title: Gyroelectric cubic-quintic dissipative solitons

abstract:
  The influence of an externally applied magnetic field upon classic cubic
quintic dissipative solitons is investigated using both exact simulations and a
Lagrangian technique. The basic approach is to use a spatially inhomogeneous
magnetic field and to consider two important geometries, namely the Voigt and
the Faraday effects. A layered structure is selected for the Voigt case with
the principal aim being to demonstrate non-reciprocal behaviour for various
classes of spatial solitons that are known to exist as solutions of the complex
Ginzburg-Landau cubic-quintic envelope equation under dissipative conditions.
The system is viewed as dynamical and an opportunity is taken to display the
behaviour patterns of the spatial solitons in terms of two-dimensional
dynamical plots involving the total energy and the peak amplitude of the
spatial solitons. This action this leads to limit cycle plots that beautifully
reveal the behaviour of the solitons solutions at all points along the
propagation axis. The closed contour that exists in the absence of a magnetic
field is opened up and a limit point is exposed. The onset of chaos is revealed
in a dramatic way and it is clear that detailed control by the external
magnetic field can be exercised. The Lagrangian approach is adjusted to deal
with dissipative systems and through the choice of particular trial functions,
aspects of the dynamic behaviour of the spatial are predicted by this approach.
Finally, some vortex dynamics in the Faraday configuration are investigated.


title: The Weakness of the Scientific Assessments: A Praise of Silence

abstract:
  This article aims to show the weakness of the current scientific assessments,
based on a set of contradictory pseudo-axioms. The six pseudo-axioms are deeply
analysed. From the analysis are derived several conclusions. In spite of the
serious efforts of the scientists to establish a ranking of honors in order to
get funds or to control the academic and higher education institutions, the
Science doesn't exists in itself, but different kinds of knowledge. Therefore,
the scientists don't control the Science; they are mere experts in a field of
knowledge, which could be expressed in many valid ways. This variety determines
the existence of many models of academic curricula, based on heterogeneous ways
of valuation that change along the History.


title: Early out-of-equilibrium beam-plasma evolution

abstract:
  We solve analytically the out-of-equilibrium initial stage that follows the
injection of a radially finite electron beam into a plasma at rest and test it
against particle-in-cell simulations. For initial large beam edge gradients and
not too large beam radius, compared to the electron skin depth, the electron
beam is shown to evolve into a ring structure. For low enough transverse
temperatures, the filamentation instability eventually proceeds and saturates
when transverse isotropy is reached. The analysis accounts for the variety of
very recent experimental beam transverse observations.


title: A Study of the Water Cherenkov Calorimeter

abstract:
  The novel idea of water Cherenkov calorimeter made of water tanks as the next
generation neutrino detector for nu factories and nu beams is investigated. A
water tank prototype with a dimension of 1*1*13m^3 is constructed, its
performance is studied and compared with a GEANT4 based Monte Carlo simulation.
By using measured parameters of the water tank, including the light collection
efficiency, attenuation length, angular dependent response etc, a detailed
Monte Carlo simulation demonstrates that the detector performance is excellent
for identifying neutrino charged current events while rejecting neutral current
and wrong-flavor backgrounds.


title: The Application of Bayesian Technique for Particle Identification

abstract:
  The PID problem in high energy physics experiments is analysed with Bayesian
technique. The corresponding applicable method is presented.


title: A microscopic model of triangular arbitrage

abstract:
  We introduce a microscopic model which describes the dynamics of each dealer
in multiple foreign exchange markets, taking account of the triangular
arbitrage transaction. The model reproduces the interaction among the markets
well. We explore the relation between the parameters of the present microscopic
model and the spring constant of a macroscopic model that we proposed
previously.


title: Photon colliders: the first 25 years

abstract:
  In this invited talk at the ``historical'' session of PHOTON2005, I was asked
to recount the history and the development, from its earliest days to the
present, of the idea of photon colliders based on conversion of high energy
electrons to high-energy photons at a future high-energy linear e+e- collider.
Described in this talk are the general features and schemes of a photon
collider, the evolution in understanding of what the parameters of a realistic
photon collider are, possible solutions of various technical problems, the
physics motivation, and the present status of photon-collider development. For
a more detailed description of the photon collider at the ILC and a discussion
of the associated technical issues, please refer to my talks at PLC2005, the
conference that immediately followed PHOTON2005 (to be published in Acta
Physica Polonica B as well).


title:
Interplay between HIV/AIDS Epidemics and Demographic Structures Based on
  Sexual Contact Networks

abstract:
  In this article, we propose a network spread model for HIV epidemics, wherein
each individual is represented by a node of the transmission network and the
edges are the connections between individuals along which the infection may
spread. The sexual activity of each individual, measured by its degree, is not
homogeneous but obeys a power-law distribution. Due to the heterogeneity of
activity, the infection can persistently exist at a very low prevalence, which
has been observed in real data but can not be illuminated by previous models
with homogeneous mixing hypothesis. Furthermore, the model displays a clear
picture of hierarchical spread: In the early stage the infection is adhered to
these high-risk persons, and then, diffuses toward low-risk population. The
prediction results show that the development of epidemics can be roughly
categorized into three patterns for different countries, and the pattern of a
given country is mainly determined by the average sex-activity and transmission
probability per sexual partner. In most cases, the effect of HIV epidemics on
demographic structure is very small. However, for some extremely countries,
like Botswana, the number of sex-active people can be depressed to nearly a
half by AIDS.


title:
Nonlocality-controlled interaction of spatial solitons in nematic liquid
  crystals

abstract:
  We demonstrate experimentally that the interactions between a pair of
nonlocal spatial optical solitons in a nematic liquid crystal (NLC) can be
controlled by the degree of nonlocality. For a given beam width, the degree of
nonlocality can be modulated by varying the pretilt angle of NLC molecules via
the change of the bias. When the pretilt angle is smaller than pi/4, the
nonlocality is strong enough to guarantee the independence of the interactions
on the phase difference of the solitons. As the pretilt angle increases, the
degree of nonlocality decreases. When the degree is below its critical value,
the two solitons behavior in the way like their local counterpart: the two
in-phase solitons attract and the two out-of-phase solitons repulse.


title:
Turbulent thermal diffusion in a multi-fan turbulence generator with the
  imposed mean temperature gradient

abstract:
  We studied experimentally the effect of turbulent thermal diffusion in a
multi-fan turbulence generator which produces a nearly homogeneous and
isotropic flow with a small mean velocity. Using Particle Image Velocimetry and
Image Processing techniques we showed that in a turbulent flow with an imposed
mean vertical temperature gradient (stably stratified flow) particles
accumulate in the regions with the mean temperature minimum. These experiments
detected the effect of turbulent thermal diffusion in a multi-fan turbulence
generator for relatively high Reynolds numbers. The experimental results are in
compliance with the results of the previous experimental studies of turbulent
thermal diffusion in oscillating grids turbulence (Buchholz et al. 2004;
Eidelman et al. 2004). We demonstrated that turbulent thermal diffusion is an
universal phenomenon. It occurs independently of the method of turbulence
generation, and the qualitative behavior of particle spatial distribution in
these very different turbulent flows is similar. Competition between turbulent
fluxes caused by turbulent thermal diffusion and turbulent diffusion determines
the formation of particle inhomogeneities.


title: Hysteresis phenomenon in turbulent convection

abstract:
  Coherent large-scale circulations of turbulent thermal convection in air have
been studied experimentally in a rectangular box heated from below and cooled
from above using Particle Image Velocimetry. The hysteresis phenomenon in
turbulent convection was found by varying the temperature difference between
the bottom and the top walls of the chamber (the Rayleigh number was changed
within the range of $10^7 - 10^8$). The hysteresis loop comprises the one-cell
and two-cells flow patterns while the aspect ratio is kept constant ($A=2 -
2.23$). We found that the change of the sign of the degree of the anisotropy of
turbulence was accompanied by the change of the flow pattern. The developed
theory of coherent structures in turbulent convection (Elperin et al. 2002;
2005) is in agreement with the experimental observations. The observed coherent
structures are superimposed on a small-scale turbulent convection. The
redistribution of the turbulent heat flux plays a crucial role in the formation
of coherent large-scale circulations in turbulent convection.


title:
Space-charge transport limits of ion beams in periodic quadrupole
  focusing channels

abstract:
  It has been empirically observed in both experiments and particle-in-cell
simulations that space-charge-dominated beams suffer strong growth in
statistical phase-space area (degraded quality) and particle losses in
alternating gradient quadrupole transport channels when the undepressed phase
advance sigma_0 increases beyond about 85 degrees per lattice period. Although
this criterion has been used extensively in practical designs of strong
focusing intense beam transport lattices, the origin of the limit has not been
understood. We propose a mechanism for the transport limit resulting from
classes of halo particle resonances near the core of the beam that allow
near-edge particles to rapidly increase in oscillation amplitude when the
space-charge intensity and the flutter of the matched beam envelope are both
sufficiently large. When coupled with a diffuse beam edge and/or perturbations
internal to the beam core that can drive particles outside the edge, this
mechanism can result in large and rapid halo-driven increases in the
statistical phase-space area of the beam, lost particles, and degraded
transport. A core-particle model is applied to parametrically analyze this
process. Extensive self-consistent particle in cell simulations are employed to
better quantify space-charge limit and verify core-particle model predictions.


title: Diffusion-limited-aggregation on a directed small world network

abstract:
  For real world systems, nonuniform medium is ubiquitous. Therefore, we
investigate the diffusion-limited-aggregation process on a two dimensional
directed small-world network instead of regular lattice. The network structure
is established by rewiring connections on the two dimensional directed lattice.
Those rewired edges are controlled by two parameters $\theta$ and $m$, which
characterize the spatial length and the density of the long-range connections,
respectively. Simulations show that there exists a maximum value of the fractal
dimension when $\theta$ equals zero. Interestingly, we find that the symmetry
of the aggregation pattern is broken when rewired connections are long enough,
which may be an explanation for the formation of asymmetrical fractal in
nature. Then, we perform multifractal analysis on the patterns further.


