cofactor of nitrogenase, including the recently
identified central N ligand, has been investigated using first-principles
electronic structure calculations. The oxidation state of the resting state of
the cofactor and its electronic structure has been identified. A single proton
is added to the sulfur bridges following each electron transfer to the
cofactor. During N2 association, the cofactor undergoes large rearrangements
resulting in opening the central Fe-cage of the cofactor. N2 binds axially
while the bond of the bridging SH group breaks. It is then able to insert
between the two Fe sites in a bridged configuration.


title:
Transverse self-interactions within an electron bunch moving in an arc
  of a circle (generalized)

abstract:
  Transverse self-interactions within a "line" bunch of electrons moving in an
arc of a circle have been studied extensively by us from an electrodynamical
viewpoint. Here we treat an electron bunch with a given vertical (i.e.
perpendicular to the orbital plane) size by a generalization of our previous
work to the case of a test particle with vertical displacement interacting with
a line bunch. In fact, since a bunch with vertical extent can always be thought
of as a superposition of displaced charge lines, all the relevant physical
aspects of the problem are included in the study of that simple model. Our
generalization results in a physically meaningful and quantitative explanation
of the simulations obtained with the code $TraFiC^4$ as well as in successful
cross-checking of the code.


title:
Analytical Approach to Fast (e,3e) Double Ionization of Molecular
  Hydrogen

abstract: unpublished; this paper has been withdrawn.


title: A model for rapid stochastic distortions of small-scale turbulence

abstract:
  We present a model describing evolution of the small-scale Navier-Stokes
turbulence due to its stochastic distortions by much larger turbulent scales.
This study is motivated by numerical findings (laval, 2001) that such
interactions of separated scales play important role in turbulence
intermittency. We introduce description of turbulence in terms of the moments
of the k-space quantities using a method previously developed for the kinematic
dynamo problem (Nazarenko, 2003). Working with the $k$-space moments allows to
introduce new useful measures of intermittency such as the mean polarization
and the spectral flatness. Our study of the 2D turbulence shows that the energy
cascade is scale invariant and Gaussian whereas the enstrophy cascade is
intermittent. In 3D, we show that the statistics of turbulence wavepackets
deviates from gaussianity toward dominance of the plane polarizations. Such
turbulence is formed by ellipsoids in the $k$-space centered at its origin and
having one large, one neutral and one small axes with the velocity field
pointing parallel to the smallest axis.


title: Random Walk with Shrinking Steps

abstract:
  We outline basic properties of a symmetric random walk in one dimension, in
which the length of the nth step equals lambda^n, with lambda<1. As the number
of steps N-->oo, the probability that the endpoint is at x, P_{lambda}(x;N),
approaches a limiting distribution P_{lambda}(x) that has many beautiful
features. For lambda<1/2, the support of P_{lambda}(x) is a Cantor set. For
1/2<=lambda<1, there is a countably infinite set of lambda values for which
P_{lambda}(x) is singular, while P_{lambda}(x) is smooth for almost all other
lambda values. In the most interesting case of lambda=(sqrt{5}-1)/2=g, P_g(x)
is riddled with singularities and is strikingly self-similar. The
self-similarity is exploited to derive a simple form for the probability
measure M(a,b)= int_a^b P_g(x) dx.

categories: physics.ed-ph cond-mat.stat-mech math.PR physics.gen-ph


title: Scattering of the acoustic waves on finite cylindrical covers

abstract:
  In this work we developed a new problem solution methodology of contact
interaction of acoustic medium with resilient finite bodies of cylindrical
form, based on application of boundary integral equations method in conjunction
with series method with later use of series convergence improvement taking into
account the particularities of the determined functions.


title: Quelques reflexions sur la conception du monde de Erwin Schrodinger

abstract:
  Some personal reflections are made about the philosophical posture of Erwin
Schrodinger, as exposed in one of his book "Ma Conception du Monde". It is
argued that the Taoist view of the world, as pursued by Schrodinger, although
characterized by the dialectical struggle between opposite truths does not
contain the temporal dimension, the unique which allows an evolving
understanding of phenomena and objects that compose this world in constant
evolution. In our point of view, only a genetic view - which is missing in the
actual scientific paradigm - will bring a more deep explanation and
understanding of Reality.


title: Observed photodetachment in parallel electric and magnetic fields

abstract:
  We investigate photodetachment from negative ions in a homogeneous 1.0-T
magnetic field and a parallel electric field of approximately 10 V/cm. A
theoretical model for detachment in combined fields is presented. Calculations
show that a field of 10 V/cm or more should considerably diminish the Landau
structure in the detachment cross section. The ions are produced and stored in
a Penning ion trap and illuminated by a single-mode dye laser. We present
preliminary results for detachment from S- showing qualitative agreement with
the model. Future directions of the work are also discussed.


title: Students' Understanding of Direct Current Resistive Electrical Circuits

abstract:
  Research has shown that both high school and university students' reasoning
patterns regarding direct current resistive electric circuits often differ from
the currently accepted explanations. At present, there are no standard
diagnostic examinations in electric circuits. Two versions of a diagnostic
instrument called Determining and Interpreting Resistive Electric circuits
Concepts Tests (DIRECT) were developed, each consisting of 29 questions. The
information provided by the exam provides classroom instructors a means with
which to evaluate the progress and conceptual difficulties of their students
and their instructional methods. It can be used to evaluate curricular packages
and/or other supplemental materials for their effectiveness in overcoming
students' conceptual difficulties. The analyses indicate that students,
especially females, tend to hold multiple misconceptions, even after
instruction. During interviews, the idea that the battery is a constant source
of current was used most often in answering the questions. Students tended to
focus on current in solving the problems and to confuse terms, often assigning
the properties of current to voltage and/or resistance. Results indicated that
students do not have a clear understanding of the underlying mechanisms of
electric circuit phenomena. On the other hand, students were able to translate
easily from a "realistic" representation of a circuit to the corresponding
schematic diagram.


title:
Message Passing Fluids: molecules as processes in parallel computational
  fluids

abstract:
  In this paper we present the concept of MPF, Message Passing Fluid, an
abstract fluid where the molecules move by mean of the informations that they
exchange each other, on the basis of rules and methods of a generalized
Cellular Automaton. The model is intended for its simulation by mean of message
passing libraries on the field of parallel computing. We present a critical
analysis of the necessary computational effort in a possible implementation of
such an object.


title: Asymptotic properties of self-energy coefficients

abstract:
  We investigate the asymptotic properties of higher-order binding corrections
to the one-loop self-energy of excited states in atomic hydrogen. We evaluate
the historically problematic A60 coefficient for all P states with principal
quantum numbers n <= 7 and D states with n <= 8 and find that a satisfactory
representation of the n-dependence of the coefficients requires a
three-parameter fit. For the high-energy contribution to A60, we find exact
formulas. The results obtained are relevant for the interpretation of
high-precision laser spectrocopic measurements.


title:
Energy minimization using Sobolev gradients: application to phase
  separation and ordering

abstract:
  A common problem in physics and engineering is the calculation of the minima
of energy functionals. The theory of Sobolev gradients provides an efficient
method for seeking the critical points of such a functional. We apply the
method to functionals describing coarse-grained Ginzburg-Landau models commonly
used in pattern formation and ordering processes.


