title: Very Compact Expressions for Amplitudes

abstract:
  A number theoretic algorithm is given for writing gauge theory amplitudes in
a compact manner. It is possible to write down all details of the complete $L$
loop amplitude with two integers, or a complex integer. However, a more
symmetric notation requires more integers, five or seven, depending on the type
of theory. It is possible that in the symmetric form (or in the non-symmetric
form) that a direct (or less direct) recursive algorithm or generating function
can be developed to compute these numbers at arbitrary loop order. The
existence of this function is implied by the recursive structure of loop
amplitudes and their analyticity, i.e. multi-particle poles; a function
requiring a finite number of computations such as a polynomial with derivable
coefficients is desired.


title:
An assessment of the resolution limitation due to radiation-damage in
  x-ray diffraction microscopy

abstract:
  X-ray diffraction microscopy (XDM) is a new form of x-ray imaging that is
being practiced at several third-generation synchrotron-radiation x-ray
facilities. Although only five years have elapsed since the technique was first
introduced, it has made rapid progress in demonstrating high-resolution
threedimensional imaging and promises few-nm resolution with much larger
samples than can be imaged in the transmission electron microscope. Both life-
and materials-science applications of XDM are intended, and it is expected that
the principal limitation to resolution will be radiation damage for life
science and the coherent power of available x-ray sources for material science.
In this paper we address the question of the role of radiation damage. We use a
statistical analysis based on the so-called "dose fractionation theorem" of
Hegerl and Hoppe to calculate the dose needed to make an image of a lifescience
sample by XDM with a given resolution. We conclude that the needed dose scales
with the inverse fourth power of the resolution and present experimental
evidence to support this finding. To determine the maximum tolerable dose we
have assembled a number of data taken from the literature plus some
measurements of our own which cover ranges of resolution that are not well
covered by reports in the literature. The tentative conclusion of this study is
that XDM should be able to image frozen-hydrated protein samples at a
resolution of about 10 nm with "Rose-criterion" image quality.


title:
Electron wave functions on $T^2$ in a static magnetic field of arbitrary
  direction

abstract:
  A basis set expansion is performed to find the eigenvalues and wave functions
for an electron on a toroidal surface $T^2$ subject to a constant magnetic
field in an arbitrary direction. The evolution of several low-lying states as a
function of field strength and field orientation is reported, and a procedure
to extend the results to include two-body Coulomb matrix elements on $T^2$ is
presented.


title:
Experimental verification of a one-parameter scaling law for the quantum
  and "classical" resonances of the atom-optics kicked rotor

abstract:
  We present experimental measurements of the mean energy in the vicinity of
the first and second quantum resonances of the atom optics kicked rotor for a
number of different experimental parameters. Our data is rescaled and compared
with the one parameter epsilon--classical scaling function developed to
describe the quantum resonance peaks. Additionally, experimental data is
presented for the ``classical'' resonance which occurs in the limit as the
kicking period goes to zero. This resonance is found to be analogous to the
quantum resonances, and a similar one-parameter classical scaling function is
derived, and found to match our experimental results. The width of the quantum
and classical resonance peaks is compared, and their Sub-Fourier nature
examined.


title: A 96-Channel FPGA-based Time-to-Digital Converter

abstract:
  We describe an FPGA-based, 96-channel, time-to-digital converter (TDC)
intended for use with the Central Outer Tracker (COT) in the CDF Experiment at
the Fermilab Tevatron. The COT system is digitized and read out by 315 TDC
cards, each serving 96 wires of the chamber. The TDC is physically configured
as a 9U VME card. The functionality is almost entirely programmed in firmware
in two Altera Stratix FPGA's. The special capabilities of this device are the
availability of 840 MHz LVDS inputs, multiple phase-locked clock modules, and
abundant memory. The TDC system operates with an input resolution of 1.2 ns.
Each input can accept up to 7 hits per collision. The time-to-digital
conversion is done by first sampling each of the 96 inputs in 1.2-ns bins and
filling a circular memory; the memory addresses of logical transitions (edges)
in the input data are then translated into the time of arrival and width of the
COT pulses. Memory pipelines with a depth of 5.5 $\mu$s allow deadtime-less
operation in the first-level trigger. The TDC VME interface allows a 64-bit
Chain Block Transfer of multiple boards in a crate with transfer-rates up to 47
Mbytes/sec. The TDC also contains a separately-programmed data path that
produces prompt trigger data every Tevatron crossing. The full TDC design and
multi-card test results are described. The physical simplicity ensures
low-maintenance; the functionality being in firmware allows reprogramming for
other applications.


title:
Novel String Banana Template Method of Track Reconstruction for high
  Multiplicity Events with Significant Multiple Scattering

abstract:
  Novel String Banana Template Method (SBTM) for track reconstruction in high
multiplicity events in non-uniform magnetic field spectrometer with emphasis on
the lowest momenta tracks with significant Multiple Scattering (MS) is
described. Two steps model of track with additional parameter/s which takes
into account MS for this particular track is introduced. SBTM is time efficient
and demonstrates better resolutions than another method equivalent to the Least
Squares method (LSM).


title: Efficient numerical integrators for stochastic models

abstract:
  The efficient simulation of models defined in terms of stochastic
differential equations (SDEs) depends critically on an efficient integration
scheme. In this article, we investigate under which conditions the integration
schemes for general SDEs can be derived using the Trotter expansion. It follows
that, in the stochastic case, some care is required in splitting the stochastic
generator. We test the Trotter integrators on an energy-conserving Brownian
model and derive a new numerical scheme for dissipative particle dynamics. We
find that the stochastic Trotter scheme provides a mathematically correct and
easy-to-use method which should find wide applicability.


title: Calorimeters in Astro and Particle physics

abstract:
  In this article an attempt is made to review some of the original works
leading to new developments of calorimeters which are so widely and
successfully used in astro and particle physics experiments. This report is far
from being complete and the author apologizes for omissions and misquotations.


title: Structure and Evolution of the World Trade Network

abstract:
  The \emph{World Trade Web} (WTW), the network defined by the international
import/export trade relationships, has been recently shown to display some
important topological properties which are tightly related to the Gross
Domestic Product of world countries. While our previous analysis focused on the
static, undirected version of the WTW, here we address its full evolving,
directed description. This is accomplished by exploiting the peculiar
reciprocity structure of the WTW to recover the directed nature of
international trade channels, and by studying the temporal dependence of the
parameters describing the WTW topology.

categories: physics.soc-ph cond-mat.dis-nn nlin.AO q-fin.GN


title:
The power of a good idea: quantitative modeling of the spread of ideas
  from epidemiological models

abstract:
  The population dynamics underlying the diffusion of ideas hold many
qualitative similarities to those involved in the spread of infections. In
spite of much suggestive evidence this analogy is hardly ever quantified in
useful ways. The standard benefit of modeling epidemics is the ability to
estimate quantitatively population average parameters, such as interpersonal
contact rates, incubation times, duration of infectious periods, etc. In most
cases such quantities generalize naturally to the spread of ideas and provide a
simple means of quantifying sociological and behavioral patterns. Here we apply
several paradigmatic models of epidemics to empirical data on the advent and
spread of Feynman diagrams through the theoretical physics communities of the
USA, Japan, and the USSR in the period immediately after World War II. This
test case has the advantage of having been studied historically in great
detail, which allows validation of our results. We estimate the effectiveness
of adoption of the idea in the three communities and find values for parameters
reflecting both intentional social organization and long lifetimes for the
idea. These features are probably general characteristics of the spread of
ideas, but not of common epidemics.


title:
A novel String Banana Template Method for Tracks Reconstruction in High
  Multiplicity Events with significant Multiple Scattering and its Firmware
  Implementation

abstract:
  Novel String Banana Template Method (SBTM) for track reconstruction in
difficult conditions is proposed and implemented for off-line analysis of
relativistic heavy ion collision events.
  The main idea of the method is in use of features of ensembles of tracks
selected by 3-fold coincidence. Two steps model of track is used: the first one
- averaged over selected ensemble and the second - per event dependent.
  It takes into account Multiple Scattering (MS) for this particular track.
SBTM relies on use of stored templates generated by precise Monte Carlo
simulation, so it's more time efficient for the case of 2D spectrometer.
  All data required for track reconstruction in such difficult conditions could
be prepared in convenient format for fast use. Its template based nature and
the fact that the SBTM track model is actually very close to the hits implies
that it can be implemented in a firmware processor. In this report a block
diagram of firmware based pre-processor for track reconstruction in CMS-like Si
tracker is proposed.


title: Instability of Taylor-Couette Flow between Concentric Rotating Cylinders

abstract:
  The energy gradient theory is used to study the instability of Taylor-Couette
flow between concentric rotating cylinders. This theory has been proposed in
our previous works. In our previous studies, the energy gradient theory was
demonstrated to be applicable for wall-bounded parallel flows. It was found
that the critical value of the energy gradient parameter Kmax at turbulent
transition is about 370-389 for wall-bounded parallel flows (which include
plane Poiseuille flow, pipe Poiseuille flow and plane Couette flow) below which
no turbulence occurs. In this paper, the detailed derivation for the
calculation of the energy gradient parameter in the flow between concentric
rotating cylinders is provided. The calculated results for the critical
condition of primary instability (with semi-empirical treatment) are found to
be in very good agreement with the experiments in the literature. A possible
mechanism of spiral turbulence generation observed for counter-rotation of two
cylinders can also be explained using the energy gradient theory. The energy
gradient theory can serve to relate the condition of transition in
Taylor-Couette flow to that in plane Couette flow. The latter reasonably
becomes the limiting case of the former when the radii of cylinders tend to
infinity. It is our contention that the energy gradient theory is possibly
fairly universal for analysis of flow instability and turbulent transition, and
is found valid for both pressure and shear driven flows in parallel and
rotating flow configurations.


title: Controllable soliton dragging by dynamical optical lattices

abstract:
  We report on the phenomenon of controllable soliton dragging by dynamical
optical lattices induced by three imbalanced interfering plane waves. Because
of such an imbalance, the transverse momentum of the lattice does not vanish,
and thus the dynamical lattice can cause soliton dragging. The dragging rate is
shown to depend on the amplitude and on the angle of incidence of the third
plane wave making the optical lattice.