title: Solar Wind Electric Fields in the Ion Cyclotron Frequency Range

abstract:
  Measurements of fluctuations of electric fields in the frequency range from a
fraction of one Hz to 12.5 Hz are presented, and corrected for the Lorentz
transformation of magnetic fluctuations to give the electric fields in the
plasma frame. The electric fields are large enough to provide the dominant
force on the ions of the solar wind in the region near the ion cyclotron
frequency of protons, larger than the force due to magnetic fluctuations. They
provide sufficient velocity space diffusion or heating to counteract
conservation of magnetic moment in the expanding solar wind to maintain nearly
isotropic velocity distributions.


title: A configuration system for the ATLAS trigger

abstract:
  The ATLAS detector at CERN's Large Hadron Collider will be exposed to
proton-proton collisions from beams crossing at 40 MHz that have to be reduced
to the few 100 Hz allowed by the storage systems. A three-level trigger system
has been designed to achieve this goal. We describe the configuration system
under construction for the ATLAS trigger chain. It provides the trigger system
with all the parameters required for decision taking and to record its history.
The same system configures the event reconstruction, Monte Carlo simulation and
data analysis, and provides tools for accessing and manipulating the
configuration data in all contexts.


title:
Control of Ultra-cold Inelastic Collisions by Feshbash Resonances and
  Quasi-One-Dimensional Confinement

abstract:
  Cold inelastic collisions of atoms or molecules are analyzed using very
general arguments. In free space, the deactivation rate can be enhanced or
suppressed together with the scattering length of the corresponding elastic
collision via a Feshbach resonance, and by interference of deactivation of the
closed and open channels. In reduced dimensional geometries, the deactivation
rate decreases with decreasing collision energy and does not increase with
resonant elastic scattering length. This has broad implications; e.g.,
stabilization of molecules in a strongly confining two-dimensional optical
lattice, since collisional decay of the highly vibrationally excited states due
to inelastic collisions is suppressed. The relation of our results with those
based on the Lieb-Liniger model are addressed.


title:
Generalized Permeability Function and Field Energy Density in Artificial
  Magnetics Using the Equivalent Circuit Method

abstract:
  The equivalent circuit model for artificial magnetic materials based on
various arrangements of split rings is generalized by taking into account
losses in the substrate or matrix material. It is shown that a modification is
needed to the known macroscopic permeability function in order to correctly
describe these materials. Depending on the dominating loss mechanism
(conductive losses in metal parts or dielectric losses in the substrate) the
permeability function has different forms. The proposed circuit model and
permeability function are experimentally validated. Furthermore, starting from
the generalized circuit model we derive an explicit expression for the
electromagnetic field energy density in artificial magnetic media. This
expression is valid at low frequencies and in the vicinity of the resonance
also when dispersion and losses in the material are strong. The presently
obtained results for the energy density are compared with the results obtained
using different methods.


title:
The Reasons of Line Broadening of Lattice Oscillations in Spectrum Small
  Frequencies of P-Chloronitrobenzene

abstract:
  Raman spectroscopies are carried out by the Method polarizable examinations
of the lattice oscillations of p-chloronitrobenzene at temperature 293 K. The
led matching of spectrums of p-chloronitrobenzene with p-bromochlorobenzene and
p-dibromobenzene has shown that the significant line broadening in
p-chloronitrobenzene is caused not only clutter in allocation of molecules
concerning parasubstitution benzol. It is necessary to consider also and
clutter in rotational displacements of the nitro of group concerning a plane of
a molecule. Calculations of frequency spectra were led on a method the Dyne.


title:
Analytical model of the enhanced light transmission through
  subwavelength metal slits: Green's function formalism versus Rayleigh's
  expansion

abstract:
  We present an analytical model of the resonantly enhanced transmission of
light through a subwavelength nm-size slit in a thick metal film. The simple
formulae for the transmitted electromagnetic fields and the transmission
coefficient are derived by using the narrow-slit approximation and the Green's
function formalism for the solution of Maxwell's equations. The resonance
wavelengths are in agreement with the semi-analytical model [Y. Takakura, Phys.
Rev. Lett. 86, 5601 (2001)], which solves the wave equations by using the
Rayleigh field expansion. Our formulae, however, show great resonant
enhancement of a transmitted wave, while the Rayleigh expansion model predicts
attenuation. The difference is attributed to the near-field subwavelength
diffraction, which is not considered by the Rayleigh-like expansion models.


title: MELENCOLIA I: The physics of Albrecht Duerer

abstract:
  Duerer's engraving ``MELENCOLIA I'' was circulated in two versions not
previously distinguished. Besides their conspicuous early Renaissance
scientific instruments and tools, they contain numerous apparently unreported
concealments whose detection reveals heresies expressed in the work. The main
one is encoded in the motto {\em MELENCOLIA I} itself: Natural Philosophy, not
Mathematical Philosophy or Theological Philosophy, is the way to knowledge.
Unusual optical illusions and subliminal images, differing between the two
versions, declare the relativity and ambiguity of perception, and indicate that
the work was a Humanist document intended for a Humanist viewership.


title: Chasing 'Slow Light'

abstract:
  A critical review of experimental studies of the so-called 'slow light'
arising due to anomalously high steepness of the refractive index dispersion
under conditions of electromagnetically induced transparency or coherent
population oscillations is presented. It is shown that a considerable amount of
experimental evidence for observation of the 'slow light' is not related to the
low group velocity of light and can be easily interpreted in terms of a
standard model of interaction of light with a saturable absorber.


title:
Exploring Harmony between Theory and Computation - Toward a unified
  electronic structure theory

abstract:
  The physical aspect of a general perturbation theory is explored. Its role as
a physical principle for understanding the interaction among matter with
different levels of hierarchy is appreciated. It is shown that the generic
perturbation theory can not only be used for understanding various electronic
phenomena including the nature of chemical bonds but also serve as a
$\it{unified}$ theme for developing $\it{general}$ electronic structure
theories and calculation schemes. In particular, a $\it{standard}$ electron
correlation approach is suggested and established according to this law.


title:
Amplification and Scintillation Properties of Oxygen-Rich Gas Mixtures
  for Optical-TPC Applications

abstract:
  We studied electron amplification and light emission from avalanches in
oxygen-containing gas mixtures. The mixtures investigated in this work
included, among others, CO2 and N2O mixed with Triethylamine (TEA) or N2.
Double-Step Parallel Gap (DSPG) multipliers and THick Gas Electron Multipliers
(THGEM) were investigated. High light yields were measured from CO2+N2 and
CO2+TEA, though with different emission spectra. We observed the characteristic
wave-length emission of N2 and of TEA and used a polymer wave-length shifter to
convert TEA UV-light into the visible spectrum. The results of these
measurements indicate the applicability of optical recording of ionizing tracks
in a TPC target-detector designed to study the cross section of the 16O(g,a)12C
reaction, a central problem in nuclear astrophysics.

categories: physics.ins-det astro-ph nucl-ex nucl-th


title:
Polarization dependent photoionization cross-sections and radiative
  lifetimes of atomic states in Ba

abstract:
  The photoionization cross-sections of two even-parity excited states, $5d6d
^3D_1$ and $6s7d ^3D_{2}$, of atomic Ba at the ionization-laser wavelength of
556.6 nm were measured. We found that the total cross-section depends on the
relative polarization of the atoms and the ionization-laser light. With
density-matrix algebra, we show that, in general, there are at most three
parameters in the photoionization cross-section. Some of these parameters are
determined in this work. We also present the measurement of the radiative
lifetime of five even-parity excited states of barium.


title:
Enhanced Transmission of Light and Matter through Nanoapertures without
  Assistance of Surface Waves

abstract:
  Subwavelength aperture arrays in thin metal films enable enhanced
transmission of light and matter waves [for example, see T.W. Ebbesen et al.,
Nature (London) 391, 667 (1998) and E. Moreno et al., Phys. Rev. Lett. 95,
170406 (2005)]. The phenomenon relies on resonant excitation of the surface
electron or matter waves. We show another mechanism that provides a great
transmission enhancement not by coupling to the surface waves but by the
interference of diffracted evanescent waves in the far-field zone. Verification
of the mechanism is presented by comparison with recently published data.


title:
Fine-grained Delaunay triangulation in a simulation of tumor spheroid
  growth

abstract:
  The simulation of many-particle systems often requires the detailed knowledge
of proximity relations to reduce computational complexity and to provide a
basis for specific calculations. Here we describe the basic scheme of a
simulator of tumor spheroid growth: the calculation of mechanical interactions
between cells and of the concentrations of diffusing chemicals requires a
backbone provided by the Delaunay triangulation and the volumes of the
associated Voronoi regions. Thus the Delaunay triangulation provides both the
proximity relations needed to reduce the computational complexity and the basic
structures that are needed to carry out the calculation of the biochemical
interactions between cells and with the enviroment. A 3D version of the
simulator uses the CGAL library as an essential component for the efficient
computation of the Delaunay triangulation and of the Voronoi regions.


title: Functional dissipation microarrays for classification

abstract:
  In this article, we describe a new method of extracting information from
signals, called functional dissipation, that proves to be very effective for
enhancing classification of high resolution, texture-rich data. Our algorithm
bypasses to some extent the need to have very specialized feature extraction
techniques, and can potentially be used as an intermediate, feature enhancement
step in any classification scheme.
  Functional dissipation is based on signal transforms, but uses the transforms
recursively to uncover new features. We generate a variety of masking functions
and `extract' features with several generalized matching pursuit iterations. In
each iteration, the recursive process modifies several coefficients of the
transformed signal with the largest absolute values according to the specific
masking function; in this way the greedy pursuit is turned into a slow,
controlled, dissipation of the structure of the signal that, for some masking
functions, enhances separation among classes.
  Our case study in this paper is the classification of crystallization
patterns of amino acids solutions affected by the addition of small quantities
of proteins.


title:
Dynamic Pattern of Finite-Pulsed Beams inside One-dimensional Photonic
  Band Gap Materials

abstract:
  The dynamics of two-dimensional electromagnetic (EM) pulses through
one-dimensional photonic crystals (1DPC) has been theoretically studied.
Employing the time expectation integral over the Poynting vector as the arrival
time [Phys. Rev. Lett. 84, 2370, (2000)], we show that the superluminal
tunneling process of EM pulses is the propagation of the net forward-going
Poynting vector through the 1DPC, and the Hartman effect is due to the
saturation effect of the arrival time (smaller and smaller time accumulated) of
the net forward energy flow caused by the interference effect of the forward
and the backward field (from the interfaces of each layer) happened in the
region before the 1DPC and in the front part of the 1DPC.


