title: Prospects for Money Transfer Models

abstract:
  Recently, in order to explore the mechanism behind wealth or income
distribution, several models have been proposed by applying principles of
statistical mechanics. These models share some characteristics, such as
consisting of a group of individual agents, a pile of money and a specific
trading rule. Whatever the trading rule is, the most noteworthy fact is that
money is always transferred from one agent to another in the transferring
process. So we call them money transfer models. Besides explaining income and
wealth distributions, money transfer models can also be applied to other
disciplines. In this paper we summarize these areas as statistical
distribution, economic mobility, transfer rate and money creation. First, money
distribution (or income distribution) can be exhibited by recording the money
stock (flow). Second, the economic mobility can be shown by tracing the change
in wealth or income over time for each agent. Third, the transfer rate of money
and its determinants can be analyzed by tracing the transferring process of
each one unit of money. Finally, money creation process can also be
investigated by permitting agents go into debts. Some future extensions to
these models are anticipated to be structural improvement and generalized
mathematical analysis.


title: Dynamic Process of Money Transfer Models

abstract:
  We have studied numerically the statistical mechanics of the dynamic
phenomena, including money circulation and economic mobility, in some transfer
models. The models on which our investigations were performed are the basic
model proposed by A. Dragulescu and V. Yakovenko [1], the model with uniform
saving rate developed by A. Chakraborti and B.K. Chakrabarti [2], and its
extended model with diverse saving rate [3]. The velocity of circulation is
found to be inversely related with the average holding time of money. In order
to check the nature of money transferring process in these models, we
demonstrated the probability distributions of holding time. In the model with
uniform saving rate, the distribution obeys exponential law, which indicates
money transfer here is a kind of Poisson process. But when the saving rate is
set diversely, the holding time distribution follows a power law. The velocity
can also be deduced from a typical individual's optimal choice. In this way, an
approach for building the micro-foundation of velocity is provided. In order to
expose the dynamic mechanism behind the distribution in microscope, we examined
the mobility by collecting the time series of agents' rank and measured it by
employing an index raised by economists. In the model with uniform saving rate,
the higher saving rate, the slower agents moves in the economy. Meanwhile, all
of the agents have the same chance to be the rich. However, it is not the case
in the model with diverse saving rate, where the assumed economy falls into
stratification. The volatility distribution of the agents' ranks are also
demonstrated to distinguish the differences among these models.


title: Bipartite Producer-Consumer Networks and the Size Distribution of Firms

abstract:
  A bipartite producer-consumer network is constructed to describe the
industrial structure. The edges from consumer to producer represent the choices
of the consumer for the final products and the degree of producer can represent
its market share. So the size distribution of firms can be characterized by
producer's degree distribution. The probability for a producer receiving a new
consumption is determined by its competency described by initial attractiveness
and the self-reinforcing mechanism in the competition described by preferential
attachment. The cases with constant total consumption and with growing market
are studied. The following results are obtained: 1, Without market growth and a
uniform initial attractiveness $a$, the final distribution of firm sizes is
Gamma distribution for $a>1$ and is exponential for $a=1$. If $a<1$, the
distribution is power in small size and exponential in upper tail; 2, For a
growing market, the size distribution of firms obeys the power law. The
exponent is affected by the market growth and the initial attractiveness of the
firms.


title:
A way to synchronize models with seismic faults for earthquake
  forecasting: Insights from a simple stochastic model

abstract:
  Numerical models are starting to be used for determining the future behaviour
of seismic faults and fault networks. Their final goal would be to forecast
future large earthquakes. In order to use them for this task, it is necessary
to synchronize each model with the current status of the actual fault or fault
network it simulates (just as, for example, meteorologists synchronize their
models with the atmosphere by incorporating current atmospheric data in them).
However, lithospheric dynamics is largely unobservable: important parameters
cannot (or can rarely) be measured in Nature. Earthquakes, though, provide
indirect but measurable clues of the stress and strain status in the
lithosphere, which should be helpful for the synchronization of the models. The
rupture area is one of the measurable parameters of earthquakes. Here we
explore how it can be used to at least synchronize fault models between
themselves and forecast synthetic earthquakes. Our purpose here is to forecast
synthetic earthquakes in a simple but stochastic (random) fault model. By
imposing the rupture area of the synthetic earthquakes of this model on other
models, the latter become partially synchronized with the first one. We use
these partially synchronized models to successfully forecast most of the
largest earthquakes generated by the first model. This forecasting strategy
outperforms others that only take into account the earthquake series. Our
results suggest that probably a good way to synchronize more detailed models
with real faults is to force them to reproduce the sequence of previous
earthquake ruptures on the faults. This hypothesis could be tested in the
future with more detailed models and actual seismic data.


title: Year-ahead prediction of US landfalling hurricane numbers

abstract:
  We present a simple method for the year-ahead prediction of the number of
hurricanes making landfall in the US. The method is based on averages of
historical annual hurricane numbers, and we perform a backtesting study to find
the length of averaging window that would have given the best predictions in
the past.


title: Adiabatic theorem for non-hermitian time-dependent open systems

abstract:
  In the conventional quantum mechanics (i.e., hermitian QM) the adia- batic
theorem for systems subjected to time periodic fields holds only for bound
systems and not for open ones (where ionization and dissociation take place)
[D. W. Hone, R. Ketzmerik, and W. Kohn, Phys. Rev. A 56, 4045 (1997)]. Here
with the help of the (t,t') formalism combined with the complex scaling method
we derive an adiabatic theorem for open systems and provide an analytical
criteria for the validity of the adiabatic limit. The use of the complex
scaling transformation plays a key role in our derivation. As a numerical
example we apply the adiabatic theorem we derived to a 1D model Hamiltonian of
Xe atom which interacts with strong, monochromatic sine-square laser pulses. We
show that the gener- ation of odd-order harmonics and the absence of
hyper-Raman lines, even when the pulses are extremely short, can be explained
with the help of the adiabatic theorem we derived.


title: Point Defects Influence on the Raman Spectrum of the Naphthalene

abstract:
  The carried out polarization examinations of C10H8 spectrums of small
frequencies of a Raman effect of light has revealed the presence of additional
lines of small intensity. Calculation of histograms of spectrums of the lattice
oscillations is carried out by Dyne's method. It is shown, that the presence of
vacancies in structure of C10H8 leads to occurrence of additional lines around
90 cm-1. Occurrence of lines at frequencies less then 30 cm-1 is attributed to
the presence of orientation disorder of molecules. Apparently, structure C10H8
has both types of defects, both orientation disorder of molecules and
vacancies, which causes occurrence of additional lines in a spectrum of small
frequencies.


title:
Disordered cellular automaton traffic flow model: Phase separated state,
  density waves and self organized criticality

abstract:
  We suggest a disordered traffic flow model that captures many features of
traffic flow. It is an extension of the Nagel-Schreckenberg (NaSch) stochastic
cellular automata for single line vehicular traffic model. It incorporates
random acceleration and deceleration terms that may be greater than one unit.
Our model leads under its intrinsic dynamics, for high values of braking
probability $p$, to a constant flow at intermediate densities without
introducing any spatial inhomogeneities. For a system of fast drivers $p\to 0$,
the model exhibits a density wave behavior that was observed in car following
models with optimal velocity. The gap of the disordered model we present
exhibits, for high values of $p$ and random deceleration, at a critical
density, a power law distribution which is a hall mark of a self organized
criticality phenomena.


title:
Local Measurements in a Particle Laden Jet Generated by a Convergent
  Nozzle

abstract:
  The work show the characterization of a particle laden turbulent jet. For the
velocity and mass flux masurements, a PDA system has been used. Either the
continuous phase (air) or the dispersed phase (glass spheres) are measured;
also, the single phase flow is measure to comparison.


title: A New Look at the Sub-electron Controversy Of Milikan & Ehrenhaft

abstract:
  The measurements of the electronic charge e, by Ehrenhaft and Millikan in the
early nineteen hundreds generated a bitter controversy between the orthodox and
the atomic points of views. Guided by the Pauli-Fermi neutrino model for
beta-decay in this paper we speculate that the introduction of a small
hypothetical force is adequate to account for most of the contentious
differences between the observations of Millikan and Ehrenhaft.


title: A Format for Instantons and Their Characterizations

abstract:
  A characterization of instanton contributions to gauge field theory is given.
The dynamics of instantons with the gluon field is given in terms of
'classical' instanton contributions, i.e. on the same footing as tree
amplitudes in field theory. This paramaterization depends on the kinematics of
the local instanton operators and their coupling dependence. A primary
advantage of this 'classical' formulation is that the weak-strong duality and
its relations with the perturbative sector are possibly made more manifest.


title: Moments of inertia for solids of revolution and variational methods

abstract:
  We present some formulae for the moments of inertia of homogeneous solids of
revolution in terms of the functions that generate the solids. The development
of these expressions exploits the cylindrical symmetry of these objects, and
avoids the explicit use of multiple integration, providing an easy and
pedagogical approach. The explicit use of the functions that generate the solid
gives the possibility of writing the moment of inertia as a functional, which
in turn allows us to utilize the calculus of variations to obtain a new insight
into some properties of this fundamental quantity. In particular, minimization
of moments of inertia under certain restrictions is possible by using
variational methods.


title: Sorption heat engines: simple inanimate negative entropy generators

abstract:
  The name 'sorption heat engines' is proposed for simple negative entropy
generators that are driven by thermal cycling and work on alternating
adsorption and desorption. These generators are in general not explicitly
recognized as heat engines. Their mechanism is applicable to the fields of
engineering, physics, chemistry, geology, and biology, in particular the origin
of life. Four kinds of sorption heat engines are distinguished depending on the
occurrence of changes in the adsorbent or adsorbate during the thermal cycle.


title:
Beam test calibration of the balloon-borne imaging calorimeter for the
  CREAM experiment

abstract:
  CREAM (Cosmic Ray Energetics And Mass) is a multi-flight balloon mission
designed to collect direct data on the elemental composition and individual
energy spectra of cosmic rays. Two instrument suites have been built to be
flown alternately on a yearly base. The tungsten/Sci-Fi imaging calorimeter for
the second flight, scheduled for December 2005, was calibrated with electron
and proton beams at CERN. A calibration procedure based on the study of the
longitudinal shower profile is described and preliminary results of the beam
test are presented.