title:
Performance of a Large Area Avalanche Photodiode in a Liquid Xenon
  Ionization and Scintillation Chamber

abstract:
  Scintillation light produced in liquid xenon (LXe) by alpha particles,
electrons and gamma-rays was detected with a large area avalanche photodiode
(LAAPD) immersed in the liquid. The alpha scintillation yield was measured as a
function of applied electric field. We estimate the quantum efficiency of the
LAAPD to be 45%. The best energy resolution from the light measurement at zero
electric field is 7.5%(sigma) for 976 keV internal conversion electrons from
Bi-207 and 2.6%(sigma) for 5.5 MeV alpha particles from Am-241. The detector
used for these measurements was also operated as a gridded ionization chamber
to measure the charge yield. We confirm that using a LAAPD in LXe does not
introduce impurities which inhibit the drifting of free electrons.


title: A Dyad Theory of Hydrodynamics and Electrodynamics

abstract:
  The dyadic calculus is developed in a form suitable for the description of
physical relations in curved space. The 4-space equations of hydrodynamics and
electrodynamics are constructed using this dyadic calculus. As a demonstration
of the relationship between gravity and electrodynamics a time varying metric
is shown to generate electromagnetic radiation.


title: Cold atoms in videotape micro-traps

abstract:
  We describe an array of microscopic atom traps formed by a pattern of
magnetisation on a piece of videotape. We describe the way in which cold atoms
are loaded into one of these micro-traps and how the trapped atom cloud is used
to explore the properties of the trap. Evaporative cooling in the micro-trap
down to a temperature of 1 microkelvin allows us to probe the smoothness of the
trapping potential and reveals some inhomogeneity produced by the magnetic
film. We discuss future prospects for atom chips based on microscopic
permanent-magnet structures.


title: Flawing CERN antihydrogen-experiments with the available H-spectrum

abstract:
  Solving the antiH-problem could well be of historical interest but a solution
must be unambiguous. We use already available and accurate spectral evidence to
contradict and even to flaw the current CERN antiH-experiments, set up to
unravel this antiH-mystery. Making antiH with a long-range interaction between
e+ and p- is impossible, since this mass-asymmetrical pair of charge-conjugated
antiparticles is confined to a bound state at close-range. This resembles the
short- and long-range quark behavior in QCD. A real solution for antiH will
therefore require a different approach.


title:
Effects of Pulsed Low Frequency Electromagnetic Fields on Water
  Characterized by Light Scattering Techniques: Role of Bubbles

abstract: This paper has been withdrawn by the author.


title:
Effects of pulsed low frequency electromagnetic fields on water using
  photoluminescence spectroscopy: role of bubble/water interface

abstract:
  The effects of a pulsed low frequency electromagnetic field were investigated
on photoluminescence of well characterized water and prepared under controlled
conditions (container, atmospheric, electromagnetic, and acoustic
environments). When reference water samples were excited at 260 nm, two wide
emission bands centered at 345 nm (3.6 eV) and 425 nm (2.9 eV) were observed.
By contrast under 310 nm excitation, only one band appeared at 425 nm.
Interestingly, electromagnetic treatment (EMT) induced, at both excitation
wavelengths, a decrease (around 70%) in the 425 nm band relative
photoluminescence intensity. However, no difference between reference and
treated sample was observed in the 345 nm band. Other experiments, performed on
outgassed samples (reference and treated), show that the emission bands
(position, shape, intensity) under excitation at 260 nm and 310 nm were similar
and close to the corresponding bands of the treated nonoutgassed samples.
Similar effects were observed on photoluminescence excitation of water samples.
Two excitation bands monitored at 425 nm were observed at 272 nm and 330 nm.
After EMT and/or outgassing, a decrease (> 60%) was observed in the intensity
of these two bands. Altogether, these results indicate that electromagnetic
treatment and/or outgassing decrease in a similar fashion the photoluminescence
intensity in water samples. They also suggest that this effect is most likely
indirectly attributed to the presence of gas bubbles in water. The possible
role of hydrated ionic shell around the bubbles in the observed
extraluminescence is discussed.


title:
Raman Scattering of Water and Photoluminescence of Pollutants Arising
  from Solid-Water Interaction

abstract:
  Systematic Raman experiments performed on water and water-ethanol samples,
stored in different containers (fused silica, polypropylene, soda-lime glass
type III) for several hours, have shown that the luminescence contribution to
the Raman signal fluctuations is directly related to the container composition.
Intensity fluctuations as large as 98%, have been observed in the spectral
regions corresponding to the both water intramolecular and intermolecular
vibrations, despite the fact that the wavenumbers of the modes remained
unchanged. We undoubtedly attribute these fluctuations to a luminescence
phenomenon on the basis of : i) the absence of such effect in the anti-Stokes
domain, ii) its dependence on the excitation laser wavelength, iii) other
relevant photoluminescence experiments. This luminescence is attributed to
pollutants at ultra-low concentration coming from the different containers.


title: Contamination by metallic elements released from joint prostheses

abstract:
  When a metallic implant is in contact with human tissues, the organism reacts
and a corrosion process starts. Consequently, we might observe liberation of
metallic debris and wear. Our purpose is to measure the contamination and the
migration of these metallic elements in the surrounding tissues of the implant.
Two types of samples have been studied. First type is sample taken on
post-mortem tissues around prostheses to study contamination gradients. Second
type is sample taken on pathologic joints on periprosthetic capsular tissues in
surgical conditions. These allow estimating contamination degree. The
experiments were made on a Van de Graaff accelerator located at CERI (Centre
d'Etude et de Recherche par Irradiation, Orl\'{e}ans, France). We measure
elemental concentrations resulting from the contamination of the surface of
each sample. Results are analysed in function of the pathology and the type of
implants. According to the pathology and the location of the sampling, these
measurements show a very heterogeneous contamination by metallic elements under
particles and/or ionic species which can migrate through soft tissues by
various mechanisms


title: Time and Frequency description of Optical Pulses

abstract:
  The connection between the time-dependent physical spectrum of light and the
phase space overlap of Wigner functions is investigated for optical pulses.
Time and frequency properties of optical pulses with chirp are analyzed using
the phase space Wigner and Ambiguity distribution functions. It is shown that
optical pulses can exhibit interesting phenomena, very much reminiscent of
quantum mechanical interference, quantum entanglement of wave packets, and
quantum sub-Planck structures of the time and frequency phase space.


title: Pneumatic capillary gun for ballistic delivery of microparticles

abstract:
  A pneumatic gun for ballistic delivery of microparticles to soft targets is
proposed and demonstrated. The particles are accelerated by a high speed flow
of Helium in a capillary tube. Vacuum suction applied to a concentric, larger
diameter tube is used to divert substantially all of the flow of Helium from
the gun nozzle, thereby preventing the gas from hitting and damaging the
target. Speed of ejection of micron-sized gold particles from the gun nozzle,
and their depth of penetration into agarose gels are reported.


title: Statistical Properties of Business Firms Structure and Growth

abstract:
  We analyze a database comprising quarterly sales of 55624 pharmaceutical
products commercialized by 3939 pharmaceutical firms in the period 1992--2001.
We study the probability density function (PDF) of growth in firms and product
sales and find that the width of the PDF of growth decays with the sales as a
power law with exponent $\beta = 0.20 \pm 0.01$. We also find that the average
sales of products scales with the firm sales as a power law with exponent
$\alpha = 0.57 \pm 0.02$. And that the average number products of a firm scales
with the firm sales as a power law with exponent $\gamma = 0.42 \pm 0.02$. We
compare these findings with the predictions of models proposed till date on
growth of business firms.


title: A Generalized Preferential Attachment Model for Complex Systems

abstract:
  Complex systems can be characterized by classes of equivalency of their
elements defined according to system specific rules. We propose a generalized
preferential attachment model to describe the class size distribution. The
model postulates preferential growth of the existing classes and the steady
influx of new classes. We investigate how the distribution depends on the
initial conditions and changes from a pure exponential form for zero influx of
new classes to a power law with an exponential cutoff form when the influx of
new classes is substantial. We apply the model to study the growth dynamics of
pharmaceutical industry.


title: Scaling Phenomena in the Growth Dynamics of Scientific Output

abstract:
  We analyze a set of three databases at different levels of aggregation (i) a
database of approximately $10^6$ publications of 247 countries in the period
between 1980--2001. (ii) A database of 508 academic institutions from European
Union (EU) and 408 institutes from USA in the 11 year period between during
1991--2001. (iii) A database comprising of 2330 Flemish authors in the period
1980--2000. At all levels of aggregation we find that the mean annual growth
rates of publications is independent of the number of publications of the
various units involved. We also find that the standard deviation of the
distribution of annual growth rates decays with the number of publications as a
power law with exponent $\approx 0.3$. These findings are consistent with those
of recent studies of systems such as the size of R&D funding budgets of
countries, the research publication volumes of US universities, and the size of
business firms.


title: Statistical Properties of Demand Fluctuation in the Financial Market

abstract:
  We examine the out-of-equilibrium phase reported by Plerou {\it et. al.} in
Nature, {\bf 421}, 130 (2003) using the data of the New York stock market
(NYSE) between the years 2001 --2002. We find that the observed two phase
phenomenon is an artifact of the definition of the control parameter coupled
with the nature of the probability distribution function of the share volume.
We reproduce the two phase behavior by a simple simulation demonstrating the
absence of any collective phenomenon. We further report some interesting
statistical regularities of the demand fluctuation of the financial market.


title:
Global monitoring of tropospheric water vapor with GPS radio occultation
  aboard CHAMP

abstract:
  The paper deals with application of GPS radio occultation (RO) measurements
aboard CHAMP for the retrieval of tropospheric water vapor profiles. The GPS RO
technique provides a powerful tool for atmospheric sounding which requires no
calibration, is not affected by clouds, aerosols or precipitation, and provides
an almost uniform global coverage. We briefly overview data processing and
retrieval of vertical refractivity, temperature and water vapor profiles from
GPS RO observations. CHAMP RO data are available since 2001 with up to 200 high
resolution atmospheric profiles per day. Global validation of CHAMP water vapor
profiles with radiosonde data reveals a bias of about 0.2 g/kg and a standard
deviation of less than 1 g/kg specific humidity in the lower troposphere. We
demonstrate potentials of CHAMP RO retrievals for monitoring the mean
tropospheric water vapor distribution on a global scale.