title:
Noise figure and photon probability distribution in Coherent Anti-Stokes
  Raman Scattering (CARS)

abstract:
  The noise figure and photon probability distribution are calculated for
coherent anti-Stokes Raman scattering (CARS) where an anti-Stokes signal is
converted to Stokes. We find that the minimum noise figure is ~ 3dB.


title: Reciprocity and the Emergence of Power Laws in Social Networks

abstract:
  Research in network science has shown that many naturally occurring and
technologically constructed networks are scale free, that means a power law
degree distribution emerges from a growth model in which each new node attaches
to the existing network with a probability proportional to its number of links
(=degree). Little is known about whether the same principles of local
attachment and global properties apply to societies as well. Empirical evidence
from six ethnographic case studies shows that complex social networks have
significantly lower scaling exponents gamma ~ 1 than have been assumed in the
past. Apparently humans do not only look for the most prominent players to play
with. Moreover cooperation in humans is characterized through reciprocity, the
tendency to give to those from whom one has received in the past. Both
variables -- reciprocity and the scaling exponent -- are negatively correlated
($r=-0.767, sig=0.075$). If we include this effect in simulations of growing
networks, degree distributions emerge that are much closer to those empirically
observed. While the proportion of nodes with small degrees decreases
drastically as we introduce reciprocity, the scaling exponent is more robust
and changes only when a relatively large proportion of attachment decisions
follow this rule. If social networks are less scale free than previously
assumed this has far reaching implications for policy makers, public health
programs and marketing alike.


title: A versatile electrostatic trap

abstract:
  A four electrode electrostatic trap geometry is demonstrated that can be used
to combine a dipole, quadrupole and hexapole field. A cold packet of 15ND3
molecules is confined in both a purely quadrupolar and hexapolar trapping field
and additionally, a dipole field is added to a hexapole field to create either
a double-well or a donut-shaped trapping field. The profile of the 15ND3 packet
in each of these four trapping potentials is measured, and the dependence of
the well-separation and barrier height of the double-well and donut potential
on the hexapole and dipole term are discussed.


title: Emergence of cooperation induced by preferential learning

abstract:
  The evolutionary Prisoner's Dilemma Game (PDG) and the Snowdrift Game (SG)
with preferential learning mechanism are studied in the Barab\'asi-Albert
network. Simulation results demonstrate that the preferential learning of
individuals remarkably promotes the cooperative behavior for both two games
over a wide range of payoffs. To understand the effect of preferential learning
on the evolution of the systems, we investigate the time series of the
cooperator density for different preferential strength and payoffs. It is found
that in some specific cases two games both show the $1/f$-scaling behaviors,
which indicate the existence of long range correlation. We also figure out that
when the large degree nodes have high probability to be selected, the PDG
displays a punctuated equilibrium-type behavior. On the contrary, the SG
exhibits a sudden increase feature. These temporary instable behaviors are
ascribed to the strategy shift of the large degree nodes.


title: High-speed Laser Micromachining with Copper Bromide Laser

abstract:
  The application of the copper bromide (CuBr) laser as an attractive tool in
the micro-machining of different materials has been demonstrated. High-quality
drilling by trepanning and precision cutting was established on several
materials with a negligible heat-affected zone (HAZ). That good performance was
a result of the combination of high power visible radiation, short pulses, and
close to the diffraction-limited laser beam quality with high-speed galvo
scanner beam steering.


title: Niederhauser's model for epilepsy and wavelet methods

abstract:
  Wavelets and wavelet transforms (WT) could be a very useful tool to analyze
electroencephalogram (EEG) signals. To illustrate the WT method we make use of
a simple electric circuit model introduced by Niederhauser, which is used to
produce EEG-like signals, particularly during an epileptic seizure. The
original model is modified to resemble the 10-20 derivation of the EEG
measurements. WT is used to study the main features of these signals


title:
Effect of pressure on the phase behavior and structure of water confined
  between nanoscale hydrophobic and hydrophilic plates

abstract:
  We perform systematic molecular dynamics simulations of water confined
between two nanoscale plates at T=300 K. We investigate the effect of pressure
(-0.15 GPa <= P <= 0.2 GPa) and plate separation (0.4 nm <= d <= 1.6 nm) on the
phase behavior of water when the plates are either hydrophobic or hydrophilic.
When water is confined between hydrophobic plates, capillary evaporation occurs
between the plates at low enough P. The threshold value of d at which this
transition occurs decreases with P (e.g., 1.6 nm at P ~ -0.05 GPa; 0.5 nm at P
\~ 0.1 GPa), until, at high P, no capillary evaporation occurs. For d ~ 0.6 nm
and P >= 0.1 GPa, the system crystallizes into a bilayer ice.
  A P-d phase diagram showing the vapor, liquid, and bilayer ice phases is
proposed. When water is confined by hydrophilic (hydroxylated silica) plates,
it remains in the liquid phase at all P and d studied. Interestingly, we
observe, for this case, that even at the P at which bulk water cavitates, the
confined water remains in the liquid state. We also study systematically the
state of hydration at different P for both kinds of plates. For the range of
conditions studied here, we find that in the presence of hydrophobic plates the
effect of P is to enhance water structure and to push water molecules toward
the plates. The average orientation of water molecules next to the hydrophobic
plates does not change upon pressurization. In contrast, in the presence of
hydrophilic plates, water structure is insensitive to P. Hence, our results
suggest that upon pressurization, hydrophobic plates behave as `soft' surfaces
(in the sense of accommodating pressure-dependent changes in water structure)
while hydrophilic walls behave as `hard' surfaces.


title: Hyper-Hamiltonian quantum mechanics

abstract:
  We present a modification of quantum mechanics with a *possible worlds*
semantics. It is shown that `gauge' degrees of freedom along possible worlds
can be used to encode gravitational information.


title: The Process of price formation and the skewness of asset returns

abstract:
  Distributions of assets returns exhibit a slight skewness. In this note we
show that our model of endogenous price formation \cite{Reimann2006} creates an
asymmetric return distribution if the price dynamics are a process in which
consecutive trading periods are dependent from each other in the sense that
opening prices equal closing prices of the former trading period. The
corresponding parameter $\alpha$ is estimated from daily prices from 01/01/1999
- 12/31/2004 for 9 large indices. For the S&P 500, the skewness distribution of
all its constituting assets is also calculated. The skewness distribution due
to our model is compared with the distribution of the empirical skewness values
of the ingle assets.


title: Stock mechanics: unification with economy

abstract:
  Associating stock mechanics to real economy, in terms of volume, number of
transactions, and cost, i.e. money flow for shares, we obtained the fundamental
laws of stock mechanics.


title: Mass hierarchies from two extra dimensions

abstract:
  The string, MSSM GUT, weak and QCD scales, and the Rydberg constant,
correspond to the positions of AdS domain wall intersections in a
two-dimensional extra space of infinite extent. The domain walls lie along and
parallel to the sides of cells which tile the extra space. The cells are
four-sided with parallel opposite sides of lengths Rln(pi/2) and Rln(pi), where
R is the AdS radius of curvature. Particle masses correspond to the positions
of domain walls. We represent the extra space graphically.


title:
Lorentz Transformation as a 'Complementary Time-Dependent Coordinate
  Transformation'. The Physical Foundation of Einstein' Special Relativity

abstract:
  We here deduce Lorentz transformation (LT) as a member of a class of
time-dependent coordinate transformations, complementary to those already known
as spatial translations and rotations. This exercise validates the principle of
physical determination of equations within special relativity theory (SRT), in
accordance with the derivation of the LT in Einstein's original paper on
relativity. This validation is possible because our LT deduction also discloses
the real physics warranting Einstein's manipulations of several equations in
that paper, thus proving the correctness of his derivation of the LT. The
essential role of the revelation in the act of science then results. Far from
being an arbitrary dogmatic construction, SRT appears to be a revealed dogmatic
theory that can be turned into a truly physical one like operational theory.
Radically new technological applications of relativistic quantum theory then
results.


title:
The Differential Geometry and Physical Basis for the Applications of
  Feynman Diagrams

abstract:
  This paper recalls the development of gauge theory culminating in Yang-Mills
theory, and the application of differential geometry including connections on
fiber bundles to field theory. Finally, we see how the preceding is used to
explain the Feynman diagrams appearing on the Feynman postage stamp released in
May 2005. Version 2 included the Feynman diagrams, Version 3 corrected typos
and Version 4 included an appendix for the derivation of the Yang-Mills
transformation and field strength. Version 5 indicates that the article has
been published in the Notices of the AMS and in July 2009 appears in Chinese
translation in a journal of the Chinese Academy of Sciences. It also corrects
some typos and adds to the appendix a heuristic derivation of the Yang-Mills
field strength.


title:
Absoluteness of Velocity Produced by Accelerating Process and Absolute
  Space-time Theory with Variable Scales

abstract:
  It is proved by means of the dynamical effects of special relativity that
velocity caused by accelerating process is not a relative concept. The
influence of accelerating process should be considered in space-time theory.
Besides the Newtonian absolute space-time theory with invariable space-time
scales and the Einstein relative space-time theory with variable space-time
scales, there exists the third space-time theory, i.e., the absolute space-time
theory with variable space-time scales. At present, special relativity is
divided into two parts, kinematics and dynamics. In kinematics, force and
acceleration are not considered so that space and time becomes relative
concepts. This division is completely artificial and irrational. The rational
space-time theory should be established on the foundation of dynamics
consistently. The changing rules of space, time and mass with speed should be
dependent of accelerating processes and with absolute significance. The real
meaning of invariability principle of high speed should be that we can not make
the speed of an object speed with rest mass reach and exceed the speed of light
in vacuum by the method of accelerating object. It is proved that the
absolutely resting reference frame exists. In order to eliminate multifarious
space-time paradoxes in special relativity, and coincide with Big-bang
cosmology, the absolutely resting frame is necessary. A method is put forward
to look for the absolutely resting reference frame. The isotropy reference
frame of cosmic microwave background radiation can be regarded as the
absolutely resting reference frame actually at present.