title:
Classical Effects of Laser Pulse Duration on Strong-field Double
  Ionization

abstract:
  We use classical electron ensembles and the aligned-electron approximation to
examine the effect of laser pulse duration on the dynamics of strong-field
double ionization. We cover the range of intensities $10^{14}-10^{16} W/cm^2$
for the laser wavelength 780 nm. The classical scenario suggests that the
highest rate of recollision occurs early in the pulse and promotes double
ionization production in few-cycle pulses. In addition, the purely classical
ensemble calculation predicts an exponentially decreasing recollision rate with
each subsequent half cycle. We confirm the exponential behavior by trajectory
back-analysis.


title:
Monte Carlo tomographic reconstruction in SPECT impact of bootstrapping
  and number of generated events

abstract:
  In Single Photon Emission Computed Tomography (SPECT), 3D images usually
reconstructed by performing a set of bidimensional (2D) analytical or iterative
reconstructions can also be reconstructed using an iterative reconstruction
algorithm involving a 3D projector. Accurate Monte Carlo (MC) simulations
modeling all the physical effects that affect the imaging process can be used
to estimate this projector. However, the accuracy of the projector is affected
by the stochastic nature of MC simulations. In this paper, we study the
accuracy of the reconstructed images with respect to the number of simulated
histories used to estimate the MC projector. Furthermore, we study the impact
of applying the bootstrapping technique when estimating the projector


title: Constraints of Perception and Cognition in Relativistic Physics

abstract:
  This article explores the constraints of perception and cognition in
relativistic physics. Describing reality as a cognitive representation of our
sensory inputs, the article shows how the limitations in perception translate
to the properties of space and time in physics. This framework of looking at
the visual reality as our brain's representation limited by the speed of light
unifies and explains a wide array of seemingly unrelated astrophysical and
cosmological phenomena. Understanding the constraints on our space and time due
to the limitations in perception and cognitive representation opens the
possibility of understanding astrophysics and cosmology from a whole new
viewpoint.


title:
Analytical investigation of oscillations in intersecting flows of
  pedestrian and vehicle traffic

abstract:
  In two intersecting many-particle streams, one can often find the emergence
of oscillatory patterns. Here, we investigate the interaction of pedestrians
with vehicles, when they try to cross a road. A numerical study of this coupled
pedestrian-vehicle delay problem has been presented in a previous paper. Here,
we focus on the analytical treatment of the problem, which requires to use a
simplified car-following model. Our analytical results for the phase transition
to oscillatory pedestrian and traffic flows and the average waiting times are
well supported by numerical evaluations and give a detailed picture of the
collective dynamics emerging when pedestrians try to cross a road. The
mathematical expressions allow one to identify the dependence on model
parameters such as the vehicle or pedestrian arrival rate, and the safety
factor of pedestrian gap acceptance. We also calculate a formula for the
vehicle time gap distribution, which corresponds to the departure time
distribution of a M/D/1 queue.


title: Network of social groups or Let's have a party

abstract:
  We present a simple model for growing up and depletion of parties due to the
permanent communication between the participants of the events. Because of the
rapid exchange of information, everybody is able to evaluate its own and and
all other parties by means of the list of its friends. Therefore the number of
participants at different parties can be changed incessantly. Depending on the
deepness of the social contacts, which will be characterized by a parameter
$\alpha $, a stable distribution of party members emerges. At a critical
$\alpha_c$ an abrupt depletion of almost all parties is observed and as the
consequence all the peoples are assembled at a single party. The model is based
on a hierarchical social network. The probability that a certain person is
contacted to another one depends on the social distance introduced within the
network and homophily parameter $\alpha $.


title:
Frequency shifts of photoassociative spectra of ultracold metastable
  Helium atoms : a new measurement of the s-wave scattering length

abstract:
  We observe light-induced frequency shifts in one-color photoassociative
spectra of magnetically trapped $^4$He$^*$ atoms in the metastable $2^3S_1$
state. A pair of ultracold spin-polarized $2^3S_1$ helium atoms is excited into
a molecular bound state in the purely long range $0_u^+$ potential connected to
the $2^3S_1 - 2^3P_0$ asymptote. The shift arises from the optical coupling of
the molecular excited bound state with the scattering states and the bound
states of two colliding $2^3S_1$ atoms. We measure the frequency-shifts for
several ro-vibrational levels in the $0^+_u$ potential and find a linear
dependence on the photoassociation laser intensity. Comparison with a
theoretical analysis provides a good indication for the s-wave scattering
length $a$ of the quintet ($^5\Sigma_g^+$) potential, $a=7.2\pm 0.6$ nm, which
is significantly lower than most previous results obtained by non-spectroscopic
methods.


title:
Probabilistic state preparation of a single molecular ion by projection
  measurement

abstract:
  We show how to prepare a single molecular ion in a specific internal quantum
state in a situation where the molecule is trapped and sympathetically cooled
by an atomic ion and where its internal degrees of freedom are initially in
thermal equilibrium with the surroundings. The scheme is based on conditional
creation of correlation between the internal state of the molecule and the
translational state of the collective motion of the two ions, followed by a
projection measurement of this collective mode by atomic ion shelving
techniques. State preparation in a large number of internal states is possible.


title:
On simulations of the classical harmonic oscillator equation by
  difference equations

abstract:
  We show that any second order linear ordinary diffrential equation with
constant coefficients (including the damped and undumped harmonic oscillator
equation) admits an exact discretization, i.e., there exists a difference
equation whose solutions exactly coincide with solutions of the corresponding
differential equation evaluated at a discrete sequence of points (a lattice).
Such exact discretization is found for an arbitrary lattice spacing.


title:
Formalized procedure of transition to classical limit in application to
  the Dirac equation

abstract:
  Classical model S{Dcl} of the Dirac particle S_D is constructed. S_D is the
dynamic system described by the Dirac equation. For investigation of S_D and
construction of S_{Dcl} one uses a new dynamic method: dynamic disquantization.
This relativistic purely dynamic procedure does not use principles of quantum
mechanics. The obtained classical analog S_{Dcl} is described by a system of
ordinary differential equations, containing the quantum constant as a
parameter. Dynamic equations for S_{Dcl} are determined by the Dirac equation
uniquely. The dynamic system S_{Dcl} has ten degrees of freedom and cannot be a
pointlike particle, because it has an internal structure. Internal degrees of
freedom appears to be described nonrelativistically. One discusses interplay
between the conventional axiomatic methods and the dynamical methods of the
quantum systems investigation. In particular, one discusses the reasons, why
the internal degrees of freedom of the Dirac particle and their nonrelativistic
character were not discovered during eighty years.


title: Energy Conversion of Fully Random Thermal Relaxation Times

abstract:
  Thermodynamic random processes in thermal systems are generally associated
with one or several relaxation times, the inverse of which are formally
homogeneous with energy. Here, we show in a precise way that the periodic
modification of relaxation times during temperature-constant thermodynamic
cycles can be thermodynamically beneficiary to the operator. This result holds
as long as the operator who adjusts relaxation times does not attempt to
control the randomness associated with relaxation times itself as a Maxwell
'demon' would do. Indirectly, our result also shows that thermal randomness
appears satisfactorily described within a conventional quantum-statistical
framework, and that the attempts advocated notably by Ilya Prigogine to go
beyond a Hilbert space description of quantum statistics do not seem justified
- at least according to the present state of our knowledge. Fundamental
interpretation of randomness, either thermal or quantum mechanical, is briefly
discussed.


title: Momentum Dependent Fundamental Action

abstract:
  The fundamental action is dependent on momentum. Some consequences are
presented for matter waves and scalar quantum field theory.


title: Computing K3 and CY n-fold Metrics

abstract:
  The derivative expnsion in the context of IIB string scattering compactified
on non-trivial K3 and other Calabi-Yau manifolds is formulated. The scattering
data in terms of automorphic functions can be inverted to find the these
metrics. The solutions are parameterized by the moduli information, and the
metrics may be found to any desired accuracy in derivatives. Metric information
to low orders in derivatives allows for a counting of curves inside the
manifold; in addition, the coefficients of these exponential terms via D-brane
wrappings are polynomials that may admit an invariant interpretation in
cohomology. An interesting case pertaining to M-theory compactifications is the
collection of seven-dimensional $G_2$ manifolds; they can also be obtained when
the moduli space degenerates into cases, such as a toroidal one or other limit
in which modular functions on the space are known. Note: this work was written
two years ago; the recipe without the explicit form of the scattering and
metrics is given.


title:
Phase-Locked, Low-Noise, Frequency Agile Titanium: Sapphire Lasers for
  Simultaneous Atom Interferometers

abstract:
  We demonstrate phase lock of two >1.6W Titanium:sapphire lasers with a phase
noise of -138dBc/Hz at 1MHz from the carrier, using an intra-cavity
electro-optic phase modulator. The residual phase variance is 2.5 10^(-8)rad^2
integrated from 1Hz to 10kHz. Instantaneous offset frequency steps of up to
4MHz are achieved within 200ns. Simultaneous atom interferometers can make full
use of this ultra-low phase noise in differential measurements by suppressing
common influences from vibration of optics.


title: Removing redundancy in relativistic quantum mechanics

abstract:
  It is proposed that the Dirac equation, as normally interpreted, incorporates
intrinsic redundancies whose removal necessarily leads to an enormous gain in
calculating power and physical interpretation. Streamlined versions of the
Dirac equation can be developed which remove the redundancies and singularities
from many areas of quantum physics while giving quantum representations to
specific particle states.


title:
Higher Order Harmonics of Modulational Instability Induced by Vacuum
  Fluctuations

abstract:
  We study the higher order harmonics of scalar modulational instability in the
regime where it arises spontaneously through amplification of vacuum
fluctuations. We obtain detailed predictions concerning the detunings,
intensities, growth rates and spectral widths of the harmonics. These
predictions are well verified by experimental results obtained by propagating
high intensity light pulses through optical fibers.