title: A model differential equation for turbulence

abstract:
  A phenomenological turbulence model in which the energy spectrum obeys a
nonlinear diffusion equation is presented. This equation respects the scaling
properties of the original Navier-Stokes equations and it has the Kolmogorov
-5/3 cascade and the thermodynamic equilibrium spectra as exact steady state
solutions. The general steady state in this model contains a nonlinear mixture
of the constant-flux and thermodynamic components. Such "warm cascade"
solutions describe the bottleneck phenomenon of spectrum stagnation near the
dissipative scale. Self-similar solutions describing a finite-time formation of
steady cascades are analysed and found to exhibit nontrivial scaling behaviour.


title:
Light transport in cold atoms: the fate of coherent backscattering in
  the weak localization regime

abstract:
  The recent observation of coherent backscattering (CBS) of light by atoms has
emphasized the key role of the velocity spread and of the quantum internal
structure of the atoms. Firstly, using highly resonant scatterers imposes very
low temperatures of the disordered medium in order to keep the full contrast of
the CBS interference. This criterion is usually achieved with standard laser
cooling techniques. Secondly, a non trivial internal atomic structure leads to
a dramatic decrease of the CBS contrast. Experiments with Rubidium atoms (with
a non trivial internal structure) and with Strontium (with the simplest
possible internal structure) show this behaviour and confirm theoretical
calculations.


title: Experimental observation of fractal modes in unstable optical resonators

abstract:
  We use a spatially resolved cavity ring-down technique to show that the 2D
eigenmode of an unstable optical cavity has a fractal pattern, i.e. it looks
the same at different length scales. In agreement with theory, we find that
this pattern has the maximum conceivable roughness, i.e., its fractal dimension
is 3.01 plus\minus 0.04. This insight in the nature of unstable cavity
eigenmodes may lead to better understanding of wave dynamics in open systems,
for both light and matter waves.


title: Fundamental and vortex solitons in a two-dimensional optical lattice

abstract:
  Fundamental and vortex solitons in a two-dimensional optically induced
waveguide array are reported. In the strong localization regime, the
fundamental soliton is largely confined to one lattice site, while the vortex
state comprises of four fundamental modes superimposed in a square
configuration with a phase structure that is topologically equivalent to the
conventional vortex. However, in the weak localization regime, both the
fundamental and vortex solitons spread over many lattice sites. We further show
that fundamental and vortex solitons are stable against small perturbations in
the strong localization regime.


title: The ^3He^4He_2$ trimer within the hard-core Faddeev approach

abstract:
  We apply a hard-core version of the Faddeev differential equations to the
^3He^4He_2 three-atomic system. Employing the TTY interatomic potential by
Tang, Toennies and Yiu we calculate the binding energy of the ^3He^4He_2 trimer
and the scattering length of a ^3He atom off a ^4He dimer.


title:
New recursion relations of matrix elements of $r^\lambda$ and $\beta
  r^\lambda$ between relativistic hydrogenic eigenstates

abstract:
  We determine exact recurrence relations which help in the evaluation of
matrix elements of powers of the radial coordinate between Dirac relativistic
hydrogenic eigenstates. The power $\lambda$ can be any complex number as long
as the corresponding term vanishes faster than $r^{-1}$ as $r \to \infty$.
These formulas allow determining recursively any matrix element of radial
powers --$r^\lambda$ or $\beta r^\lambda$, $\beta$ is a Dirac matrix-- in terms
of the two previous consecutive elements. The results are useful in
relativistic atomic calculations.


title:
Universal behavior of localization of residue fluctuations in globular
  proteins

abstract:
  Localization properties of residue fluctuations in globular proteins are
studied theoretically by using the Gaussian network model. Participation ratio
for each residue fluctuation mode is calculated. It is found that the
relationship between participation ratio and frequency is similar for all
globular proteins, indicating a universal behavior in spite of their different
size, shape, and architecture.


title: Comment on "Phase Transition-Like Behavior in a Low-Pass Filter"

abstract:
  This is a reminder that an infinite series can be defined other than as the
limit of a sequence of finite series. An example is provided in which a circuit
element comprised of an infinite series of resistors has negative resistance.


title:
Three-body recombination at large scattering lengths in an ultracold
  atomic gas

abstract:
  We study three-body recombination in an optically trapped ultracold gas of
cesium atoms with precise magnetic control of the s-wave scattering length a.
At large positive values of a, we measure the dependence of the rate
coefficient on a and confirm the theoretically predicted scaling proportional
to a^4. Evidence of recombination heating indicates the formation of very
weakly bound molecules in the last bound energy level.


title:
Cosmological Natural Selection Revisited. Some Remarks on the Conceptual
  Conundrum and Possible Alleys

abstract:
  Following the selection metaphor as introduced by Lee Smolin in his 1997 book
with respect to a possible model of the reproduction of Universes, this model
is being reconstructed utilizing the strict analogical form of the metaphor
chosen. It is asked then for the genotypal level associated with the primarily
phenotypal model, and it is asked in particular where the information
processing mechanism of that cosmological sort of selection could actually be
found. It is argued that massive black holes in the centres of galaxies may
play this important role. Some consequences on black holes in general are
discussed then pointing to the necessity to actually revisit the concepts of
virtual and actual black holes also.


title:
Long-range Static Directional Stress Transfer in a Cracked, Nonlinear
  Elastic Crust

abstract:
  Seeing the Earth crust as crisscrossed by faults filled with fluid at close
to lithostatic pressures, we develop a model in which its elastic modulii are
different in net tension versus compression. In constrast with standard
nonlinear effects, this ``threshold nonlinearity'' is non-perturbative and
occurs for infinitesimal perturbations around the lithostatic pressure taken as
the reference. For a given earthquake source, such nonlinear elasticity is
shown to (i) rotate, widen or narrow the different lobes of stress transfer,
(ii) to modify the $1/r^2$ 2D-decay of elastic stress Green functions into the
generalized power law $1/r^{\gamma}$ where $\gamma$ depends on the azimuth and
on the amplitude of the modulii asymmetry. Using reasonable estimates, this
implies an enhancement of the range of interaction between earthquakes by a
factor up to 5-10 at distances of several tens of rupture length. This may
explain certain long-range earthquake triggering and hydrological anomalies in
wells and suggest to revisit the standard stress transfer calculations which
use linear elasticity. We also show that the standard double-couple of forces
representing an earthquake source leads to an opening of the corresponding
fault plane, which suggests a mechanism for the non-zero isotropic component of
the seismic moment tensor observed for some events.


title:
The electron capture cross section using the r-CTMC method: a review and
  a suggestion for improvement

abstract:
  In this work we review the classical recipe for estimating partial cross
sections for electron capture into selected energy levels within the Classical
Trajectory Monte Carlo (CTMC) method [R.L. Becker and A.D. MacKellar, J. Phys.
B: At. Mol. Phys. 17 (1984) 3923], and point to a deficiency of the method when
applied to the CTMC in its r-version, according to the terminology introduced
by Cohen [J.S. Cohen, J. Phys. B: At. Mol. Phys. 18 (1985) 1759]. We suggest,
in this case, an alternative recipe based on the generation of stationary
classical spatial distributions for electrons in arbitrary levels. The output
of the CTMC simulations is projected onto these classical distributions rather
than on the quantal ones. A comparison between the two approaches is done.


