title:
Criticality of Electron-Nucleus Cusp Condition to Local Effective
  Potential Energy Theories

abstract:
  Local(multiplicative) effective potential energy theories of electronic
structure comprise the transformation of the Schr{\"o}dinger equation for
interacting fermi systems to model noninteracting fermi or bose systems whereby
the equivalent density and energy are obtained. By employing the integrated
form of the Kato electron-nucleus cusp condition, we prove that the effective
electron -interaction potential energy of these model fermions or bosons is
finite at a nucleus. The proof is general and valid for arbitrary system
whether it be atomic, molecular, or solid state, and for arbitrary state and
symmetry. This then provides justification for all prior work in the literature
based on the assumption of finiteness of this potential energy at a nucleus. We
further demonstrate the criticality of the electron-nucleus cusp condition to
such theories by example of the Hydrogen molecule. We show thereby that both
model system effective electron-interaction potential energies, as determined
from densities derived from accurate wave functions, will be singular at the
nucleus unless the wave function satisfies the electron-nucleus cusp condition.


title: Equation of Motion of an Electric Charge

abstract:
  The appearance of the time derivative of the acceleration in the equation of
motion (EOM) of an electric charge is studied. It is shown that when an
electric charge is accelerated, a stress force exists in the curved electric
field of the accelerated charge, and this force is proportional to the
acceleration. This stress force acts as a reaction force which is responsible
for the creation of the radiation (instead of the "radiation reaction force"
that actually does not exist at low velocities). Thus the initial acceleration
should be supplied as an initial condition for the solution of the EOM of an
electric charge. It is also shown that in certain cases, like periodic motions
of an electric charge, the term that includes the time derivative of the
acceleration, represents the stress reaction force.


title:
The electrostatic potential profile along a biased molecular wire: A
  model quantum mechanical calculation

abstract:
  We study the electrostatic potential of a molecular wire bridging two
metallic electrodes in the limit of weak contacts. With the use of a
tight-binding model including a fully three-dimensional treatment of the
electrostatics of the molecular junction, the potential is shown to be poorly
screened, dropping mostly along the entire molecule. In addition, we observe
pronounced Friedel oscillations that can be related to the breaking of
electron-hole symmetry. Our results are in semi-quantitative agreement with
recent state-of-the-art ab initio calculations and point to the need of a
three-dimensional treatment to properly capture the behavior of the
electrostatic potential. Based on these results, current-voltage curves are
calculated within the Landauer formalism. It is shown that Coulomb interaction
partially compensates the localization of the charges induced by the electric
field and consequently tends to suppress zones of negative differential
resistance.


title: Recombination of three ultracold fermionic atoms

abstract:
  Three-body recombination of identical, spin-polarized fermionic atoms in the
ultracold limit is investigated. The mechanisms for recombination are described
in terms of the ``scattering volume'' $V_p$ in the framework of the adiabatic
hyperspherical representation. We have calculated numerically the recombination
rate $K_3$ as a function of $V_p$ and have found that $K_3$ scales as
$|V_p|^{8/3}$ for small $|V_p|$. A comparison with experimental data is also
presented.


title:
Subthreshold dynamics of the neural membrane potential driven by
  stochastic synaptic input

abstract:
  In the cerebral cortex, neurons are subject to a continuous bombardment of
synaptic inputs originating from the network's background activity. This leads
to ongoing, mostly subthreshold membrane dynamics that depends on the
statistics of the background activity and of the synapses made on a neuron.
Subthreshold membrane polarization is, in turn, a potent modulator of neural
responses. The present paper analyzes the subthreshold dynamics of the neural
membrane potential driven by synaptic inputs of stationary statistics. Synaptic
inputs are considered in linear interaction. The analysis identifies regimes of
input statistics which give rise to stationary, fluctuating, oscillatory, and
unstable dynamics. In particular, I show that (i) mere noise inputs can drive
the membrane potential into sustained, quasiperiodic oscillations (noise-driven
oscillations), in the absence of a stimulus-derived, intraneural, or network
pacemaker; (ii) adding hyperpolarizing to depolarizing synaptic input can
increase neural activity (hyperpolarization-induced activity), in the absence
of hyperpolarization-activated currents.


title: Do we live in an anthropic universe?

abstract:
  I cast doubt upon the desired consistency between the anthropic principle and
modern cosmology.


title: Model for optical forward scattering by nonspherical raindrops

abstract:
  We describe a numerical model for the interaction of light with large
raindrops using realistic nonspherical drop shapes. We apply geometrical optics
and a Monte Carlo technique to perform ray traces through the drops. We solve
the problem of diffraction independently by approximating the drops with
areaequivalent ellipsoids. Scattering patterns are obtained for different
polarizations of the incident light. They exhibit varying degrees of asymmetry
and depolarization that can be linked to the distortion and thus the size of
the drops. The model is extended to give a simplified long-path integration.


title: Relativistic electronic dressing

abstract:
  We study the effects of the relativistic electronic dressing in
laser-assisted electron-hydrogen atom elastic collisions. We begin by
considering the case when no radiation is present. This is necessary in order
to check the consistency of our calculations and we then carry out the
calculations using the relativistic Dirac-Volkov states. It turns out that a
simple formal analogy links the analytical expressions of the differential
cross section without laser and the differential cross section in presence of a
laser field.


title: Angular dependence of synchrotron radiation intensity

abstract:
  The detailed analysis of angular dependence of the synchrotron radiation (SR)
is presented. In particular, we analyze the angular dependence of the integral
SR-intensity and peculiarities of the angular dependence of the first harmonics
SR. Studying spectral SR-intensities, we have discovered their unexpected
angular behavior, completely different from that of the integral SR-intensity.
Namely, for any given synchrotron frequency, maxima of the spectral
SR-intensities recede from the orbit plane with increasing particle energy.
Thus, in contrast with the integral SR-intensity, the spectral ones have the
tendency to deconcentrate themselves on the orbit plane.


title:
Rapid Determination of Multiple Reaction Pathways in Molecular Systems:
  The Soft-Ratcheting Algorithm

abstract:
  We discuss the ``soft-ratcheting'' algorithm which generates targeted
stochastic trajectories in molecular systems with scores corresponding to their
probabilities. The procedure, which requires no initial pathway guess, is
capable of rapidly determining multiple pathways between known states.
Monotonic progress toward the target state is not required. The soft-ratcheting
algorithm is applied to an all-atom model of alanine dipeptide, whose unbiased
trajectories are assumed to follow overdamped Langevin dynamics. All possible
pathways on the two-dimensional dihedral surface are determined. The associated
probability scores, though not optimally distributed at present, may provide a
mechanism for estimating reaction rates.


title:
Probability of fixation of an advantageous mutant in a viral
  quasispecies

abstract:
  The probability that an advantageous mutant rises to fixation in a viral
quasispecies is investigated in the framework of multi-type branching
processes. Whether fixation is possible depends on the overall growth rate of
the quasispecies that will form if invasion is successful, rather than on the
individual fitness of the invading mutant. The exact fixation probability can
only be calculated if the fitnesses of all potential members of the invading
quasispecies are known. Quasispecies fixation has two important
characteristics: First, a sequence with negative selection coefficient has a
positive fixation probability as long as it has the potential to grow into a
quasispecies with an overall growth rate that exceeds the one of the
established quasispecies. Second, the fixation probabilities of sequences with
identical fitnesses can nevertheless vary over many orders of magnitudes. Two
approximations for the probability of fixation are introduced. Both
approximations require only partial knowledge about the potential members of
the invading quasispecies. The performance of these two approximations is
compared to the exact fixation probability on a network of RNA sequences with
identical secondary structure.


title:
Radiation by a relativistic charged particle in self-wakefield in
  periodic structure

abstract:
  A new elementary mechanism of radiation due to the oscillatory character of a
radiation reaction force appearing when a relativistic charged particle moves
along a periodic structure without external fields is investigated. It is shown
that the non-synchronous spatial harmonics of Cherenkov-type radiation (CR) can
give rise to the oscillation of a particle which consequently generates
undulator-type radiation (UR). In the spectral region, where the diffraction of
generated waves is essential, the radiation manifests itself in the coherent
interference of CR and UR. A pure undulator -type radiation takes place only in
the wavelength range where the wave diffraction can be neglected. In the case
of coherent UR by a bunch of N electrons, the UR power is proportional to N in
the forth degree.


title:
Superluminal Localized Solutions to the wave equation, in (vacuum or)
  dispersive media, for arbitrary frequencies and with adjustable bandwidth

abstract:
  In this paper we set forth new exact analytical Superluminal localized
solutions to the wave equation for arbitrary frequencies and adjustable
bandwidth. The formulation presented here is rather simple, and its results can
be expressed in terms of the ordinary, so-called "X-shaped waves". Moeover, by
the present formalism we obtain the first analytical localized Superluminal
approximate solutions which represent beams propagating in dispersive media.
Our solutions may find application in different fields, like optics,
microwaves, radio waves, and so on. [PACS nos.: 03.50.De ; 41.20.Jb ; 83.50.Vr
; 62.30.+d ; 43.60.+d ; 91.30.Fn ; 04.30.Nk ; 42.25.Bs ; 46.40.Cd ; 52.35.Lv.
Keywords: Wave equation; Wave propagation; Optics; Localized beams;
Superluminal waves; Bessel beams; X-shaped waves; Acoustics; Mechanical waves;
Dispersion compensation; Seismology; Geophysics; Gravitational Waves;
Elementary particle physics].


title:
Superluminal Localized Solutions to Maxwell Equations propagating along
  a waveguide: The finite-energy case

abstract:
  In a previous paper of ours [Phys. Rev. E64 (2001) 066603, e-print
physics/0001039] we have shown localized (non-evanescent) solutions to Maxwell
equations to exist, which propagate without distortion with Superluminal speed
along normal-sized waveguides, and consist in trains of "X-shaped" beams. Those
solutions possessed therefore infinite energy. In this note we show how to
obtain, by contrast, finite-energy solutions, with the same localization and
Superluminality properties. [PACS nos.: 41.20.Jb; 03.50.De; 03.30.+p; 84.40.Az;
42.82.Et. Keywords: Wave-guides; Localized solutions to Maxwell equations;
Superluminal waves; Bessel beams; Limited-dispersion beams; Finite-energy
waves; Electromagnetic wavelets; X-shaped waves; Evanescent waves;
Electromagnetism; Microwaves; Optics; Special relativity; Localized acoustic
waves; Seismic waves; Mechanical waves; Elastic waves; Guided gravitational
waves.]