title: A possible approach to relativistic thermodynamics

abstract:
  Considering a system of non-interacting particles characterized by the number
N of its constituents and by its Kelvin temperature T, we reduce the
transformation of the Kelvin temperature to the transformation mass


title: The Upgraded D0 Detector

abstract:
  The D0 experiment enjoyed a very successful data-collection run at the
Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has
been upgraded to take advantage of improvements to the Tevatron and to enhance
its physics capabilities. We describe the new elements of the detector,
including the silicon microstrip tracker, central fiber tracker, solenoidal
magnet, preshower detectors, forward muon detector, and forward proton
detector. The uranium/liquid-argon calorimeters and central muon detector,
remaining from Run I, are discussed briefly. We also present the associated
electronics, triggering, and data acquisition systems, along with the design
and implementation of software specific to D0.


title: On Symmetry and Conserved Quantities in Classical Mechanics

abstract:
  This paper expounds the relations between continuous symmetries and conserved
quantities, i.e. Noether's ``first theorem'', in both the Lagrangian and
Hamiltonian frameworks for classical mechanics. This illustrates one of
mechanics' grand themes: exploiting a symmetry so as to reduce the number of
variables needed to treat a problem.
  I emphasise that, for both frameworks, the theorem is underpinned by the idea
of cyclic coordinates; and that the Hamiltonian theorem is more powerful. The
Lagrangian theorem's main ``ingredient'', apart from cyclic coordinates, is the
rectification of vector fields afforded by the local existence and uniqueness
of solutions to ordinary differential equations. For the Hamiltonian theorem,
the main extra ingredients are the asymmetry of the Poisson bracket, and the
fact that a vector field generates canonical transformations iff it is
Hamiltonian.


title: On the hydrino state of the relativistic hydrogen atom

abstract:
  The Klein-Gordon equation of the hydrogen atom has a low-lying eigenstate,
called hydrino state, with square integrable wavefunction. The corresponding
spinor solution of Dirac's equation is not square integrable. For this reason
the hydrino state has been rejected in the early days of quantum mechanics as
being unphysical. Maybe it is time to change opinion.


title: On Symplectic Reduction in Classical Mechanics

abstract:
  This paper expounds the modern theory of symplectic reduction in
finite-dimensional Hamiltonian mechanics. This theory generalizes the
well-known connection between continuous symmetries and conserved quantities,
i.e. Noether's theorem. It also illustrates one of mechanics' grand themes:
exploiting a symmetry so as to reduce the number of variables needed to treat a
problem. The exposition emphasises how the theory provides insights about the
rotation group and the rigid body. The theory's device of quotienting a state
space also casts light on philosophical issues about whether two apparently
distinct but utterly indiscernible possibilities should be ruled to be one and
the same. These issues are illustrated using ``relationist'' mechanics.


title: Dynamic Modeling of the Electric Transportation Network

abstract:
  We introduce a model for the dynamic self-organization of the electric grid.
The model is characterized by a conserved magnitude, energy, that can travel
following the links of the network to satisfy nodes' load. The load fluctuates
in time causing local overloads that drive the dynamic evolution of the network
topology. Our model displays a transition from a fully connected network to a
configuration with a non-trivial topology and where global failures are
suppressed. The most efficient topology is characterized by an exponential
degree distribution, in agreement with the topology of the real electric grid.
The model intrinsically presents self-induced break-down events, which can be
thought as representative of real black-outs.


title:
The Complex Network of Evolutionary Computation Authors: an Initial
  Study

abstract:
  EC paper authors form a complex network of co-authorship which is, by itself,
a example of an evolving system with its own rules, concept of fitness, and
patterns of attachment. In this paper we explore the network of authors of
evolutionary computation papers found in a major bibliographic database. We
examine its macroscopic properties, and compare it with other co-authorship
networks; the EC co-authorship network yields results in the same ballpark as
other networks, but exhibits some distinctive patterns in terms of internal
cohesion. We also try to find some hints on what makes an author a sociometric
star. Finally, the role of proceeding editorship as the origin of long-range
links in the co-authorship network is studied as well.


title:
Magnitude clustering and dynamical scaling in trigger models for
  earthquake forecasting

abstract:
  One of the main interests in seismology is the formulation of models able to
describe the clustering in time occurrence of earthquakes. Analysis of the
Southern California Catalog shows magnitude clustering in correspondence to
temporal clustering. Here we propose a dynamical scaling hypothesis in which
time is rescaled in terms of magnitude. This hypothesis is introduced in the
context of a generalized trigger model and gives account for clustering in time
and magnitude for earthquake occurrence. The model is able to generate a
synthetic catalog reproducing magnitude and inter-even time distribution of
thirty years California seismicity.


title: Motion of the Tippe Top : Gyroscopic Balance Condition and Stability

abstract:
  We reexamine a very classical problem, the spinning behavior of the tippe top
on a horizontal table. The analysis is made for an eccentric sphere version of
the tippe top, assuming a modified Coulomb law for the sliding friction, which
is a continuous function of the slip velocity $\vec v_P$ at the point of
contact and vanishes at $\vec v_P=0$. We study the relevance of the gyroscopic
balance condition (GBC), which was discovered to hold for a rapidly spinning
hard-boiled egg by Moffatt and Shimomura, to the inversion phenomenon of the
tippe top. We introduce a variable $\xi$ so that $\xi=0$ corresponds to the GBC
and analyze the behavior of $\xi$. Contrary to the case of the spinning egg,
the GBC for the tippe top is not fulfilled initially. But we find from
simulation that for those tippe tops which will turn over, the GBC will soon be
satisfied approximately. It is shown that the GBC and the geometry lead to the
classification of tippe tops into three groups: The tippe tops of Group I never
flip over however large a spin they are given. Those of Group II show a
complete inversion and the tippe tops of Group III tend to turn over up to a
certain inclination angle $\theta_f$ such that $\theta_f<\pi$, when they are
spun sufficiently rapidly. There exist three steady states for the spinning
motion of the tippe top. Giving a new criterion for stability, we examine the
stability of these states in terms of the initial spin velocity $n_0$. And we
obtain a critical value $n_c$ of the initial spin which is required for the
tippe top of Group II to flip over up to the completely inverted position.


title:
Electric quadrupole moment of the $4d ^{2}D_{5/2}$ state in
  $^{88}Sr^{+}$ and its role in an optical frequency standard

abstract:
  The electric quadrupole moment for the $4d ^2D_{5/2}$ state of
$\mathrm{^{88}Sr^+}$, one of the most important candidates for an optical
clock, has been calculated using the relativistic coupled-cluster theory. The
result of the calculation is presented and the important many-body
contributions are highlighted. The calculated electric quadrupole moment is
$(2.94\pm0.07)ea_{0}^{2}$, where $a_{0}$ is the Bohr radius and $e$ the
electronic charge while the measured value is $(2.6\pm0.3)ea_{0}^{2}$. This is
so far the most accurate determination of the electric quadrupole moment for
the above mentioned state.


title:
On a natural definition of the kilogram and the ampere: the objectives
  and consequences

abstract:
  We consider a recent proposal [1] to redefine the kilogram in terms of
natural constants. In our opinion, the main objective of the redefinition
should be to build such a version of the SI system in which the electric
measurements are possible with the highest accuracy in SI units, and not in
practical units as now. We emphasize that this objective can be achieved only
with a simultaneous redefinition of the kilogram and ampere. This redefinition
must be in terms of fixed values of the Planck constant h and the elementary
charge e. Certain details of the possible redefinition are considered.


title: Binary and Multivariate Stochastic Models of Consensus Formation

abstract:
  A current paradigm in computer simulation studies of social sciences problems
by physicists is the emergence of consensus. The question is to establish when
the dynamics of a set of interacting agents that can choose among several
options (political vote, opinion, cultural features, etc.) leads to a consensus
in one of these options, or when a state with several coexisting social options
prevail. We consider here stochastic dynamic models naturally studied by
computer simulations. We will first review some basic results for the voter
model. This is a binary option stochastic model, and probably the simplest
model of collective behavior. Next we consider a model proposed by Axelrod for
the dissemination of culture. This model can be considered as a multivariable
elaboration of the voter model dynamics.


title:
Local anisotropy and giant enhancement of local electromagnetic fields
  in fractal aggregates of metal nanoparticles

abstract:
  We have shown within the quasistatic approximation that the giant
fluctuations of local electromagnetic field in random fractal aggregates of
silver nanospheres are strongly correlated with a local anisotropy factor S
which is defined in this paper. The latter is a purely geometrical parameter
which characterizes the deviation of local environment of a given nanosphere in
an aggregate from spherical symmetry. Therefore, it is possible to predict the
sites with anomalously large local fields in an aggregate without explicitly
solving the electromagnetic problem. We have also demonstrated that the average
(over nanospheres) value of S does not depend noticeably on the fractal
dimension D, except when D approaches the trivial limit D=3. In this case, as
one can expect, the average local environment becomes spherically symmetrical
and S approaches zero. This corresponds to the well-known fact that in trivial
aggregates fluctuations of local electromagnetic fields are much weaker than in
fractal aggregates. Thus, we find that, within the quasistatics, the
large-scale geometry does not have a significant impact on local
electromagnetic responses in nanoaggregates in a wide range of fractal
dimensions. However, this prediction is expected to be not correct in
aggregates which are sufficiently large for the intermediate- and
radiation-zone interaction of individual nanospheres to become important.


title: Textos de Fisica para professores e estudantes--II

abstract: This paper has been withdrawn by the author.


title: LCDG4 and DigiSim - Simulation activities at NICADD/NIU

abstract:
  We present two software packages developed to support detector R&D studies
for the International Linear Collider. LCDG4 is a full-detector simulator that
provides energy deposits from particles traversing the sensitive volumes of the
detector. It has been extensively used within the American ILC community,
providing data for algorithm development and detector optimization studies.
DigiSim models real-life digitization effects, converting the idealized
response into simulated detector readout. It has many useful features to
improve the realism in modeling detector response. The main characteristics of
these two complementary packages are discussed.


title: A Hybrid Density Functional Study of Armchair Si and Ge Nanotubes

abstract:
  First principles calculations based on hybrid density functional theory have
been used to study the electronic and geometric properties of armchair silicon
and germanium nanotubes ranging from A (3, 3) through A (9, 9). The approach
used is the finite cluster approach with hydrogen termination to simulate the
effects of longer tubes. A detailed comparison of the structures and
stabilities of Si and Ge nanotubes has been performed and the dependence of the
HOMO- LUMO or band gaps on the tube diameters has been investigated. Silicon
nanotubes appear to be less-puckered and more stable compared to germanium
nanotubes. The largest silicon nanotube studied has a cohesive energy of
3.138eV/atom to be compared with the cohesive energy of 2.770eV/atom for the
corresponding germanium nanotube. Contrary to some published results in the
literature, silicon nanotubes do not appear to be metallic for the cases
studied in the armchair configuration.