title: Born renormalization in classical Maxwell electrodynamics

abstract:
  We define and compute the renormalized four-momentum of the composed physical
system: classical Maxwell field interacting with charged point particles. As a
`reference' configuration for the field surrounding the particle, we take the
Born solution. Unlike in the previous approach [Gen. Relat. Grav. 26 (1994)
167; Acta Phys. Pol. A 85 (1994) 771; Commun. Math. Phys. 198 (1998), 711],
based on the Coulomb `reference', a dependence of the four-momentum of the
particle (`dressed' with the Born solution) upon its acceleration arises in a
natural way. This will change the resulting equations of motion. Similarly, we
treat the angular momentum tensor of the system.


title:
Dynamical ionization ignition of clusters in intense and short laser
  pulses

abstract:
  The electron dynamics of rare gas clusters in laser fields is investigated
quantum mechanically by means of time-dependent density functional theory. The
mechanism of early inner and outer ionization is revealed. The formation of an
electron wave packet inside the cluster shortly after the first removal of a
small amount of electron density is observed. By collisions with the cluster
boundary the wave packet oscillation is driven into resonance with the laser
field, hence leading to higher absorption of laser energy. Inner ionization is
increased because the electric field of the bouncing electron wave packet adds
up constructively to the laser field. The fastest electrons in the wave packet
escape from the cluster as a whole so that outer ionization is increased as
well.


title:
Compositional analyses of a Reutlingen Bronze Age sword discovered at
  Giurgiu, Romania

abstract:
  The compositional scheme of a Bronze Age sword, found near the town of
Giurgiu in Romania has been determined by the method of particle-induced X-ray
emission (PIXE), at the tandem accelerator of the National Institute for
Physics and Nuclear Engineering from Bucharest, Magurele, Romania. The results
of the analyses and the comparison with the composition of other swords from
the same geographic area, the Danubian plane from Bulgaria and Transylvania
regions, show that the sword from Giurgiu could be relatively associated with
the swords from Bulgaria, having also the same stylistic, temporal and
geographical similitude.


title:
Evaluation of the two-photon exchange diagrams for the $(1s)^2 2p_{3/2}$
  electron configuration in Li-like ions

abstract:
  We present ab initio calculations of the complete gauge-invariant set of
two-photon exchange graphs for the $(1s)^2 2p_{3/2}$ electron configuration in
Li-like ions. These calculations are an important step towards the precise
theoretical determination of the $2p_{3/2}$-$2s$ transition energy in the
framework of QED.


title:
Absolute palaeointensity of Oligocene (28-30 Ma) lava flows from the
  Kerguelen Archipelago (southern Indian Ocean)

abstract:
  We report palaeointensity estimates obtained from three Oligocene volcanic
sections from the Kerguelen Archipelago (Mont des Ruches, Mont des Tempetes,
and Mont Rabouillere). Of 402 available samples, 102 were suitable for a
palaeofield strength determination after a preliminary selection, among which
49 provide a reliable estimate. Application of strict a posteriori criteria
make us confident about the quality of the 12 new mean-flow determinations,
which are the first reliable data available for the Kerguelen Archipelago. The
Virtual Dipole Moments (VDM) calculated for these flows vary from 2.78 to 9.47
10e22 Am2 with an arithmetic mean value of 6.15+-2.1 10e22 Am2. Compilation of
these results with a selection of the 2002 updated IAGA palaeointensity
database lead to a higher (5.4+-2.3 10e22 Am2) Oligocene mean VDM than
previously reported, identical to the 5.5+-2.4 10e22 Am2 mean VDM obtained for
the 0.3-5 Ma time window. However, these Kerguelen palaeointensity estimates
represent half of the reliable Oligocene determinations and thus a bias toward
higher values. Nonetheless, the new estimates reported here strengthen the
conclusion that the recent geomagnetic field strength is anomalously high
compared to that older than 0.3 Ma.


title:
Mono Lake or Laschamp geomagnetic event recorded from lava flows in
  Amsterdam Island (southeastern Indian Ocean)

abstract:
  We report a survey carried out on basalt flows from Amsterdam Island in order
to check the presence of intermediate directions interpreted to belong to a
geomagnetic field excursion within the Brunhes epoch, completing this
paleomagnetic record with paleointensity determinations and radiometric dating.
The directional results corroborate the findings by Watkins and Nougier (1973)
: normal polarity is found for two units and an intermediate direction, with
associated VGPs close to the equator, for the other two units. A notable result
is that these volcanic rocks are well suited for absolute paleointensity
determinations. Fifty percent of the samples yields reliable intensity values
with high quality factors. An original element of this study is that we made
use of the PTRM-tail test of Shcherbakova et al. (2000) to help in the
interpretation of the paleointensity measurements. Doing thus, only the high
temperature intervals, beyond 400 degres C, were retained to obtain the most
reliable estimate of the strength of the ancient magnetic field. The normal
units yield Virtual Dipole Moments (VDM) of 6.2 and 7.7 10e22 Am2 and the
excursional units yield values of 3.7 and 3.4 10e22 Am2. These results are
quite consistent with the other Thellier determinations from Brunhes excursion
records, all characterized by a decrease of the VDM as VGP latitude decreases.
40Ar/39Ar isotopic age determinations provide an estimate of 26+-15 Kyr and
18+-9 Kyr for the transitional lava flows, which could correspond to the Mono
Lake excursion. However, the large error bars associated with these ages do not
exclude the hypothesis that this event is the Laschamp.


title:
Stability of Negative Image Equilibria in Spike-Timing Dependent
  Plasticity

abstract:
  We investigate the stability of negative image equilibria in mean synaptic
weight dynamics governed by spike-timing dependent plasticity (STDP). The
neural architecture of the model is based on the electrosensory lateral line
lobe (ELL) of mormyrid electric fish, which forms a negative image of the
reafferent signal from the fish's own electric discharge to optimize detection
of external electric fields. We derive a necessary and sufficient condition for
stability, for arbitrary postsynaptic potential functions and arbitrary
learning rules. We then apply the general result to several examples of
biological interest.


title: Linear theory of nonlocal transport in a magnetized plasma

abstract:
  A system of nonlocal electron-transport equations for small perturbations in
a magnetized plasma is derived using the systematic closure procedure of V. Yu.
Bychenkov et al., Phys. Rev. Lett. 75, 4405 (1995). Solution to the linearized
kinetic equation with a Landau collision operator is obtained in the diffusive
approximation. The Fourier components of the longitudinal, oblique, and
transversal electron fluxes are found in an explicit form for quasistatic
conditions in terms of the generalized forces: the gradients of density and
temperature, and the electric field. The full set of nonlocal transport
coefficients is given and discussed. Nonlocality of transport enhances electron
fluxes across magnetic field above the values given by strongly collisional
local theory. Dispersion and damping of magnetohydrodynamic waves in weakly
collisional plasmas is discussed. Nonlocal transport theory is applied to the
problem of temperature relaxation across the magnetic field in a laser hot
spot.