title: Zipf's Law in Gene Expression

abstract:
  Using data from gene expression databases on various organisms and tissues,
including yeast, nematodes, human normal and cancer tissues, and embryonic stem
cells, we found that the abundances of expressed genes exhibit a power-law
distribution with an exponent close to -1, i.e., they obey Zipf's law.
Furthermore, by simulations of a simple model with an intra-cellular reaction
network, we found that Zipf's law of chemical abundance is a universal feature
of cells where such a network optimizes the efficiency and faithfulness of
self-reproduction. These findings provide novel insights into the nature of the
organization of reaction dynamics in living cells.

categories: physics.bio-ph cond-mat.dis-nn nlin.AO q-bio


title:
Superluminal X-shaped beams propagating without distortion along a
  coaxial guide

abstract:
  In a previous paper [Phys. Rev. E64 (2001) 066603; e-print physics/0001039],
we showed that localized Superluminal solutions to the Maxwell equations exist,
which propagate down (non-evanescence) regions of a metallic cylindrical
waveguide. In this paper we construct analogous non-dispersive waves
propagating along coaxial cables. Such new solutions, in general, consist in
trains of (undistorted) Superluminal "X-shaped" pulses. Particular attention is
paid to the construction of finite total energy solutions. Any results of this
kind may find application in the other fields in which an essential role is
played by a wave-equation (like acoustics, geophysics, etc.). [PACS nos.:
03.50.De; 41.20;Jb; 83.50.Vr; 62.30.+d; 43.60.+d; 91.30.Fn; 04.30.Nk; 42.25.Bs;
46.40.Cd; 52.35.Lv. Keywords: Wave equations; Wave propagation; Localized
beams; Superluminal waves; Coaxial cables; Bidirectional decomposition; Bessel
beams; X-shaped waves; Maxwell equations; Microwaves; Optics; Special
relativity; Coaxial metallic waveguides; Acoustics; Seismology; Mechanical
waves; Elastic waves; Guided gravitational waves.]


title: Electric field effect on positronium formation in liquids

abstract:
  The comparison of different models (the Ore, spur and blob models) of
positronium (Ps) formation is presented. Because in molecular media Ps is
formed in the terminal positron blob and not in an ordinary spur, the
application of the blob model seems to be the most adequate. We extend this
model for consideration of the Ps formation in the presence of external
electric field ($<100$ kV/cm). In the simplified limiting case, this approach
provides a formula similar to the Onsager one for the geminate recombination
probability. The influence of ion-electron recombination and other intrablob
processes on Ps formation is taken into account. The role of quasifree
positronium in Ps formation process is discussed.


title:
The Determination of Microscopic Surface Tension of Liquids with a
  Curved Interphase Boundary by Means of Positron Spectroscopy

abstract:
  The method for determination the microscopic surface tension $\sigma(R)$ of
nanobubbles is developed based on the new elaboration of the positronium bubble
model. In contrast to existing structureless Ps bubble models, our version
contains experimentally known molecular characteristics of liquids. The
relationship, similar to Tolman's equation, between $\sigma(R)$ and the radius
$R$ of the Ps bubble is derived on a microscopic basis. Numerical values for
$\sigma(R)$ are determined for a large number of liquids and liquified gases.
The results are in agreement with the theoretical expectations and independent
evaluations, available in literature.


title: General Relativity Requires Absolute Space and Time

abstract:
  We examine two far-reaching and somewhat heretic consequences of General
Relativity. (i) It requires a cosmology which includes a preferred rest frame,
absolute space and time. (ii) A rotating universe and time travel are strict
solutions of General Relativity.


title: Lochlainn O'Raifeartaigh, Fluids, and Noncommuting Fields

abstract:
  Lochlainn O'Raifeartaigh and his work are recalled; the connection between
fluid mechanics -- his last research topic -- and noncommuting gauge fields is
explained.

categories: physics.hist-ph hep-th math-ph math.MP physics.flu-dyn


title: The Possible Solution to the Two-Slit Electron Interference Pattern

abstract:
  To this day, the two-slit electron interference pattern remains shrouded in
an inordinate mystery. It continues to defy a logical and rational explanation.
This paper will postulate a new "characteristic" pertaining to the electron. If
this characteristic is correct, the mystery of the two-slit pattern will be
eliminated. Furthermore, the theory is testable. Fundamentally, the tests
entail running the experiment in slightly different ways. If the theory is
correct, we shall see patterns that we've never previously witnessed.


title: An alternate way to obtain the aberration expansion in Helmholtz Optics

abstract:
  Exploiting the similarities between the Helmholtz wave equation and the
Klein-Gordon equation, the former is linearized using the Feschbach-Villars
procedure used for linearizing the Klein-Gordon equation. Then the
Foldy-Wouthuysen iterative diagonalization technique is applied to obtain a
Hamiltonian description for a system with varying refractive index. Besides
reproducing all the traditional quasiparaxial terms, this method leads to
additional terms, which are dependent on the wavelength, in the optical
Hamiltonian. This alternate prescription to obtain the aberration expansion is
applied to the axially symmetric graded index fiber. This results in the
wavelength-dependent modification of the paraxial behaviour and the aberration
coefficients. Explicit expression for the modified coefficients of the
aberration to third-order are presented. Sixth and eighth order Hamiltonians
are derived for this system.

categories: physics.optics physics.acc-ph physics.gen-ph quant-ph


title: Quantum chaos in optical systems: The annular billiard

abstract:
  We study the dielectric annular billiard as a quantum chaotic model of a
micro-optical resonator. It differs from conventional billiards with hard-wall
boundary conditions in that it is partially open and composed of two dielectric
media with different refractive indices. The interplay of reflection and
transmission at the different interfaces gives rise to rich dynamics of
classical light rays and to a variety of wave phenomena. We study the ray
propagation in terms of Poincare surfaces of section and complement it with
full numerical solutions of the corresponding wave equations. We introduce and
develop an S-matrix approach to open optical cavities which proves very
suitable for the identification of resonances of intermediate width that will
be most important in future applications like optical communication devices. We
show that the Husimi representation is a useful tool in characterising
resonances and establish the ray-wave correspondence in real and phase space.
While the simple ray picture provides a good qualitative description of certain
system classes, only the wave description reveals the quantitative details.


title: Dynamics of stochastic systems and peculiarities of measurements in them

abstract:
  One calls attention to the fact that the stochastic physical systems are not
random completely. They have both random and regular components of their
evolution. Dynamic system is considered to be a special case of physical system
with vanishing stochastic component of evolution. Mathematical technique for
description of regular evolution component of physical systems (stochastic and
deterministic) is constructed. The regular component of the system S evolution
is described explicitly by the statistical average system <S>, which is a
continuous dynamic system. The action for <S> is reduced to the form of the
action for a set of interacting identical deterministic systems S_d. The form
of interaction of S_d describes implicitly the character of the stochastic
component of S evolution. Interplay between the physical system S and the
statistical average system <S> in the measurement process is discussed. There
are at least two different kind of measurement: single measurements
(S-measurements) connected with measurements in S and mass measurements
(M-measurements) connected with measurements in <S>. Conventional
identification of S-measurement and M-measurement is a source of many
misunderstandings and paradoxes.


title:
A modular PC based silicon microstrip beam telescope with high speed
  data acquisition

abstract:
  A PC based high speed silicon microstrip beam telescope consisting of several
independent modules is presented. Every module contains an AC-coupled double
sided silicon microstrip sensor and a complete set of analog and digital signal
processing electronics. A digital bus connects the modules with the DAQ PC. A
trigger logic unit coordinates the operation of all modules of the telescope.
The system architecture allows easy integration of any kind of device under
test into the data acquisition chain. Signal digitization, pedestal correction,
hit detection and zero suppression are done by hardware inside the modules, so
that the amount of data per event is reduced by a factor of 80 compared to
conventional readout systems. In combination with a two level data acquisition
scheme, this allows event rates up to 7.6 kHz. This is a factor of 40 faster
than conventional VME based beam telescopes while comparable analog performance
is maintained achieving signal to noise ratios of up to 70:1. The telescope has
been tested in the SPS testbeam at CERN. It has been adopted as the reference
instrument for testbeam studies for the ATLAS pixel detector development.


title:
Notes on Landauer's principle, Reversible Computation and Maxwell's
  Demon

abstract:
  Landauer's principle, often regarded as the foundation of the thermodynamics
of information processing, holds that any logically irreversible manipulation
of information, such as the erasure of a bit or the merging of two computation
paths, must be accompanied by a corresponding entropy increase in
non-information bearing degrees of freedom of the information processing
apparatus or its environment. Conversely, it is generally accepted that any
logically reversible transformation of information can in principle be
accomplished by an appropriate physical mechanism operating in a
thermodynamically reversible fashion. These notions have sometimes been
criticized either as being false, or as being trivial and obvious, and
therefore unhelpful for purposes such as explaining why Maxwell's Demon cannot
violate the Second Law of thermodynamics. Here I attempt to refute some of the
arguments against Landauer's principle, while arguing that although in a sense
it is indeed a trivial and obvious restatement of the Second Law, it still has
considerable pedagogic and explanatory power, especially in the context of
other influential ideas in 19'th and 20'th century physics. Similar arguments
have been given by Jeffrey Bub [arXiv:quant-ph/0203017].


title:
The Development and Study of High-Position Resolution (50 micron) RPCs
  for Imaging X-rays and UV photons

abstract:
  Nowadays, commonly used Resistive Plate Chambers (RPCs) have counting rate
capabilities of ~10E4Hz/cm2 and position resolutions of ~1cm. We have developed
small prototypes of RPCs (5x5 and 10x10cm2) having rate capabilities of up to
10E7Hz/cm2 and position resolutions of 50 micron("on line" without application
of any treatment method like "center of gravity"). The breakthrough in
achieving extraordinary rate and position resolutions was only possible after
solving several serious problems: RPC cleaning and assembling technology,
aging, spurious pulses and afterpulses, discharges in the amplification gap and
along the spacers. High-rate, high-position resolution RPCs can find a wide
range of applications in many different fields, for example in medical imaging.
RPCs with the cathodes coated by CsI photosensitive layer can detect
ultraviolet photons with a position resolution that is better than ~30 micron.
Such detectors can also be used in many applications, for example in the focal
plane of high resolution vacuum spectrographs or as image scanners.