title:
X-point collapse and saturation in the nonlinear tearing mode
  reconnection

abstract:
  We study the nonlinear evolution of the resistive tearing mode in slab
geometry in two dimensions. We show that, in the strongly driven regime (large
Delta'), a collapse of the X-point occurs once the island width exceeds a
certain critical value ~1/Delta'. A current sheet is formed and the
reconnection is exponential in time with a growth rate ~eta^1/2, where eta is
the resistivity. If the aspect ratio of the current sheet is sufficiently
large, the sheet can itself become tearing-mode unstable, giving rise to
secondary islands, which then coalesce with the original island. The saturated
state depends on the value of Delta'. For small Delta', the saturation
amplitude is ~Delta' and quantitatively agrees with the theoretical prediction.
If Delta' is large enough for the X-point collapse to have occured, the
saturation amplitude increases noticeably and becomes independent of Delta'.


title: A Count of Classical Field Theory Graphs

abstract:
  A generating function is derived that counts the number of diagrams in an
arbitrary scalar field theory. The number of graphs containing any number $n_j$
of $j$-point vertices is given. The count is also used to obtain the number of
classical graphs in gauge theory and gravity.


title: Long-term stabilization of the length of an optical reference cavity

abstract:
  To obtain a high degree of long-term length stabilisation of an optical
reference cavity, its free-spectral range is locked by means of an accurate and
stable frequency synthesizer. The locking scheme is twofold: a laser is locked
on the N$^{th}$ mode of a reference Fabry-Perot cavity and part of the laser
light is shifted in frequency to be in resonance with the (N+1)$^{th}$ mode of
the cavity. This shift is generated by an acousto-optical modulator (AOM)
mounted in a double-pass scheme, matching half of the free spectral range of
the reference cavity. The resulting absolute stabilization of the length of the
cavity reaches the 10$^{-11}$ level per second, limited by the lock transfer
properties and the frequency stability of the AOM control synthesizer.


title: Reversible Destruction of Dynamical Localization

abstract:
  Dynamical localization is a localization phenomenon taking place, for
example, in the quantum periodically-driven kicked rotor. It is due to subtle
quantum destructive interferences and is thus of intrinsic quantum origin. It
has been shown that deviation from strict periodicity in the driving rapidly
destroys dynamical localization. We report experimental results showing that
this destruction is partially reversible when the deterministic perturbation
that destroyed it is slowly reversed. We also provide an explanation for the
partial character of the reversibility.

categories: physics.atom-ph cond-mat.other nlin.CD quant-ph


title: Coherently tunable third-order nonlinearity in a nanojunction

abstract:
  A possibility of tuning the phase of the third-order Kerr-type nonlinear
susceptibility in a system consisting of two interacting metal nanospheres and
a nonlinearly polarizable molecule is investigated theoretically and
numerically. It is shown that by varying the relative inter-sphere separation,
it is possible to tune the phase of the effective nonlinear susceptibility
\chi^{(3)}(\omega;\omega,\omega,-\omega)$ in the whole range from 0 to $2\pi$.


title: Beam Test of a Segmented Foil SEM Grid

abstract:
  A prototype Secondary-electron Emission Monitor (SEM) was installed in the 8
GeV proton transport line for the MiniBooNE experiment at Fermilab. The SEM is
a segmented grid made with 5 um Ti foils, intended for use in the 120 GeV NuMI
beam at Fermilab. Similar to previous workers, we found that the full
collection of the secondary electron signal requires a bias voltage to draw the
ejected electrons cleanly off the foils, and this effect is more pronounced at
larger beam intensity. The beam centroid and width resolutions of the SEM were
measured at beam widths of 3, 7, and 8 mm, and compared to calculations.
Extrapolating the data from this beam test, we expect a centroid and width
resolutions of 20um and 25 um, respectively, in the NuMI beam which has 1 mm
spot size.


title:
Triangle for the entropic index q of non-extensive statistical mechanics
  observed by Voyager 1 in the distant heliosphere

abstract:
  Tsallis identified a set of numbers, the q-triplet, (qstat, qsen, qrel), for
a system described by nonextensive statistical mechanics. The deviation of the
q's from unity is a measure of the departure from thermodynamic equilibrium. We
present observations of the q-triplets derived from two sets of daily averages
of the magnetic field strength B observed by Voyager 1 in the solar wind near
40 A.U. during 1989 and near 85 A.U. during 2002, respectively. The results for
1989 do not differ significantly from those for 2002. We find qstat = 1.75,
qsen = -0.6, and qrel = 3.8.


title: The NuMI Neutrino Beam at Fermilab

abstract:
  The Neutrinos at the Main Injector (NuMI) facility at Fermilab began
operations in late 2004. NuMI will deliver an intense muon neutrino beam of
variable energy (2-20 GeV) directed into the Earth at 58 mrad for short (~1km)
and long (~700-900 km) baseline experiments. Several aspects of the design and
results from early commissioning runs are reviewed.


title: The tensor analytical relationships of Dirac's equation

abstract:
  Dirac's equation of the electron will be discussed by using quaternions as
the basis of a new formalism which seems to be very well adapted to the
problem. The transformation properties of the equations as well as the
invariant and covariant [bilinear] constructions of Dirac's theory are
developed uniformly and systematically. A method of obtaining a covariant
formulation of the equations using customary tensor calculus also offers itself
unequivocally if we duplicate the Dirac equations. (Editorial note: In this
paper Lanczos introduces his ``fundamental equation,'' Eq. (54), from which two
Dirac fields forming an isospin doublet, or two spin 1 fields of opposite
parities, derive.)


title: Laval Turbonozzle Dynamics

abstract:
  The results of computing experiments are presented for the steam and gas
stream motion in converging-diverging flow element called Laval nozzle and
applied in steam and gas turbines. In beginning the experiments had carried out
for Laval nozzle tested by Stodola and then for this turbonozzle various
modifications. Quantitative evaluation of the state and motion parameters of
the viscous compressible fluid and the metering characteristics of the flow
elements are given as well as physically adequate interpretation of the
obtained results is presented at the first time. The computing experiments are
carried out by means of VeriGas program-modeler composed on the base of a new
approach to the classical physics development in field of fluid motion.


title:
An optically activated cantilever using photomechanical effects in
  dye-doped polymer fibers

abstract:
  We report on what we believe is the first demonstration of an optically
activated cantilever due to photomechanical effects in a dye-doped polymer
optical fiber. The fiber is observed to bend when light is launched off-axis.
The displacement angle monotonically increases as a function of the distance
between the illumination point and the fiber axis, and is consistent with
differential light-induced length changes. The photothermal and
photo-reorientation mechanisms, each with its own distinct response time, are
proposed to explain the observed time dependence. The measured degree of
bending is consistent with a model that we have proposed which includes
coupling between photoisomerization and heating. Most importantly, we have
discovered that at high light intensity, a cooperative release of stress
results in cis-to-trans isomerization that yields a large and abrupt length
change.


title: Falling chains

abstract:
  The one-dimensional fall of a folded chain with one end suspended from a
rigid support and a chain falling from a resting heap on a table is studied.
Because their Lagrangians contain no explicit time dependence, the falling
chains are conservative systems. Their equations of motion are shown to contain
a term that enforces energy conservation when masses are transferred between
subchains. We show that Cayley's 1857 energy nonconserving solution for a chain
falling from a resting heap is incorrect because it neglects the energy gained
when a transferred link leaves a subchain. The maximum chain tension measured
by Calkin and March for the falling folded chain is given a simple if rough
interpretation. Other aspects of this falling folded chain are briefly
discussed.


title:
Differential Geometric and Topological methods with MHD and plasma
  physics

abstract:
  Non-solitonic examples of the application of geometrical and topological
methods in plasma physics and magnetohydrodynamics (MHD) are given. The first
example considers the generalization of magnetic helicity to gravitational
torsion loop. The second example considers also the application of this same
torsion loop metric to some problems of helical fields in MHD dynamo theory. In
the last example a Riemannian magnetic metric is given where the magnetic field
itself is present in the diagonal time-independent metric. In this example the
MHD equations are shown to be compatible to the geometrical Bianchi identity by
making use of Cartan's differential calculus formalism. The Riemann curvature
of the helical flow is also obtained.


title: Nucleon deformation and atomic spectroscopy

abstract:
  Recent ineleastic electron-proton scattering experiments have led to rather
accurate values for the N->Delta transition quadrupole moment Q(N->Delta).The
experimental results imply a prolate (cigar-shaped) intrinsic deformation of
the nucleon. The nonsphericity of the proton's charge distribution might be
seen in the spectrum of atomic hydrogen. The possibilities and limitations for
determining the geometric shape of the nucleon in an atomic physics experiment
are discussed.


title:
Critical threshold and dynamics of a general rumor model on complex
  networks

abstract:
  We derive mean-field equations that describe the dynamics of a general model
of rumor spreading on complex networks, and use analytical and numerical
solutions of these equations to examine the threshold behavior and dynamics of
the model on random graphs, uncorrelated scale-free networks and scale-free
networks with assortative degree correlations. We show that in both homogeneous
networks and random graphs the model exhibits a critical threshold in the rumor
spreading rate below which a rumor cannot propagate in the system. In the case
of scale-free networks, on the other hand, this threshold becomes vanishingly
small in the limit of infinite system size. We find that the initial rate at
which a rumor spreads is much higher in scale-free networks than in random
graphs, and that the rate at which the spreading proceeds on scale-free
networks is further increased when assortative degree correlations are
introduced. The impact of degree correlations on the final fraction of nodes
that ever hears a rumor, however, depends on the interplay between network
topology and the rumor spreading rate. Our results show that scale-free
networks are prone to the spreading of rumors, just as they are to the
spreading of infections. They are relevant to the spreading dynamics of chain
emails, viral advertising and large-scale data dissemination algorithms on the
Internet, the so-called gossip protocols.