title: Multipole vector solitons in nonlocal nonlinear media

abstract:
  We show that multipole solitons can be made stable via vectorial coupling in
bulk nonlocal nonlinear media. Such vector solitons are composed of mutually
incoherent nodeless and multipole components jointly inducing a nonlinear
refractive index profile. We found that stabilization of the otherwise highly
unstable multipoles occurs below a maximum energy flow. Such threshold is
determined by the nonlocality degree.


title: Self-image effects for diffraction and dispersion

abstract:
  Excerpt: We apply the wavelet transform to the fractal Talbot effect in both
diffraction and fiber dispersion. In the first case, the self similar character
of the transverse paraxial field at irrational multiples of the Talbot distance
is confirmed, whereas in the second case it is shown that the field is not self
similar for supergaussian pulses. Finally, a high-precision measurement of
irrational distances employing the fractal index determined with the wavelet
transform is pointed out


title:
Optical control of spin coherence in singly charged (In,Ga)As/GaAs
  quantum dots

abstract:
  Electron spin coherence has been generated optically in n-type modulation
doped (In,Ga)As/GaAs quantum dots (QDs) which contain on average a single
electron per dot. The coherence arises from resonant excitation of the QDs by
circularly-polarized laser pulses, creating a coherent superposition of an
electron and a trion state. Time dependent Faraday rotation is used to probe
the spin precession of the optically oriented electrons about a transverse
magnetic field. Spin coherence generation can be controlled by pulse intensity,
being most efficient for (2n+1)pi-pulses.


title:
Radiative corrections to the magnetic-dipole transition amplitude in
  B-like ions

abstract:
  The one-electron quantum-electrodynamic corrections to the magnetic-dipole
transition amplitude between the fine-structure levels (1s^2 2s^2 2p) ^2P_3/2 -
^2P_1/2 in boronlike ions are calculated to all orders in (\alpha Z). The
results obtained serve for improving the theoretical accuracy of the lifetime
of the (1s^2 2s^2 2p) ^2P_3/2 level in boronlike argon.


title:
Study of a nonhomogeneous aerogel radiator in a proximity focusing RICH
  detector

abstract:
  The use of a nonhomogeneous aerogel radiator, i.e. one consisting of layers
with different refractive indices, has been shown to improve the resolution of
the Cherenkov angle measured with a proximity focusing RICH detector. In order
to obtain further information on the performance of such a detector, a simple
model has been used to calculate the resolution and search for optimal radiator
parameters.


title:
Nonequilibrium phase transition in the coevolution of networks and
  opinions

abstract:
  Models of the convergence of opinion in social systems have been the subject
of a considerable amount of recent attention in the physics literature. These
models divide into two classes, those in which individuals form their beliefs
based on the opinions of their neighbors in a social network of personal
acquaintances, and those in which, conversely, network connections form between
individuals of similar beliefs. While both of these processes can give rise to
realistic levels of agreement between acquaintances, practical experience
suggests that opinion formation in the real world is not a result of one
process or the other, but a combination of the two. Here we present a simple
model of this combination, with a single parameter controlling the balance of
the two processes. We find that the model undergoes a continuous phase
transition as this parameter is varied, from a regime in which opinions are
arbitrarily diverse to one in which most individuals hold the same opinion. We
characterize the static and dynamical properties of this transition.

categories: physics.soc-ph cond-mat.dis-nn physics.data-an q-bio.PE


title:
Applying Free Random Variables to Random Matrix Analysis of Financial
  Data. Part I: A Gaussian Case

abstract:
  We apply the concept of free random variables to doubly correlated (Gaussian)
Wishart random matrix models, appearing for example in a multivariate analysis
of financial time series, and displaying both inter-asset cross-covariances and
temporal auto-covariances. We give a comprehensive introduction to the rich
financial reality behind such models. We explain in an elementary way the main
techniques of the free random variables calculus, with a view to promote them
in the quantitative finance community. We apply our findings to tackle several
financially relevant problems, such as of an universe of assets displaying
exponentially decaying temporal covariances, or the exponentially weighted
moving average, both with an arbitrary structure of cross-covariances.

categories: physics.soc-ph cond-mat.stat-mech math-ph math.MP


title: Visual Saliency and Attention as Random Walks on Complex Networks

abstract:
  The current article shows how concepts from the areas of random walks, Markov
chains, complex networks and image analysis can be naturally combined in order
to provide a unified and biologically plausible model relating saliency and
visual attention. Two types of models are proposed: (i) images are converted
into complex networks by considering pixels as nodes while connections are
established in terms of fields of influence defined by visual features such as
tangent fields induced by gray-level contrasts and distance; and (ii) image
pixels exhibiting particularly distinctive values of visual properties such as
gray-level intensity, contrast, size of objects, orientation and texture are
mapped into nodes and the weights of links are defined in order to favor
transitions between regions with similar or different visual features, also
taking the distance between the nodes into account. Preferential random walks
are performed on such networks in order to emulate attentional shifts and eye
movements, and the saliency of each region is obtained in terms of the
frequency of visits to each node at equilibrium. In the case of the first
model, there is a definite tendency to emphasize not only high curvature points
but also convergences of the tangent field. The frequency of visits is found to
be strongly correlated with the node degrees (strengths) for this model.
Different results have been obtained for the second model as a consequence of
the directed and asymmetric nature of the respectively obtained networks.


title: Elements, topology, and T-shirts

abstract:
  Consider the network of elements connected by adjacency in atomic number and
periodic table column. If all elements except H-He are connected by identical
springs and constrained to a z-spiral in 2D, a map sans spring-crossing results
for various values of rest length in units of the H-He distance. If the
z-spiral is removed, and the network allowed to relax in 3D, the resulting
surface with three holes has the topology of a T-shirt or open-handle teapot.
Mapping this to a shirt's front-back pattern yields a 2D table of elemental
inter-connects in tabular (nearly rectilinear) form. Sample applications: The
flat spiral (like other spiral patterns) might serve as basis for an
educational board game, while the T-shirt table might serve as a starting point
for ``topologically informed'' classroom periodic-table design projects with
wearable awards.


title: Special Relativity is an Excellent Theory

abstract:
  Criteria for defining errors of a physical theory are formulated. It is shown
that the Special Theory of Relativity (STR) has a solid mathematical basis. An
enormous amount of experiments carried out in particle physics use beams of
particles having a very high energy. The data of these experiments are
consistent with STR and support our confidence that STR is an excellent theory.
Several specific cases of this issue are discussed explicitly. Contrary to a
common belief, it is proved that the contemporary mainstream of physicists
adhere to some theoretical ideas that violate STR.


title:
Age-related alterations of relaxation processes and non-Markov effects
  in stochastic dynamics of R-R intervals variability from human ECGs

abstract:
  In this paper we consider the age-related alterations of heart rate
variability on the basis of the study of non-Markovian effects. The age
dynamics of relaxation processes is quantitatively described by means of local
relaxation parameters, calculated by the specific localization procedure. We
offer a quantitative informational measure of non-Markovity to evaluate the
change of statistical effects of memory. Local relaxation parameters for young
and elderly people differ by 3.3 times, and quantitative measures of
non-Markovity differ by 4.2 times. The comparison of quantitative parameters
allows to draw conclusions about the reduction of relaxation rate with ageing
and the higher degree of the Markovity of heart rate variability of elderly
people.


title:
On the characteristic form of histograms appearing at the culmination of
  solar eclipse

abstract:
  As shown in a number of our works, the form of histograms - distributions of
amplitude fluctuations - varies regularly in time, with these variations being
similar for processes of any nature, from biochemical reactions to noise in the
gravitational antenna and all types of the radioactive decay. In particular, we
have revealed basic laws, suggesting a cosmo-physical nature of these
phenomena, in the time series created by the noise generators of the global GCP
net. On the basis of all the results obtained, a conclusion has been made that
the histogram form is determined by fluctuations of the spacetime, which depend
on the movement of the measured system (laboratory) relative to the heavenly
bodies. An important step to understand the nature of these phenomena was the
finding that at the moments of the new Moon, a specific histogram form appears
practically simultaneously at different geographical points, from Arctic to
Antarctic, in middle latitudes of West and East hemispheres. This effect seems
to be not due to a change of the tide-generating forces; to explain it,
nontrivial hypotheses are needed. The present paper shows the appearance of
specific histogram forms at the culminations of the solar eclipses (moments of
the geocentric superposition of the Sun and the Moon), with the eclipse forms
differing from the new-moon ones. Specific histogram forms appear practically
simultaneously all over the Earth and depend nor on the geographical
coordinates, nor on the nature of the process studied.


title:
Regular and stochastic behavior of Parkinsonian pathological tremor
  signals

abstract:
  Regular and stochastic behavior in the time series of Parkinsonian
pathological tremor velocity is studied on the basis of the statistical theory
of discrete non-Markov stochastic processes and flicker-noise spectroscopy. We
have developed a new method of analyzing and diagnosing Parkinson's disease
(PD) by taking into consideration discreteness, fluctuations, long- and
short-range correlations, regular and stochastic behavior, Markov and
non-Markov effects and dynamic alternation of relaxation modes in the initial
time signals. The spectrum of the statistical non-Markovity parameter reflects
Markovity and non-Markovity in the initial time series of tremor. The
relaxation and kinetic parameters used in the method allow us to estimate the
relaxation scales of diverse scenarios of the time signals produced by the
patient in various dynamic states. The local time behavior of the initial time
correlation function and the first point of the non-Markovity parameter give
detailed information about the variation of pathological tremor in the local
regions of the time series. The obtained results can be used to find the most
effective method of reducing or suppressing pathological tremor in each
individual case of a PD patient. Generally, the method allows one to assess the
efficacy of the medical treatment for a group of PD patients.


title: On the vacancy decay in endohedral atoms

abstract:
  It is demonstrated that the fullerene shell affects dramatically the
radiative and Auger vacancy decay of an endohedral atom A@C60. The
collectivized electrons of the C60 shell add new possibilities for radiative
and non-radiative decays similar to that in ordinary atoms where initial and
final state vacancies almost always belong to different subshells.
  It is shown that the smallness of the atomic shell radii as compared to that
of the fullerenes shell provides an opportunity to derive the simple formulas
for the probabilities of the electron transitions. It is shown that the
radiative and Auger (or Koster-Kronig) widths of a vacancy decay due to
electron transition in the atom A in A@C60 acquire an additional factors that
can be expressed via the polarizability of the C60 at transition energy.
  It is demonstrated that due to opening of the non-radiative decay channel for
vacancies in subvalent subshells the decay probability increases by five -- six
orders of magnitude.