title:
Beyond the RICH: Innovative Photosensitive Gaseous Detectors for new
  Fields of Applications

abstract:
  We have developed and successfully used several innovative designs of
detectors with solid photocathodes. The main advantage of these detectors is
that rather high gains (>10E4) can be achieved in a single multiplication step.
This is possible by, for instance, exploiting the secondary electron
multiplication and limiting the energy of the steamers by distributed
resistivity. The single step approach also allows a very good position
resolution to be achieved in some devices: 50 micron on line without applying
any treatment method (like center of gravity). The main focus of our report is
new fields of applications for these detectors and the optimization of their
designs for such purposes.


title: Large Scale Weather Control Using Nuclear Reactors

abstract:
  It is pointed out that controlled release of thermal energy from fission type
nuclear reactors can be used to alter weather patterns over significantly large
geographical regions. (1) Nuclear heat creates a low pressure region, which can
be used to draw moist air from oceans, onto deserts. (2) Creation of low
pressure zones over oceans using Nuclear heat can lead to Controlled Cyclone
Creation (CCC).(3) Nuclear heat can also be used to melt glaciers and control
water flow in rivers.

categories: physics.ao-ph physics.flu-dyn physics.gen-ph physics.geo-ph


title: Transient growth in Taylor-Couette flow

abstract:
  Transient growth due to non-normality is investigated for the Taylor-Couette
problem with counter-rotating cylinders as a function of aspect ratio eta and
Reynolds number Re. For all Re < 500, transient growth is enhanced by
curvature, i.e. is greater for eta < 1 than for eta = 1, the plane Couette
limit. For fixed Re < 130 it is found that the greatest transient growth is
achieved for eta between the Taylor-Couette linear stability boundary, if it
exists, and one, while for Re > 130 the greatest transient growth is achieved
for eta on the linear stability boundary. Transient growth is shown to be
approximately 20% higher near the linear stability boundary at Re = 310, eta =
0.986 than at Re = 310, eta = 1, near the threshold observed for transition in
plane Couette flow. The energy in the optimal inputs is primarily meridional;
that in the optimal outputs is primarily azimuthal. Pseudospectra are
calculated for two contrasting cases. For large curvature, eta = 0.5, the
pseudospectra adhere more closely to the spectrum than in a narrow gap case,
eta = 0.99.


title: Vibrational Stability of NLC Linac accelerating structure

abstract:
  The vibration of components of the NLC linac, such as accelerating structures
and girders, is being studied both experimentally and analytically. Various
effects are being considered including structural resonances and vibration
caused by cooling water in the accelerating structure. This paper reports the
status of ongoing work.


title: Vibrational Stability of NLC Linac and Final Focus Components

abstract:
  Vertical vibration of linac components (accelerating structures, girders and
quadrupoles) in the NLC has been studied experimentally and analytically.
Effects such as structural resonances and vibration caused by cooling water
both in accelerating structures and quadrupoles have been considered.
Experimental data has been compared with analytical predictions and simulations
using ANSYS. A design, incorporating the proper decoupling of structure
vibrations from the linac quadrupoles, is being pursued.


title:
Determination of Molecules Distribution of the Impurity in Monocrystal
  of the Solid Solution by the Method of Raman Effect

abstract:
  Distribution of centrosymmetrical molecules of an impurity (p-diclorobenzene)
in monocrystals of solid solutions in two different matrixes with
centrosymmetrical (p-dibrombenzene) and noncentrosymmetrical
(p-bromchlorbenzene) molecules by the method of a Raman Effect is determined.


title: Classical Aberration And Obliquation

abstract:
  This is the first of several monographs to be devoted to the optics of
accelerated systems. They are being published for the benefit of those who may
wish to have another way of looking at kineoptical problems, and also to
demonstrate that the laws of optics are unwavering in their support of the view
that extragalactic redshifts need not be velocity doppler shifts nor
cosmological recession shifts. In the latter context the first few monographs
of the series may be viewed as providing a basis for the demonstration to be
given in a latter monograph.


title: Electro-Mechanical Resonant Magnetic Field Sensor

abstract:
  We describe a new type of magnetic field sensor which is termed an
Electro-Mechanical Resonant Sensor (EMRS). The key part of this sensor is a
small conductive elastic element with low damping rate and therefore a high Q
fundamental mode of frequency $f_1$. An AC current is driven through the
elastic element which, in the presence of a magnetic field, causes an AC force
on the element. When the frequency of the AC current matches the resonant
frequency of the element, maximum vibration of the element occurs and this can
be measured precisely by optical means. We have built and tested a model sensor
of this type using for the elastic element a length of copper wire of diameter
0.030 mm formed into a loop shape. The wire motion was measured using a light
emitting diode photo-transistor assembly. This sensor demonstrated a
sensitivity better than 0.001G for an applied magnetic field of $ \sim 1$G and
a good selectivity for the magnetic field direction. The sensitivity can be
easily improved by a factor of $\sim 10 - 100$ by more sensitive measurement of
the elastic element motion and by having the element in vacuum to reduce the
drag force.


title: The physics of stone skipping

abstract:
  The motion of a stone skimming over a water surface is considered. A
simplified description of the collisional process of the stone with water is
proposed. The maximum number of bounces is estimated by considering both the
slowing down of the stone and its angular stability. The conditions for a
successful throw are discussed.


title: Autopsy on an RF-Processed X-band Travelling Wave Structure

abstract:
  In an effort to locate the cause(s) of high electric-field breakdown in
x-band accelerating structures, we have cleanly-autopsied (no debris added by
post-operation structure disassembly) an RF-processed structure. Macroscopic
localization provided operationally by RF reflected wave analysis and acoustic
sensor pickup was used to connect breakdowns to autopsied crater damage areas.
Surprisingly, the microscopic analyses showed breakdown craters in areas of low
electric field. High currents induced by the magnetic field on sharp corners of
the input coupler appears responsible for the extreme breakdown damage
observed.


title: Mechanical and electrical noise in the PVLAS experiment

abstract:
  PVLAS is an experiment which aims at the direct detection of photon-field
scattering: it employs optical methods and a large rotating superconducting
magnet, and its large, compact structure is affected by both mechanical and
electrical noises. This paper introduces briefly the data analysis methods used
in the experiment and summarizes the mechanical and electrical noise situation.


title: Borromean molecules

abstract:
  For some values of the constituent masses m_i, the hydrogen-like molecule
(m_1^+,m_2^+,m_3^-,m_4^-) is stable with respect to spontaneous dissociation
into two neutral atoms, while none of its three-body subsystems such as
(m_1^+,m_2^+,m_3^-) is stable. This occurs in particular in the neighbourhood
of the (M^+,m^+,M^-,m^-) configuration with M/m=2, as for instance for the
molecule (p,d,\bar{p},\bar{d}) involving an antiproton and an antideuteron.


title: Inelastic Collision Rates of Trapped Metastable Hydrogen

abstract:
  We report the first detailed decay studies of trapped metastable (2S)
hydrogen. By two-photon excitation of ultracold H samples, we have produced
clouds of at least 5x10^7 magnetically trapped 2S atoms at densities greater
than 4x10^10 cm^-3 and temperatures below 100 \muK. We derive experimental
values for the total 2S-2S two-body loss rate constant in this temperature
regime. Our results are in the range of recent theoretical calculations. We
also find experimental upper limits on the rate constant for loss due to
inelastic 1S-2S collisions.


title:
Modeling of the time-resolved vibronic spectra of polyatomic molecules:
  the formulation of the problem and analysis of kinetic equations

abstract:
  A semiempirical parametric method is proposed for modeling three-dimensional
(time-resolved) vibronic spectra of polyatomic molecules. The method is based
on the use of the fragment approach in the formation of molecular models for
excited electronic states and parametrization of these molecular fragments by
modeling conventional (one-dimensional) absorption and fluorescence spectra of
polyatomic molecules. All matrix elements that are required for calculation of
the spectra can be found by the methods developed. The time dependencies of the
populations of a great number (>10^3) of vibronic levels can be most
conveniently found by using the iterative numerical method of integration of
kinetic equations. Convenient numerical algorithms and specialized software for
PC are developed. Computer experiments showed the possibility of the real-time
modeling of three-dimensional spectra of polyatomic molecules containing
several tens of atoms.


title:
Simulation of Time-Resolved Vibronic Spectra and the possibility of
  analyzing molecules with similar apectral properties

abstract:
  The possibility of using time-resolved vibronic spectroscopy for spectral
analysis of mixtures of chemical compounds with similar optical properties,
when traditional methods are inefficient, is demonstrated by using the method
of computer simulation. The analysis is carried out by the example of molecules
of a series of polyenes (butadiene, hexatraene, octatetraene, decapentaene, and
decatetraene), their various cis- and trans-rotational isomers, and
phenyl-substituted polyenes. Ranges of relative concentrations of molecules
similar in their spectral properties, where reliable interpretation of
time-resolved spectra of mixtures and both qualitative and quantitative
analyses are possible, are determined. The use of computer simulation methods
for oprimizing full-scale experiments in femtosecond spectroscopy is shown to
hold much promise.


title:
What is the true dropped calls rate when in the test it was found to be
  zero?

abstract:
  We study the distributions of dropped calls rates for different wireless
(cellular) carriers in different markets. Our statistics comprises over 700
different market/carrier combinations. We find that the dropped calls rates
distribution is very close to lognormal. We derive an equation for the most
probable dropped calls rate for particular carrier in particular market, which
depends on the number of dropped calls observed, total number of calls and the
parameters of the lognormal distribution. We apply this analysis to blocked and
"no service" calls as well.