title:
Equal energy sharing double photo ionization of the Helium atom at 20eV
  and 40eV above threshold

abstract:
  In this article we present triple differential cross sections for equal
energy sharing kinematics for double photoionization of the helium atom at 20
and 40eV above threshold in the framework of the hyperspherical partial wave
theory. This supplements our earlier work \cite{DCP03} in which we were
successful in showing fully, gauge independence of the results in our
formalism. Also in this work we treat cases in which the Stokes parameter S$_1
< 1$ so that partial polarization of the photon source is also taken into
account. Agreement in shape with the Convergent Close Coupling \cite{BK03,HB98}
calculation and the experiments appears to be excellent.


title: Thermal Study of the X+YCl (X, Y=H, D) Reactions

abstract:
  Time-dependent wave packet calculations for the reaction H+HCl and its
isotopic reactions are carried out on the potential energy surface (PES) of
Bian and Werner (BW2) [Bian, W.; Werner, H. -J., J. Chem. Phys. 2000, 112,
220]. Reaction probabilities for the exchanged and abstraction channels are
calculated from various initial rotational states of the reagent. Those have
then been used to estimate reaction cross sections and rate constants which
also are calculated and explained by the zero-point energy and the tunneling
effect. The results of this work were compared with that of previous
quasiclassical trajectory calculations and reaction dynamics experiments on the
abstraction channel. In addition, the calculated rate constants are in
reasonably good agreement with experimental measurements for both channels. Key
words: ab initio, H/D+ DCl/HCl, collision energy, integral cross section, rate
constan


title:
RF depolarizing resonances in the presence of a full Siberian snake and
  full snake spin-flipping

abstract:
  Frequent polarization reversals, or spin-flips, of a stored polarized beam in
a high energy scattering asymmetry experiments may greatly reduce systematic
errors of spin asymmetry measurements. A spin-flipping technique is being
developed by using rf magnets running at a frequency close to the spin
precession frequency, thereby creating spin-depolarizing resonances; the spin
can then be flipped by ramping the rf magnet's frequency through the resonance.
We studied, at the Indiana University Cyclotron Facility Cooler Ring,
properties of such rf depolarizing resonances in the presence of a nearly-full
Siberian snake and their possible application for spin-flipping. By using an
rf-solenoid magnet, we reached a 98.7% efficiency of spin-flipping. However, an
rf-dipole magnet is more practical at high energies; hence, studies of
spin-flipping by an rf-dipole are underway at IUCF.


title:
Quantum Statistics: Is there an effective fermion repulsion or boson
  attraction?

abstract:
  Physicists often claim that there is an effective repulsion between fermions,
implied by the Pauli principle, and a corresponding effective attraction
between bosons. We examine the origins of such exchange force ideas, the
validity for them, and the areas where they are highly misleading. We propose
that future explanations of quantum statistics should avoid the idea of a
effective force completely and replace it with more appropriate physical
insights, some of which are suggested here.


title: Perturbation Approach to the Self Energy of non-S Hydrogenic States

abstract:
  We present results on the self-energy correction to the energy levels of
hydrogen and hydrogenlike ions. The self energy represents the largest QED
correction to the relativistic (Dirac-Coulomb) energy of a bound electron. We
focus on the perturbation expansion of the self energy of non-S states, and
provide estimates of the so-called A60 perturbative coefficient, which can be
considered as a relativistic Bethe logarithm. Precise values of A60 are given
for many P, D, F and G states, while estimates are given for other electronic
states. These results can be used in high-precision spectroscopy experiments in
hydrogen and hydrogenlike ions. They yield the best available estimate of the
self-energy correction of many atomic states.


title: Using Drag to Hover

abstract:
  Unlike a helicopter, an insect can, in theory, use both lift and drag to stay
aloft. Here we show that a dragonfly uses mostly drag to hover by employing
asymmetric up and down strokes. Computations of a family of strokes further
show that using drag can be as efficient as using lift at the low Reynolds
number regime appropriate for insects.


title: Advanced Power Transmission of the Future

abstract:
  Electric power is a vital ingredient of modern society. This article is
written to provide an insight into the physics and engineering that go into the
transmission of electric power and its potential modernization. Topics covered
will be Transmission and Distribution, Comparing Overhead and Underground
Delivery, Pros and Cons of Underground Delivery, Superconducting Transmission,
Cryorisistive Delivery, Hyperconductivity, and Metal-Plated Graphite Fibers.


title: Recurrence relations for relativistic two centre matrix elements

abstract:
  Recursion formulae are derived for the calculation of two centre matrix
elements of a radial function in relativistic quantum mechanics. The recursions
are obtained between not necessarily diagonal radial eigensates using arbitrary
radial potentials and any radial functions. The only restriction is that the
potentials have to share a common minimum. Among other things, the relations so
obtained can help in evaluating relativistic corrections to transition
probabilities between atomic Rydberg states.


title:
Commutation of lightning impulse by multiarc erosive radial-slotted
  discharge

abstract:
  The non-stationary mode of radial-slotted erosive discharge was considered.
The existence condition of the relatively steady multiarc regime has been
found. Experimentally it has been shown that this discharge has been
corresponding to the required condition at the sufficiently large current. The
oscillograms of commutation of lightning impulse on the simulative test
facility with the equivalent of a high-voltage transmission line are presented.
The obtained results indicate the ability of erosive discharge, when using
within the framework of the complex lightning protection facility, to fast
commutation of lightning impulses at the level of rated current


title: Microcanonical Thermodynamic Properties of Helium Nanodroplets

abstract:
  The density of states and other thermodynamic functions of helium
nanodroplets are calculated for a microcanonical ensemble with both energy and
total angular momentum treated as conserved quantum numbers. These functions
allow angular momentum conserving evaporative cooling simulations.
  As part of this project, a recursion relationship is derived for the
reduction to irreducible representations of the n'th symmetric power of the
irreducible representations of the rotation group. These give the distribution
of total angular momentum states generated by putting multiple quanta into a
ripplon or phonon mode of the droplet, each of which is characterized by a
angular momentum quantum number.


title: The Euler-Lagrange Cohomology Groups on Symplectic Manifolds

abstract:
  The definition and properties of the Euler-Lagrange cohomology groups
$H^{2k-1}$, $1 \leqslant k \leqslant n$, on a symplectic manifold $({\cal
M}^{2n},\omega)$ are given and studied. For $k = 1$ and $k = n$, they are
isomorphic to the corresponding de Rham cohomology groups $H_{dR}^1({\cal
M}^{2n})$ and $H_{dR}^{2n-1}({\cal M}^{2n})$, respectively. The other
Euler-Lagrange cohomology groups are different from either the de Rham
cohomology groups or the harmonic cohomology groups on $({\cal
M}^{2n},\omega)$, in general. The general volume-preserving equations on
$({\cal M}^{2n},\omega)$ are also presented from cohomological point of view.
In the special cases, these equations become the ordinary canonical equations
in the Hamilton mechanics. Therefore, the Hamilton mechanics has been
generalized via the cohomology.


title:
Analysis of the intraspinal calcium dynamics and its implications on the
  plasticity of spiking neurons

abstract:
  The influx of calcium ions into the dendritic spines through the
N-metyl-D-aspartate (NMDA) channels is believed to be the primary trigger for
various forms of synaptic plasticity. In this paper, the authors calculate
analytically the mean values of the calcium transients elicited by a spiking
neuron undergoing a simple model of ionic currents and back-propagating action
potentials. The relative variability of these transients, due to the stochastic
nature of synaptic transmission, is further considered using a simple Markov
model of NMDA receptos. One finds that both the mean value and the variability
depend on the timing between pre- and postsynaptic action-potentials. These
results could have implications on the expected form of synaptic-plasticity
curve and can form a basis for a unified theory of spike time-dependent, and
rate based plasticity.