title:
Dirac's wave mechanical theory of the electron and its field theoretical
  interpretation

abstract:
  Editorial note: In this lecture, held at the meeting of the Berlin Physical
Society, October 25, 1929, Lanczos discusses a nonlinear generalization of
Proca's equation (derived from his ``fundamental equation'') such that the mass
is multiplied by a scalar field function.


title:
Kolmogorov Complexity, String Information, Panspermia and the Fermi
  Paradox

abstract:
  Bit strings rather than byte files can be a mode of transmission both for
intelligent signals and for travels of extraterrestrial life. Kolmogorov
complexity, i.e. the minimal length of a binary coded string completely
defining a system, can then, due to its universality, become a key concept in
the strategy of the search of extraterrestrials. Evaluating, for illustration,
the Kolmogorov complexity of the human genome, one comes to an unexpected
conclusion that a low complexity compressed string - analog of Noah's ark -
will enable the recovery of the totality of terrestrial life. The recognition
of bit strings of various complexity up to incompressible Martin-L\"{o}f random
sequences, will require a different strategy for the analysis of the cosmic
signals. The Fermi paradox "Where is Everybody?" can be viewed under in the
light of such information panspermia, i.e. a Universe full of traveling life
streams.


title:
Phase diagram of a ternary mixture of cholesterol and saturated and
  unsaturated lipids calculated from a microscopic model

abstract:
  We employ a molecular model to study a ternary mixture of saturated lipid,
with tails of sixteen carbons, a mono unsaturated lipid with tails of eighteen
carbons, and cholesterol. The model, solved within mean-field theory, produces
several forms of phase diagrams depending upon the relative strengths of
interactions, but only one that shows the coexistence of two liquid phases
observed in experiment. The lipids in the phase rich in cholesterol are more
ordered than those in the other. The binary cholesterol, saturated lipid system
also exhibits liquid, liquid coexistence.


title: On the covariant formulation of Dirac's equation

abstract:
  As a continuation of previous investigations, the formalism used there is
extended to the case when an external electric field is present and the
covariant formulation is performed again. The equation system obtained allows
no restriction in the manifold of the quantities if an undesired
overdetermination is to be avoided. The combined appearance of the dual
formations also indicates an improbable internal properly of the system and
suggests that the underlying Dirac equation needs a modification. (Editorial
note: In this paper Lanczos continues to discuss his ``fundamental equation,''
from which two Dirac fields forming an isospin doublet, or two spin 1 fields of
opposite parities, derive.)


title:
The conservation laws in the field theoretical representation of Dirac's
  theory

abstract:
  We show that in the new description, Dirac's ``current vector'' is not
related to a vector but to a tensor: the ``stress-energy tensor.''
Corresponding to Dirac's conservation law, we have the conservation laws of
momentum and energy. The stress-energy tensor consists of two parts: an
``electromagnetic'' part, which has the same structure as the stress-energy
tensor of the Maxwell theory, and a ``mechanical'' part, as suggested by
hydrodynamics. The connection between these two tensors, which appears
organically here, eliminates the well-known contradictions inherent in the
dynamics of electron theory. (Editorial note: In this paper Lanczos continues
to discuss his ``fundamental equation,'' from which he consistently derives
Proca's equation and its stress-energy tensor.)


title: Chiral microstructures (spirals) fabrication by holographic lithography

abstract:
  We present an optical interference model to create chiral microstructures
(spirals) and its realization in photoresist using holographic lithography. The
model is based on the interference of six equally-spaced circumpolar linear
polarized side beams and a circular polarized central beam. The pitch and
separation of the spirals can be varied by changing the angle between the side
beams and the central beam. The realization of the model is carried out using
the 325 nm line of a He-Cd laser and spirals of sub-micron size are fabricated
in photoresist.


title: Polarization gaps in spiral photonic crystals

abstract:
  We studied the optical properties of a dielectric photonic crystal structure
with spirals arranged in a hexagonal lattice. The dielectric constant of the
material is 9 and the filling ratio is 15.2%. We found that this kind of
structure exhibits a significant polarization gap for light incident along the
axis of the spirals. The eigenmodes inside the polarization gap are right-hand
(left-hand) circularly polarized depending on the whether the spirals are
left-handed (right-handed). The transmission spectrum of a slab of such a
structure has been calculated and matches well with the analysis of the
eigenmodes.


title: Relativistic and correlation effects in atoms

abstract:
  This review article deals with some case studies of relativistic and
correlation effects in atomic systems. After a brief introduction to
relativistic many-electron theory, a number of applications ranging from
correlation energy to parity non-conservation in atoms are considered. There is
a special emphasis on relativistic coupled-cluster theory as most of the
results presented here are based on it.


title:
On Consistent and Calibrated Inference about the Parameters of Sampling
  Distributions

abstract:
  The theory of probability, based on very general rules referred to as the
Cox-Polya-Jaynes Desiderata, can be used both as a theory of random mass
phenomena and as a quantitative theory of plausible inference about the
parameters of sampling distributions. The existing applications of the
Desiderata must be extended in order to allow for consistent inferences in the
limit of complete a priori ignorance about the values of the parameters. Since
the limits of consistent quantitative inference from incomplete information can
clearly be established, the developed theory is necessarily an effective one.
It is interesting to note that when applying the Desiderata strictly, we find
no contradictions between the so-called Bayesian and frequentist schools of
inductive reasoning.


title: Numerical modeling of elastic waves across imperfect contacts

abstract:
  A numerical method is described for studying how elastic waves interact with
imperfect contacts such as fractures or glue layers existing between elastic
solids. These contacts have been classicaly modeled by interfaces, using a
simple rheological model consisting of a combination of normal and tangential
linear springs and masses. The jump conditions satisfied by the elastic fields
along the interfaces are called the "spring-mass conditions". By tuning the
stiffness and mass values, it is possible to model various degrees of contact,
from perfect bonding to stress-free surfaces. The conservation laws satisfied
outside the interfaces are integrated using classical finite-difference
schemes. The key problem arising here is how to discretize the spring-mass
conditions, and how to insert them into a finite-difference scheme: this was
the aim of the present paper. For this purpose, we adapted an interface method
previously developed for use with perfect contacts [J. Comput. Phys. 195 (2004)
90-116]. This numerical method also describes closely the geometry of
arbitrarily-shaped interfaces on a uniform Cartesian grid, at negligible extra
computational cost. Comparisons with original analytical solutions show the
efficiency of this approach.


title: Geo-neutrinos: a new probe of Earth's interior

abstract:
  In preparation to the experimental results which will be available in the
future, we study geo-neutrino production for different models of mantle
convection and composition. By using global mass balance for the Bulk Silicate
Earth, the predicted flux contribution from distant sources in the crust and in
the mantle is fixed within a total uncertainty of +-15%. We also discuss
regional effects, provided by subducting slabs or plumes near the detector. In
four years a five-kton detector operating at a site relatively far from nuclear
power plants can achieve measurements of the geo-neutrino signal accurate to
within +-5%. It will provide a crucial test of the Bulk Silicate Earth and a
direct estimate of the radiogenic contribution to terrestrial heat.


title: Formation of laser plasma channels in a stationary gas

abstract:
  The formation of plasma channels with nonuniformity of about +- 3.5% has been
demonstrated. The channels had a density of 1.2x10^19 cm-3 with a radius of 15
um and with length >= 2.5 mm. The channels were formed by 0.3 J, 100 ps laser
pulses in a nonflowing gas, contained in a cylindrical chamber. The laser beam
passed through the chamber along its axis via pinholes in the chamber walls. A
plasma channel with an electron density on the order of 10^18 - 10^19 cm-3 was
formed in pure He, N2, Ar, and Xe. A uniform channel forms at proper time
delays and in optimal pressure ranges, which depend on the sort of gas. The
influence of the interaction of the laser beam with the gas leaking out of the
chamber through the pinholes was found insignificant. However, the formation of
an ablative plasma on the walls of the pinholes by the wings of the radial
profile of the laser beam plays an important role in the plasma channel
formation and its uniformity. A low current glow discharge initiated in the
chamber slightly improves the uniformity of the plasma channel, while a high
current arc discharge leads to the formation of overdense plasma near the front
pinhole and further refraction of the laser beam. The obtained results show the
feasibility of creating uniform plasma channels in non-flowing gas targets.


title: N-Electron Giant Dipole States in Crossed Electric and Magnetic Fields

abstract:
  Multi-electron giant dipole resonances of atoms in crossed electric and
magnetic fields are investigated. Stationary configurations corresponding to a
highly symmetric arrangement of the electrons on a decentered circle are
derived, and a normal-mode and stability analysis are performed. A
classification of the various modes, which are dominated by the magnetic field
or the Coulomb interactions, is provided. Based on the MCTDH approach, we carry
out a six-dimensional wave-packet dynamical study for the two-electron
resonances, yielding in particular lifetimes of more than 0.1 $\mu$s for strong
electric fields.


title: Fundamental particles and their interactions

abstract:
  In this article the current understanding of fundamental particles and their
interactions is presented for the interested non-specialist, by adopting a
semi-historical path. A discussion on the unresolved problems is also
presented.


title:
Stock mechanics: energy conservation theory and the fundamental line of
  DJIA

abstract:
  DJIA is tested whether it can be described as a mechanical system conserving
total energy with K (=v*v/2) + U, where U is calculated as the negative of work
done by force obtained in terms of the second derivative of price, assuming
unit mass.


title:
Is E112 a relatively inert element? Benchmark relativistic correlation
  study of spectroscopic constants in E112H and its cation

abstract:
  We report the first results of relativistic correlation calculation of the
spectroscopic properties for the ground state of E112H and its cation in which
spin-orbit interaction is taken into account non-perturbatively. Studying the
properties of E112 (eka-Hg) is required for chemical identification of its
long-lived isotope, $^{283}$112. It is shown that appropriate accounting for
spin-orbit effects leads to dramatic impact on the properties of E112H whereas
they are not so important for E112H$^+$. The calculated equilibrium distance,
$R_e^{calc}=1.662$ A, in E112H is notably smaller than
$R_e^{expt}=(1.738\pm0.003)$ A and $R_e^{calc}=1.738$ A in HgH, whereas the
dissociation energy, $D_e^{calc}=0.42$ eV, in E112H is close to
$D_e^{expt}=0.46$ eV and $D_e^{calc}=0.41$ eV in HgH. These data are quite
different from $R_e^{NH}=1.829$ A and $D_e^{NH}=0.06$ eV obtained for E112H
within the scalar-relativistic Douglas-Kroll approximation [Nakajima and Hirao,
Chem. Phys. Lett., 329, 511 (2000)]. Our results indicate that E112 should not
be expected to be "more inert" than Hg in opposite to the results by other
authors.