title:
Deduction of Lorentz Transformation from the existence of absolute rest.
  Deduction of the speed of light in any frame of reference

abstract:
  We begin by admitting the following: (i) there is a frame of reference where
the speed of light is the same in any direction (that speed is c) (ii) the
average speed of light on a two-way journey is c in every frame of reference.
  From this two premises we obtain an expression for the speed of light which
implies the speed of light depends on the motion of the frame of reference.
Also from this two premises solely we deduct Lorentz Transformation.


title: Frictional coupling between sliding and spinning motion

abstract:
  We show that the friction force and torque, acting at a dry contact of two
objects moving and rotating relative to each other, are inherently coupled. As
a simple test system, a sliding and spinning disk on a horizontal flat surface
is considered. We calculate, and also measure, how the disk is slowing down,
and find that it always stops its sliding and spinning motion at the same
moment. We discuss the impact of this coupling between friction force and
torque on the physics of granular materials.


title: Pricing European Options in Realistic Markets

abstract:
  We investigate the relation between the fair price for European-style vanilla
options and the distribution of short-term returns on the underlying asset
ignoring transaction and other costs. We compute the risk-neutral probability
density conditional on the total variance of the asset's returns when the
option expires. If the asset's future price has finite expectation, the
option's fair value satisfies a parabolic partial differential equation of the
Black-Scholes type in which the variance of the asset's returns rather than a
trading time is the evolution parameter. By immunizing the portfolio against
large-scale price fluctuations of the asset, the valuation of options is
extended to the realistic case\cite{St99} of assets whose short-term returns
have finite variance but very large, or even infinite, higher moments. A
dynamic Delta-hedged portfolio that is statically insured against exceptionally
large fluctuations includes at least two different options on the asset. The
fair value of an option in this case is determined by a universal drift
function that is common to all options on the asset. This drift is interpreted
as the premium for an investment exposed to risk due to exceptionally large
variations of the asset's price. It affects the option valuation like an
effective cost-of-carry for the underlying in the Black-Scholes world would.
The derived pricing formula for options in realistic markets is arbitrage free
by construction. A simple model with constant drift qualitatively reproduces
the often observed volatility -skew and -term structure.


title:
A method for solving systems of non-linear differential equations with
  moving singularities

abstract:
  We present a method for solving a class of initial valued, coupled,
non-linear differential equations with `moving singularities' subject to some
subsidiary conditions. We show that this type of singularities can be
adequately treated by establishing certain `moving' jump conditions across
them. We show how a first integral of the differential equations, if available,
can also be used for checking the accuracy of the numerical solution.


title: Wavelength-Dependent Effects in Maxwell Optics

abstract:
  We present a new formalism for light beam optics starting with an exact
eight-dimensional matrix representation of the Maxwell equations. The
Foldy-Wouthuysen iterative diagonalization technique is employed to obtain a
Hamiltonian description for a system with varying refractive index. Besides,
reproducing all the traditional quasiparaxial terms, this method leads to
additional contributions, which are dependent on the wavelength, in the optical
Hamiltonian. This alternate prescription to obtain the aberration expansion is
applied to the axially symmetric graded index fiber. This results in the
wavelength-dependent modifications of the paraxial behaviour and the aberration
coefficients. Furthermore it predicts a wavelength-dependent image rotation. In
the low wavelength limit our formalism reproduces the Lie algebraic formalism
of optics. The Foldy-Wouthuysen technique employed by us is ideally suited for
the Lie algebraic approach to optics. The present study further strengthens the
close analogy between the various prescription of light and charged-particle
optics. All the associated machinery used in this formalism is described in the
text and the accompanying appendices.


title: Analogies between light optics and charged-particle optics

abstract:
  The close analogy between geometrical optics and the classical theories of
charged-particle beam optics have been known for a very long time. In recent
years, quantum theories of charged-particle beam optics have been presented
with the very expected feature of wavelength-dependent effects. With the
current development of non-traditional prescriptions of Helmholtz and Maxwell
optics respectively, accompanied with the wavelength-dependent effects, it is
seen that the analogy between the two systems persists. A brief account of the
various prescriptions and the parallel of the analogies is presented.


title: Experimental study of the Ca2 1S+1S asymptote

abstract:
  The filtered laser excitation technique was applied for measuring transition
frequencies of the Ca$_2$ B-X system from asymptotic levels of the
X$^1\Sigma_{\mathrm g}^{+}$ ground state reaching $v''=38$. That level has an
outer classical turning point of about 20~\AA which is only 0.2 \rcm below the
molecular $^1$S$+^1$S asymptote. Extensive analysis of the spectroscopic data,
involving Monte Carlo simulation, allowed for a purely experimental
determination of the long range parameters of the potential energy curve. The
possible values of the s-wave scattering length could be limited to be between
250$a_0$ and 1000$a_0$.


title: Modeling oscillatory Microtubule--Polymerization

abstract:
  Polymerization of microtubules is ubiquitous in biological cells and under
certain conditions it becomes oscillatory in time. Here simple reaction models
are analyzed that capture such oscillations as well as the length distribution
of microtubules. We assume reaction conditions that are stationary over many
oscillation periods, and it is a Hopf bifurcation that leads to a persistent
oscillatory microtubule polymerization in these models. Analytical expressions
are derived for the threshold of the bifurcation and the oscillation frequency
in terms of reaction rates as well as typical trends of their parameter
dependence are presented. Both, a catastrophe rate that depends on the density
of {\it guanosine triphosphate} (GTP) liganded tubulin dimers and a delay
reaction, such as the depolymerization of shrinking microtubules or the decay
of oligomers, support oscillations. For a tubulin dimer concentration below the
threshold oscillatory microtubule polymerization occurs transiently on the
route to a stationary state, as shown by numerical solutions of the model
equations. Close to threshold a so--called amplitude equation is derived and it
is shown that the bifurcation to microtubule oscillations is supercritical.


title: Notes on Quasi-Homogeneous Functions in Thermodynamics

abstract:
  A special kind of quasi-homogeneity occurring in thermodynamic potentials of
standard thermodynamics is pointed out. Some formal consequences are also
discussed.


title:
Co-Operative Phenomena as a Physical Paradigm for Special Relativity,
  Gravitation and Quantum Mechanics

abstract:
  We take Co-Operative Phenomena as a common physical conceptual base to
speculate on the existence of a medium and the properties that it must have to
physically understand some of the problems in Special Relativity, Gravitation
and Quantum Mechanics.


title: Toy models for the falling chimney

abstract:
  In this paper we review the theory of the ``falling chimney'', which deals
with the breaking in mid-air of tall structures, when they fall to the ground.
We show that these ruptures can be caused by either shear forces, typically
developing near the base, or by the bending of the structure, which is caused
primarily by the internal bending moment.
  In the latter case the breaking is more likely to occur between one third and
one half of the height of the chimney. Small scale toy models are used to
reproduce the dynamics of the falling chimney. By examining photos taken during
the fall of these models we test the adequacy of the outlined theory. This type
of experiment, easy to perform and conceptually challenging, can become part of
a rotational mechanics lab for undergraduate students.


title:
Ferromagnetic Antenna and its Application to Generation and Detection of
  Gravitational Radiation

abstract:
  A new type of antenna, which we have called Ferromagnetic Antenna, has been
considered for Generation and Detection of Gravitational Radiation. A simple
experiment, in which gravitational radiation at 10 GHz can be emitted and
received in laboratory, is presented.


title: Numerical methods for solving the time-dependent Maxwell equations

abstract:
  We review some recent developments in numerical algorithms to solve the
time-dependent Maxwell equations for systems with spatially varying
permittivity and permeability. We show that the Suzuki product-formula approach
can be used to construct a family of unconditionally stable algorithms, the
conventional Yee algorithm, and two new variants of the Yee algorithm that do
not require the use of the staggered-in-time grid. We also consider a one-step
algorithm, based on the Chebyshev polynomial expansion, and compare the
computational efficiency of the one-step, the Yee-type, the
alternating-direction-implicit, and the unconditionally stable algorithms. For
applications where the long-time behavior is of main interest, we find that the
one-step algorithm may be orders of magnitude more efficient than present
multiple time-step, finite-difference time-domain algorithms.


title: Atomic matter wave scanner

abstract:
  We report on the experimental realization of an atom optical device, that
allows scanning of an atomic beam. We used a time-modulated evanescent wave
field above a glass surface to diffract a continuous beam of metastable Neon
atoms at grazing incidence. The diffraction angles and efficiencies were
controlled by the frequency and form of modulation, respectively. With an
optimized shape, obtained from a numerical simulation, we were able to transfer
more than 50% of the atoms into the first order beam, which we were able to
move over a range of 8 mrad.


title: Notes on the Third Law of Thermodynamics.I

abstract:
  We analyze some aspects of the third law of thermodynamics. We first review
both the entropic version (N) and the unattainability version (U) and the
relation occurring between them. Then, we heuristically interpret (N) as a
continuity boundary condition for thermodynamics at the boundary T=0 of the
thermodynamic domain. On a rigorous mathematical footing, we discuss the third
law both in Carath\'eodory's approach and in Gibbs' one. Carath\'eodory's
approach is fundamental in order to understand the nature of the surface T=0.
In fact, in this approach, under suitable mathematical conditions, T=0 appears
as a leaf of the foliation of the thermodynamic manifold associated with the
non-singular integrable Pfaffian form $\delta Q_{rev}$. Being a leaf, it cannot
intersect any other leaf $S=$ const. of the foliation. We show that (N) is
equivalent to the requirement that T=0 is a leaf. In Gibbs' approach, the
peculiar nature of T=0 appears to be less evident because the existence of the
entropy is a postulate; nevertheless, it is still possible to conclude that the
lowest value of the entropy has to belong to the boundary of the convex set
where the function is defined.


title:
The Iterative Signature Algorithm for the analysis of large scale gene
  expression data

abstract:
  We present a new approach for the analysis of genome-wide expression data.
Our method is designed to overcome the limitations of traditional techniques,
when applied to large-scale data. Rather than alloting each gene to a single
cluster, we assign both genes and conditions to context-dependent and
potentially overlapping transcription modules. We provide a rigorous definition
of a transcription module as the object to be retrieved from the expression
data. An efficient algorithm, that searches for the modules encoded in the data
by iteratively refining sets of genes and conditions until they match this
definition, is established. Each iteration involves a linear map, induced by
the normalized expression matrix, followed by the application of a threshold
function. We argue that our method is in fact a generalization of Singular
Value Decomposition, which corresponds to the special case where no threshold
is applied. We show analytically that for noisy expression data our approach
leads to better classification due to the implementation of the threshold. This
result is confirmed by numerical analyses based on in-silico expression data.
We discuss briefly results obtained by applying our algorithm to expression
data from the yeast S. cerevisiae.