title: Prototype scintillator cell for an In-based solar neutrino detector

abstract:
  We describe the work carried out at MPIK to design, model, build and
characterize a prototype cell filled with a novel indium-loaded scintillator of
interest for real-time low energy solar neutrino spectroscopy. First, light
propagation in optical modules was studied with experiments and Monte Carlo
simulations. Subsequently a 5 cm x 5 cm x 100 cm prototype detector was set up
and the optical performances of several samples were measured. We first tested
a benchmark PXE-based scintillator, which performed an attenuation length of ~
4.2 m and a photo-electron yield of ~ 730 pe/MeV. Then we measured three
In-loaded samples. At an In-loading of 44 g/l, an energy resolution of ~ 11.6 %
and a spatial resolution of ~ 7 cm were attained for 477 keV recoil electrons.
The long-range attenuation length in the cell was ~1.3 m and the estimated
photo-electron yield ~ 200 pe/MeV. Light attenuation and relative light output
of all tested samples could be reproduced reasonably well by MC. All optical
properties of this system have remained stable over a period of > 1 y.


title:
Strong Orientation Effects in Ionization of H$_2^+$ by Short, Intense,
  High-Frequency Light Sources

abstract:
  We present three dimensional time-dependent calculations of ionization of
arbitrarily spatially oriented H$_2^+$ by attosecond, intense, high-frequency
laser fields. The ionization probability shows a strong dependence on both the
internuclear distance and the relative orientation between the laser field and
the internuclear axis.


title: The Significance of the General Principle of Relativity

abstract:
  In this note, we discuss the significance of the general principle of
relativity for a physical theory that abandons the newtonian concept of force
and, hence, uses an entirely different conception for the ``cause'' behind
motions of material bodies.


title: No GW is emitted by B PSR1913+16

abstract:
  In the exact (non-linear) formulation of general relativity (GR) no motion of
bodies can give origin to gravitational waves (GW's) - as it has been proved.
Accordingly, the measured rate of change of the orbital period of binary pulsar
B PSR1913+16 must have other causes, different from the emission of GW's; maybe
the viscous losses of the unseen pulsar companion, if it were e.g. a helium
star.


title: Lifetime Measurement of the 6s Level of Rubidium

abstract:
  We present a lifetime measurements of the 6s level of rubidium. We use a
time-correlated single-photon counting technique on two different samples of
rubidium atoms. A vapor cell with variable rubidium density and a sample of
atoms confined and cooled in a magneto-optical trap. The 5P_{1/2} level serves
as the resonant intermediate step for the two step excitation to the 6s level.
We detect the decay of the 6s level through the cascade fluorescence of the
5P_{3/2} level at 780 nm. The two samples have different systematic effects,
but we obtain consistent results that averaged give a lifetime of 45.57 +- 0.17
ns.


title: Viscous Flow Instability of Inflectional Velocity Profile

abstract:
  Rayleigh showed that inviscid flow is unstable if the velocity profile has an
inflection point in parallel flows. However, whether viscous flows is unstable
or not is still not proved so far when there is an inflection point in the
velocity profile. Fluid viscosity has showed dual role to the flow instability.
In this paper, it is demonstrated for the first time that viscous parallel flow
with inflectional velocity profile is sufficient for flow instability.


title:
Chiral Tetrahedrons as Unitary Quaternions: Molecules and Particles
  Under the Same Standard?

abstract:
  Chiral tetrahedral molecules can be dealt under the standard of quaternionic
algebra. Specifically, non-commutativity of quaternions is a feature directly
related to the chirality of molecules. It is shown that a quaternionic
representation naturally comes out from empirical Fischer projections and the
action of the related algebra on the quantum states of molecules is studied.
Analogies with fundamental particle physics are discussed.


title:
Parameterizing Quasiperiodicity: Generalized Poisson Summation and Its
  Application to Modified-Fibonacci Antenna Arrays

abstract:
  The fairly recent discovery of "quasicrystals", whose X-ray diffraction
patterns reveal certain peculiar features which do not conform with spatial
periodicity, has motivated studies of the wave-dynamical implications of
"aperiodic order". Within the context of the radiation properties of antenna
arrays, an instructive novel (canonical) example of wave interactions with
quasiperiodic order is illustrated here for one-dimensional (1-D) array
configurations based on the "modified-Fibonacci" sequence, with utilization of
a two-scale generalization of the standard Poisson summation formula for
periodic arrays. This allows for a "quasi-Floquet" analytic parameterization of
the radiated field, which provides instructive insights into some of the basic
wave mechanisms associated with quasiperiodic order, highlighting similarities
and differences with the periodic case. Examples are shown for quasiperiodic
infinite and spatially-truncated arrays, with brief discussion of computational
issues and potential applications.


title:
Radiation Properties of One-Dimensional Quasirandom Antenna Arrays Based
  on Rudin-Shapiro Sequences

abstract:
  The development of exotic new materials, such as metamaterials, has created
strong interest within the electromagnetics (EM) community for possible new
phenomenologies and device applications, with particular attention to
periodicity-induced phenomena, such as photonic bandgaps (PBG). Within this
context, motivated by the fairly recent discovery in X-ray crystallography of
"quasicrystals," whose diffraction patterns display unusual characteristics
that are associated with "aperiodic order," we have undertaken a systematic
study of how these exotic effects manifest themselves in the radiation
properties of aperiodically-configured antenna arrays. The background for these
studies, with promising example configurations, has been reported in a previous
publication [V. Pierro et al., IEEE Trans. Antennas Propagat., vol. 53, No. 2,
pp. 635-644, Feb. 2005]. In the present paper, we pay attention to various
configurations generated by Rudin-Shapiro (RS) sequences, which constitute one
of the simplest conceivable examples of deterministic aperiodic geometries
featuring quasirandom (dis)order. After presentation and review of relevant
background material, the radiation properties of one-dimensional RS-based
antenna arrays are analyzed, followed by illustrative numerical parametric
studies to validate the theoretical models. Design parameters and potential
practical applications are also given attention.


title: From one space dimension to two space dimensions in special relativity

abstract:
  Authors derive the Lorentz-Einstein transformation for the space-time
coordinates starting with a one-space dimension approach. They add to the
results the invariance of the space coordinates measured perpendicular to the
direction of relative motion. Students often ask if the transition does not
affect the transformation equation for the time coordinate. Our paper shows
that the transformation of the time coordinate depends only on the x space
coordinate.


title: Generic solution for hydrogen-antihydrogen interactions

abstract:
  An internal inconsistency with mutually exclusive Hamiltonians and the
corresponding mutually exclusive states HH and H-antiH suffices to doubt the
usefulness of ab initio calculations for H-antiH based on 1927 Heitler-London
theory. Removing this inconsistency in a generic way invalidates this theory
but the compensation is that problems with antihydrogen are removed.


title:
Characterization of the initial filamentation of a relativistic electron
  beam passing through a plasma

abstract:
  The linear instability that induces a relativistic electron beam passing
through a return plasma current to filament transversely is often related to
some filamentation mode with wave vector normal to the beam or confused with
Weibel modes. We show that these modes may not be relevant in this matter and
identify the most unstable mode on the two-stream/filamentation branch as the
main trigger for filamentation. This sets both the characteristic transverse
and longitudinal filamentation scales in the non-resistive initial stage.


title:
Equivalence of macro- (Van der waals) and micro- (quantum)
  phase-transitions: consequences for BEC, antihydrogen and generic chiral
  symmetry breaking

abstract:
  The internal microscopic phase transition in atom H described with a
Hund-type Mexican hat potential is analytically congruent with the macroscopic
phase transitions between states of aggregation, described with classical Van
der waals-Maxwell binodals and spinodals. This means the UEOS (universal
equation of state) exists and is valid for any phase transition in any system.
A universal chiral symmetry breaking mechanism applies to BEC, where the de
Broglie length is important. We show quantitatively that his standing wave
equation leads to the equivalence of macro- and microscopic phase transitions,
due to natural chiral symmetry breaking. The experimentally detected phase
transition in the so-called simple Coulomb electron-proton bond between the 2
enantiomers H and antiH is the generic prototype.


title: Threshold amplitudes for transition to turbulence in a pipe

abstract:
  Threshold amplitude of disturbance for transition to turbulence in a pipe
Poiseuille flow is investigated. Based on the energy gradient theory, we argued
that the transition to turbulence depends on magnitudes of the energy gradient
of mean flow and the disturbance energy. Furthermore, the threshold disturbance
energy required for turbulence transition is expressed as a function of the
complementary angle to the energy angle which also characterizes the behaviour
of the energy gradient of mean flow. With some mathematical treatments, the
variation of the threshold energy of disturbance versus the Reynolds number is
obtained. Then, it is found for a fixed disturbance frequency that the
normalized amplitude of disturbance is scaled by Re with an exponent of -3/2
for the transition occurrence in a pipe. This value of exponent agrees well
with several recent results reported in the literature. Finally, the mechanism
of transition to turbulence is suggested for different disturbance levels.


title:
Use of time-correlated single photon counting detection to measure the
  speed of light in water

abstract:
  Traditional methods for measuring the speed of light in dispersive media have
been based on the detection of interference between light waves emitted from
the same source. In the present study the elapsed times for single photons to
move from a laser to a photomultiplier tube are measured electronically.
Time-correlated single photon counting detection produces a characteristic
instrument response which has the same shape independent of both the path
length the light travels and the nature of the transparent media through which
it passes. This allows for an accurate calibration of the chronograph by
observing shifts in the location of the instrument response for different
distances traveled by the light. Measurement of the corresponding shift which
occurs when light moves the same distance through air and water then enables an
accurate determination of the ratio of the photon velocities in these two
media. Three different wavelengths of light have been used. In two cases good
agreement is found between the present measured light speeds and those which
can be inferred from existing refractive index measurements in water. The
shortest wavelength studied is too far in the uv to obtain a reliable estimate
on the same basis, and so the ng value (1.463) measured in the present work
awaits independent confirmation. A theoretical discussion of the present
results is undertaken with reference to Newton's original corpuscular theory of
light. It is argued that his failure to predict that light travels more slowly
in water than in air arose from the inadequacy of his mechanical theory rather
than his assumptions about the elementary composition of light.