title:
Manifestation of Chaos in Real Complex Systems: Case of Parkinson's
  Disease

abstract:
  In this chapter we present a new approach to the study of manifestations of
chaos in real complex system. Recently we have achieved the following result.
In real complex systems the informational measure of chaotic chatacter (IMC)
can serve as a reliable quantitative estimation of the state of a complex
system and help to estimate the deviation of this state from its normal
condition. As the IMC we suggest the statistical spectrum of the non-Markovity
parameter (NMP) and its frequency behavior. Our preliminary studies of real
complex systems in cardiology, neurophysiology and seismology have shown that
the NMP has diverse frequency dependence. It testifies to the competition
between Markovian and non-Markovian, random and regular processes and makes a
crossover from one relaxation scenario to the other possible. On this basis we
can formulate the new concept in the study of the manifestation of chaoticity.
We suggest the statistical theory of discrete non-Markov stochastic processes
to calculate the NMP and the quantitative evaluation of the IMC in real complex
systems. With the help of the IMC we have found out the evident manifestation
of chaosity in a normal (healthy) state of the studied system, its sharp
reduction in the period of crises, catastrophes and various human diseases. It
means that one can appreciably improve the state of a patient (of any system)
by increasing the IMC of the studied live system. The given observation creates
a reliable basis for predicting crises and catastrophes, as well as for
diagnosing and treating various human diseases, Parkinson's disease in
particular.


title: Algebraic Derivation of the Schwarzschild Time Dilation Function

abstract:
  Using only a thought experiment and Einstein's correspondence principal, a
model is derived that correctly predicts the Schwarzschild time dilation
expression in limiting cases. The method requires almost no prerequisite
knowledge from the student and is carried out with only algebraic techniques,
allowing the introduction of a mathematical example of general relativity to
introductory physics students.


title: Stray Field Magnetic Resonance Tomography using Ferromagnetic Spheres

abstract:
  The methodology for obtaining two- and three-dimensional magnetic resonance
images by using azimuthally symmetric dipolar magnetic fields from
ferromagnetic spheres is described. We utilize the symmetric property of a
geometric sphere in the presence of a large externally applied magnetic field
to demonstrate that a complete two- or three-dimensional structured rendering
of a sample can be obtained without the motion of the sample relative to the
sphere. Sequential positioning of the integrated sample-sphere system in an
external magnetic field at various angular orientations provides all the
required imaging slices for successful computerized tomographic image
reconstruction. The elimination of the requirement to scan the sample relative
to the ferromagnetic tip in this imaging protocol is a potentially valuable
simplification compared to previous scanning probe magnetic resonance imaging
proposals.


title: Simulations in statistical physics and biology: some applications

abstract:
  One of the most active areas of physics in the last decades has been that of
critical phenomena, and Monte Carlo simulations have played an important role
as a guide for the validation and prediction of system properties close to the
critical points. The kind of phase transitions occurring for the Betts lattice
(lattice constructed removing 1/7 of the sites from the triangular lattice)
have been studied before with the Potts model for the values q=3, ferromagnetic
and antiferromagnetic regime. Here, we add up to this research line the
ferromagnetic case for q=4 and 5. In the first case, the critical exponents are
estimated for the second order transition, whereas for the latter case the
histogram method is applied for the occurring first order transition.
Additionally, Domany's Monte Carlo based clustering technique mainly used to
group genes similar in their expression levels is reviewed. Finally, a control
theory tool --an adaptive observer-- is applied to estimate the exponent
parameter involved in the well-known Gompertz curve. By treating all these
subjects our aim is to stress the importance of cooperation between distinct
disciplines in addressing the complex problems arising in biology.
  Contents: Chapter 1 - Monte Carlo simulations in stat. physics; Chapter 2: MC
simulations in biology; Chapter 3: Gompertz equation


title:
Moody's Correlated Binomial Default Distributions for Inhomogeneous
  Portfolios

abstract:
  This paper generalizes Moody's correlated binomial default distribution for
homogeneous (exchangeable) credit portfolio, which is introduced by Witt, to
the case of inhomogeneous portfolios. As inhomogeneous portfolios, we consider
two cases. In the first case, we treat a portfolio whose assets have uniform
default correlation and non-uniform default probabilities. We obtain the
default probability distribution and study the effect of the inhomogeneity on
it. The second case corresponds to a portfolio with inhomogeneous default
correlation. Assets are categorized in several different sectors and the
inter-sector and intra-sector correlations are not the same. We construct the
joint default probabilities and obtain the default probability distribution. We
show that as the number of assets in each sector decreases, inter-sector
correlation becomes more important than intra-sector correlation. We study the
maximum values of the inter-sector default correlation. Our generalization
method can be applied to any correlated binomial default distribution model
which has explicit relations to the conditional default probabilities or
conditional default correlations, e.g. Credit Risk${}^{+}$, implied default
distributions. We also compare some popular CDO pricing models from the
viewpoint of the range of the implied tranche correlation.


title:
Calibration of optical tweezers with positional detection in the
  back-focal-plane

abstract:
  We explain and demonstrate a new method of force- and position-calibration
for optical tweezers with back-focal-plane photo detection. The method combines
power spectral measurements of thermal motion and the response to a sinusoidal
motion of a translation stage. It consequently does not use the drag
coefficient of the trapped ob ject as an input. Thus, neither the viscosity,
nor the size of the trapped ob ject, nor its distance to nearby surfaces need
to be known. The method requires only a low level of instrumentation and can be
applied in situ in all spatial dimensions. It is both accurate and precise:
true values are returned, with small error-bars. We tested this experimentally,
near and far from surfaces. Both position- and force-calibration were accurate
to within 3%. To calibrate, we moved the sample with a piezo-electric
translation stage, but the laser beam could be moved instead, e.g. by
acousto-optic deflectors. Near surfaces, this precision requires an improved
formula for the hydrodynamical interaction between an infinite plane and a
micro-sphere in non-constant motion parallel to it. We give such a formula.


title: Dipole blockade through Rydberg Forster resonance energy transfer

abstract:
  High resolution laser excitation of np Rydberg states of cesium atoms shows a
dipole blockade at F\"{o}rster resonances corresponding to the resonant
dipole-dipole energy transfer of the np + np → ns + (n + 1)s reaction.
The dipole-dipole interaction can be tuned on and off by the Stark effect, and
such a process observed for relatively low n (25 − 41) is promising for
quantum gate devices. Both Penning ionization and saturation in the laser
excitation can limit the range of observation of the dipole blockade


title: Bruno Pontecorvo: mister neutrino

abstract:
  Bruno Pontecorvo was a great physicist who had enormous impact on the
development of neutrino physics. His contribution to neutrino physics is
briefly reviewed.Some recollections about his personality are also given.


title: Evaluation of Tranche in Securitization and Long-range Ising Model

abstract:
  This econophysics work studies the long-range Ising model of a finite system
with $N$ spins and the exchange interaction $\frac{J}{N}$ and the external
field $H$ as a modely for homogeneous credit portfolio of assets with default
probability $P_{d}$ and default correlation $\rho_{d}$. Based on the discussion
on the $(J,H)$ phase diagram, we develop a perturbative calculation method for
the model and obtain explicit expressions for $P_{d},\rho_{d}$ and the
normalization factor $Z$ in terms of the model parameters $N$ and $J,H$. The
effect of the default correlation $\rho_{d}$ on the probabilities
$P(N_{d},\rho_{d})$ for $N_{d}$ defaults and on the cumulative distribution
function $D(i,\rho_{d})$ are discussed. The latter means the average loss rate
of the``tranche'' (layered structure) of the securities (e.g. CDO), which are
synthesized from a pool of many assets. We show that the expected loss rate of
the subordinated tranche decreases with $\rho_{d}$ and that of the senior
tranche increases linearly, which are important in their pricing and ratings.


title:
Totally secure classical networks with multipoint telecloning
  (teleportation) of classical bits through loops with Johnson-like noise

abstract:
  First, we show a new inexpensive defense against intruders and the
man-in-the-middle attack in the Kirchhoff's-loop-Johnson-like-noise (KLJN)
cipher. Then instead of point-to-point communication, we propose a high
efficiency, secure network. The (in the idealistic case totally secure)
classical network is based on an improved version of the KLJN cipher. The
network consists of two parallel networks: i) a chain-like network of securely
communicating, electrically isolated Kirchhoff-loops with Johnson-like noise
and driven by a specific switching process of the resistances; ii) and a
regular non-secure data network with a Coordinator-server. If the classical
network is fast enough, the chain-like network of N communicators can generate
and share an N bit long secret key within a single clock period of the ciphers
and that implies a significant speed-up compared to the point-to-point key
exchanges used by quantum communication or RSA-like key exchange methods. This
is a teleportation-type multiple telecloning of the classical information bit
because the information transfer can take place without the actual presence of
the information bit at the intermediate points of the network. With similar
quantum schemes the telecloning of classical bits via quantum communicator
networks without telecloning the quantum states is also possible.


title: Microscopic Abrams-Strogatz model of language competition

abstract:
  The differential equations of Abrams and Strogatz for the competition between
two languages are compared with agent-based Monte Carlo simulations for fully
connected networks as well as for lattices in one, two and three dimensions,
with up to 10^9 agents.


title: Violations of Einstein's time dilation formula in particle decays

abstract:
  A rigorous quantum relativistic approach has been used to calculate the
relationship between the decay laws of an unstable particle seen from two
inertial frames moving with respect to each other. In agreement with
experiment, it is found that the usual Einstein's time dilation formula is
rather accurate in this case. However, small corrections to this formula were
also obtained. Although the observation of these corrections is beyond the
resolution of modern experiments, their presence indicates that special
relativistic time dilation is not rigorously applicable to particle decays.