title: Non-stationary Spectra of Local Wave Turbulence

abstract:
  The evolution of the Kolmogorov-Zakharov (K-Z) spectrum of weak turbulence is
studied in the limit of strongly local interactions where the usual kinetic
equation, describing the time evolution of the spectral wave-action density,
can be approximated by a PDE. If the wave action is initially compactly
supported in frequency space, it is then redistributed by resonant interactions
producing the usual direct and inverse cascades, leading to the formation of
the K-Z spectra. The emphasis here is on the direct cascade. The evolution
proceeds by the formation of a self-similar front which propagates to the right
leaving a quasi-stationary state in its wake. This front is sharp in the sense
that the solution remains compactly supported until it reaches infinity. If the
energy spectrum has infinite capacity, the front takes infinite time to reach
infinite frequency and leaves the K-Z spectrum in its wake. On the other hand,
if the energy spectrum has finite capacity, the front reaches infinity within a
finite time, t*, and the wake is steeper than the K-Z spectrum. For this case,
the K-Z spectrum is set up from the right after the front reaches infinity. The
slope of the solution in the wake can be related to the speed of propagation of
the front. It is shown that the anomalous slope in the finite capacity case
corresponds to the unique front speed which ensures that the front tip contains
a finite amount of energy as the connection to infinity is made. We also
introduce, for the first time, the notion of entropy production in wave
turbulence and show how it evolves as the system approaches the stationary K-Z
spectrum.


title: Dimensional Analysis and Weak Turbulence

abstract:
  In the study of weakly turbulent wave systems possessing incomplete
self-similarity it is possible to use dimensional arguments to derive the
scaling exponents of the Kolmogorov-Zakharov spectra, provided the order of the
resonant wave interactions responsible for nonlinear energy transfer is known.
Furthermore one can easily derive conditions for the breakdown of the weak
turbulence approximation. It is found that for incompletely self-similar
systems dominated by three wave interactions, the weak turbulence approximation
usually cannot break down at small scales. It follows that such systems cannot
exhibit small scale intermittency. For systems dominated by four wave
interactions, the incomplete self-similarity property implies that the scaling
of the interaction coefficient depends only on the physical dimension of the
system. These results are used to build a complete picture of the scaling
properties of the surface wave problem where both gravity and surface tension
play a role. We argue that, for large values of the energy flux, there should
be two weakly turbulent scaling regions matched together via a region of
strongly nonlinear turbulence.


title:
Role of the dielectric constant of ferroelectric ceramic in enhancing
  the ionic conductivity of a polymer electrolyte composite

abstract:
  The dispersal of high dielectric constant ferroelectric ceramic material
Ba(0.7)Sr(0.3)TiO(3) (Tc~30 C) and Ba(0.88)Sr(0.12)TiO(3) (Tc~90 C) in an ion
conducting polymer electrolyte (PEO:NH4I) is reported to result in an increase
in the room temperature ionic conductivity by two orders of magnitude. The
conductivity enhancememt "peaks" as we approach the dielectric phase transition
of the dispersed ferroelectric material where the dielectric constant changes
from ~ 2000 to 4000. This establishes the role of dielectric constant of the
dispersoid in enhancing the ionic conductivity of the polymeric composites.


title: Drift Lagrangian for relativistic particle in intense laser field

abstract:
  The Lagrangian and Hamiltonian functions describing average motion of a
relativistic particle under the action of a slightly inhomogeneous intense
laser field are obtained. In weak low-frequency background fields, such a
particle on average drifts with an effective, relativistically invariant mass,
which depends on the laser intensity. The essence of the proposed ponderomotive
formulation is presented in a physically intuitive and mathematically simple
form, yet represents a powerful tool for studying various nonlinear phenomena
caused by interaction of currently available smooth ultra-intense laser pulses
with plasmas.


title:
Forced Stratified Turbulence: Successive Transitions with Reynolds
  Number

abstract:
  Numerical simulations are made for forced turbulence at a sequence of
increasing values of Reynolds number, R, keeping fixed a strongly stable,
volume-mean density stratification. At smaller values of R, the turbulent
velocity is mainly horizontal, and the momentum balance is approximately
cyclostrophic and hydrostatic. This is a regime dominated by so-called pancake
vortices, with only a weak excitation of internal gravity waves and large
values of the local Richardson number, Ri, everywhere. At higher values of R
there are successive transitions to (a) overturning motions with local
reversals in the density stratification and small or negative values of Ri; (b)
growth of a horizontally uniform vertical shear flow component; and (c) growth
of a large-scale vertical flow component. Throughout these transitions, pancake
vortices continue to dominate the large-scale part of the turbulence, and the
gravity wave component remains weak except at small scales.


title: Efimov states in asymmetric systems

abstract:
  The conditions for occurrence of the Efimov effect is briefly described using
hyperspherical coordinates. The strength of the effective hyperradial
$\rho^{-2}$ potential appearing for two or three large scattering lengths is
computed and discussed as function of two independent mass ratios of the three
constituent particles. The effect is by far most pronounced for asymmetric
systems with three very different masses. One Efimov state may by chance appear
in nuclei. Many states could be present for systems with one electron and two
neutral atoms or molecules. Estimates of the number of states and their sizes
and energies are given.


title: The mathematical features of the continuity equation

abstract:
  The conditions under which, the continuity equation can be substituted by an
ordinary non differential equation, will be discussed. Since continuity
equation is a fundamental equation, this result will be applicable in a vast
area of Physics.


title: Improved Power System of the Future

abstract:
  This paper is intended to provide an insight into physics and engineering
that can modernize electric power systems. Topics covered are Flexible ac
transmission systems (FACTS), Custom Power, Greatly improved Capacitors,
Electrical Insulation, Distribution Cables, Improved Polymeric Insulation,
Underground Vault Explosions, Fault Location, Smart Cables, Neutral and Ground,
Corrosion and Protection, Conventional Transformers, Compact Transformers,
Ferroresonance, and Solid State Transformers.


title:
Third-order relativistic many-body calculations of energies and
  lifetimes of levels along the silver isoelectronic sequence

abstract:
  Energies of 5l_j (l= s, p, d, f, g) and 4f_j states in neutral Ag and Ag-like
ions with nuclear charges Z = 48 - 100 are calculated using relativistic
many-body perturbation theory. Reduced matrix elements, oscillator strengths,
transition rates and lifetimes are calculated for the 17 possible 5l_j-5l'_{j'}
and 4f_j-5l_{j'} electric-dipole transitions. Third-order corrections to
energies and dipole matrix elements are included for neutral Ag and for ions
with Z<61. Second-order corrections are included for Z>60. Comparisons are made
with available experimental data for transition energies and lifetimes.
Correlation energies and transition rates are shown graphically as functions of
nuclear charge Z for selected cases. These calculations provide a theoretical
benchmark for comparison with experiment and theory.