title: An index to quantify an individual's scientific research output

abstract:
  I propose the index $h$, defined as the number of papers with citation number
higher or equal to $h$, as a useful index to characterize the scientific output
of a researcher.


title: Reconstruct the Hierarchical Structure in a Complex Network

abstract:
  A number of recent works have concentrated on a few statistical properties of
complex networks, such as the clustering, the right-skewed degree distribution
and the community, which are common to many real world networks. In this paper,
we address the hierarchy property sharing among a large amount of networks.
Based upon the eigenvector centrality (EC) measure, a method is proposed to
reconstruct the hierarchical structure of a complex network. It is tested on
the Santa Fe Institute collaboration network, whose structure is well known. We
also apply it to a Mathematicians' collaboration network and the protein
interaction network of Yeast. The method can detect significantly hierarchical
structures in these networks.

categories: physics.soc-ph cond-mat.stat-mech physics.bio-ph q-bio.MN


title: Correlations in Bipartite Collaboration Networks

abstract:
  Collaboration networks are studied as an example of growing bipartite
networks. These have been previously observed to have structure such as
positive correlations between nearest-neighbour degrees. However, a detailed
understanding of the origin of this phenomenon and the growth dynamics is
lacking. Both of these are analyzed empirically and simulated using various
models. A new one is presented, incorporating empirically necessary ingredients
such as bipartiteness and sublinear preferential attachment. This, and a
recently proposed model of team assembly both agree roughly with some empirical
observations and fail in several others.


title: Modernized conventional Pendulum Seismometer

abstract:
  With the right choice of sensor, a `simple' pendulum has great potential as a
seismometer with superior low frequency sensitivity.


title:
Spontaneous emergence of contrarian-like behaviour in an opinion
  spreading model

abstract:
  We introduce stochastic driving in the Sznajd model of opinion spreading.
This stochastic effect is meant to mimic a social temperature, so that agents
can take random decisions with a varying probability. We show that a stochastic
driving has a tremendous impact on the system dynamics as a whole by inducing
an order-disorder nonequilibrium phase transition. Interestingly, under certain
conditions, this stochastic dynamics can spontaneously lead to agents in the
system who are analogous to Galam's contarians.


title: Newtonian gravitational deflection of light revisited

abstract:
  The angle of deflection of a light ray by the gravitational field of the Sun,
at grazing incidence, is calculated by strict and straightforward classical
Newtonian means using the corpuscular model of light. The calculation is
presented in the historical and scientific contexts of Newton's {\it Opticks}
and of modern views of the problem.


title: Radiation reaction of a classical quasi-rigid extended particle

abstract:
  The problem of the self-interaction of a quasi-rigid classical particle with
an arbitrary spherically symmetric charge distribution is completely solved up
to the first order in the acceleration. No ad hoc assumptions are made. It is
shown that most of the puzzles that this problem has aroused are due to the
inertia of the negative pressure that equilibrates the electrostatic repulsion
inside the particle. When the inertia of pressure is taken into account the
dressed mass turns out to be the bare mass plus the electrostatic mass m=m_0 +
m_e. It is shown that a proper mechanical behaviour requires that m_0 > m_e/3.
This condition poses a lower bound on the radius that a particle of a given
bare mass and charge may have. The violation of this condition is the reason
why the Lorentz-Abraham-Dirac formula for the radiation reaction of a point
charge predicts unphysical motions that run away or violate causality. Provided
the mass condition is met the solutions of the exact equation of motion never
run away and conform to causality and energy and momentum conservation. When
the radius is much smaller than the wave-length of the radiated fields, but the
mass condition is still met, the exact expression reduces to the formula that
was advocated recently by Rohrlich.


title: Limitations of Nanotechnology for Atom Interferometry

abstract:
  Do van der Waals interactions determine the smallest nanostructures that can
be used for atom optics? This question is studied with regard to the problem of
designing an atom interferometer with optimum sensitivity to de Broglie wave
phase shifts. The optimum sensitivity to acceleration and rotation rates is
also considered. For these applications we predict that nanostructures with a
period smaller than 40 nm will cause atom interferometers to perform poorly
because van der Waals interactions adversely affect how nanostructure gratings
work as beam-splitters.


title: Oscillations in molecular motor assemblies

abstract:
  Autonomous oscillations in biological systems may have a biochemical origin
or result from an interplay between force-generating and visco-elastic
elements. In molecular motor assemblies the force-generating elements are
molecular engines and the visco-elastic elements are stiff cytoskeletal
polymers. The physical mechanism leading to oscillations depends on the
particular architecture of the assembly. Existing models can be grouped into
two distinct categories: systems with a delayed force activation and anomalous
force-velocity relations. We discuss these systems within phase plane analysis
known from the theory of dynamic systems and by adopting methods from control
theory, the Nyquist stability criterion.


title:
Ring Identification and Pattern Recognition in Ring Imaging Cherenkov
  (RICH) Detectors

abstract:
  An algorithm for identifying rings in Ring Imaging Cherenkov (RICH) detectors
is described. The algorithm is necessarily Bayesian and makes use of a
Metropolis-Hastings Markov chain Monte Carlo sampler to locate the rings. In
particular, the sampler employs a novel proposal function whose form is
responsible for significant speed improvements over similar methods. The method
is optimised for finding multiple overlapping rings in detectors which can be
modelled well by the LHbC RICH toy model described herein.


title: Modelling Aging Characteristics in Citation Networks

abstract:
  Growing network models with preferential attachment dependent on both age and
degree are proposed to simulate certain features of citation network noted in
\cite{red2}. In this directed network, a new node gets attached to an older
node with the probability $\sim K(k)f(t)$ where the degree and age of the older
node are $k$ and $t$ respectively. Several functional forms of $K(k)$ and
$f(t)$ have been considered. The desirable features of the citation network can
be reproduced with $K(k) \sim k^{-\beta}$ and $f(t) \sim \exp(\alpha t)$ with
$\beta =2.0$ and $\alpha = -0.2$ and with simple modifications in the growth
scheme.


title:
Lanczos - Einstein - Petiau: From Dirac's equation to nonlinear wave
  mechanics

abstract:
  In 1929 Lanczos showed how to derive Dirac's equation from a more fundamental
system that predicted that spin 1/2 particles should come in pairs. Today,
these pairs can unambiguously be interpreted as isospin doublets. From the same
fundamental equation, Lanczos derived also the correct form of the wave
equation of massive spin 1 particles that would be rediscovered in 1936 by
Proca.
  Lanczos's fundamental system was put in Lagrangian form and generalized in
1933 by Einstein and Mayer, who used the semivector instead of the quaternion
formalism. Although they not did study all possible solutions, Einstein and
Mayer showed that the doublets consisted of particles with different mass and
charge. In fact, there are two main classes of doublets: proton/neutron and
electron/neutrino pairs.


title: Perturbative Solution to D-terms in N=2 Models and Metrics

abstract:
  N=2 gauged non-linear sigma models are examined classically and their D-terms
are solved. The variation of the classical Lagrangian in order to solve for the
auxiliary fields is identical to integrating these modes functionally. The
latter is performed for the general quotient. The D-term solution is equivalent
to solving a coupled set of algebraic equations.


title: Parity nonconservation in Atomic Zeeman Transitions

abstract:
  We discuss the possibility of measuring nuclear anapole moments in atomic
Zeeman transitions and perform the necessary calculations. Advantages of using
Zeeman transitions include variable transition frequencies and the possibility
of enhancement of parity nonconservation effects.


title:
Generalizations of Kadanoff's solution of the Saffman-Taylor problem in
  a wedge

abstract:
  We consider a zero-surface-tension two-dimensional Hele-Shaw flow in an
infinite wedge. There exists a self-similar interface evolution in this wedge,
an analogue of the famous Saffman-Taylor finger in a channel, exact shape of
which has been given by Kadanoff. One of the main features of this evolution is
its infinite time of existence and stability for the Hadamard ill-posed
problem. We derive several exact solutions existing infinitely by generalizing
and perturbing the one by Kadanoff.


title:
Proposal for Cherenkov Time of Flight Technique with Picosecond
  Resolution

abstract:
  A new particle identification device for Jlab 12 GeV program is proposed. It
is based on the measurement of time information obtained by means of a new
photon detector and time measuring concept. The expected time measurement
precision for the Cherenkov time-of-flight detector is about or less than 10
picosecond for Cherenkov radiators with lengths less than 50 cm.


title: Systematic study of the $^{87}$Sr clock transition in an optical lattice

abstract:
  With ultracold $^{87}$Sr confined in a magic wavelength optical lattice, we
present the most precise study (2.8 Hz statistical uncertainty) to-date of the
$^1S_0$ - $^3P_0$ optical clock transition with a detailed analysis of
systematic shifts (20 Hz uncertainty) in the absolute frequency measurement of
429 228 004 229 867 Hz. The high resolution permits an investigation of the
optical lattice motional sideband structure. The local oscillator for this
optical atomic clock is a stable diode laser with its Hz-level linewidth
characterized across the optical spectrum using a femtosecond frequency comb.


title: Logical foundation of theoretical physics

abstract:
  This is the logical foundation for for Relativity Theory, Probability Theory,
and for Quantum Theory. Contents is the following:
  1 Introduction. 2 Classical logic. 3 Time and space. 3.1 Recorders. 3.2 Time.
3.3 Space. 3.4 Relativity. 4. Probability. 4.1 B-functions. 4.2 Independent
tests. 4.3 Function of probability. 4.4 Conditional probability. 4.5 Classical
probability 4.6 B-functions and classical propositional logic. 4.7 Consistency
of the probability function. 4.7.1 Nonstandard numbers. 4.7.2 Model. 5. Quantum
theory. 5.1 Events and the moving equations. 5.2 Rotations of the x5Ox4 system
and B-bosonn. 5.3 Masses. 5.4 The one-mass states, particles and antiparticles.
5.5 The two-masses states. 5.5.1 Neutrinno. 5.5.2 Electroweak transformations.
5.6 Rotations of the Cartesian coordinates system and quarrks. 5.7 Gustatory
pentads. 5.8 Two events. 5.9 The dimension of physical space. 5.10 The
events-probability interpretation of Quantum Theory. 6. Conclusion.