title: The Spread of Opinions and Proportional Voting

abstract:
  Election results are determined by numerous social factors that affect the
formation of opinion of the voters, including the network of interactions
between them and the dynamics of opinion influence. In this work we study the
result of proportional elections using an opinion dynamics model similar to
simple opinion spreading over a complex network. Erdos-Renyi, Barabasi-Albert,
regular lattices and randomly augmented lattices are considered as models of
the underlying social networks. The model reproduces the power law behavior of
number of candidates with a given number of votes found in real elections with
the correct slope, a cutoff for larger number of votes and a plateau for small
number of votes. It is found that the small world property of the underlying
network is fundamental for the emergence of the power law regime.


title:
All-optical octave-broad ultrafast switching of Si woodpile photonic
  band gap crystals

abstract:
  We present ultrafast all-optical switching measurements of Si woodpile
photonic band gap crystals. The crystals are spatially homogeneously excited,
and probed by measuring reflectivity over an octave in frequency (including the
telecom range) as a function of time. After 300 fs, the complete stop band has
shifted to higher frequencies as a result of optically excited free carriers.
The switched state relaxes quickly with a time constant of 18 ps. We present a
quantitative analysis of switched spectra with theory for finite photonic
crystals. The induced changes in refractive index are well described by a Drude
model with a carrier relaxation time of 10 fs. We briefly discuss possible
applications of high-repetition rate switching of photonic crystal cavities.


title:
Aerosol Characteristics at a High Altitude Location in Central
  Himalayas: Optical Properties and Radiative Forcing

abstract:
  Collocated measurements of the mass concentrations of aerosol black carbon
(BC) and composite aerosols near the surface were carried out along with
spectral aerosol optical depths (AODs) from a high altitude station, Manora
Peak in Central Himalayas, during a comprehensive aerosol field campaign in
December 2004. Despite being a pristine location in the Shivalik Ranges of
Central Himalayas, and having a monthly mean AOD (at 500 nm) of 0.059 $\pm$
0.033 (typical to this site), total suspended particulate (TSP) concentration
was in the range 15 - 40 micro g m^(-3) (mean value 27.1 $\pm$ 8.3 micro g
m^(-3)). Interestingly, aerosol BC had a mean concentration of 1.36 $\pm$ 0.99
micro g m^(-3), contributed to ~5.0 $\pm$ 1.3 % to the composite aerosol mass.
This large abundance of BC is found to have linkages to the human activities in
the adjoining valley and to the boundary layer dynamics. Consequently, the
inferred single scattering albedo lies in the range of 0.87 to 0.94 (mean value
0.90 $\pm$ 0.03), indicating significant aerosol absorption. The estimated
aerosol radiative forcing was as low as 4.2 W m^(-2) at the surface, +0.7 W
m^(-2) at the top of the atmosphere, implying an atmospheric forcing of +4.9 W
m^(-2). Though absolute value of the atmospheric forcing is quite small, which
arises primarily from the very low AOD (or the column abundance of aerosols),
the forcing efficiency (forcing per unit optical depth) was $\sim$88 W m^(-2),
which is attributed to the high BC mass fraction.


title: Van Kampen's expansion approach in an opinion formation model

abstract:
  We analyze a simple opinion formation model consisting of two parties, A and
B, and a group I, of undecided agents. We assume that the supporters of parties
A and B do not interact among them, but only interact through the group I, and
that there is a nonzero probability of a spontaneous change of opinion (A->I,
B->I). From the master equation, and via van Kampen's Omega-expansion approach,
we have obtained the "macroscopic" evolution equation, as well as the
Fokker-Planck equation governing the fluctuations around the deterministic
behavior. Within the same approach, we have also obtained information about the
typical relaxation behavior of small perturbations.


title: Stabilisation of BGK modes by relativistic effects

abstract:
  We investigate the acceleration of electrons via their interaction with
electrostatic waves, driven by the relativistic Buneman instability, in a
system dominated by counter-propagating proton beams. We observe the growth of
these waves and their subsequent saturation via electron trapping for a range
of proton beam velocities, from 0.15c to 0.9c. We can report a reduced
stability of the electrostatic wave (ESW) with increasing non-relativistic beam
velocities and an improved wave stability for increasing relativistic beam
velocities, both in accordance with previous findings. At the highest beam
speeds, we find the system to be stable again for a period of ~160 plasma
periods. Furthermore we observe a, to our knowledge, previously unreported
secondary electron acceleration mechanism at low beam speeds. We believe that
it is the result of parametric couplings to produce high phase velocity ESW's
which then trap electrons, accelerating them to higher energies. This allows
electrons in our simulation study to achieve the injection energy required for
Fermi acceleration, for beam speeds as low as 0.15c in unmagnetised plasma.


title: Stepwise bending of DNA by a single TATA-box Binding Protein

abstract:
  The TATA-box Binding Protein (TBP) is required by all three eukaryotic RNA
polymerases for the initiation of transcription from most promoters. TBP
recognizes, binds to, and bends promoter sequences called ``TATA-boxes'' in the
DNA. We present results from the study of individual Saccharomyces cerevisia
TBPs interacting with single DNA molecules containing a TATA-box. Using video
microscopy, we observed the Brownian motion of beads tethered by short
surface-bound DNA. When TBP binds to and bends the DNA, the conformation of the
DNA changes and the amplitude of Brownian motion of the tethered bead is
reduced compared to that of unbent DNA. We detected individual binding and
dissociation events and derived kinetic parameters for the process.
Dissociation was induced by increasing the salt concentration or by directly
pulling on the tethered bead using optical tweezers. In addition to the
well-defined free and bound classes of Brownian motion, we observed another two
classes of motion. These extra classes were identified with intermediate states
on a three-step, linear binding pathway. Biological implications of the
intermediate states are discussed.


title: Geometric optics of whispering gallery modes

abstract:
  Quasiclassical approach and geometric optics allow to describe rather
accurately whispering gallery modes in convex axisymmetric bodies. Using this
approach we obtain practical formulas for the calculation of eigenfrequencies
and radiative Q-factors in dielectrical spheroid and compare them with the
known solutions for the particular cases and with numerical calculations. We
show how geometrical interpretation allows expansion of the method on arbitrary
shaped axisymmetric bodies.


title:
FDTD analysis of the tunneling and growing exponential in a pair of
  epsilon-negative and mu-negative slabs

abstract:
  Pairing together material slabs with opposite signs for the real parts of
their constitutive parameters has been shown to lead to interesting and
unconventional properties that are not otherwise observable for single slabs.
One such case was demonstrated analytically for the conjugate (i.e.,
complementary) pairing of infinite planar slabs of epsilon-negative (ENG) and
mu-negative (MNG) media [A. Alu, and N. Engheta, IEEE Trans. Antennas Prop.,
51, 2558 (2003)]. There it was shown that when these two slabs are juxtaposed
and excited by an incident plane wave, resonance, complete tunneling, total
transparency and reconstruction of evanescent waves may occur in the
steady-state regime under a monochromatic excitation, even though each of the
two slabs by itself is essentially opaque to the incoming radiation. This may
lead to virtual imagers with sub-wavelength resolution and other anomalous
phenomena overcoming the physical limit of diffraction. Here we explore how a
transient sinusoidal signal that starts at t = 0 interacts with such an ENG-MNG
pair of finite size using an FDTD technique. Multiple reflections and
transmissions at each interface are shown to build up to the eventual steady
state response of the pair, and during this process one can observe how the
growing exponential phenomenon may actually occur inside this bilayer.


title:
Optical Nanotransmission Lines: Synthesis of Planar Left-Handed
  Metamaterials in the Infrared and Visible Regimes

abstract:
  Following our recent theoretical development of the concept of
nano-inductors, nano-capacitors and nano-resistors at optical frequencies and
the possibility of synthesizing more complex nano-scale circuits, here we
theoretically investigate in detail the problem of optical
nano-transmission-lines (NTL) that can be envisioned by properly joining
together arrays of these basic nano-scale circuit elements. We show how, in the
limit in which these basic circuit elements are closely packed together, the
NTLs can be regarded as stacks of plasmonic and non-plasmonic planar slabs,
which may be designed to effectively exhibit the properties of planar
metamaterials with forward (right-handed) or backward (left-handed) operation.
With the proper design, negative refraction and left-handed propagation are
shown to be possible in these planar plasmonic guided-wave structures,
providing possibilities for sub-wavelength focusing and imaging in planar
optics, and laterally-confined waveguiding at IR and visible frequencies. The
effective material parameters for such NTLs are derived, and the connection and
analogy between these optical NTLs and the double-negative and double-positive
metamaterials are also explored. Physical insights and justification for the
results are also presented.


title: La relativeca tempo - I / The relativistic time - I

abstract:
  The relativistic time is different from the Newtonian one. We revisit some of
these differences in Doppler effect, twin paradox, rotation, rigid rod, and
constant proper acceleration. ------- La relativeca tempo estas malsama ol la
Newtona. Ni revidos iujn el tiuj malsamoj en Dopplera efiko, gxemel-paradokso,
rotacio, rigida stango, kaj konstanta propra akcelo.


title: Quantum properties of a cyclic structure based on tripolar fields

abstract:
  The properties of cyclic structures (toroidal oscillators) based on classical
tripolar (colour) fields are discussed, in particular, of a cyclic structure
formed of three colour-singlets spinning around a ring-closed axis. It is shown
that the helicity and handedness of this structure can be related to the
quantum properties of the electron. The symmetry of this structure corresponds
to the complete cycle of ${2/3}\pi$-rotations of its constituents, which leads
to the exact overlapping of the paths of its three complementary coloured
constituents, making the system dynamically colourless. The gyromagnetic ratio
of this system is estimated to be g$\approx 2$, which agrees with the Land\'e
g-factor for the electron.


title:
Auxiliary-field quantum Monte Carlo calculations of molecular systems
  with a Gaussian basis

abstract:
  We extend the recently introduced phaseless auxiliary-field quantum Monte
Carlo (QMC) approach to any single-particle basis, and apply it to molecular
systems with Gaussian basis sets. QMC methods in general scale favorably with
system size, as a low power. A QMC approach with auxiliary fields in principle
allows an exact solution of the Schrodinger equation in the chosen basis.
However, the well-known sign/phase problem causes the statistical noise to
increase exponentially. The phaseless method controls this problem by
constraining the paths in the auxiliary-field path integrals with an
approximate phase condition that depends on a trial wave function. In the
present calculations, the trial wave function is a single Slater determinant
from a Hartree-Fock calculation. The calculated all-electron total energies
show typical systematic errors of no more than a few milli-Hartrees compared to
exact results. At equilibrium geometries in the molecules we studied, this
accuracy is roughly comparable to that of coupled-cluster with single and
double excitations and with non-iterative triples, CCSD(T). For stretched bonds
in H$_2$O, our method exhibits better overall accuracy and a more uniform
behavior than CCSD(T).