title: Recombination of atomic Hydrogen physisorbed on low-temperature Surfaces

abstract:
  Molecular beam experiments that use low-temperature bolometers as (energy-)
detectors are well suited to the study of physisorption and recombination of
hydrogen on low-temperature surfaces. Experiments where this technique is
combined with mass spectrometry to examine atoms and molecules released from
the surface are summarised and reviewed with reference to astrophysical
implications. Hydrogen atoms physisorbed on polycrystalline water ice are shown
to be sufficiently mobile to recombine efficiently even at surface temperatures
as low as 3 K. Molecules are formed with substantial internal energy, probably
of the order of 35000 K, and are immediately released when formed. Coverage by
molecular hydrogen plays an important role in determining overall recombination
efficiency and may self-regulate recombination in interstellar clouds: on
hydrogen-free grains recombination is limited by the low sticking coefficient
of hydrogen atoms, while on grains covered by molecular hydrogen the binding
energy is reduced so that recombination is limited by the rapid evaporation of
physisorbed atoms.


title: Real time noninvasive cancer diagnostics

abstract:
  Laser illumination of tissue results in a characteristic fluorescence
emission spectrum whose features depend on the type of tissue, viz., healthy,
adenoma or malignant. Hence measurement of the fluorescence is potentially a
rapid and reliable diagnostic method. We have applied the technique to thyroid
tissues and found that judicious normalization of the fluorescence spectrum
reveals a close correlation between spectral shape and tissue type. Hence the
pathological state of the tissue can be unambiguously identified from the
laser-induced fluorescence spectrum. The method is rapid and portable and is
therefore eminently suitable for use during operations.


title:
A Compact Apparatus for Muon Lifetime Measurement and Time Dilation
  Demonstration in the Undergraduate Laboratory

abstract:
  We describe a compact apparatus that automatically measures the charge
averaged lifetime of atmospheric muons in plastic scintillator using low-cost,
low-power electronics and that measures the stopping rate of atmospheric muons
as a function of altitude to demonstrate relativistic time dilation. The
apparatus is designed for the advanced undergraduate physics laboratory and is
suitable for field measurements.


title:
Calculation of the energy levels of Ge, Sn, Pb and their ions in the
  $V^{N-4}$ approximation

abstract:
  Energy levels of germanium, tin and lead together with their single, double
and triple ionized positive ions have been calculated using the $V^{N-M}$
approximation suggested in the previous work (Dzuba, physics/0501032) (M=4 -
number of valence electrons). Initial Hartree-Fock calculations are done for
the quadruply ionized ions with all valence electrons removed. The core-valence
correlations are included beyond the second-order of the many-body perturbation
theory. Interaction between valence electrons is treated by means of the
configuration interaction technique. It is demonstrated that accurate treatment
of the core-valence correlations lead to systematic improvement of the accuracy
of calculations for all ions and neutral atoms.


title: Theory of Frozen Waves

abstract:
  In this work, starting by suitable superpositions of equal-frequency Bessel
beams, we develop a theoretical and experimental methodology to obtain
localized stationary wave fields, with high transverse localization, whose
longitudinal intensity pattern can approximately assume any desired shape
within a chosen interval 0 < z < L of the propagation axis z. Their intensity
envelope remains static, i.e. with velocity v=0; so that we have named ``Frozen
Waves" (FW) these new solutions to the wave equations (and, in particular, to
the Maxwell equations). Inside the envelope of a FW only the carrier wave does
propagate: And the longitudinal shape, within the interval 0 < z < L, can be
chosen in such a way that no nonnegligible field exists outside the
pre-determined region (consisting, e.g., in one or more high intensity peaks).
Our solutions are noticeable also for the different and interesting
applications they can have, especially in electromagnetism and acoustics, such
as optical tweezers, atom guides, optical or acoustic bistouries, various
important medical apparata, etc.


title: Noncommutative spacetime effects and gravitation

abstract:
  In recent years Quantum Superstrings and Quantum Gravity approaches have come
to rely on non differenciable spacetime manifolds. These throw up a
noncommutative spacetime geometry and we consider the origin of mass and a
related modification of the Dirac equation in this context. This also throws
some light on gravitation itself.


title:
Exact Nondipole Kramers-Henneberger Form of the Light-Atom Hamiltonian:
  An Application to Atomic Stabilization and Photoelectron Energy Spectra

abstract:
  The exact nondipole minimal-coupling Hamiltonian for an atom interacting with
an explicitly time- and space-dependent laser field is transformed into the
rest frame of a classical free electron in the laser field, i.e., into the
Kramers-Henneberger frame. The new form of the Hamiltonian is used to study
nondipole effects in the high-intensity, high-frequency regime. Fully three
dimensional nondipole {\it ab initio} wavepacket calculations show that the
ionization probability may decrease for increasing field strength. We identify
a unique signature for the onset of this dynamical stabilization effect in the
photoelectron spectrum.


title: Topology hidden behind the breakdown of adiabaticity

abstract:
  For classical Hamiltonian systems, the adiabatic condition may fail at some
critical points. However, the breakdown of the adiabatic condition does not
always make the adiabatic evolution be destroyed. In this paper, we suggest a
supplemental condition of the adiabatic evolution for the fixed points of
classical Hamiltonian systems when the adiabatic condition breaks down at the
critical points. As an example, we investigate the adiabatic evolution of the
fixed points of a classical Hamiltonian system which has a number of
applications.


title: Quantum Correction in Exact Quantization Rules

abstract:
  An exact quantization rule for the Schr\"{o}dinger equation is presented. In
the exact quantization rule, in addition to $N\pi$, there is an integral term,
called the quantum correction. For the exactly solvable systems we find that
the quantum correction is an invariant, independent of the number of nodes in
the wave function. In those systems, the energy levels of all the bound states
can be easily calculated from the exact quantization rule and the solution for
the ground state, which can be obtained by solving the Riccati equation. With
this new method, we re-calculate the energy levels for the one-dimensional
systems with a finite square well, with the Morse potential, with the symmetric
and asymmetric Rosen-Morse potentials, and with the first and the second
P\"{o}schl-Teller potentials, for the harmonic oscillators both in one
dimension and in three dimensions, and for the hydrogen atom.


title: Time reversal noninvariance in quantum mechanics and in nonlinear optics

abstract:
  The experimental proofs of strong time invariance violation in optics are
discussed. Time noninvariance is the only real physical base for explanation
the origin of the most phenomena in nonlinear optics. The experimental study of
forward and reversed transitions in oriented in uniform electric field
molecules is proposed.


title: 100 ps time-of-flight resolution of Dielectric Resistive Plate Chamber

abstract:
  Time of flight of a minimum ionizing particle along a fixed base has been
measured with a 100 ps accuracy by means of a Dielectric Resistive Plate
Chamber (DRPC) with 4 x 0.3 mm gas gaps. DRPC timing characteristics have been
studied with different applied voltages, discriminating thresholds and beam
intensities. It may be stated that the time-of-flight resolution of gaseous
detectors developed within the ALICE experiment has reached the level of the
best known scintillation counters.


title:
Simulation of geometric and electronic degrees of freedom using a
  kink-based path integral formulation: application to molecular systems

abstract:
  A kink-based path integral method, previously applied to atomic systems, is
modified and used to study molecular systems. The method allows the
simultaneous evolution of atomic and electronic degrees of freedom. Results for
CH$_4 $, NH$_3 $, and H$_2 $O demonstrate this method to be accurate for both
geometries and energies. Comparison with DFT and MP2 level calculations show
the path integral approach to produce energies in close agreement with MP2
energies and geometries in close agreement with both DFT and MP2 results.


title: Precision measurement of light shifts in a single trapped Ba$^+$ ion

abstract:
  Using a single trapped barium ion we have developed an rf spectroscopy
technique to measure the ratio of the off-resonant vector ac Stark effect (or
light shift) in the 6S_{1/2} and 5D_{3/2} states to 0.1% precision. We find R =
Delta_S / Delta_D = -11.494(13) at 514.531 nm where Delta_{S,D} are the light
shifts of the m = +/- 1/2 splittings due to circularly polarized light.
Comparison of this result with an ab initio calculation of R would yield a new
test of atomic theory. By appropriately choosing an off-resonant light shift
wavelength one can emphasize the contribution of one or a few dipole matrix
elements and precisely determine their values.


title:
Field of the Current Pulse Moving Along the Straight Line with Super
  Light Velocity

abstract:
  A simulation of electric current pulses formed by a packet of gamma-quanta
moving through an absorptive medium is presented. The electromagnetic fields of
the current pulse moving along the straight line with super light velocity are
obtained


title: Special relativity in terms of Lie groups

abstract:
  The special theory of relativity is constructed demanding the retention of
the rectilinear form of a trajectory and invariance of the wave equation under
linear transformations of space and time coordinates. The usual approach to
relativity based on manipulations with the impulse of light is shown to be
owing to that the symmetry of the particular solution of the wave equation
coincides with the symmetry of the very wave equation. Thereof instead of the
equation in partial derivatives we may deal with the algebraic form referred to
as the interval.


title:
Two-dimensional array of multicolored upconverted parametric
  amplification

abstract: This paper has been withdrawn by the authors


title: Cold atom Clocks and Applications

abstract:
  This paper describes advances in microwave frequency standards using
laser-cooled atoms at BNM-SYRTE. First, recent improvements of the $^{133}$Cs
and $^{87}$Rb atomic fountains are described. Thanks to the routine use of a
cryogenic sapphire oscillator as an ultra-stable local frequency reference, a
fountain frequency instability of $1.6\times 10^{-14}\tau^{-1/2}$ where $\tau $
is the measurement time in seconds is measured. The second advance is a
powerful method to control the frequency shift due to cold collisions. These
two advances lead to a frequency stability of $2\times 10^{-16}$ at $50,000s
for the first time for primary standards. In addition, these clocks realize the
SI second with an accuracy of $7\times 10^{-16}$, one order of magnitude below
that of uncooled devices. In a second part, we describe tests of possible
variations of fundamental constants using $^{87}$Rb and $^{133}$Cs fountains.
Finally we give an update on the cold atom space clock PHARAO developed in
collaboration with CNES. This clock is one of the main instruments of the
ACES/ESA mission which is scheduled to fly on board the International Space
Station in 2008, enabling a new generation of relativity tests.