title: Absolute proof that hydrogen-antihydrogen oscillations occur in nature

abstract:
  Detecting H-antiH oscillations is intimately connected with the existence of
natural antiH. We detect natural H-antiH oscillations, generated by a classical
spin-free Coulomb quantum gap, which we calculate analytically without any
parameter. Oscillation times are much smaller than those predicted with the
Standard Model. These unprecedented results also remove the so-called problem
with matter-antimatter asymmetry in the Universe.


title: Noise-induced first-order transition in anti-tumor immunotherapy

abstract:
  We studied the single-variable dynamics model of the tumor growth. A
first-order phase transition induced by an additive noise is shown to reproduce
the main features of tumor growth under immune surveillance. The critical
average cells population has a power-law function relationship with the immune
coefficient.


title: Studies of Boosted Decision Trees for MiniBooNE Particle Identification

abstract:
  Boosted decision trees are applied to particle identification in the
MiniBooNE experiment operated at Fermi National Accelerator Laboratory
(Fermilab) for neutrino oscillations. Numerous attempts are made to tune the
boosted decision trees, to compare performance of various boosting algorithms,
and to select input variables for optimal performance.


title: Exact Solution for the Second Harmonic Generation in XFELs

abstract:
  The generation of harmonic radiation through a non-linear mechanism driven by
bunching at fundamental frequency is an important option in the operation of
high gain Free-Electron Lasers (FELs). The use of harmonic generation at a
large scale facility may result in achieving shorter radiation wavelengths for
the same electron beam energy. This paper describes a theory of second harmonic
generation in planar undulators with particular attention to X-Ray FELs
(XFELs). Our study is based on an exact analytical solution of Maxwell
equations, derived with the help of the Green's function method. On the
contrary, up-to-date theoretical understanding of the second harmonic
generation is only limited to some estimation of the total radiation power
based on the source part of the wave equation. Moreover, we find that such part
of the wave equation is presented with several incorrect manipulations among
which is the omission of an important contribution. Our work yields correct
parametric dependencies and specific predictions of additional properties such
as polarization, angular distribution of the radiation intensity and total
power. The most surprising prediction is the presence of a vertically polarized
part of the second harmonic radiation, whereas up-to-date understanding assumes
that the field is horizontally polarized. Altogether, this paper presents the
first correct theory of second harmonic generation for high gain FELs.


title:
Physical intuition and time-dependent generalization of the Coulomb and
  Biot-Savart laws

abstract:
  An analysis is performed of the role played by physical intuition in
expressing the electromagnetic field in terms of its sources in the
time-dependent case. The conclusion is that it is dangerous to dissociate
physical intuition from the mathematical description of the phenomena.


title:
A High Efficiency Ultra High Vacuum Compatible Flat Field Spectrometer
  for EUV Wavelengths

abstract:
  A custom, flat field, extreme ultraviolet EUV spectrometer built specifically
for use with low power light sources that operate under ultrahigh vacuum
conditions is reported. The spectral range of the spectrometer extends from 4
nm to 40 nm. The instrument optimizes the light gathering power and signal to
noise ratio while achieving good resolution. A detailed description of the
spectrometer and design considerations are presented, as well as a novel
procedure that could be used to obtain a synthetic wavelength calibration with
the aid of only a single known spectral feature. This synthetic wavelength
calibration is compared to a standard wavelength calibration obtained from
previously reported spectral lines of Xe, Ar and Ne ions recorded with this
spectrometer.


title:
Radioactivity Induced by Neutrons: a Thermodynamic Approach to Radiative
  Capture

abstract:
  When Enrico Fermi discovered slow neutrons, he accounted for their great
efficiency in inducing radioactivity by merely mentioning the well-known
scattering cross-section between neutrons and protons. He did not refer to
capture cross-section, at that early stage. It is put forward that a
thermodynamic approach to neutron-proton radiative capture then widely debated
might underlie his early accounts. Fermi had already met with a similar
approach, and repeatedly used it.


title: A model for the distribution of aftershock waiting times

abstract:
  In this work the distribution of inter-occurrence times between earthquakes
in aftershock sequences is analyzed and a model based on a non-homogeneous
Poisson (NHP) process is proposed to quantify the observed scaling. In this
model the generalized Omori's law for the decay of aftershocks is used as a
time-dependent rate in the NHP process. The analytically derived distribution
of inter-occurrence times is applied to several major aftershock sequences in
California to confirm the validity of the proposed hypothesis.


title:
Fundamental Limits of the Dispersion of the Two-Photon Absorption
  Cross-Section

abstract:
  We rigorously apply the sum rules to the sum-over-states expression to
calculate the fundamental limits of the dispersion of the two-photon absorption
cross-section. A comparison of the theory with the data suggests that the
truncated sum rules in the three-level model give a reasonable fundamental
limit. Our ansatz that the two photon absorption cross-section near the limit
must have only three dominant statesis is supported by a rigorous analytical
calculation that the resonant term gets smaller as more states are added. We
also find that the contributions of the non-explicitly resonant terms can not
be neglected when analyzing real molecules with many excited states, even near
resonance. However, puzzling as it may be, extrapolating an off-resonant result
to resonance using only the resonant term of the three-level model is shown to
be consistent with the exact result. In addition, the off-resonant
approximation is shown to scale logarithmically when compared with the full
three-level model. This scaling can be used to simplify the analysis of
measurements. We find that existing molecules are still far from the
fundamental limit; so, there is room for improvement. But, reaching the
fundamental limit would require precise control of the energy-level spacing,
independently of the transition dipole moments -- a task that does not appear
possible using today's synthetic approaches. So, we present alternative methods
that can still lead to substantial improvements which only require the control
of the transition moment to the first excited state. While it is best to
normalize measured two photon absorption cross-sections to the fundamental
limits when comparing molecules, we show that simply dividing by the square of
the number of electrons per molecule yields a good metric for comparison.


title:
Scientific and Financial Performance Measure : A Simultaneous Model to
  Evaluate Scientific Activities

abstract:
  An alternative model to measure simultaneously scientific and financial
performances of scientific activities is proposed. This mathematical model
focuses only on the final scientific outcomes in each fiscal year to gurantee
the objectivity. The model is suited for the purpose of immediate and
quantitative evaluation needed by policy makers to make decision in the
subsequent fiscal year. The model can be applied to any branches of science,
while it is also adjustable to varying macro-economic indicators. This enables
the policy makers to evaluate equally scientific activities in various fields
of science. It is argued that implementing the model could realize a fair,
transparent and objective reward and punishment system in any scientific
activities in order to improve both individual and institutional performances.
The model also enables an automatic evaluation embedded in any scientific
databases either in the local system or over the net.


title: CLIC Drive Beam and LHC Based Fel-Nucleus Collider

abstract:
  The feasibility of a CLIC-LHC based FEL-nucleus collider is investigated. It
is shown that the proposed scheme satisfies all requirements of an ideal photon
source for the Nuclear Resonance Fluorescence method. The physics potential of
the proposed collider is illustrated for a beam of Pb nuclei.

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


title: The Status of Turkic Accelerator Complex Proposal

abstract:
  Recently, the Turkic Accelerator Complex (TAC) is proposed as a regional
facility for accelerator based fundamental and applied research. The complex
will include linac on ring type electron-positron collider as a phi, charm and
tau factory, linac based free electron laser (FEL), ring based third generation
synchrotron radiation (SR) source and a few GeV proton accelerator. Preliminary
estimations show that integral luminosity of hundred inverse femto-barns per
year can be achieved for factory options. The FEL facility is planned to obtain
laser beam between IR and soft X-ray region. In addition, SR facility will
produce photon beams in UV and X-ray region. The proton accelerator will give
opportunity to produce muon and neutron beams for applied research. The current
status of the conceptual study of the complex is presented.

categories: physics.acc-ph hep-ex hep-ph physics.ins-det


title:
The Relations between Agent Performances and Their Intellective
  Abilities in Competing Systems

abstract:
  This paper studies the relations between agent performances and their
intellective abilities in mix-games in which there are two groups of agents:
one group plays a minority game, and the other plays a majority game. These two
groups have different historical memories and different time horizons. It is
found that these relations are greatly influenced by the configurations of
historical memories of the two groups.


title: System Efficiency vs. Individual Performance in Competing Systems

abstract:
  this paper addresses the issue of the relation between the system efficiency
and the individual performance with different combinations of agent memory
lengths in mix-game model which is an extension of minority game (MG). In
mix-game, there are two groups of agents; group1 plays the majority game, but
the group2 plays the minority game. The average winnings of agents can
represent the average individual performance and the volatility of a system can
represent the efficiency of the system. It is found the correlations between
the average winnings of agents and the medians of local volatilities are
different when agent memory lengths change with different combinations of
m1=m2, m1<m2=6 and m2<m1=6. This paper also gives some suggestions for
designing complex competing systems.


title:
Thermodynamics and equilibrium structure of Ne_38 cluster: Quantum
  Mechanics versus Classical

abstract:
  The equilibrium properties of classical LJ_38 versus quantum Ne_38
Lennard-Jones clusters are investigated. The quantum simulations use both the
Path-Integral Monte-Carlo (PIMC) and the recently developed
Variational-Gaussian-Wavepacket Monte-Carlo (VGW-MC) methods. The PIMC and the
classical MC simulations are implemented in the parallel tempering framework.
The VGW method is used to locate and characterize the low energy states of
Ne_38, which are then further refined by PIMC calculations. Unlike the
classical case, the ground state of Ne_38 is a liquid-like structure. Among the
several liquid-like states with energies below the two symmetric states (O_h
and C_5v), the lowest two exhibit strong delocalization over basins associated
with at least two classical local minima. Because the symmetric structures do
not play an essential role in the thermodynamics of Ne_38, the quantum heat
capacity is a featureless curve indicative of the absence of any structural
transformations. Good agreement between the two methods, VGW and PIMC, is
obtained.