title: Two-electron photoionization of endohedral atoms

abstract:
  Using $He@C_{60}$ as an example, we demonstrate that static potential of the
fullerene core essentially alters the cross section of the two-electron
ionization differential in one-electron energy $d\sigma ^{++}(\omega
)/d\epsilon $. We found that at high photon energy prominent oscillations
appear in it due to reflection of the second, slow electron wave on the $%
C_{60}$ shell, which "dies out" at relatively high $\epsilon $ values, of about
2$\div $3 two-electron ionization potentials. The results were presented for
ratios $R_{C_{60}}(\omega ,\epsilon)\equiv d\sigma ^{++}(\omega
,\epsilon)/d\sigma ^{a++}(\omega,\epsilon)$, where $d\sigma
^{a++}(\omega,\epsilon)/d\epsilon$ is the two-electron differential
photoionization cross section. We have calculated the ratio $R_{i,ful}=
\sigma_{i} ^{++}(\omega)/\sigma_{i}^{a++}(\omega)$, that accounts for
reflection of both photoelectrons by the $C_{60}$ shell. We have calculated
also the value of two-electron photoionization cross section $\sigma
^{++}(\omega)$ and found that this value is close to that of an isolated $He$
atom.


title: Drops on an inclined heterogeneous substrate: onset of sliding motion

abstract:
  Pinning and depinning of drops on an inclined heterogeneous substrate is
studied as a function of the inclination and heterogeneity amplitude. Two types
of heterogeneity are considered: a hydrophobic defect that blocks the droplet
in front, and a hydrophilic one that holds it at the back. Two different types
of depinning leading to sliding motion are identified, and the resulting
stick-slip motion is studied numerically.


title: Flow channelling in a single fracture induced by shear displacement

abstract:
  The effect on the transport properties of fractures of a relative shear
displacement $\vec u$ of rough walls with complementary self-affine surfaces
has been studied experimentally and numerically. The shear displacement $\vec
u$ induces an anisotropy of the aperture field with a correlation length
scaling as $u$ and significantly larger in the direction perpendicular to $\vec
u$. This reflects the appearance of long range channels perpendicular to $\vec
u$ resulting in a higher effective permeability for flow in the direction
perpendicular to the shear. Miscible displacements fronts in such fractures are
observed experimentally to display a self affine geometry of characteristic
exponent directly related to that of the rough wall surfaces. A simple model
based on the channelization of the aperture field allows to reproduces the
front geometry when the mean flow is parallel to the channels created by the
shear displacement.


title: Comment on "Nuclear Emissions During Self-Nucleated Acoustic Cavitation"

abstract:
  In a recent Letter to PRL, Taleyarkhan and coauthors claim to observe DD
fusion produced by acoustic cavitation. Among other evidence, they provide a
proton recoil spectrum that they interpret as arising from 2.45 MeV DD fusion
neutrons. My analysis concludes the spectrum is inconsistent with 2.45 MeV
neutrons, cosmic background, or a PuBe source, but it is consistent with a
Cf-252 source.


title: The Power-law Tail Exponent of Income Distributions

abstract:
  In this paper we tackle the problem of estimating the power-law tail exponent
of income distributions by using the Hill's estimator. A subsample
semi-parametric bootstrap procedure minimising the mean squared error is used
to choose the power-law cutoff value optimally. This technique is applied to
personal income data for Australia and Italy.


title: Using resource graphs to represent conceptual change

abstract:
  We introduce resource graphs, a representation of linked ideas used when
reasoning about specific contexts in physics. Our model is consistent with
previous descriptions of resources and coordination classes. It can represent
mesoscopic scales that are neither knowledge-in-pieces or large-scale concepts.
We use resource graphs to describe several forms of conceptual change:
incremental, cascade, wholesale, and dual construction. For each, we give
evidence from the physics education research literature to show examples of
each form of conceptual change. Where possible, we compare our representation
to models used by other researchers. Building on our representation, we
introduce a new form of conceptual change, differentiation, and suggest several
experimental studies that would help understand the differences between
reform-based curricula.


title: Unified Theory of Allometric Scaling

abstract:
  A general simple theory for the interspecific allometric scaling is developed
in the $d+1$-dimensional space ($d$ biological lengths and a physiological
time) of metabolic states of organisms. It is assumed that natural selection
shaped the metabolic states in such a way that the mass and energy
$d+1$-densities are size-invariant quantities (independent of body mass). The
different metabolic states (basal and maximum) are described by considering
that the biological lengths and the physiological time are related by different
transport processes of energy and mass. In the basal metabolism, transportation
occurs by ballistic and diffusion processes. In $d=3$, the 3/4 law occurs if
the ballistic movement is the dominant process, while the 2/3 law appears when
both transport processes are equivalent. Accelerated movement during the
biological time is related to the maximum aerobic sustained metabolism, which
is characterized by the scaling exponent $2d/(2d+1)$ (6/7 in $d=3$). The
results are in good agreement with empirical data and a verifiable empirical
prediction about the aorta blood velocity in maximum metabolic rate conditions
is made.


title: Impact of memory on human dynamics

abstract:
  Our experience of web access slowing down is a consequence of the aggregated
web access pattern of web users. This is just one example among several human
oriented services which are strongly affected by human activity patterns.
Recent empirical evidence is indicating that human activity patterns are
characterized by power law distributions of inter-event times, where large
fluctuations rather than regularity is the common case. I show that this
temporal heterogeneity can be explained by two mechanisms: (i) humans have some
perception of their past activity rate and (ii) based on that they react by
accelerating or reducing their activity rate. Using these two mechanisms I
explain the inter-event time statistics of Darwin's and Einstein's
correspondence and the email activity within an university environment.
Moreover, they are typical examples of the the accelerating and reducing class,
respectively. These results are relevant to the system design of human oriented
services.


title:
Spectral Analysis of Dow Jones Index and Comparison with Model Predicted
  Cycles During 1900-2005

abstract:
  The day-to day fluctuations of Dow Jones Index exhibit fractal fluctuations,
namely, a zigzag pattern of successive increases followed by decreases on all
space-time scales. Self-similar fractal fluctuations are generic to dynamical
systems in nature and imply long-range space-time correlations. The apparently
unpredictable (chaotic) fluctuations of dynamical systems exhibit underlying
order with the power spectra exhibiting inverse power law form, now identified
as self-organized criticality. The physics of self-organized criticality is not
yet identified. A general systems theory developed by the author shows that
self-similar fractal fluctuations are signatures of quantum-like chaos in
dynamical systems of all size scales ranging from the subatomic dynamics of
quantum systems to macro-scale fluid flows. The model predicts the universal
inverse power-law form of the statistical normal distribution for the power
spectra of fractal space-time fluctuations of dynamical systems. In this paper
it is shown that the power spectrum of 100 years of normalized month to month
fluctuations of Dow Jones index exhibits the universal inverse power law form
of the statistical normal distribution consistent with model prediction. It is
shown that prediction of times of occurrence of maxima and minima during the
two years subsequent to the data period used for the study is possible using
the dominant peak periodicities obtained from the continuous periodogram
spectral analysis of historic data.


title: Dynamical Friction in Stellar Systems: an introduction

abstract:
  An introductory exposition of Chandrasekhar's gravitational dynamical
friction, appropriate for an undergraduate class in mec hanics, is presented.
This friction results when a massive particle moving through a ``sea'' of much
lighter star particles experiences a retarding force du to an exchange of
energy and momentum. General features of dynamical friction are presented, both
in an elementary and in a more elaborate way using hyperbolic two-body
interactions. The orbital decay of a massive particle in an homogeneous
gravitational system is solved analytically, that leads to an underdamped
harmonic oscillator type of motion. A numerical integration of the equation of
motion in a more realistic c ase is done. These results are compared to those
of an N-body computer simulation. Several problems and projects are suggested
to students for further st udy.


title: Surface polaritons in two-dimensional left-handed photonic crystals

abstract:
  Using an extended plane-wave-based transfer-matrix method, the photonic band
structures and the corresponding transmission spectrum of a two-dimensional
left-handed photonic crystal are calculated. Comparisons between the periodic
structure with a single left-handed cylindric rod are made, and many
interesting similarities are found. It is shown that, due to the localized
surface polaritons presented by an isolated left-handed rod, there exist many
exciting physical phenomena in high-dimensional left-handed photonic crystals.
As direct results of coupling of the localized surface polaritons of
neighboring left-handed rod, a lot of almost dispersionless bands,
anti-crossing behavior, and a zero $\bar{n}$ gap are exhibited in the
left-handed periodic structure. Moreover, in a certain frequency region, except
distorted by a lot of anti-crossing behavior, there exists a continual
dispersion relation, which can be explained by the long-wavelength
approximation. It is also pointed out that high-dimensional left-handed
photonic crystals can be used to design narrow-band filter.


title: A simplex model for layered niche networks

abstract:
  The standing crop of correlations in metazoan communities may be assessed by
an inventory of niche structures focused inward and outward from the physical
boundaries of skin (self), gene-pool (family), and meme-pool (culture). We
consider tracking the progression from three and four correlation layers in
many animal communities, to five of six layers for the shared adaptation of
most humans, with an attention-slice model that maps the niche-layer focus of
individuals onto the 6-variable space of a 5-simplex. The measure puts
questions about the effect, on culture and species, of policy and natural
events into a common context, and may help explore the impact of
electronically-mediated codes on community health.


title:
Polarization operator approach to electron-positron pair production in
  combined laser and Coulomb fields

abstract:
  The optical theorem is applied to the process of electron-positron pair
creation in the superposition of a nuclear Coulomb and a strong laser field. We
derive new representations for the total production rate as two-fold integrals,
both for circular laser polarization and for the general case of elliptic
polarization, which has not been treated before. Our approach allows us to
obtain by analytical means the asymptotic behaviour of the pair creation rate
for various limits of interest. In particular, we consider pair production by
two-photon absorption and show that, close to the energetic threshold of this
process, the rate obeys a power law in the laser frequency with different
exponents for linear and circular laser polarization. With the help of the
upcoming x-ray laser sources our results could be tested experimentally.