title:
The Proof that the Standard Transformations of E and B are not the
  Lorentz Transformations. Clifford Algebra Formalism

abstract:
  In this paper it is exactly proved by using the Clifford algebra formalism
that the standard transformations of the three-dimensional (3D) vectors of the
electric and magnetic fields E and B are not the Lorentz transformations of
well-defined quantities from the 4D spacetime but the 'apparent'
transformations of the 3D quantities. Thence the usual Maxwell equations with
the 3D E and B are not in agreement with special relativity. The 1-vectors E
and B, as well-defined 4D quantities, are introduced instead of ill-defined 3D
E and B.


title: Global Stationary Phase and the Sign Problem

abstract:
  We present a computational strategy for reducing the sign problem in the
evaluation of high dimensional integrals with non-positive definite weights.
The method involves stochastic sampling with a positive semidefinite weight
that is adaptively and optimally determined during the course of a simulation.
The optimal criterion, which follows from a variational principle for analytic
actions S(z), is a global stationary phase condition that the average gradient
of the phase Im(S) along the sampling path vanishes. Numerical results are
presented from simulations of a model adapted from statistical field theories
of classical fluids.


title: A comment on the Invariance of the Speed of Light

abstract:
  The invariance of the speed of light in all inertial frames is shown to be an
inevitable consequence of the relativity principle of special relativity
contrary to the view held by Hsu and Hsu in taiji relativity where the speed of
light is no longer a universal constant. The present approach is not only new
but also much simpler than the existing approaches.


title:
Effect of different choices of the Boltzmannized flux operator on
  thermal exchange and recombination reactions

abstract:
  The rate constants for recombination and exchange reactions are calculated
using the flux correlation approach with a general form of the Boltzmannized
flux operator, which can simultaneously describe the Kubo and traditional
half-split forms. First, we consider an exactly solvable model, i.e., the free
particle case, in terms of a new scaling function. Next, as a non-trivial case,
we study the recombination and exchange reactions at very high pressure. Since
the rate constant is calculated by Laplace transform of the flux correlation
function, the result depends on how the Boltzmannized flux operator is chosen.
We find that a choice of the flux operator affects the rate constant
considerably. For the recombination reaction, the ratio of the rate constant in
the half-split form to that in the Kubo form approaches zero in the high
pressure limit.


title:
Long-range attraction between particles in dusty plasma and partial
  surface tension of dusty phase boundary

abstract:
  Effective potential of a charged dusty particle moving in homogeneous plasma
has a negative part that provides attraction between similarly charged dusty
particles. A depth of this potential well is great enough to ensure both
stability of crystal structure of dusty plasma and sizable value of surface
tension of a boundary surface of dusty region. The latter depends on the
orientation of the surface relative to the counter-ion flow, namely, it is
maximal and positive for the surface normal to the flow and minimal and
negative for the surface along the flow. For the most cases of dusty plasma in
a gas discharge, a value of the first of them is more than sufficient to ensure
stability of lenticular dusty phase void oriented across the counter-ion flow.


title: Induced-Charge Electro-Osmosis

abstract:
  We describe the general phenomenon of `induced-charge electro-osmosis' (ICEO)
-- the nonlinear electro-osmotic slip that occurs when an applied field acts on
the ionic charge it {\sl induces} around a polarizable surface. Motivated by a
simple physical picture, we calculate ICEO flows around conducting cylinders in
steady (DC), oscillatory (AC), and suddenly-applied electric fields. This
picture, and these systems, represent perhaps the clearest example of nonlinear
electrokinetic phenomena. We complement and verify this physically-motivated
approach using a matched asymptotic expansion to the electrokinetic equations
in the thin double-layer and low potential limits. ICEO slip velocities vary
like $u_s \propto E_0^2 L$, where $E_0$ is the field strength and $L$ is a
geometric length scale, and are set up on a time scale $\tau_c = \lambda_D
L/D$, where $\lambda_D$ is the screening length and $D$ is the ionic diffusion
constant. We propose and analyze ICEO microfluidic pumps and mixers that
operate without moving parts under low applied potentials. Similar flows around
metallic colloids with fixed total charge have been described in the Russian
literature (largely unnoticed in the West). ICEO flows around conductors with
fixed potential, on the other hand, have no colloidal analog and offer further
possibilities for microfluidic applications.


title:
Shell Model for Drag Reduction with Polymer Additive in Homogeneous
  Turbulence

abstract:
  Recent direct numerical simulations of the FENE-P model of non-Newtonian
hydrodynamics revealed that the phenomenon of drag reduction by polymer
additives exists (albeit in reduced form) also in homogeneous turbulence. We
introduce here a simple shell model for homogeneous viscoelastic flows that
recaptures the essential observations of the full simulations. The simplicity
of the shell model allows us to offer a transparent explanation of the main
observations. It is shown that the mechanism for drag reduction operates mainly
on the large scales. Understanding the mechanism allows us to predict how the
amount of drag reduction depends of the various parameters in the model. The
main conclusion is that drag reduction is not a universal phenomenon, it peaks
in a window of parameters like Reynolds number and the relaxation rate of the
polymer.


title: Spiral and Taylor vortex fronts and pulses in axial through-flow

abstract:
  The influence of an axial through-flow on the spatiotemporal growth behavior
of different vortex structures in the Taylor-Couette system with radius ratio
eta=0.5 is determined. The Navier Stokes equations (NSE) linearized around the
basic Couette-Poiseuille flow are solved numerically with a shooting method in
a wide range of through-flow strengths Re and different rates of co- and
counterrotating cylinders for toroidally closed vortices with azimuthal wave
number m=0 and for spiral vortex flow with m=+1 and m=-1. For each of these
three different vortex varieties we have investigated (i) axially extended
vortex structures, (ii) axially localized vortex pulses, and (iii) vortex
fronts. The complex dispersion relations of the linearized NSE for vortex modes
with the three different m are evaluated for real axial wave numbers for (i)
and over the plane of complex axial wave numbers for (ii,iii). We have also
determined the Ginzburg-Landau amplitude equation (GLE) approximation in order
to analyze its predictions for the vortex stuctures (ii,iii). Critical
bifurcation thresholds for extended vortex structures are evaluated. The
boundaries between absolute and convective instability of the basic state for
vortex pulses are determined with a saddle-point analysis of the dispersion
relations. Finally, the linearly selected front behavior of growing vortex
structures is investigated. For the two front intensity profiles (increasing in
positive or negative axial direction) we have determined front velocities,
axial growth rates, and the wave numbers and frequencies of the unfolding
vortex patterns with azimuthal wave numbers m=0, +1, -1, respectively.


title: The length of day in the past

abstract:
  We have found an empirical law for the variation of the length of the Earth's
day with geologic time employing Wells's data. We attribute the lengthening of
the Earth's day to the present cosmic expansion of the Universe. The prediction
of law has been found to be in agreement with the astronomical and geological
data. The day increases at a present rate of 0.002 sec/century. The length of
the day is found to be 6 hours when the Earth formed. We have also found a new
limit for the value of the Hubble constant and the age of the Universe.