title:
Molecular Dynamics Simulation of Vibrational Phase Relaxation along the
  Critical Isochore of Nitrogen : The Role of Local Density Fluctuations

abstract:
  Vibrational dephasing of nitrogen molecule is known to show highly
interesting anomalies near its gas-liquid critical point. Here we present
theoretical and computational studies of the Raman linewidth of nitrogen along
the critical isochore. The linewidth is found to have a lambda shaped
temperature dependence near the critical point. As observed in experimental
studies, the calculated lineshape becomes Gaussian as the critical temperature
($T_{c}$) is approached. Both the present simulation and a mode coupling theory
(MCT) analysis show that the slow decay of the enhanced density fluctuations
near the critical point (CP), probed at the sub-picosecond time scales by
vibrational frequency modulation, along with an enhanced vibration-rotation
coupling, are the main causes of the observed anomalies.


title: Linking inverse square law with quantum mechanical probabilities

abstract:
  We use entropy to link fine-structure constant and cosmological constant. We
also link nuclear force and gravity. We step on the fundamentals of
consciousness for this new millennium with a scientific approach. Statistical
and quantum mechanical probabilistic approach to explain gravity has a
potential to extend physics to other branches of science. We meet the minds of
giants such as Newton, Einstein, and Gamow. Implicitly we show gravity as the
cumulative effect of all other forces, dominated by the strong force.


title: Electromagnetic focusing through a tilted dielectric interface

abstract:
  Focusing through a tilted dielectric interface is studied, and an explicit
expression for the electric field in the focal region is found. In the case of
small tilt angles, one obtains a focal shift, and only a simple aberration term
remains.


title:
Asymmetric emission of high energy electrons in the two-dimensional
  hydrodynamic expansion of large xenon clusters irradiated by intense laser
  fields

abstract:
  Energy spectra and angular distributions have been measured of electrons that
are emitted upon disassembly of $Xe_{150000}$ following irradiation by intense
(10$^{15}-10^{16}$ W cm$^{-2}$) laser pulses whose durations are varied over
the 100-2200 fs range. The cluster explosion dynamics occur in the hydrodynamic
regime. Electron emission is found to be unexpectedly asymmetric and exhibits a
resonance when the laser pulse duration is $\sim$1 ps. These results are
rationalized by extending the hydrodynamic model to also take into account the
force that the light field exerts on the polarization charge that is induced on
surface of the cluster. We show that the magnitude of this electrostrictive
force is comparable to those of Coulombic and the hydrodynamic forces, and it
exhibits resonance behavior. Contrary to earlier understanding, we find that
low-energy electrons are connected to the resonance in energy absorption by the
cluster. The high-energy electrons seem to be produced by a mechanism that is
not so strongly influenced by the resonance.


title:
Application of time-dependent density-functional theory to electron-ion
  couplng in ethylene

abstract:
  To examine the applicability of the time-dependent density-functional theory
(TDDFT) for treating the electron-nucleus coupling in excited states, we
calculate the strength distribution associated with the pi-pi* transition in
ethylene. The observed optical transition strength at 7-8.5 eV region shows a
complex structure arising from coupling to C-C stretch motion, to torsional
motion, and to Rydberg excitations. The mean energy of the observed peak is
reproduced to about 0.2 eV accuracy by the TDDFT in the local density
approximation (LDA). The reflection approximation is used to calculate the peak
broadening. Roughly half of the broadening can be attributed to the fluctuation
in the C-C coordinate. The asymmetry in the line shape is also qualitatively
reproduced by the C-C coordinate fluctuation. We find, in agreement with other
theoretical studies, that the torsional motion is responsible for the
progression of weak transition strength extending from the peak down to about 6
eV. The LDA reproduces the strength in this region to about factor of 3. We
conclude that the TDDFT is rather promising for calculating the electron
nucleus coupling at short times.


title: Self-assembly in the major ampullate gland of Nephila clavipes

abstract:
  We present a tentative interpretation of the origin of nematic liquid
crystalline order exhibited by dragline silk fibroin solutions collected from
the spider Nephila clavipes. Liquid crystallinity is thought to confer certain
rheological properties on the fibroin solution which are exploited during the
dragline spinning process. We show that the feasibility of liquid crystallinity
under physiological conditions depends critically on parameters characterising
the amino-acid sequence of the fibroin molecules.


title:
Preliminary results of an aging test of RPC chambers for the LHCb Muon
  System

abstract:
  The preliminary results of an aging test performed at the CERN Gamma
Irradiation Facility on a single--gap RPC prototype developed for the LHCb Muon
System are presented. The results are based on an accumulated charge density of
0.42 C/cm^2, corresponding to about 4 years of LHCb running at the highest
background rate. We observe a rise in the dark current and noise measured with
source off. The current drawn with source on steadily decreased, possibly
indicating an increase of resistivity of the chamber plates. The performance of
the chamber, studied with a muon beam under several photon flux values, is
found to still fulfill the LHCb operation requirements.


title:
An integrable localized approximation for interaction of two nearly
  anti-parallel sheets of the generalized vorticity in 2D ideal
  electron-magnetohydrodynamic flows

abstract:
  The formalism of frozen-in vortex lines for two-dimensional (2D) flows in
ideal incompressible electron magnetohydrodynamics (EMHD) is formulated. A
localized approximation for nonlinear dynamics of two close sheets of the
generalized vorticity is suggested and its integrability by the hodograph
method is demonstrated.


title:
The X-shaped, localized field generated by a Superluminal electric
  charge

abstract:
  It is now wellknown that Maxwell equations admit of wavelet-type solutions
endowed with arbitrary group-velocities (0 < v_g < infinity). Some of them,
which are rigidly moving and have been called localized solutions, attracted
large attention. In particular, much work has been done with regard to the
Superluminal localized solutions (SLS), the most interesting of which resulted
to be the "X-shaped" ones. The SLSs have been actually produced in a number of
experiments, always by suitable interference of ordinary-speed waves. In this
note we show, by contrast, that even a Superluminal charge creates an
electromagnetic X-shaped wave. Namely, on the basis of Maxwell equations, we
are able to evaluate the field associated with a Superluminal charge (under the
approximation of pointlikeness): and it results to constitute a very simple
example of true X-wave. [PACS nos.: 03.50.De; 03.30.+p; 41.20;Jb; 04.30.Db.
Keywords: Special relativity; Maxwell equations; Superluminal waves; X-shaped
waves; Localized beams; Wave propagation; Superluminal charges].


title:
Testing of the transionospheric radiochannel using data from the global
  GPS network

abstract:
  Using the international ground-based network of two-frequency receivers of
the GPS navigation system provides a means of carrying out a global, continuous
and fully-computerized monitoring of phase fluctuations of signals from
satellite-borne radio engineering systems caused by the Earth's inhomogeneous
and nonstationary ionosphere. We found that during major geomagnetic storms,
the errors of determination of the range, frequency Doppler shift and angles of
arrival of transionospheric radio signals exceeds the one for magnetically
quiet days by one order of magnitude as a minimum. This can be the cause of
performance degradation of current satellite radio engineering navigation,
communication and radar systems as well as of superlong-baseline radio
interferometry systems.


title:
Frequency range and explicit expressions for negative permittivity and
  permeability for an isotropic medium formed by a lattice of perfectly
  conducting $\Omega$ particles

abstract:
  An analytical model is presented for a rectangular lattice of isotropic
scatterers with electric and magnetic resonances. Each isotropic scatterer is
formed by putting appropriately 6 $\Omega$-shaped perfectly conducting
particles on the faces of a cubic unit cell. A self-consistent dispersion
equation is derived and then used to calculate correctly the effective
permittivity and permeability in the frequency band where the lattice can be
homogenized. The frequency range in which both the effective permittivity and
permeability are negative corresponds to the mini-band of backward waves within
the resonant band of the individual isotropic scatterer.


title: Pattern of Reaction Diffusion Front in Laminar Flows

abstract:
  Autocatalytic reaction between reacted and unreacted species may propagate as
solitary waves, namely at a constant front velocity and with a stationary
concentration profile, resulting from a balance between molecular diffusion and
chemical reaction. The effect of advective flow on the autocatalytic reaction
between iodate and arsenous acid in cylindrical tubes and Hele-Shaw cells is
analyzed experimentally and numerically using lattice BGK simulations. We do
observe the existence of solitary waves with concentration profiles exhibiting
a cusp and we delineate the eikonal and mixing regimes recently predicted.


title:
Nonlinear relationships between atmospheric aerosol and its gaseous
  precursors: Analysis of long-term air quality monitoring data by means of
  neural networks

abstract:
  The nonlinear features of the relationships between concentrations of aerosol
and volatile organic compounds (VOC) and oxides of nitrogen (NOx) in urban
environments are derived directly from data of long-term routine measurements
of NOx, VOC, and total suspended particulate matter (PM). The main idea of the
method used for the analysis is creation of special empirical models based on
artificial neural networks. These models which are in essence the nonlinear
extension of commonly used linear statistical models are believed to provide
the best fit for the real (nonlinear) PM-NOx-VOC relationships under different
atmospheric conditions. It is believed that such models may be useful in
context of various scientific and practical problems concerning atmospheric
aerosols. The method is demonstrated by the example of two empirical models
created with independent data-sets collected at two air quality monitoring
stations at South Coast Air Basin, California. It is shown that in spite of
considerable distance between the monitoring stations (more than 50 km) and
thus substantially different environmental conditions, the empirical models
manifest several common qualitative features. Specifically, it is found that,
under definite conditions, the decrease of the level of NOx or VOC may lead to
the increase of mass concentration of aerosol. It is argued that these features
are caused by the nonlinear dependence of hydroxyl radical on VOC and NOx.