title: Controlling collisions of ultracold atoms with dc electric fields

abstract:
  It is demonstrated that elastic collisions of ultracold atoms forming a
heteronuclear collision complex can be manipulated by laboratory practicable dc
electric fields. The mechanism of electric field control is based on the
interaction of the instantaneous dipole moment of the collision pair with
external electric fields. It is shown that this interaction is dramatically
enhanced in the presence of a p-wave shape or Feshbach scattering resonance
near the collision threshold, which leads to novel electric-field-induced
Feshbach resonances.


title:
A Simultaneous Model to measure Academic and Financial Performances of
  Scientific Activities

abstract:
  I propose a new model to measure simultaneously academic and financial
performances of scientific activities quantitatively. The tool is very simple
and can be applied to any branches of science, while it is also adjustable to
varying macroeconomic indicators. I argue that implementing the model could
realize a fair and objective decisionmaking and also reward and punishment
system in order to improve the individual and institutional performances in
scientific activities.


title: Multichannel quantum-defect theory for slow atomic collisions

abstract:
  We present a multichannel quantum-defect theory for slow atomic collisions
that takes advantages of the analytic solutions for the long-range potential,
and both the energy and the angular-momentum insensitivities of the short-range
parameters. The theory provides an accurate and complete account of scattering
processes, including shape and Feshbach resonances, in terms of a few
parameters such as the singlet and the triplet scattering lengths. As an
example, results for $^{23}$Na-$^{23}$Na scattering are presented and compared
close-coupling calculations.


title: Symmetry breaking from Lorentz transformation

abstract:
  Symmetry breaking is discussed in this paper which comes from the Lorentz
transformation of special relativity and changes our view that two relatively
moving bodies always have the relative speed equal in magnitude and opposite in
direction. An appeal was made for the test of Lorentz transformation in a
multimedia environment which has the fundamental significance that it may
reveal the origin of symmetry breaking in many physical phenomena.


title:
Geometry Optimization of Crystals by the Quasi-Independent Curvilinear
  Coordinate Approximation

abstract:
  The quasi-independent curvilinear coordinate approximation (QUICCA) method
[K. N\'emeth and M. Challacombe, J. Chem. Phys. {\bf 121}, 2877, (2004)] is
extended to the optimization of crystal structures. We demonstrate that QUICCA
is valid under periodic boundary conditions, enabling simultaneous relaxation
of the lattice and atomic coordinates, as illustrated by tight optimization of
polyethylene, hexagonal boron-nitride, a (10,0) carbon-nanotube, hexagonal ice,
quartz and sulfur at the $\Gamma$-point RPBE/STO-3G level of theory.


title:
Microscopic statistical description of classical matter around black
  holes

abstract:
  The problem of statistical description of classical matter, represented by a
N-body system of relativistic point particles falling into a black hole, is
investigated, adopting a classical framework. A covariant microscopic
statistical description is developed for the classical particle system by
introducing the definition of observer-related N-particle microscopic
distribution function and by suitably extending to general relativity the
concept of Gibbs microscopic entropy. The corresponding entropy production rate
is calculated taking into account the presence of an event horizon and proven
to obey, for N>>1, an exact microscopic H-theorem which holds for arbitrary
geometries.


title:
pn-CCDs in a Low-Background Environment: Detector Background of the CAST
  X-ray Telescope

abstract:
  The CAST experiment at CERN (European Organization of Nuclear Research)
searches for axions from the sun. The axion is a pseudoscalar particle that was
motivated by theory thirty years ago, with the intention to solve the strong CP
problem. Together with the neutralino, the axion is one of the most promising
dark matter candidates. The CAST experiment has been taking data during the
last two years, setting an upper limit on the coupling of axions to photons
more restrictive than from any other solar axion search in the mass range below
0.1 eV. In 2005 CAST will enter a new experimental phase extending the
sensitivity of the experiment to higher axion masses. The CAST experiment
strongly profits from technology developed for high energy physics and for
X-ray astronomy: A superconducting prototype LHC magnet is used to convert
potential axions to detectable X-rays in the 1-10 keV range via the inverse
Primakoff effect. The most sensitive detector system of CAST is a spin-off from
space technology, a Wolter I type X-ray optics in combination with a prototype
pn-CCD developed for ESA's XMM-Newton mission. As in other rare event searches,
background suppression and a thorough shielding concept is essential to improve
the sensitivity of the experiment to the best possible. In this context CAST
offers the opportunity to study the background of pn-CCDs and its long term
behavior in a terrestrial environment with possible implications for future
space applications. We will present a systematic study of the detector
background of the pn-CCD of CAST based on the data acquired since 2002
including preliminary results of our background simulations.


title:
Consumers don't play dice, influence of social networks and
  advertisements

abstract:
  Empirical data of supermarket sales show stylised facts that are similar to
stock markets, with a broad (truncated) Levy distribution of weekly sales
differences in the baseline sales [R.D. Groot, Physica A 353 (2005) 501]. To
investigate the cause of this, the influence of social interactions and
advertisements are studied in an agent-based model of consumers in a social
network. The influence of network topology was varied by using a small-world
network, a random network and a Barabasi-Albert network. The degree to which
consumers value the opinion of their peers was also varied. On a small-world
and random network we find a phase-transition between an open market and a
locked-in market that is similar to condensation in liquids. At the critical
point, fluctuations become large and buying behaviour is strongly correlated.
However, on the small world network the noise distribution at the critical
point is Gaussian, and critical slowing down occurs which is not observed in
supermarket sales. On a scale-free network, the model shows a transition
between a gas-like phase and a glassy state, but at the transition point the
noise amplitude is much larger than what is seen in supermarket sales. To
explore the role of advertisements, a model is studied where imprints are
placed on the minds of consumers that ripen when a decision for a product is
made. The correct distribution of weekly sales returns follows naturally from
this model, as well as the noise amplitude, the correlation time and
cross-correlation of sales fluctuations. For particular parameter values,
simulated sales correlation shows power law decay in time. The model predicts
that social interaction helps to prevent aversion, and that products are viewed
more positively when their consumption rate is higher.


title: The network of concepts in written texts

abstract:
  Complex network theory is used to investigate the structure of meaningful
concepts in written texts of individual authors. Networks have been constructed
after a two phase filtering, where words with less meaning contents are
eliminated, and all remaining words are set to their canonical form, without
any number, gender or time flexion. Each sentence in the text is added to the
network as a clique. A large number of written texts have been scrutinized, and
its found that texts have small-world as well as scale-free structures. The
growth process of these networks has also been investigated, and a universal
evolution of network quantifiers have been found among the set of texts written
by distinct authors. Further analyzes, based on shufling procedures taken
either on the texts or on the constructed networks, provide hints on the role
played by the word frequency and sentence length distributions to the network
structure. Since the meaningful words are related to concepts in the author's
mind, results for text networks may uncover patterns in communication and
language processes that occur in the mind.


title:
Numerical simulations of negative-index refraction in wedge-shaped
  metamaterials

abstract:
  A wedge-shaped structure made of split-ring resonators (SRR) and wires is
numerically simulated to evaluate its refraction behavior. Four frequency
bands, namely, the stop band, left-handed band, ultralow-index band, and
positive-index band, are distinguished according to the refracted field
distributions. Negative phase velocity inside the wedge is demonstrated in the
left-handed band and the Snell's law is conformed in terms of its refraction
behaviors in different frequency bands. Our results confirmed that negative
index of refraction indeed exists in such a composite metamaterial and also
provided a convincing support to the results of previous Snell's law
experiments.


title: Neighborhood properties of complex networks

abstract:
  A concept of neighborhood in complex networks is addressed based on the
criterion of the minimal number os steps to reach other vertices. This amounts
to, starting from a given network $R_1$, generating a family of networks
$R_\ell, \ell=2,3,...$ such that, the vertices that are $\ell$ steps apart in
the original $R_1$, are only 1 step apart in $R_\ell$. The higher order
networks are generated using Boolean operations among the adjacency matrices
$M_\ell$ that represent $R_\ell$. The families originated by the well known
linear and the Erd\"os-Renyi networks are found to be invariant, in the sense
that the spectra of $M_\ell$ are the same, up to finite size effects. A further
family originated from small world network is identified.


title:
Large-Area, Low-Noise, High Speed, Photodiode-Based Fluorescence
  Detectors with Fast Overdrive Recovery

abstract:
  Two large-area, low noise, high speed fluorescence detectors have been built.
One detector consists of a photodiode with an area of 28 mm x 28 mm and a low
noise transimpedance amplifier. This detector has a input light-equivalent
spectral noise density of less than 3 pW/Hz^1/2, can recover from a large
scattered light pulse within 10 us, and has a bandwidth of at least 900 kHz.
The second detector consists of a 16 mm diameter avalanche photodiode and a
low-noise transimpedance amplifier. This detector has an input light-equivalent
spectral noise density of 0.08 pW/Hz^1/2, also can recover from a large
scattered light pulse within 10 us, and has a bandwidth of 1 MHz.


title:
Trapped and Bound Classical States of an Electric Dipole in Magnetic
  Field

abstract:
  In the present work, we study the classical behavior of an electric dipole in
presence of an external uniform magnetic field. We derive equations and
constants of motion from the Lagrangian formulation. We obtain an infinitely
periodic effective potential that describes a rotational motion. The problem is
not directly separable in relative and center of mass variables; even though,
we are able to write the energy of the system as a function of an only term,
the relative variable. We define another constant of motion, which couples the
relative with the center of mass variables. We describe conditions for bound
states of the dipole. In addition, we discuss the problem in the approximation
of small oscillations. Finally, we explore the existence of a possible family
of trapped states in a region of the space where there are no classical turning
points.


title: E = mc^2. Or Is It? : A Comment on Manuscript astro-ph/0504486

abstract:
  Manuscript astro-ph/0504486 is a clear example of the fundamental conceptual
flaw that had persisted for the past 100 years. Namely, the failure to realize
that mass-energy equivalence, as applied to a propagating light particle
(photon), is only a special case of a more general law that encompasses both
photons and subluminal particles.


title: Focusing and correlation properties of white-light optical vortices

abstract:
  We generate double-charge white-light optical vortices by sending a
circularly polarized partially incoherent light through an uniaxial crystal. We
show that the generated polichromatic vortices are structurally stable, and
their correlation properties can be altered by the beam focusing, resulting in
changes of the vortex core visibility.