abstract:
  Numerical simulations are reported on the Bonabeau model on a fully connected
graph, where spatial degrees of freedom are absent. The control parameter is
the memory factor f. The phase transition is observed at the dispersion of the
agents power h_i. The critical value f_C shows a hysteretic behavior with
respect to the initial distribution of h_i. f_C decreases with the system size;
this decrease can be compensated by a greater number of fights between a global
reduction of the distribution width of h_i. The latter step is equivalent to a
partial forgetting.


title:
Additive-multiplicative stochastic models of financial mean-reverting
  processes

abstract:
  We investigate a generalized stochastic model with the property known as mean
reversion, that is, the tendency to relax towards a historical reference level.
Besides this property, the dynamics is driven by multiplicative and additive
Wiener processes. While the former is modulated by the internal behavior of the
system, the latter is purely exogenous. We focus on the stochastic dynamics of
volatilities, but our model may also be suitable for other financial random
variables exhibiting the mean reversion property. The generalized model
contains, as particular cases, many early approaches in the literature of
volatilities or, more generally, of mean-reverting financial processes. We
analyze the long-time probability density function associated to the model
defined through a It\^o-Langevin equation. We obtain a rich spectrum of shapes
for the probability function according to the model parameters. We show that
additive-multiplicative processes provide realistic models to describe
empirical distributions, for the whole range of data.


title: Paraxial Green's functions in Synchrotron Radiation theory

abstract:
  This work contains a systematic treatment of single particle Synchrotron
Radiation and some application to realistic beams with given cross section
area, divergence and energy spread. Standard theory relies on several
approximations whose applicability limits and accuracy are often forgotten. We
begin remarking that on the one hand, a paraxial approximation can always be
applied without loss of generality and with ultra relativistic accuracy. On the
other hand, dominance of the acceleration field over the velocity part in the
Lienard-Wiechert expressions is not always granted and constitutes a separate
assumption, whose applicability is discussed. Treating Synchrotron Radiation in
paraxial approximation we derive the equation for the slow varying envelope
function of the Fourier components of the electric field vector. Calculations
of Synchrotron Radiation properties performed by others showed that the phase
of the Fourier components of the electric field vector differs from the phase
of a virtual point source. In this paper we present a systematic, analytical
description of this phase shift, calculating amplitude and phase of electric
field from bending magnets, short magnets, two bending magnet system separated
by a straight section (edge radiation) and undulator devices. We pay particular
attention to region of applicability and accuracy of approximations used.
Finally, taking advantage of results of analytical calculation presented in
reduced form we analyze various features of radiation from a complex insertion
device (set of two undulators with a focusing triplet in between) accounting
for the influence of energy spread and electron beam emittance.


title: Spin tune in the single resonance model with a pair of Siberian Snakes

abstract:
  Snake ``resonances'' are classified in terms of the invariant spin field and
the amplitude dependent spin tune. Exactly at snake ``resonance'' there is no
continuous invariant spin field at most orbital amplitudes.


title: Mode interaction in multi-mode optical fibers with Kerr effect

abstract:
  We generalize the projection to orthogonal function basis (including
polarization modes) method for nonlinear (Kerr medium) fiber and use this
method in a case of two-mode waveguide. We consider orthogonal Bessel functions
basis that fit the choice of cylindrical geometry of a fiber. The coupled
nonlinear Schr\"{o}dinger equations (CNLS) are derived. Analytic expressions
and numerical results for coupling coefficients are given; the fiber parameters
dependence is illustrated by plots.


title: Study of the Pioneer Anomaly: A Problem Set

abstract:
  Analysis of the radio-metric tracking data from the Pioneer 10 and 11
spacecraft at distances between 20--70 astronomical units from the Sun has
consistently indicated the presence of an anomalous, small, and constant
Doppler frequency drift. The drift is a blue-shift, uniformly changing at the
rate of (5.99 +/- 0.01) x 10^{-9} Hz/s. The signal also can be interpreted as a
constant acceleration of each particular spacecraft of (8.74 +/- 1.33) x
10^{-8} cm/s^2 directed toward the Sun. This interpretation has become known as
the Pioneer anomaly. We provide a problem set based on the detailed
investigation of this anomaly, the nature of which remains unexplained.


title:
Superresolution and Duality for Time-Reversal of Waves in Self-Similar
  Media

abstract:
  We analyze the time reversal of waves in a turbulent medium using the
parabolic Markovian model. We prove that the time reversal resolution can be a
nonlinear function of the wavelength and independent of the aperture. We
establish a duality relation between the turbulence-induced wave spread and the
time-reversal resolution which can be viewed as an uncertainty inequality for
random media. The inequality becomes an equality when the wave structure
function is Gaussian.


title:
Investigation of transfer coefficients for many-component dense systems
  of neutral and charged hard spheres

abstract:
  In present work a calculation of transfer coefficients for many-component
dense gases for charged and non-charged hard spheres is carried out using the
Enskog-Landau kinetic equation which takes into account realistic particle
sizes.


title:
Pressure dependence of diffusion coefficient and orientational
  relaxation time for acetonitrile and methanol in water: DRISM/mode-coupling
  study

abstract:
  We present results of theoretical description and numerical calculation of
the dynamics of molecular liquids based on the Reference Interaction Site Model
/ Mode-Coupling Theory. They include the temperature-pressure(density)
dependence of the translational diffusion coefficients and orientational
relaxation times for acetonitrile and methanol in water at infinite dilution.
Anomalous behavior, i.e. the increase in mobility with density, is observed for
the orientational relaxation time of methanol, while acetonitrile does not show
any deviations from the usual. This effect is in qualitative agreement with the
recent data of MD simulation and with experimental measurements, which tells us
that presented theory is a good candidate to explain such kind of anomalies
from the microscopical point of view and with the connection to the structure
of the molecules.


title:
Study of anomalous mobility of polar molecular solutions by means of the
  site-site memory equation formalism

abstract:
  In this work, the memory equation approach is applied for theoretical study
of dynamics of polar molecular liquids described by the interaction site model.
The study includes the temperature-density(pressure) dependence of the
translational diffusion coefficients D and orientational relaxation times t for
infinitely dilute solutions of acetonitrile and methanol in water, and methanol
in acetonitrile. Calculations are performed over the range of temperatures and
densities employing the SPC/E model for water and optimized site-site
potentials for acetonitrile and methanol. Despite an approximate character of
the model potentials and closure relation used, the theory is able to reproduce
qualitatively all main features of temperature and density dependences of D and
t observed in computer and real experiments. In particular, anomalous behavior,
i.e. the increase in mobility with density(pressure), is obtained for D and t
of methanol in water, while acetonitrile in water or methanol in acetonitrile
do not show deviations from the usual. The observed enhancement in the
molecular mobility is interpreted in accordance with the concept by Yamaguchi
et al. [J. Chem. Phys. 119 (2003) 1021], i.e. in terms of two competing origins
of friction, which interplay with each other as density increases: the
collisional and dielectric frictions that have tendency, respectively, to
strengthen and weaken with increasing density.


title:
Site-site memory equation approach in study of density/pressure
  dependence of translational diffusion coefficient and rotational relaxation
  time of polar molecular solutions: acetonitrile in water, methanol in water,
  and methanol in acetonitrile

abstract:
  We present results of theoretical study and numerical calculation of the
dynamics of molecular liquids based on combination of the memory equation
formalism and the reference interaction site model - RISM. Memory equations for
the site-site intermediate scattering functions are studied in the
mode-coupling approximation for the first order memory kernels, while
equilibrium properties such as site-site static structure factors are deduced
from RISM. The results include the temperature-density(pressure) dependence of
translational diffusion coefficients D and orientational relaxation times t for
acetonitrile in water, methanol in water and methanol in acetonitrile, all in
the limit of infinite dilution. Calculations are performed over the range of
temperatures and densities employing the SPC/E model for water and optimized
site-site potentials for acetonitrile and methanol. The theory is able to
reproduce qualitatively all main features of temperature and density
dependences of D and t observed in real and computer experiments. In
particular, anomalous behavior, i.e. the increase in mobility with density, is
observed for D and t of methanol in water, while acetonitrile in water and
methanol in acetonitrile do not show deviations from the ordinary behavior. The
variety exhibited by the different solute-solvent systems in the density
dependence of the mobility is interpreted in terms of the two competing origins
of friction, which interplay with each other as density increases: the
collisional and dielectric frictions which, respectively, increase and decrease
with increasing density.


title: Lorenz or Coulomb in Galilean Electromagnetism ?

abstract:
  Galilean Electromagnetism was discovered thirty years ago by Levy-Leblond &
Le Bellac. However, these authors only explored the consequences for the fields
and not for the potentials. Following De Montigny & al., we show that the
Coulomb gauge condition is the magnetic limit of the Lorenz gauge condition
whereas the Lorenz gauge condition applies in the electric limit of
L\'{e}vy-Leblond & Le Bellac. Contrary to De Montigny & al. who used Galilean
tensor calculus, we use orders of magnitude based on physical motivations in
our derivation.


title:
Vector modulation instability induced by vacuum fluctuations in highly
  birefringent fibers in the anomalous dispersion regime

abstract:
  We report a detailed experimental study of vector modulation instability in
highly birefringent optical fibers in the anomalous dispersion regime. We prove
that the observed instability is mainly induced by vacuum fluctuations. The
detuning of the spectral peaks agrees with linear perturbation analysis. The
exact shape of the spectrum is well reproduced by numerical integration of
stochastic nonlinear Schrodinger equations describing quantum propagation.


title:
Thick GEM-like multipliers - a simple solution for large area UV-RICH
  detectors

abstract:
  We report on the properties of thick GEM-like (THGEM) electron multipliers
made of 0.4 mm thick double-sided Cu-clad G-10 plates, perforated with a dense
hexagonal array of 0.3 mm diameter drilled holes. Photon detectors comprising
THGEMs coupled to semi-transparent CsI photocathodes or reflective ones
deposited on the THGEM surface were studied with Ar/CO2 (70:30), Ar/CH4 (95:5),
CH4 and CF4. Gains of ~100000 or exceeding 1000000 were reached with single- or
double-THGEM, respectively; the signals have 5-10 ns rise times. The electric
field configurations at the THGEM electrodes result in an efficient extraction
of photoelectrons and their focusing into the holes; this occurs already at
rather low gains, below 100. These detectors, with single-photon sensitivity
and with expected sub-millimeter localization, can operate at MHz/mm2 rates. We
discuss their prospects for large-area UV-photon imaging for RICH.