title: Hexagonal dielectric resonators and microcrystal lasers

abstract:
  We study long-lived resonances (lowest-loss modes) in hexagonally shaped
dielectric resonators in order to gain insight into the physics of a class of
microcrystal lasers. Numerical results on resonance positions and lifetimes,
near-field intensity patterns, far-field emission patterns, and effects of
rounding of corners are presented. Most features are explained by a
semiclassical approximation based on pseudointegrable ray dynamics and boundary
waves. The semiclassical model is also relevant for other microlasers of
polygonal geometry.


title: Response to Compagno and Persico

abstract:
  Some mathematically incorrect claims of Compagno and Persico in their reply
(2002 J. Phys. A: Math. Gen. 35, 8965) to my comment on their recent paper on
self-dressing and radiation reaction in classical electrodynamics are pointed
out.


title: A Lattice Boltzmann method for simulations of liquid-vapor thermal flows

abstract:
  We present a novel lattice Boltzmann method that has a capability of
simulating thermodynamic multiphase flows. This approach is fully
thermodynamically consistent at the macroscopic level. Using this new method, a
liquid-vapor boiling process, including liquid-vapor formation and coalescence
together with a full coupling of temperature, is simulated for the first time.


title: Elementary thermodynamics of trapped particles

abstract:
  I develop simple thermodynamic relations for a collection of noninteracting
classical particles confined in a harmonic trap. The volume of such a trap is
not a good thermodynamic variable, so conventional expressions of the first law
of thermodynamics and the ideal gas law must be modified. I use the frequency
of oscillations about the minimum of the trap as an external parameter
characterizing the confinement, and derive elementary relations between
particle number, temperature, energy, oscillation frequency, and a generalized
pressure, that are analogous to conventional thermodynamic relations for an
ideal gas in a rigid volume. I also discuss heat capacities for trapped
particles.


title: Is Earthquake Triggering Driven by Small Earthquakes?

abstract:
  Using a catalog of seismicity for Southern California, we measure how the
number of triggered earthquakes increases with the earthquake magnitude. The
trade-off between this relation and the distribution of earthquake magnitudes
controls the relative role of small compared to large earthquakes. We show that
seismicity triggering is driven by the smallest earthquakes, which trigger
fewer events than larger earthquakes, but which are much more numerous. We
propose that the non-trivial scaling of the number of triggered earthquakes
emerges from the fractal spatial distribution of seismicity.


title: Non-Commutative Geometry, Spin and Quarks

abstract:
  In this paper we use considerations of non-commutative geometry to deduce a
model for QCD interactions. The model also explains within the same theoretical
framework hitherto purely phenomenological characteristics of the quarks like
their fractional charge, mass,handedness and confinement.


title: Physicists and the 1945 Decision to Drop the Bomb

abstract:
  In 1943 fear that the German war machine might use atomic bombs was abating
and among physicists another fear was taking its place - that of a postwar
nuclear arms race with worldwide proliferation of nuclear weapons. Manhattan
Project scientists and engineers began to discuss uses of nuclear energy in the
postwar world. Niels Bohr, Leo Szilard, James A. Franck and others launched a
concerted effort to lay groundwork for international control of the technology.
Realizing the devastation nuclear weapons could cause and that they could be
made and delivered much more cheaply than conventional weapons of the same
power, they tried to persuade policy makers to take into account long range
consequences of using atomic bombs and not base their decisions on short range
military expediency alone. They met with little success. The scientists' main
message, unheeded then and very relevant now, is that worldwide international
agreements are needed to provide for inspection and control of nuclear weapons
technology. Their memoranda and reports remain as historic documents eloquently
testifying to their concern.


title:
Low noise temperature control : application to an active cavity
  radiometer

abstract:
  We have designed low noise temperature sensing and control units with the
objective of using them for the fabrication of far infrared active cavity
radiometers. The sensing unit, first characterized at 300K using industrial
platinium resistance thermometers, has a noise level of
  25E-6 to 30E-6 Keff for a 3 hours measuring time and in a 1Hz bandwidth.
Using YBCO superconducting thermometers, the noise level goes down to 2.5E-6
Keff, which is strongly limited by excess 1/f noise in the YBCO film at the
superconducting transition. The sample holder used in the 90K experiments is
built with an auxiliary heating resistor, which enables an easy and accurate
identification of the electrothermal model, even in the closed loop operation.
Based on a design previously published by NIST, we estimate from these
experimental results that the overall noise limitations of radiometers could be
lowered by one order of magnitude.


title: Magneto-optical trap for metastable helium at 389 nm

abstract:
  We have constructed a magneto-optical trap (MOT) for metastable triplet
helium atoms utilizing the 2 3S1 -> 3 3P2 line at 389 nm as the trapping and
cooling transition. The far-red-detuned MOT (detuning Delta = -41 MHz)
typically contains few times 10^7 atoms at a relatively high (~10^9 cm^-3)
density, which is a consequence of the large momentum transfer per photon at
389 nm and a small two-body loss rate coefficient (2 * 10^-10 cm^3/s < beta <
1.0 * 10^-9 cm^3/s). The two-body loss rate is more than five times smaller
than in a MOT on the commonly used 2 3S1 -> 2 3P2 line at 1083 nm. Furthermore,
we measure a temperature of 0.46(1) mK, a factor 2.5 lower as compared to the
1083 nm case. Decreasing the detuning to Delta= -9 MHz results in a cloud
temperature as low as 0.25(1) mK, at small number of trapped atoms. The 389 nm
MOT exhibits small losses due to two-photon ionization, which have been
investigated as well.


title: Foam: A General purpose Monte Carlo Cellular Algorithm

abstract:
  A general-purpose, self-adapting Monte Carlo (MC) algorithm implemented in
the program {\tt Foam} is described. The high efficiency of the MC, that is
small maximum weight or variance of the MC weight is achieved by means of
dividing the integration domain into small cells. The cells can be
$n$-dimensional simplices, hyperrectangles or a Cartesian product of them. The
grid of cells, ``foam'', is produced in the process of the binary split of the
cells. The next cell to be divided and the position/direction of the division
hyperplane is chosen by the algorithm which optimizes the ratio of the maximum
weight to the average weight or (optionally) the total variance. The algorithm
is able to deal, in principle, with an arbitrary pattern of the singularities
in the distribution.


title:
Schrodinger equation with a spatially and temporally random potential:
  Effects of cross-phase modulation in optical communication

abstract:
  We model the effects of cross-phase modulation in frequency (or wavelength)
division multiplexed optical communications systems, using a Schr\"odinger
equation with a spatially and temporally random potential. Green's functions
for the propagation of light in this system are calculated using Feynman
path-integral and diagrammatic techniques. This propagation leads to a
non-Gaussian joint distribution of the input and output optical fields. We use
these results to determine the amplitude and timing jitter of a signal pulse
and to estimate the system capacity in analog communication.

categories: physics.optics cond-mat physics.data-an physics.gen-ph


title:
A two-state kinetic model for the unfolding of single molecules by
  mechanical force

abstract:
  We investigate the work dissipated during the irreversible unfolding of
single molecules by mechanical force, using the simplest model necessary to
represent experimental data. The model consists of two levels (folded and
unfolded states) separated by an intermediate barrier. We compute the
probability distribution for the dissipated work and give analytical
expressions for the average and variance of the distribution. To first order,
the amount of dissipated work is directly proportional to the rate of
application of force (the loading rate), and to the relaxation time of the
molecule. The model yields estimates for parameters that characterize the
unfolding kinetics under force in agreement with those obtained in recent
experimental results (Liphardt, J., et al. (2002) {\em Science}, {\bf 296}
1832-1835). We obtain a general equation for the minimum number of repeated
experiments needed to obtain an equilibrium free energy, to within $k_BT$, from
non-equilibrium experiments using the Jarzynski formula. The number of
irreversible experiments grows exponentially with the ratio of the average
dissipated work, $\bar{\Wdis}$, to $k_BT$.}


title:
Transit times of radiation through photonic bandgap materials: Pulse
  reshaping of classical and quantum fields in the time domain

abstract:
  We study the propagation of electromagnetic pulses through photonic bandgap
materials and relate time-domain pulse reshaping to observable transit times.
For layered dielectric mirrors we demonstrate how pulse reshaping of slowly
varying classical fields results in transit-time delays that are equivalent to
the group delay. The time-domain analysis emphasizes the causal origin of
negative group delays. We also study an analogous fully-quantized model and
show how the same time-domain analysis may be used to interpret observed delays
of single-photon fields.


title: Incorporation of New Information in an Approximate Hamiltonian

abstract:
  Additional information about the eigenvalues and eigenvectors of a physical
system demands extension of the effective Hamiltonian in use. In this work we
extend the effective Hamiltonian that describes partially a physical system so
that the new Hamiltonian comprises, in addition to the information in the old
Hamiltonian, new information, available by means of experiment or theory. A
simple expression of the enlarged Hamiltonian, which does not involve matrix
inversion, is obtained. It is also shown that the Lee-Suzuki transformation
effectively put the initial Hamiltonian in a diagonal block form.


title:
A dipole in a dielectric: Intriguing results and shape dependence of the
  distant electric field

abstract:
  The field of a point electric dipole in an infinite dielectric is obtained by
placing the dipole at the center of a spherical cavity of radius $R$ inside the
dielectric and then letting $R\to 0$. The result disagrees with the elementary
answer found in textbooks. The mathematical and physical reasons for the
disagreement are discussed. The discrepancy is confirmed by the same limiting
procedure applied to a uniformly polarized sphere embedded in the dielectric.
We next solve the same problem for a polarized spheroid immersed in an infinite
dielectric and find that the asymptotic potential shows an unexpected shape
dependence, even after taking the limit of an arbitrarily small spheroid. By
considering both oblate and prolate spheroids and taking appropriate limits, we
recover either the elementary textbook answer or the previous result found for
the polarized sphere.

categories: physics.class-ph cond-mat gr-qc hep-th physics.ed-ph


title:
XrdML, a new way to store (and exchange) X-ray powder diffraction
  measurement data

abstract:
  Recently PANalytical introduced the XrdML file format as a new data platform
for powder diffraction experiments. We will explain why an industrial standard
(XML) was chosen and show the XML schema used to precisely describe the
instrumental and experimental conditions. This schema is used to validate the
contents of the XrdML files. Additionally the integration of the XrdML files
with the MS Windows operating system and the MS Windows Explorer will be
demonstrated.