title:
An adaptive grid refinement strategy for the simulation of negative
  streamers

abstract:
  The evolution of negative streamers during electric breakdown of a
non-attaching gas can be described by a two-fluid model for electrons and
positive ions. It consists of continuity equations for the charged particles
including drift, diffusion and reaction in the local electric field, coupled to
the Poisson equation for the electric potential. The model generates field
enhancement and steep propagating ionization fronts at the tip of growing
ionized filaments. An adaptive grid refinement method for the simulation of
these structures is presented. It uses finite volume spatial discretizations
and explicit time stepping, which allows the decoupling of the grids for the
continuity equations from those for the Poisson equation. Standard refinement
methods in which the refinement criterion is based on local error monitors fail
due to the pulled character of the streamer front that propagates into a
linearly unstable state. We present a refinement method which deals with all
these features. Tests on one-dimensional streamer fronts as well as on
three-dimensional streamers with cylindrical symmetry (hence effectively 2D for
numerical purposes) are carried out successfully. Results on fine grids are
presented, they show that such an adaptive grid method is needed to capture the
streamer characteristics well. This refinement strategy enables us to
adequately compute negative streamers in pure gases in the parameter regime
where a physical instability appears: branching streamers.


title:
Nonextensive statistical features of the Polish stock market
  fluctuations

abstract:
  The statistics of return distributions on various time scales constitutes one
of the most informative characteristics of the financial dynamics. Here we
present a systematic study of such characteristics for the Polish stock market
index WIG20 over the period 04.01.1999 - 31.10.2005 for the time lags ranging
from one minute up to one hour. This market is commonly classified as emerging.
Still on the shortest time scales studied we find that the tails of the return
distributions are consistent with the inverse cubic power-law, as identified
previously for majority of the mature markets. Within the time scales studied a
quick and considerable departure from this law towards a Gaussian can however
be traced. Interestingly, all the forms of the distributions observed can be
comprised by the single $q$-Gaussians which provide a satisfactory and at the
same time compact representation of the distribution of return fluctuations
over all magnitudes of their variation. The corresponding nonextensivity
parameter $q$ is found to systematically decrease when increasing the time
scales.

categories: physics.data-an astro-ph cond-mat.stat-mech physics.comp-ph q-fin.ST


title:
Geometrical Optics of Beams with Vortices: Berry Phase and Orbital
  Angular Momentum Hall Effect

abstract:
  We consider propagation of a paraxial beam carrying the spin angular momentum
(polarization) and intrinsic orbital angular momentum (IOAM) in a smoothly
inhomogeneous isotropic medium. It is shown that the presence of IOAM can
dramatically enhance and rearrange the topological phenomena that previously
were considered solely in connection to the polarization of transverse waves.
In particular, the appearance of a new-type Berry phase that describes the
parallel transport of the beam structure along a curved ray is predicted. We
derive the ray equations demonstrating the splitting of beams with different
values of IOAM. This is the orbital angular momentum Hall effect, which
resembles Magnus effect for optical vortices. Unlike the recently discovered
spin Hall effect of photons, it can be much larger in magnitude and is inherent
to waves of any nature. Experimental means to detect the phenomena is
discussed.


title:
Power Spectrum Analysis for Optical Tweezers, II: Laser Wavelength
  Dependence of Parasitic Filtering, and how to Achieve High Band-Width

abstract:
  In a typical optical tweezers detection system, the position of a trapped
object is determined from laser light impinging on a quadrant photodiode. When
the laser is infrared and the photodiode is of silicon, they can act together
as an unintended low-pass filter. This parasitic effect is due to the high
transparency of silicon to near-infrared light. A simple model that accounts
for this phenomenon (Berg-Sorensen et al., J. Appl. Phys., 93, 3167-3176
(2003)) is here solved for frequencies up to 100 kHz, and for laser wavelengths
between 750 and 1064 nm. The solution is applied to experimental data in the
same range, and is demonstrated to give this detection system of optical
tweezers a bandwidth, accuracy, and precision that is limited only by the data
acquisition board's band-width and bandpass ripples, here 96.7 kHz, resp. 0.005
dB.


title: Hypothesis of a Mundane Solution to the Pioneer Anomaly

abstract:
  Incorporating the relativistic all-angle Doppler shift equation in the
interpretation of astronomical Doppler shift may help explain the Pioneer
anomaly and other phenomena.


title: Possible Solution to the Poincare Conjecture

abstract:
  The Poincare conjecture is analyzed in the context of Calabi-Yau $n$-folds. A
simple treatment is given by embedding the three-manifolds into these CY
manifolds, and then taking the orbifold limit. The higher-dimensional proofs
are also available in this context.


title:
Living in an Irrational Society: Wealth Distribution with Correlations
  between Risk and Expected Profits

abstract:
  Different models to study the wealth distribution in an artificial society
have considered a transactional dynamics as the driving force. Those models
include a risk aversion factor, but also a finite probability of favoring the
poorer agent in a transaction. Here we study the case where the partners in the
transaction have a previous knowledge of the winning probability and adjust
their risk aversion taking this information into consideration. The results
indicate that a relatively equalitarian society is obtained when the agents
risk in direct proportion to their winning probabilities. However, it is the
opposite case that delivers wealth distribution curves and Gini indices closer
to empirical data. This indicates that, at least for this very simple model,
either agents have no knowledge of their winning probabilities, either they
exhibit an ``irrational'' behavior risking more than reasonable.


title:
Variational calculation of the limit cycle and its frequency in a
  two-neuron model with delay

abstract:
  We consider a model system of two coupled Hopfield neurons, which is
described by delay differential equations taking into account the finite signal
propagation and processing times. When the delay exceeds a critical value, a
limit cycle emerges via a supercritical Hopf bifurcation. First, we calculate
its frequency and trajectory perturbatively by applying the
Poincar\'e-Lindstedt method. Then, the perturbation series are resummed by
means of the Shohat expansion in good agreement with numerical values. However,
with increasing delay, the accuracy of the results from the Shohat expansion
worsens. We thus apply variational perturbation theory (VPT) to the
perturbation expansions to obtain more accurate results, which moreover hold
even in the limit of large delays.


title: Davies ENDOR revisited: Enhanced sensitivity and nuclear spin relaxation

abstract:
  Over the past 50 years, electron-nuclear double resonance (ENDOR) has become
a fairly ubiquitous spectroscopic technique, allowing the study of spin
transitions for nuclei which are coupled to electron spins. However, the low
spin number sensitivity of the technique continues to pose serious limitations.
Here we demonstrate that signal intensity in a pulsed Davies ENDOR experiment
depends strongly on the nuclear relaxation time T1n, and can be severely
reduced for long T1n. We suggest a development of the original Davies ENDOR
sequence that overcomes this limitation, thus offering dramatically enhanced
signal intensity and spectral resolution. Finally, we observe that the
sensitivity of the original Davies method to T1n can be exploited to measure
nuclear relaxation, as we demonstrate for phosphorous donors in silicon and for
the endohedral fullerene N@C60 in CS2.


title:
Reflectionless evanescent-wave amplification by two dielectric planar
  waveguides

abstract:
  Utilizing the underlying physics of evanescent wave amplification by a
negative-refractive-index slab, it is shown that evanescent waves with specific
spatial frequencies can also be amplified without any reflection simply by two
dielectric planar waveguides. The simple configuration allows one to take
advantage of the high resolution limit of a high-refractive-index material
without contact with the object.


title:
Energy flow lines as light paths: a didactical analysis
  (Energiestromlinien als Lichtwege: Eine didaktische Analyse)

abstract:
  Analyses of interviews with secondary school students about their conceptions
of light at the University of Potsdam indicate that numerous students have a
deterministic view of light. With regard to these results the model of energy
flow lines, which has been discussed recently in the didactical literature, is
of special interest. Following this model, light is presumed to move along
energy flow lines as trajectories. In an analysis of the model of energy flow
lines four didactical dimensions (didactical content, internal structure,
present-day relevance and future significance) are investigated. It can be
shown that a discussion of this model in physics at school can increase the
meta-conceptional knowledge of the students about the models of light. On the
other hand, this can promote deterministic conceptions and the Bohm
interpretation of quantum mechanics. But the question remains: Should the
nature of light really be described as deterministic?


title:
Power-law Strength-Degree Correlation From a Resource-Allocation
  Dynamics on Weighted Networks

abstract:
  Many weighted scale-free networks are known to have a power-law correlation
between strength and degree of nodes, which, however, has not been well
explicated. We investigate the dynamic behaviors of resource/traffic flow on
scale-free networks. The dynamical system will evolve to a kinetic equilibrium
state, where the strength, defined by the amount of resource or traffic load,
is correlated with the degree in a power-law form with tunable exponent. The
analytical results agree with simulations well.


title:
A unified approach to describe optical pulse generation by propagation
  of periodically phase-modulated CW laser light

abstract:
  The analysis of optical pulse generation by phase modulation of narrowband
continuous-wave light, and subsequent propagation through a
group-delay-dispersion circuit, is usually performed in terms of the so-called
bunching parameter. This heuristic approach does not provide theoretical
support for the electrooptic flat-top-pulse generation reported recently. Here,
we perform a waveform synthesis in terms of the Fresnel images of the
periodically phase-modulated input light. In particular, we demonstrate
flat-top-pulse generation with a duty ratio of 50% at a quarter of the Talbot
condition for the sinusoidal phase modulation. Finally, we propose a binary
modulation format to generate a well-defined square-wave-type optical bit
pattern.


title: El Nino and the Delayed Action Oscillator

abstract:
  We study the dynamics of the El Nino phenomenon using the mathematical model
of delayed-action oscillator (DAO). Topics such as the influence of the annual
cycle, global warming, stochastic influences due to weather conditions and even
off-equatorial heat-sinks can all be discussed using only modest analytical and
numerical resources. Thus the DAO allows for a pedagogical introduction to the
science of El Nino and La Nina while at the same time avoiding the need for
large-scale computing resources normally associated with much more
sophisticated coupled atmosphere-ocean general circulation models. It is an
approach which is ideally suited for student projects both at high school and
undergraduate level.