title:
Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the
  UV and the visible spectral range

abstract:
  We report on the progress in the study of cascaded GEM and GEM/MHSP gas
avalanche photomultipliers operating at atmospheric pressure, with CsI and
bialkali photocathodes. They have single-photon sensitivity, ns time resolution
and good localization properties. We summarize operational aspects and results,
with the highlight of a high-gain stable gated operation of a visible-light
device. Of particular importance are the results of a recent ion-backflow
reduction study in different cascaded multipliers, affecting the detector's
stability and the photocathode's liftime. We report on the significant progress
in ion-blocking and provide first results on bialkali-photocathode aging under
gas multiplication.


title:
Complex-Dynamical Extension of the Fractal Paradigm and Its Applications
  in Life Sciences

abstract:
  Complex-dynamical fractal is a hierarchy of permanently, chaotically changing
versions of system structure, obtained as the unreduced, causally probabilistic
general solution of arbitrary interaction problem (physics/0305119,
physics/9806002). Intrinsic creativity of this extension of usual fractality
determines its exponentially high operation efficiency, which underlies many
specific functions of living systems, such as autonomous adaptability,
"purposeful" development, intelligence and consciousness (at higher complexity
levels). We outline in more detail genetic applications of complex-dynamic
fractality, demonstrate the dominating role of genome interactions, and show
that further progressive development of genetic research, as well as other
life-science applications, should be based on the dynamically fractal structure
analysis of interaction processes involved. We finally summarise the obtained
extension of mathematical concepts and approaches closely related to their
biological applications.


title:
Large-Eddy Simulation of Stably Stratified Atmospheric Boundary Layer
  Turbulence: A Scale-Dependent Dynamic Modeling Approach

abstract:
  A new tuning-free subgrid-scale model, termed `locally-averaged
scale-dependent dynamic' (LASDD) model, is developed and implemented in
large-eddy simulations (LESs) of stable boundary layers. The new model
dynamically computes the Smagorinsky coefficient and the subgrid-scale Prandtl
number based on the local dynamics of the resolved velocity and temperature
fields. Overall, the agreement between the statistics of the LES-generated
turbulence and some well-established empirical formulations and theoretical
predictions (e.g., Nieuwstadt's local scaling hypothesis) is remarkable. The
results show clear improvements over most of the traditional subgrid-scale
models in the surface layer. Moreover, in contrast to previous large-eddy
simulations of stable boundary layers that have strong dependence on grid
resolution, the simulated statistics obtained with the LASDD model show
relatively little resolution dependence for the range of grid sizes considered
here. In essence, we show that the new LASDD model is a robust subgrid-scale
parameterization for reliable, tuning-free simulations of stable boundary
layers, even with relatively coarse resolutions.


title:
A New Global Theory of the Earth's Dynamics : a Single Cause Can Explain
  All the Geophysical and Geological Phenomena

abstract:
  After describing all the contradictions associated with the current Plate
Tectonics theory, this paper proposes a model where a single cause can explain
all geophysical and geological phenomena. The source of the Earth's activity
lies in the difference of the angular velocities of the mantle and of the solid
inner core. The friction between both spheres infers heat, which is the cause
of the melted iron which constitutes most of the liquid outer core, as well as
the source of the global heat flow. The solid inner core angular velocity is
supposed to remain steady, while the mantle angular velocity depends on
gyroscopic forces (involving acceleration) and slowing down due to external
attractions and, principally the motions of mantle plates 2900 km thick. The
variations of the geomagnetic field are therefore the direct consequence of the
variations of the angular velocity of the mantle relative to that of the inner
core. As a result, the biological and tectonic evolutions during geological
times are due to those phenomena. So, the limits of eras coincide exactly with
the passage to zero of the geomagnetic field. Here we show that cycles of about
230-250 millions years, which exhibit the correlation between the mantle
angular velocity variations, the geomagnetic variations, and therefore the
climate, allow us to predict future events : the current global warming which
parallels the Earth's magnetic field decrease.


title: Laser-Induced Vibrational Frequency Shift

abstract:
  A mechanism is explored whereby intense laser radiation induces an optical
force between the constituent atoms of a molecule. In the case of a diatomic
molecule the effect results in a modification of the vibrational potential, and
using perturbation theory it is shown that this reduces the stretching
frequency. Model calculations on selected diatomics indicate that the extent of
the frequency shift should, under suitable conditions, be detectable by Raman
spectroscopy.


title: Testing a Crucial Assumption

abstract:
  Simplified description of an experiment of the Michelson-Morley type being
completed at the University of Western Australia with a discussion of the
possible meanings of its outcome.


title:
Skeletal Structures of the Ocean, Hypotheses and Interpretation of the
  Phenomenon

abstract:
  In this paper bringing up hypothesis about self-formation of an ocean
skeletal structures (OSS) assembled of fragments of a skeletal structures (SS)
of clouds when they fall dawn on an ocean surface (OS) in a result of a certain
atmospheric processes. It is given interpretation of an evidencing phenomenon
basing on the possibility of the surface tension forces action even on the OSS
blocks which are immersed in the sea. The capillary model of the observable
phenomenon (the OSS) is offered on the basis of which calculations of
durability and buoyancy of its separate blocks such as vertically floating
cylinders are carried out. Data on the nature observable OSS can be useful at
modelling many processes connected with Ocean.


title:
Studies of Nanotube Channeling for Efficient Beam Scraping at
  Accelerators

abstract:
  While particle beam steering (and in particular, "scraping") in accelerators
by bent channeling crystals is an established technique extensively tested at
IHEP Protvino and other major high-energy labs, an interesting question is how
one could improve channeling capabilities by applying modern nanotechnology.
Theoretical research of nanotube channeling was in progress over recent years.
In this work, we assess potential benefits from nanotube channeling for real
accelerator systems. We report simulation studies of channeling in
nanostructured material (carbon SWNT and MWNT) tested for possible serving as a
primary scraper for the collimation systems of hadron colliders. The advantages
of nanostructured material as a potential choice for a primary scraper in a
high-energy accelerator such as LHC or the Tevatron are discussed in comparison
to crystal lattices and amorphous material. We evaluate physical processes
relevant to this application and reveal nanotechnology requirements.


title: Inter-pattern speculation: beyond minority, majority and $-games

abstract:
  A new simple model of financial market is proposed, based on the sequential
and inter-temporal nature of trader-trader interaction, and on a new simple
trading strategy space. In this pattern-based speculation model, the traders
open and close their positions explicitly. Information ecology is strikingly
similar to that of the Minority Game which suggest to reinterpret the latter as
a model of synchronisation of predictability exploitation. Naive and
sophisticated agents are shown to give rise to very different phenomenology


title:
The origin of the Langevin equation and the calculation of the mean
  squared displacement: Let's set the record straight

abstract:
  Ornstein and his coauthors, who constructed a dynamical theory of Brownian
motion, taking the equation $mdv/dt =-\zeta v+X$ as their starting point,
usually named the equation after Einstein alone or after both Einstein and
Langevin; furthermore, Ornstein, who was the first to extract from this
equation the correct expression for $\bar{\Delta^2}$, the mean-squared distance
covered by a Brownian particle, credited de Haas-Lorentz, rather than Langevin,
for finding the stationary limit of $\bar{\Delta^2}$. A glance at Einstein's
1907 paper, titled ``Theoretical remarks on Brownian motion'', should suffice
to convince one that it is not unfair to attribute the {\it conception} of the
above equation, now universally known as the Langevin equation, to Einstein.
Langevin's avowed aim in his 1908 article was to recover, through a route that
was `infinitely more simple', Einstein's 1905 expression for the diffusion
coefficient, but a careful reading of Langevin's paper shows that--depending on
how one interprets his description of the statistical behavior of the random
force $X$ appearing in the above equation--his analysis is at best incomplete,
and at worst a mere tautology. Since textbook accounts are based on the
interpretation that renders the proof fallacious, alternative derivations,
which are adaptations of those given by de Haas-Lorentz and Ornstein, are
presented here. Some neglected aspects of the contents of Ornstein's early
papers on Brownian motion are also brought to light.


title: Einsteinian blunders

abstract:
  The World Year of Physics 2005 celebrates Einstein 1905. Too much celebration
of a single character may be hazardous as an example for the younger
generation. With such a motto in mind, I comment on some episodes in Einstein's
scientific career that are at some extent characterized by what could be dubbed
{\it blundering behavior}. The final purpose is obviously to {\it humanize} the
personage as opposed tore the current trend of {\it deification}.


title: The Leeson effect - Phase noise in quasilinear oscillators

abstract:
  Time, and equivalently frequency, is the most precisely measured physical
quantity. It is therefore inevitable that virtually all domains of engineering
and physics need reference oscillators. The oscillator noise can be decomposed
into amplitude noise and phase noise. The latter, far more important, affects
timing, for it is related to precision and accuracy of measurements.
  The oscillator, inherently, turns the phase noise of the internal parts into
frequency noise. This is a necessary consequence of the Barkhausen condition,
which states that the loop gain must be of one, with zero phase, for stationary
oscillation. There follows that oscillator phase noise, which is the integral
of the frequency noise, diverges in the long run. This is the Leeson effect.
  The topics covered can be divided into three parts. Chapter 1 addresses
language and general physical mechanisms. Chapter 2 aims at understanding the
inside of commercial oscillators through the analysis of the specifications.
Chapter 3 and 4 focus on the use of the Laplace transform to describe the
oscillator and its phase noise.
  Since spring 2004, I had the opportunity to give some seminars on noise in
oscillators at the Jet Propulsion Laboratory, at the IEEE Frequency Control
Symposium, at the FEMTO-ST Laboratory, and at the Universite' Henri Poincare'.
These seminars had the purpose to provide a TUTORIAL, as opposed to a report on
advanced science, addressed to a variety of people including technicians, PhD
students, and senior scientists. This booklet derives from these seminars, and
from numerous discussions with colleagues.