title:
Quantumlike Chaos in the Frequency Distributions of the Bases A, C, G, T
  in Drosophila DNA

abstract:
  Continuous periodogram power spectral analyses of fractal fluctuations of
frequency distributions of bases A, C, G, T in Drosophila DNA show that the
power spectra follow the universal inverse power-law form of the statistical
normal distribution. Inverse power-law form for power spectra of space-time
fluctuations is generic to dynamical systems in nature and is identified as
self-organized criticality. The author has developed a general systems theory,
which provides universal quantification for observed self-organized criticality
in terms of the statistical normal distribution. The long-range correlations
intrinsic to self-organized criticality in macro-scale dynamical systems are a
signature of quantumlike chaos. The fractal fluctuations self-organize to form
an overall logarithmic spiral trajectory with the quasiperiodic Penrose tiling
pattern for the internal structure. Power spectral analysis resolves such a
spiral trajectory as an eddy continuum with embedded dominant wavebands. The
dominant peak periodicities are functions of the golden mean. The observed
fractal frequency distributions of the Drosophila DNA base sequences exhibit
quasicrystalline structure with long-range spatial correlations or
self-organized criticality. Modification of the DNA base sequence structure at
any location may have significant noticeable effects on the function of the DNA
molecule as a whole. The presence of non-coding introns may not be redundant,
but serve to organize the effective functioning of the coding exons in the DNA
molecule as a complete unit.


title:
A new Manifestation of Atomic Parity Violation in Cesium: a Chiral
  Optical Gain induced by linearly polarized 6S-7S Excitation

abstract:
  We have detected, by using stimulated emission, an Atomic Parity Violation
(APV) in the form of a chiral optical gain of a cesium vapor on the 7S -
6P$_{3/2}$ transition,consecutive to linearly polarized 6S-7S excitation. We
demonstrate the validity of this detection method of APV, by presenting a 9%
accurate measurement of expected sign and magnitude. We underline several
advantages of this entirely new approach in which the cylindrical symmetry of
the set-up can be fully exploited. Future measurements at the percent level
will provide an important cross-check of an existing more precise result
obtained by a different method.


title: (p,q)-Sheaves and the Representability Problem

abstract:
  General properties of new models of the electronic Fock spaces based on the
notion of (p,q)-sheaves are studied. Interrelation between simple sheaves and
density operators is established. Explicit expressions for the transformed
reduced Hamiltonians in terms of the standard creation-annihilation operators
are presented. General scheme of parametrization of p-electron states by
k-electron means (k=2,3,...) is described and studied in detail for the case of
sheaves induced by k-electron wavefunctions. It is demonstrated that under
certain conditions p-electron problem may be reformulated as the eigenvalue
problem in k-electron space equipped with certain p-electron metric. Simple
numerical examples are given to illustrate our approach.


title:
A comparison of delayed radiobiological effects of depleted-uranium
  munitions versus fourth-generation nuclear weapons

abstract:
  It is shown that the radiological burden due to the battlefield use of circa
400 tons of depleted-uranium munitions in Iraq (and of about 40 tons in
Yugoslavia) is comparable to that arising from the hypothetical battle-field
use of more than 600 kt (respectively 60 kt) of high-explosive equivalent
pure-fusion fourth-generation nuclear weapons.
  Despite the limited knowledge openly available on existing and future nuclear
weapons, there is sufficient published information on their physical principles
and radiological effects to make such a comparison. In fact, it is shown that
this comparison can be made with very simple and convincing arguments so that
the main technical conclusions of the paper are undisputable -- although it
would be worthwhile to supplement the hand calculations presented in the paper
by more detailed computer simulations in order to consolidate the conclusions
and refute any possible objections.


title: NeXus Software Status

abstract:
  NeXus is a joint effort of both the synchrotron and neutron scattering
community to devlop a common data exchange format based on HDF. In order to
simplify access to NeXus-files a NeXus-API is provided. This NeXus-API has been
redesigned and expanded to cover both HDF versions 4 and 5. Only small changes
to the API were necessary in order to accomplish. A new NeXus-API for IDL based
on IDL C interface has been implemented.


title: Twist Defect in Chiral Photonic Structures

abstract:
  We demonstrate that twisting one part of a chiral photonic structure about
its helical axis produces a single circularly polarized localized mode that
gives rise to an anomalous crossover in propagation. Up to a crossover
thickness, this defect results in a peak in transmission and exponential
scaling of the linewidth for a circularly polarized wave with the same
handedness as structure. Above the crossover, however, the linewidth saturates
and the defect mode can be excited only by the oppositely polarized wave,
resulting in a peak in reflection instead of transmission.


title: Short Proof of Jacobi's Identity for Poisson Brackets

abstract:
  Making use of the theory of infinitesimal canonical transformations, a
concise proof is given of Jacobi's identity for Poisson brackets.

categories: physics.class-ph gr-qc hep-th physics.ed-ph


title: Developments for the IPNS Data Acquisition System Upgrade

abstract:
  The Intense Pulsed Neutron Source has been an operating user facility for
more than 20 years. Development of an upgrade for the data acquisition system
has been in progress for some time now. Now that the initial installation on
the test bed instrument (HRMECS) is completed new features and possibilities
are starting to come forward. Run setup is moving from large monolithic
programs to more flexible scripting. EPICS based controls allow flexible and
extendable instrument configurations. Hardware is also being made more
flexible. This flexibility allows implementation of new methods of binning
data, that better match instrument resolution. This allows better use of memory
and disk space. Increased flexibiliy has also allowed use of the new
time-of-flight modules in applications past their original intent.


title: Ultracold collision properties of metastable alkaline-earth atoms

abstract:
  Ultra-cold collisions of spin-polarized 24Mg,40Ca, and 88Sr in the metastable
3P2 excited state are investigated. We calculate the long-range interaction
potentials and estimate the scattering length and the collisional loss rate as
a function of magnetic field. The estimates are based on molecular potentials
between 3P2 alkaline-earth atoms obtained from ab initio atomic and molecular
structure calculations. The scattering lengths show resonance behavior due to
the appearance of a molecular bound state in a purely long-range interaction
potential and are positive for magnetic fields below 50 mT. A loss-rate model
shows that losses should be smallest near zero magnetic field and for fields
slightly larger than the resonance field, where the scattering length is also
positive.


title:
A Novel Scaled Boundary Finite Element Method in Computational
  Electromagnetics

abstract:
  A Novel Scaled boundary finite element method, initially developed in Civil
Engineering, is reformulated for solving boundary value problems in
computational electromagnetics.


title:
Divergence Condition for the novel Scaled Boundary Finite Element Method
  in Computational Electromagnetics

abstract:
  The divergence condition is reformulated in the scaled boundary coordinates
so as to prevent the spurious solutions in the finite element formulation.


title:
Application of the Covariant projection finite elements in the E field
  formulation for wave guide analysis

abstract:
  The use of covariant projection finite elements in the efficient 3-D vector
finite element analysis of wave guide is presented.


title:
On the short time prediction of earthquakes in the Balkan- Black Sea
  region based on geomagnetic field measurements and tide gravitational
  potential behavior

abstract:
  The paper is a first attempt for statistical estimation of method for a short
time prediction of incoming earthquake in the Balkan and Black Sea region from
January to June, 2002. The essence of the discovery is that the geomagnetic
local "quake" is a precursor of future earthquake, which time is determined by
the tide gravitational potential behavior. A Balkan Black Sea region
Earthquake's "When, where" Prediction Network is proposed.


title: Some Aspects of Modality in Analytical Mechanics

abstract:
  This paper discusses some of the modal involvements of analytical mechanics.
I first review the elementary aspects of the Lagrangian, Hamiltonian and
Hamilton-Jacobi approaches. I then discuss two modal involvements; both are
related to David Lewis' work on modality, especially on counterfactuals.
  The first is the way Hamilton-Jacobi theory uses ensembles, i.e. sets of
possible initial conditions. The structure of this set of ensembles remains to
be explored by philosophers.
  The second is the way the Lagrangian and Hamiltonian approaches' variational
principles state the law of motion by mentioning contralegal dynamical
evolutions. This threatens to contravene the principle that any actual truth,
in particular an actual law, is made true by actual facts. Though this threat
can be avoided, at least for simple mechanical systems, it repays scrutiny; not
least because it leads to some open questions.


title: Coordinated, Interactive Data Visualization for Neutron Scattering Data

abstract:
  The overall design of the Integrated Spectral Analysis Workbench (ISAW),
being developed at Argonne, provides for an extensible, highly interactive,
collaborating set of viewers for neutron scattering data. Large arbitrary
collections of spectra from multiple detectors can be viewed as an image, a
scrolled list of individual graphs, or using a 3D representation of the
instrument showing the detector positions. Data from an area detector can be
displayed using a contour or intensity map as well as an interactive table.
Selected spectra can be displayed in tables or on a conventional graph. A
unique characteristic of these viewers is their interactivity and coordination.
The position "pointed at" by the user in one viewer is sent to other viewers of
the same DataSet so they can track the position and display relevant
information. Specialized viewers for single crystal neutron diffractometers are
being developed. A "proof-of-concept" viewer that directly displays the 3D
reciprocal lattice from a complete series of runs on a single crystal
diffractometer has been implemented.


title: Exact phase shifts for atom interferometry

abstract:
  In the case of an external Hamiltonian at most quadratic in position and
momentum operators, we use the ABCD formulation of atom optics to establish an
exact analytical phase shift expression for atom interferometers with arbitrary
spatial or temporal beam splitter configurations. This result is expressed in
terms of coordinates and momenta of the wave packet centers at the interaction
vertices only.


title:
Analise dinamica da tendencia para o equilibrio num modelo simples: a
  Segunda Lei de Newton e a Segunda Lei da Termodinamica

abstract:
  We relate Newton's Second Law with the Second Law of Thermodynamics through
the analysis of a simple model introducing a dynamic pressure concept. From
this analyses we can clarify some conceptual problems resulting from several
concepts of heat and work on the First Law of Thermodynamics.