title: High contrast optical modulation by surface acoustic waves

abstract:
  Numerical Calculations are employed to study the modulation of light by
surface acoustic waves (SAWs) in photonic band gap (PBG) structures. The on/off
contrast ratio in PBG switch based on optical cavity is determined as a
function of the SAW induced dielectric modulation. We show that these
structures exhibit high contrast ratios even for moderate acousto-optic
coupling


title: The size impact on evolutionary dynamics of agents-cluster

abstract:
  A cluster theory based mathematical model was developed and used to simulate
the dynamics of a system composed of a large number of interacting
agents-clusters with different size. The case of a system formed by a constant
total number of economic units (agents) in metastable (partial) equilibrium was
considered, and the size effect on the formation of the groups (clusters) of
agents was particularly elucidated. We prove that the fragmentation and
coagulation rates of groups of agents definitely depend on the size of the
group.


title:
Observation of diffractive orbits in the spectrum of excited NO in a
  magnetic field

abstract:
  We investigate the experimental spectra of excited NO molecules in the
diamagnetic regime and develop a quantitative semiclassical framework to
account for the results. We show the dynamics can be interpreted in terms of
classical orbits provided that in addition to the geometric orbits, diffractive
effects are appropriately taken into account. We also show how individual
orbits can be extracted from the experimental signal and use this procedure to
reveal the first experimental manifestation of inelastic diffractive orbits.


title: Microfabrication of Laser-Driven Accelerator Structures

abstract:
  We discuss the potential for using microfabrication techniques for
laser-driven accelerator construction. We introduce microfabrication processes
in general, and then describe our investigation of a particular trial process.
We conclude by considering the issues microfabrication raises for possible
future structures.


title: Power Delivery of the Future

abstract:
  This paper is written to provide an insight into the physics and engineering
that go into power delivery of the future. Topics covered are Fault Current
Limiters (FCL) including Superconducting FCL and Emission Limited FCL;
Lightning and Restoration Preparedness; Compressed-Gas-Insulated Delivery;
Evaporative Cooling Delivery; Advanced Delivery Technologies Requiring Big
Breakthroughs such as Conducting Polymers, Electron-Beam Delivery, Microwave
Delivery, and Laser-Beam Delivery.


title:
Quantum mechanics of Dirac particle beam transport through optical
  elements with straight and curved axes

abstract:
  Classical mechanical treatment of charged particle beam optics is so far very
satisfactory from a practical point of view in applications ranging from
electron microscopy to accelerator technology. However, it is desirable to
understand the underlying quantum mechanics since the classical treatment is
only an approximation. Quantum mechanical treatment of spin-1/2 particle beam
transport through optical elements with straight optic axes, based on the
proper equation, namely, the Dirac equation, has been developed already to some
extent. In such a theory the orbital and spin motions are treated within a
unified framework. Here, after a brief review of the Dirac spinor beam optics
for systems with straight optic axes it is outlined how the application of the
formalism of general relativity leads to the use of the Dirac equation for
getting a quantum theory of spin-1/2 beam transport through optical elements
with curved axes.


title: Quantum Vacuum Contribution to the Momentum of the Dielectric Media

abstract:
  Momentum transfer between matter and electromagnetic field is analyzed. The
related equations of motion and conservation laws are derived using
relativistic formalism. Their correspondence to various, at first sight
self-contradicting, experimental data (the so called Abraham-Minkowski
controversy) is demonstrated. A new, Casimir like, quantum phenomenon is
predicted: contribution of vacuum fluctuations to the motion of dielectric
liquids in crossed electric and magnetic fields. Velocities about $50nm/s$ can
be expected due to the contribution of high frequency vacuum modes.


title:
Variational principle for frozen-in vortex structures interacting with
  sound waves

abstract:
  General properties of conservative hydrodynamic-type models are treated from
positions of the canonical formalism adopted for liquid continuous media, with
applications to the compressible Eulerian hydrodynamics, special- and
general-relativistic fluid dynamics, and two-fluid plasma model including the
Hall-magnetohydrodynamics. A variational formulation is found for motion and
interaction of frozen-in localized vortex structures and acoustic waves in a
special description where dynamical variables are, besides the Eulerian fields
of the fluid density and the potential component of the canonical momentum,
also the shapes of frozen-in lines of the generalized vorticity. This
variational principle can serve as a basis for approximate dynamical models
with reduced number of degrees of freedom.


title:
Bayesian Inference in Processing Experimental Data: Principles and Basic
  Applications

abstract:
  This report introduces general ideas and some basic methods of the Bayesian
probability theory applied to physics measurements. Our aim is to make the
reader familiar, through examples rather than rigorous formalism, with concepts
such as: model comparison (including the automatic Ockham's Razor filter
provided by the Bayesian approach); parametric inference; quantification of the
uncertainty about the value of physical quantities, also taking into account
systematic effects; role of marginalization; posterior characterization;
predictive distributions; hierarchical modelling and hyperparameters; Gaussian
approximation of the posterior and recovery of conventional methods, especially
maximum likelihood and chi-square fits under well defined conditions; conjugate
priors, transformation invariance and maximum entropy motivated priors; Monte
Carlo estimates of expectation, including a short introduction to Markov Chain
Monte Carlo methods.


title:
Radiometric Determination of Uranium in Natural Waters after Enrichment
  and Separation by Cation-Exchange and Liquid-Liquid Extraction

abstract:
  The alpha-radiometric determination of uranium after its pre-concentration
from natural water samples using the cation-exchange resin Chelex-100, its
selective extraction by tributylphosphate and electrodeposition on stainless
steel discs is reported. The validity of the separation procedure and the
chemical recoveries were checked by addition of uranium standard solution as
well as by tracing with U-232. The average uranium yield was determined to be
(97 +- 2) % for the cation-exchange, (95 +- 2) % for the liquid-liquid
extraction, and more than 99% for the electrodeposition. Employing
high-resolution alpha-spectroscopy, the measured activity of the U-238 and
U-234 radioisotopes was found to be of similar magnitude; i.e. ~7 mBq/L and ~35
mBq/L for ground- and seawater samples, respectively. The energy resolution
(FWHM) of the alpha-peaks was 22 keV, while the Minimum Detectable Activity
(MDA) was estimated to be 1 mBq/L (at the 95% confidence limit).


title:
Experimental Identification of the Kink Instability as a Poloidal Flux
  Amplification Mechanism for Coaxial Gun Spheromak Formation

abstract:
  The magnetohydrodynamic kink instability is observed and identified
experimentally as a poloidal flux amplification mechanism for coaxial gun
spheromak formation. Plasmas in this experiment fall into three distinct
regimes which depend on the peak gun current to magnetic flux ratio, with (I)
low values resulting in a straight plasma column with helical magnetic field,
(II) intermediate values leading to kinking of the column axis, and (III) high
values leading immediately to a detached plasma. Onset of column kinking agrees
quantitatively with the Kruskal-Shafranov limit, and the kink acts as a dynamo
which converts toroidal to poloidal flux. Regime II clearly leads to both
poloidal flux amplification and the development of a spheromak configuration.


title: Optical Communication Noise Rejection Using Correlated Photons

abstract:
  This paper describes a completely new way to perform noise rejection using a
two-photon sensitive detector and taking advantage of the properties of
correlated photons to improve an optical communications link in the presence of
uncorrelated noise. In particular, a detailed analysis is made of the case
where a classical link would be saturated by an intense background, such as
when a satellite is in front of the sun,and identifies a regime where the
quantum correlating system has superior performance.