title: Sociophysics Simulations I: Language Competition

abstract:
  Using a bit-string model similar to biological simulations, the competition
between different languages is simulated both without and with spatial
structure. We compare our agent-based work with differential equations and the
competing bit-string model of Kosmidis et al.


title: Heavy atom tunneling in chemical reactions: study of H + LiF collisions

abstract:
  The H+LiF(X 1Sigma+,v=0-2,j=0)-->HF(X 1Sigma+,v',j')+Li(2S) bimolecular
process is investigated by means of quantum scattering calculations on the
chemically accurate X 2A' LiHF potential energy surface of Aguado et al. [J.
Chem. Phys. 119, 10088 (2003)]. Calculations have been performed for zero total
angular momentum for translational energies from 10-7 to 10-1 eV. Initial-state
selected reaction probabilities and cross sections are characterized by
resonances originating from the decay of metastable states of the H...F-Li and
Li...F-H van der Waals complexes. Extensive assignment of the resonances has
been carried out by performing quasibound states calculations in the entrance
and exit channel wells. Chemical reactivity is found to be significantly
enhanced by vibrational excitation at low temperatures, although reactivity
appears much less favorable than non-reactive processes due to the inefficient
tunneling of the relatively heavy fluorine atom strongly bound in van der Waals
complexes.


title: Quasi-planar steep water waves

abstract:
  A new description for highly nonlinear potential water waves is suggested,
where weak 3D effects are included as small corrections to exact 2D equations
written in conformal variables. Contrary to the traditional approach, a small
parameter in this theory is not the surface slope, but it is the ratio of a
typical wave length to a large transversal scale along the second horizontal
coordinate. A first-order correction for the Hamiltonian functional is
calculated, and the corresponding equations of motion are derived for steep
water waves over an arbitrary inhomogeneous quasi-1D bottom profile.


title:
Undoing static correlation: Long-range charge transfer in time-dependent
  density functional theory

abstract:
  Long-range charge transfer excited states are notoriously badly
underestimated in time-dependent density functional theory (TDDFT). We resolve
how {\it exact} TDDFT captures charge transfer between open-shell species: in
particular the role of the step in the ground-state potential, and the severe
frequency-dependence of the exchange-correlation kernel. An expression for the
latter is derived, that becomes exact in the limit that the charge-transfer
excitations are well-separated from other excitations. The exchange-correlation
kernel has the task of undoing the static correlation in the ground state
introduced by the step, in order to accurately recover the physical
charge-transfer states.


title: On the Disturbance Equation of Flow Instability

abstract:
  In this note, we propose a new idea by analyzing the basic disturbance
equations, and give starting equations for understanding the instability
phenomena of laminar flows and transition to turbulence. It is considered that
there is an interaction between the disturbance and the base flow in the
process of disturbance amplification. The transition to turbulence is the
result of this interaction. The linearity of the disturbance in linear theory
is oversimplified the problem. It is pointed out that the development of
disturbance is subjected to the influence of the base flow, and these effects
must be included in the governing equations of the disturbance.


title: Fine Grid Numerical Solutions of Triangular Cavity Flow

abstract:
  Numerical solutions of 2-D steady incompressible flow inside a triangular
cavity are presented. For the purpose of comparing our results with several
different triangular cavity studies with different triangle geometries, a
general triangle mapped onto a computational domain is considered. The
Navier-Stokes equations in general curvilinear coordinates in streamfunction
and vorticity formulation are numerically solved. Using a very fine grid mesh,
the triangular cavity flow is solved for high Reynolds numbers. The results are
compared with the numerical solutions found in the literature and also with
analytical solutions as well. Detailed results are presented.

categories: physics.flu-dyn cs.NA math.NA physics.comp-ph


title:
A Multifractal Detrended Fluctuation Description of Iranian Rial-US
  Dollar Exchange Rate

abstract:
  The miltifractal properties and scaling behaviour of the exchange rate
variations of the Iranian rial against the US dollar from a daily perspective
is numerically investigated. For this purpose the multifractal detrended
fluctuation analysis (MF-DFA) is used. Through multifractal analysis, the
scaling exponents, generalized Hurst exponents, generalized fractal dimensions
and singularity spectrum are derived. Moreover, contribution of two major
sources of multifractality, that is, fat-tailed probability distributions and
nonlinear temporal correlations are studied.


title:
Derivation of longitudinal Doppler shift equation between two moving
  bodies in a reference frame at rest using the particle property of photons

abstract:
  The equation of the Doppler shift of two bodies in inertial motion in a
reference frame at rest (i.e., stationary reference frame) is derived. In this
derivation, the wave-particle duality of photons in the theory of special
relativity is considered. The dilation of time of a moving clock, which is
derived from the Lorentz transformation that depends on the velocity of the
moving clock in the reference frame at rest, and wavefront counting by
geometrical drawing are used to describe the longitudinal Doppler shift. We
show that the equation of the Doppler shift depends on the velocities of the
two bodies in the reference frame at rest.


title:
An Iterative Procedure for the Estimation of Drift and Diffusion
  Coefficients of Langevin Processes

abstract:
  A general method is proposed which allows one to estimate drift and diffusion
coefficients of a stochastic process governed by a Langevin equation. It
extends a previously devised approach [R. Friedrich et al., Physics Letters A
271, 217 (2000)], which requires sufficiently high sampling rates. The analysis
is based on an iterative procedure minimizing the Kullback-Leibler distance
between measured and estimated two time joint probability distributions of the
process.


title: Is 'superstatistics' really 'super'?

abstract:
  Attention is drawn to problems associated with superstatistics, including the
apparent lack of knowledge of previous work in statistical physics displayed by
workers in this supposedly new field.


title: Ordinary Differential Equations through Dimensional Analysis

abstract:
  In in this paper we show how using D.A. it is found a simple change of
variables (c.v.) that brings us to obtain differential equations simpler than
the original one. In a pedagogical way (at least we try to do that) and in
order to make see that each c.v. corresponds to an invariant solution (induced
by a symmetry) or a particular solution, we compare (with all the tedious
details, i.e. calculations) the proposed method with the Lie method. The method
is checked even in ODEs that do not admit symmetries.


title:
Essential spectrum in vibrations of thin shells in membrane
  approximation. Propagation of singularities

abstract:
  The spectral problem of thin elastic shells in membrane approximation does
not satisfy the classical properties of compactness and so there exists an
essential spectrum. In the first part, we propose to determinate this spectrum
and the weakness directions in the shell. We particularly study the case of
homogeneous and isotropic shells with some examples. In the second part, we
consider an elementary model problem to study the propagation of singularities
and their reflections at the boundary of the domain. In the last, we study the
problem of propagation for an isotropic cylindrical shell and we show that the
equation of propagation does not depend on the Poisson coefficient.


title: BESII Detector Simulation

abstract:
  A Monte Carlo program based on Geant3 has been developed for BESII detector
simulation. The organization of the program is outlined, and the digitization
procedure for simulating the response of various sub-detectors is described.
Comparisons with data show that the performance of the program is generally
satisfactory.


title: It is about time to say "eureka!" in teaching physics

abstract:
  In the spirit of the International Year of Physics 2005 the author advices
the replacement of the teaching methods based on verbal explanations and to
perform a number of tasks following a given recipe by procedures that actively
involve the students in the physics discovery process.


title: Graphical aids for relativistic optics

abstract:
  The paper presents a relativistic space-time diagram, which displays in true
values the space (Cartesian and polar) and the time coordinates of the same
event detected from two inertial reference frames in relative motion related by
the Lorentz-Einstein transformations, the aberration angles and the Doppler
shifted periods and wavelengths. We use it in order to illustrate the
reflection of light on moving mirrors (horizontal and vertical) and the way in
which a single observer could measure the length of a moving rod. It displays
in true values the space-time coordinates of the same event generated by a
light signal.


title: Self-organizing social hierarchies on scale-free networks

abstract:
  In this work we extend the model of Bonabeau et al. in the case of scale-free
networks. A sharp transition is observed from an egalitarian to an hierarchical
society, with a very low population density threshold. The exact threshold
value also depends on the network size. We find that in an hierarchical society
the number of individuals with strong winning attitude is much lower than the
number of the community members that have a low winning probability.


title: Automated operation of a home made torque magnetometer using LabVIEW

abstract:
  In order to simplify and optimize the operation of our home made torque
magnetometer we created a new software system. The architecture is based on
parallel, independently running instrument handlers communicating with a main
control program. All programs are designed as command driven state machines
which greatly simplifies their maintenance and expansion. Moreover, as the main
program may receive commands not only from the user interface, but also from
other parallel running programs, an easy way of automation is achieved. A
program working through a text file containing a sequence of commands and
sending them to the main program suffices to automatically have the system
conduct a complex set of measurements. In this paper we describe the system's
architecture and its implementation in LabVIEW.


title:
Prediction oriented variant of financial log-periodicity and speculating
  about the stock market development until 2010

abstract:
  A phenomenon of the financial log-periodicity is discussed and the
characteristics that amplify its predictive potential are elaborated. The
principal one is self-similarity that obeys across all the time scales.
Furthermore the same preferred scaling factor appears to provide the most
consistent description of the market dynamics on all these scales both in the
bull as well as in the bear market phases and is common to all the major
markets. These ingredients set very desirable and useful constraints for
understanding the past market behavior as well as in designing forecasting
scenarios. One novel speculative example of a more detailed S$&$P500
development until 2010 is presented.


title:
Random matrix theory and robust covariance matrix estimation for
  financial data

abstract:
  The traditional class of elliptical distributions is extended to allow for
asymmetries. A completely robust dispersion matrix estimator (the `spectral
estimator') for the new class of `generalized elliptical distributions' is
presented. It is shown that the spectral estimator corresponds to an
M-estimator proposed by Tyler (1983) in the context of elliptical
distributions. Both the generalization of elliptical distributions and the
development of a robust dispersion matrix estimator are motivated by the
stylized facts of empirical finance. Random matrix theory is used for analyzing
the linear dependence structure of high-dimensional data. It is shown that the
Marcenko-Pastur law fails if the sample covariance matrix is considered as a
random matrix in the context of elliptically distributed and heavy tailed data.
But substituting the sample covariance matrix by the spectral estimator
resolves the problem and the Marcenko-Pastur law remains valid.