title: Quantum signatures in laser-driven relativistic multiple-scattering

abstract:
  The dynamics of an electronic Dirac wave packet evolving under the influence
of an ultra-intense laser pulse and an ensemble of highly charged ions is
investigated numerically. Special emphasis is placed on the evolution of
quantum signatures from single to multiple scattering events. We quantify the
occurrence of quantum relativistic interference fringes in various situations
and stress their significance in multiple-particle systems, even in the
relativistic range of laser-matter interaction.


title: Generalised Modal Analysis with the Pad\'e-Laplace transform

abstract:
  We present the G-MAPLE (Generalised Modal Analysis from the Poles of the
Laplace Expansion) software that allows decomposing data depending on a single
parameter (such as time series data) into a set of exponential functions having
complex amplitudes and arguments. The novelty is that G-MAPLE determines the
unknown number of exponentials in the data along with the corresponding complex
amplitudes and arguments.


title:
Analytical description of finite size effects for RNA secondary
  structures

abstract:
  The ensemble of RNA secondary structures of uniform sequences is studied
analytically. We calculate the partition function for very long sequences and
discuss how the cross-over length, beyond which asymptotic scaling laws apply,
depends on thermodynamic parameters. For realistic choices of parameters this
length can be much longer than natural RNA molecules. This has to be taken into
account when applying asymptotic theory to interpret experiments or numerical
results.


title:
Non-Gaussian Statistics of the Soliton Timing Jitter due to Amplifier
  Noise

abstract:
  Based on the first-order perturbation theory of soliton, the Gordon-Haus
timing jitter induced by amplifier noise is found to be non-Gaussian
distributed. Compared with Gaussian distribution given by the linearized
perturbation theory, both frequency and timing jitter have larger tail
probability. The timing jitter has a larger discrepancy to Gaussian
distribution than that of frequency jitter.


title: Analytical solution for nonlinear Schrodinger vortex reconnection

abstract:
  Analysis of the nonlinear Schrodinger vortex reconnection is given in terms
of coordinate-time power series. The lowest order terms in these series
correspond to a solution of the linear Schrodinger equation and provide several
interesting properties of the reconnection process, in particular the
non-singular character of reconnections, the anti-parallel configuration of
vortex filaments and a square-root law of approach just before/after
reconnections. The complete infinite power series represents a fully nonlinear
analytical solution in a finite volume which includes the reconnection point,
and is valid for finite time provided the initial condition is an analytic
function. These series solutions are free from the periodicity artifacts and
discretization error of the direct computational approaches and they are easy
to analyze using a computer algebra program.


title: Large Scale Evolution of Premixed Flames

abstract:
  The influence of the small scale ``cellular'' structure of premixed flames on
their evolution at larger scales is investigated. A procedure of the space-time
averaging of the flow variables over flame cells is introduced. It is proved
that to the leading order in the flame front thickness, the form of dynamical
equations for the averaged gas velocity and pressure, as well as of jump
conditions for these quantities at the flame front, is the same as in the case
of a zero-thickness flame propagating in an ideal fluid at constant velocity
with respect to the fuel, equal to the adiabatic velocity of a plane flame
times a factor describing increase of the flame front length due to the local
front wrinkling. As an application, the large scale evolution of a flame in the
gravitational field is investigated. A weakly nonlinear non-stationary equation
for the averaged flame front position is derived. It is found that the leading
nonlinear gravitational effects stabilize the flame propagating in the
direction of the field. The resulting stationary flame configurations are
determined analytically.


title:
Comparison of quantum mechanical and classical trajectory calculations
  of cross sections for ion-atom impact ionization of negative - and positive
  -ions for heavy ion fusion applications

abstract:
  Stripping cross sections in nitrogen have been calculated using the classical
trajectory approximation and the Born approximation of quantum mechanics for
the outer shell electrons of 3.2GeV I$^{-}$ and Cs$^{+}$ ions. A large
difference in cross section, up to a factor of six, calculated in quantum
mechanics and classical mechanics, has been obtained. Because at such high
velocities the Born approximation is well validated, the classical trajectory
approach fails to correctly predict the stripping cross sections at high
energies for electron orbitals with low ionization potential.


title: Some Remarks about Variable Mass Systems

abstract:
  We comment about the general argument given to obtain the rocket equation as
it is exposed in standard textbooks. In our opinion, it can induce students to
a wrong answer when solving variable mass problems.


title:
Stability of Semi-Implicit and Iterative Centred-Implicit Time
  Discretizations for Various Equation Systems Used in NWP

abstract:
  The stability of classical semi-implicit scheme, and some more advanced
iterative schemes recently proposed for Numerical Weather Prediction (NWP)
purpose is examined. In all these schemes, the solution of the centred-implicit
non-linear equation is approached by an iterative fixed-point algorithm,
preconditioned by a simple, constant in time, linear operator. A general
methodology for assessing analytically the stability of these schemes on
canonical problems for a vertically unbounded atmosphere is presented. The
proposed method is valid for all the equation systems usually employed in NWP.
However, as in earlier studies, the method can be applied only in simplified
meteorological contexts, thus overestimating the actual stability that would
occur in more realistic meteorological contexts. The analysis is performed in
the spatially-continuous framework, hence allowing to eliminate the
spatial-discretisation or the boundary conditions as possible causes of the
fundamental instabilities linked to the time-scheme itself. The general method
is then shown concretely to apply to various time-discretisation schemes and
equation-systems (namely shallow-water, and fully compressible Euler
equations). Analytical results found in the literature are recovered from the
proposed method, and some original results are presented.


title:
Analysis of the contributions of three-body potentials in the equation
  of state of 4He

abstract:
  The effect of three-body interatomic contributions in the equation of state
of 4He are investigated. A recent two-body potential together with the Cohen
and Murrell (Chem. Phys. Lett. 260, 371 (1996)) three-body potential are
applied to describe bulk helium. The triple-dipole dispersion and exchange
energies are evaluated subjected only to statistical uncertainties. An
extension of the diffusion Monte Carlo method is applied in order to compute
very small energies differences. The results show how the three-body
contributions affects the ground-state energy, the equilibrium, melting and
freezing densities.


title: Power Systems of the Future

abstract:
  Electric power is a vital ingredient of modern society. This paper in
conjunction with previous papers was written to provide an insight into the
physics and engineering that go into electric power systems and their
modernization. Topics covered here are Direct Current; Superconducting
Generators; Energy Storage; Voltage Sags; Grid Stability, Power System Planning
and Operations; Biological Effects of Electromagnetic Fields; Dispersed
Generation; Information Superhighway Synergy; Distribution Automation;
Conclusion.


title: Modeling stochastic clonal interference

abstract:
  We study the competition between several advantageous mutants in an asexual
population (clonal interference) as a function of the time between the
appearance of the mutants, their selective advantages, and the rate of
deleterious mutations. We find that the overall probability of fixation (the
probability that at least one of the mutants becomes the ancestor of the entire
population) does not depend on the time interval between the appearance of
these mutants, and equals the probability that a genotype bearing all of these
mutations reaches fixation. This result holds also in the presence of
deleterious mutations, and for an arbitrary number of competing mutants. We
also show that if mutations interfere, an increase in the mean number of
fixation events is associated with a decrease in the expected fitness gain of
the population.