title: Relaxation to non-equilibrium in expanding ultracold neutral plasmas

abstract:
  We investigate the strongly correlated ion dynamics and the degree of
coupling achievable in the evolution of freely expanding ultracold neutral
plasmas. We demonstrate that the ionic Coulomb coupling parameter $\Gamma_{\rm
i}$ increases considerably in later stages of the expansion, reaching the
strongly coupled regime despite the well-known initial drop of $\Gamma_{\rm i}$
to order unity due to disorder-induced heating. Furthermore, we formulate a
suitable measure of correlation and show th at $\Gamma_{\rm i}$ calculated from
the ionic temperature and density reflects the degree of order in the system if
it is sufficiently close to a quasisteady state. At later times, however, the
expansion of the plasma cloud becomes faster than the relaxation of
correlations, and the system does not reach thermodynamic equilibrium anymore.


title:
Large Magnetic Moments of Arsenic-Doped Mn Clusters and their Relevance
  to Mn-Doped III-V Semiconductor Ferromagnetism

abstract:
  We report electronic and magnetic structure of arsenic-doped manganese
clusters from density-functional theory using generalized gradient
approximation for the exchange-correlation energy. We find that arsenic
stabilizes manganese clusters, though the ferromagnetic coupling between Mn
atoms are found only in Mn$_2$As and Mn$_4$As clusters with magnetic moments 9
$\mu_B$ and 17 $\mu_B$, respectively. For all other sizes, $x=$ 3, 5-10,
Mn$_x$As clusters show ferrimagnetic coupling. It is suggested that, if grown
during the low temperature MBE, the giant magnetic moments due to ferromagnetic
coupling in Mn$_2$As and Mn$_4$As clusters could play a role on the
ferromagnetism and on the variation observed in the Curie temperature of
Mn-doped III-V semiconductors.


title: Image transmission through a stable paraxial cavity

abstract:
  We study the transmission of a monochromatic "image" through a paraxial
cavity. Using the formalism of self-transform functions, we show that a
transverse degenerate cavity transmits the self-transform part of the image,
with respect to the field transformation over one round-trip of the cavity.
This formalism gives a new insight on the understanding of the behavior of a
transverse degenerate cavity, complementary to the transverse mode picture. An
experiment of image transmission through a hemiconfocal cavity show the
interest of this approach.


title:
Algebraic tools for dealing with the atomic shell model. I.
  Wavefunctions and integrals for hydrogen--like ions

abstract:
  Today, the 'hydrogen atom model' is known to play its role not only in
teaching the basic elements of quantum mechanics but also for building up
effective theories in atomic and molecular physics, quantum optics, plasma
physics, or even in the design of semiconductor devices. Therefore, the
analytical as well as numerical solutions of the hydrogen--like ions are
frequently required both, for analyzing experimental data and for carrying out
quite advanced theoretical studies. In order to support a fast and consistent
access to these (Coulomb--field) solutions, here we present the Dirac program
which has been developed originally for studying the properties and dynamical
behaviour of the (hydrogen--like) ions. In the present version, a set of Maple
procedures is provided for the Coulomb wave and Green's functions by applying
the (wave) equations from both, the nonrelativistic and relativistic theory.
Apart from the interactive access to these functions, moreover, a number of
radial integrals are also implemented in the Dirac program which may help the
user to construct transition amplitudes and cross sections as they occur
frequently in the theory of ion--atom and ion--photon collisions.


title: Low flicker-noise dc amplifier for 50 Ohm sources

abstract:
  This article analyzes the design of a low-noise amplifier intended as the
input front-end for the measurement of the low-frequency components (below 10
Hz) of a 50 Ohm source. Low residual flicker is the main desired performance.
This feature can only be appreciated if white noise is sufficiently low, and if
an appropriate design ensures dc stability. An optimal solution is proposed, in
which the low-noise and dc-stability features are achieved at a reasonable
complexity. Gain is accurate to more than 100 kHz, which makes the amplifier an
appealing external front-end for fast Fourier transform (FFT) analyzers.


title:
Geometric Finite Element Discretization of Maxwell Equations in Primal
  and Dual Spaces

abstract:
  Based on a geometric discretization scheme for Maxwell equations, we unveil a
mathematical\textit{\}transformation between the electric field intensity $E$
and the magnetic field intensity $H$, denoted as Galerkin duality. Using
Galerkin duality and discrete Hodge operators, we construct two system
matrices, $[ X_{E}] $ (primal formulation) and $[ X_{H} % ] $ (dual
formulation) respectively, that discretize the second-order vector wave
equations. We show that the primal formulation recovers the conventional
(edge-element) finite element method (FEM) and suggests a geometric foundation
for it. On the other hand, the dual formulation suggests a new (dual) type of
FEM. Although both formulations give identical dynamical physical solutions,
the dimensions of the null spaces are different.


title:
What shakes the FX tree? Understanding currency dominance, dependence
  and dynamics

abstract:
  There is intense interest in understanding the stochastic and dynamical
properties of the global Foreign Exchange (FX) market, whose daily transactions
exceed one trillion US dollars. This is a formidable task since the FX market
is characterized by a web of fluctuating exchange rates, with subtle
inter-dependencies which may change in time. In practice, traders talk of
particular currencies being 'in play' during a particular period of time -- yet
there is no established machinery for detecting such important information.
Here we apply the construction of Minimum Spanning Trees (MSTs) to the FX
market, and show that the MST can capture important features of the global FX
dynamics. Moreover, we show that the MST can help identify momentarily dominant
and dependent currencies.


title: Advanced bridge (interferometric) phase and amplitude noise measurements

abstract:
  The measurement of the close-to-the-carrier noise of rf and microwave devices
is a relevant issue in time and frequency metrology and in some fields of
electronics, physics and optics. While phase noise is the main concern,
amplitude noise is often of interest. The highest sensitivity is achieved with
the bridge (interferometric) method, which consists of the amplification and
synchronous detection of the noise sidebands after suppressing the carrier by
vector subtraction of an equal signal. A substantial progress in understanding
the flicker noise mechanism of the interferometer results in new schemes that
improve by 20--30 dB the sensitivity at low Fourier frequencies.
  The article provides the complete theory and detailed design criteria, and
reports on the implementation of a prototype. In real-time measurements, a
background noise of -175 -180 dBrad^2/Hz has been obtained at f=1 Hz off the
100 MHz carrier. Exploiting correlation and averaging in similar conditions,
the sensitivity exceeds -185 dBrad^2/Hz at f=1 Hz. A residual noise of -203
dBrad^2/Hz at f=250 Hz off the carrier has been obtained, while the ultimate
noise floor is still limited by the averaging capability of the correlator.
This is equivalent to a S/N ratio of 2E20 with a frequency spacing of 2.5E-6.
  Applications include the measurement of the properties of materials and the
observation of weak flicker-type physical phenomena, out of reach for other
instruments. We measured the flicker noise of a by-step attenuator (-171
dB[rad^2]/Hz at f=1 Hz) and of the ferrite noise of a reactive power divider
(-173.7 dB[rad^2]/Hz at f=1 Hz) without need of correlation.


title: Dynamical Minority Games in Futures Exchange Markets

abstract:
  We introduce the minority game theory for two kinds of the Korean treasury
bond (KTB) in Korean futures exchange markets. Since we discuss numerically the
standard deviation and the global efficiency for an arbitrary strategy, our
case is found to be approximate to the majority game. Our result presented will
be compared with numerical findings for the well-known minority and majority
game models.


title: Financial Networks in the Korean Stock Exchange Market

abstract:
  We investigate the financial network in the Korean stock exchange (KSE)
market, using both numerical simulations and scaling arguments. We estimate the
cross-correlation on the stock price exchanges of all companies listed on the
the Korean stock exchange market, where all companies are fully connected via
weighted links, by introducing a weighted random graph. The degree distribution
and the edge density are discussed numerically from the market graph, and the
statistical analysis for the degree distribution of vertices is particularly
found to approximately follow the power law.


title:
Strong-coupling effects in the relaxation dynamics of ultracold neutral
  plasmas

abstract:
  We describe a hybrid molecular dynamics approach for the description of
ultracold neutral plasmas, based on an adiabatic treatment of the electron gas
and a full molecular dynamics simulation of the ions, which allows us to follow
the long-time evolution of the plasma including the effect of the strongly
coupled ion motion. The plasma shows a rather complex relaxation behavior,
connected with temporal as well as spatial oscillations of the ion temperature.
Furthermore, additional laser cooling of the ions during the plasma evolution
drastically modifies the expansion dynamics, so that crystallization of the ion
component can occur in this nonequilibrium system, leading to lattice-like
structures or even long-range order resulting in concentric shells.


title:
The parabolic approximation of channeling and diffraction in bent
  crystals

abstract:
  The parabolic approximation is developed for high energy charged particles
scattering in a bent crystal with variable curvature. The general form of
parabolic equation is received for atomic chains located along coordinate axis
of orthogonal curvilinear coordinate system.


title: Relativistic Constraints on the Structure of Fundamental Forces

abstract:
  It is proved that Special Relativity imposes constraints on the structure of
fundamental forces. The orthogonality of the 4-force exerted on an elementary
particle and its 4-velocity is discussed. The significance of the
energy-momentum tensor associated with the field is analyzed. Relying on these
issues, it is proved that the Lorentz force is consistent with all constraints
whereas a force derived from a scalar potential does not satisfy all
requirements. This analysis explains a general discussion of Goldstein, Poole
and Safko.


title: Quantum Magnetohydrodynamics

abstract:
  The quantum hydrodynamic model for charged particle systems is extended to
the cases of non zero magnetic fields. In this way, quantum corrections to
magnetohydrodynamics are obtained starting from the quantum hydrodynamical
model with magnetic fields. The quantum magnetohydrodynamics model is analyzed
in the infinite conductivity limit. The conditions for equilibrium in ideal
quantum magnetohydrodynamics are established. Translationally invariant exact
equilibrium solutions are obtained in the case of the ideal quantum
magnetohydrodynamic model.