title: CARPS: An integrated proposal and data collection system

abstract:
  Modern scripting languages and database tools combined provide a new
framework for developing beam-line control and data management software. The
CARPS system supports data collection by storing low level beam-line control
commands in a database and playing these commands back to collect data sets.
This system is combined with proposal and data management tools for support of
both local and remote users.


title: Transient polarization dynamics in a CO$_2$ laser

abstract:
  We study experimentally and theoretically the polarization alternation during
the switch-on transient of a quasi-isotropic CO$_2$ laser emitting on the
fundamental mode. The observed transient dynamics is well reproduced by means
of a model which provides a quantitative discrimination between the intrinsic
asymmetry due to the kinetic coupling of molecules with different angular
momenta, and the extrinsic anisotropies, due to a tilted intracavity window.
Furthermore, the experiment provides a numerical assignment for the decay rate
of the coherence term for a CO$_2$ laser.


title:
Increasing Market Penetration of LED Traffic Signals in New York State:
  Review of Articles and Information on LED Traffic Signals

abstract:
  A primary purpose of this review is to identify and summarize recently
published information about the use and performance of light-emitting diode
(LED) traffic signals. It consists of two sections: a synopsis of experiences
of municipalities using LED traffic signals in 1999 and 2000, and a discussion
of technical, economic and market issues surrounding the deployment of LED
signals. This review includes articles and reports published in 1999 and 2000.


title: Science In Trauma

abstract:
  Quantum theory has been proved as an outstanding mystery in modern science.
The predictions of science have turned out to be probabilistic. The principle
of determinism has failed. For systems like weather, earthquakes, rolling dices
etc... and of course human behavior it has proved impossible, for science, to
describe a state of the system accurately for a long time into the future.
Moreover, modern cosmology has to rely on philosophical assumptions. It is
argued -- by taking into account of the views of learned scientists and
philosophers -- that modern science can never explain everything and it is a
hard fact to discover the ``Theory Of Everything''. On the other hand, modern
scientific technology have damaged our environment and posed serious threats
for the future development of science. All these facts and results put a big
question-mark (?) on the grass-root level working of science. In fact, all
scientific researches are based upon ordinary sense perception, which keeps the
outer physical universe as a separate entity, that is something quite
independent of the observer. Basically, it is the observer -- the knower --
which makes perception possible. Astonishingly, the knower -- human mind -- is
not included in our scientific theories. One should not forget human-being
(human mind) is a part of nature and an essential component of our
observations, so it's inclusion in scientific theories is must in order to
recover modern science from the drastic state of trauma.


title: A Critical Approach to Total and Partial Derivatives

abstract:
  In this brief note we critically examine the process of partial and of total
differentiation, showing some of the problems that arise when we relate both
concepts. A way to solve all the problems is proposed.


title:
On the distance dependence of electron transfer through molecular
  bridges and wires

abstract:
  The dependence of electron transfer rates and yields in bridged molecular
systems on the bridge length, and the dependence of the zero-bias conduction of
molecular wires on wire length are discussed. Both phenomena are controlled by
tunneling across the molecular bridge and are consequently expected to show
exponential decrease with bridge length that is indeed often observed.
Deviations from this exponential dependence for long bridges, in particular a
crossover to a very weak dependence on bridge length were recently observed
experimentally and discussed theoretically in terms of thermal relaxation and
dephasing on the bridge. Here we discuss two other factors that potentially
affect the bridge length dependence of these phenomena. First, in experiments
initiated by an initial preparation of a non-stationary "donor" state the
initial energy is not well defined. A small contribution from initially
populated eigenstates that are of mostly bridge-level character may dominate
transmission for long bridges, resulting in weak or no bridge-length
dependence. Secondly, in steady state experiments the distribution of initial
states (for example the Fermi distribution at the electrodes in conduction
experiments) will cause deviations from exponential dependence on wire length
because even a small population in higher energy states will dominate the
transmission through long wires. For the first scenario we show that the
crossover behavior observed for electron transfer in DNA between G and GGG
species separated by AT chains can be largely reproduced just by initial state
effects.


title: On the possibility of supercavitation in the quantum ether

abstract:
  In this speculative note some of the conceivable options of supercavitation
in the vacuum of quantized field theory are discussed. The resulting modes of
propagation could in principle be faster than the velocity of light in
unbounded space-time.


title:
Listening to the coefficient of restitution and the gravitational
  acceleration of a bouncing ball

abstract:
  We show that a well known method for measuring the coefficient of restitution
of a bouncing ball can also be used to obtain the gravitational acceleration.


title: A model of memory, learning and recognition

abstract:
  We propose a simple model of recognition, short-term memory, long-term memory
and learning.


title: Analytical Expressions for Parrondo Games

abstract:
  We present some new analytical expressions for the so-called Parrondo effect,
where simple coin-flipping games with negative expected value are combined into
a winning game. Parrondo games are state-dependent. By identifying the game
state variable, we can compute the stationary game state probabilities. Mixing
losing games increases the probability of entering into a game state with
positive value, as can be seen clearly from our analytical expressions for the
Parrondo game value.


title: Global warming: What does the data tell us?

abstract:
  We analyze global surface temperature data obtained at 13472 weather stations
from the year 1702 to 1990. The mean annual temperature of a station fluctuates
from year to year by typically +-0.6oC (one standard deviation). Superimposed
on this fluctuation is a linear increase of the temperature by typically 0.40oC
per century ever since reliable data is available, i.e. since 1702. The world
population has doubled from 1952 to 1990, yet we see no statistically
significant acceleration of global warming in this period. We conclude that the
effect of humankind on global warming up to 1990 is 0.0 +- 0.1oC.


title: A Segunda Lei da Termodinamica na formulacao da Lei de Hooke

abstract:
  Hooke's Law is analyzed taking the Second Law of Thermodynamics into
consideration. It is shown that the energy of a spring isn't always 1/2 k xx -
this value is actually the energy of the spring plus the energy of the
atmosphere that surrounds it. On a quasi-isentropic aproximation in which the
dynamic force is approximately the same as the static force, k is not a
constant. Only by considering an ideal spring where k is constant and only on a
static regime, can we say the energy is 1/2 k xx. For any dynamic regime of
such an ideal spring, the energy of the spring is a function of its temperature
and therefore is different from 1/2 k xx. If any given mass is moving attached
to an ideal spring, the movement will eventually cease even if such movement
occurs in vacuum. The dynamic force is not the static force kx. The Second Law
of Thermodynamics is essential in order to formulate Hooke's Law.


title:
An investigation into a half page from Newton's Principia in the wake of
  Chandra

abstract:
  There is a section in Chandrashekar's ''Newton's Principia for the Common
Reader '', (Clarendon Press, Oxford, 1995) in which he claims to find a small
error in the Principia. . However we believe that there is a mistake of
interpretation underlying Chandra's claim and that the Principia is correct as
it stands. This short paper describes Chandra's misinterpretation of a
geometric construction of Newton and gives an outline of Newton's demonstration
by following the standard English version of the Principia line by line and
converting it into modern mathematical notation in the spirit of Chandra's
book.


title:
Temperature measurement at the end of a cantilever using oxygen
  paramagnetism in solid air

abstract:
  We demonstrate temperature measurement of a sample attached to the end of a
cantilever using cantilever magnetometry of solid air ``contamination'' of the
sample surface. In experiments like our Magnetic Resonance Force Microscopy
(MRFM), the sample is mounted at the end of a thin cantilever with small
thermal conductance. Thus, the sample can be at a significantly different
temperature than the bulk of the instrument. Using cantilever magnetometry of
the oxygen paramagnetism in solid air provides the temperature of the sample,
without any modifications to our MRFM (Magnetic Resonance Force Microscopy)
apparatus.


title:
170 Nanometer Nuclear Magnetic Resonance Imaging using Magnetic
  Resonance Force Microscopy

abstract:
  We demonstrate one-dimensional nuclear magnetic resonance imaging of the
semiconductor GaAs with 170 nanometer slice separation and resolve two regions
of reduced nuclear spin polarization density separated by only 500 nanometers.
This is achieved by force detection of the magnetic resonance, Magnetic
Resonance Force Microscopy (MRFM), in combination with optical pumping to
increase the nuclear spin polarization. Optical pumping of the GaAs creates
spin polarization up to 12 times larger than the thermal nuclear spin
polarization at 5 K and 4 T. The experiment is sensitive to sample volumes
containing $\sim 4 \times 10^{11}$ $^{71}$Ga$/\sqrt{Hz}$. These results
demonstrate the ability of force-detected magnetic resonance to apply magnetic
resonance imaging to semiconductor devices and other nanostructures.


title:
Retarded Electromagnetic Interaction and Dynamic Foundation of Classical
  Statistical Mechanics and Elimination of Reversibility Paradox of Time
  reversal

abstract:
  It is proved in the paper that the non-conservative dissipative force and
asymmetry of time reversal can be naturally introduced into classical
statistical mechanics after retarded electromagnetic interaction between
charged microparticles is considered. In this way, the rational dynamic
foundation for classical statistical physics can established and the revised
Liouville equation is obtained. The micro-canonical ensemble, the canonical
ensemble, the distribution of near-independent subsystem, the distribution law
of the Maxwell- Boltzmann and the Maxwell distribution of velocities are
achieved directly from the Liouville equation without using the hypothesis of
equal probability. The micro-canonical ensemble is considered unsuitable as the
foundation of equivalent state theory again, for most of equivalent states of
isolated systems are not the states with equal probabilities actually. The
reversibility paradoxes in the processes of non-equivalent evolutions of
macro-systems can be eliminated completely, and the united description of
statistical mechanics of equivalent and nonequivalent states is reached. The
revised BBKGY series equations and hydromechanics equations are reduced, the
non-equivalent entropy of general systems is defined and the principle of
entropy increment of the non-equivalent entropy is proved at last.


title:
Characteristic lengths at moving contact lines for a perfectly wetting
  fluid: the influence of speed on the dynamic contact angle

abstract:
  It is common to relate the dynamic contact angle $\theta_d$ to the relative
speed between the substrate and the contact line; theory suggests $\theta_d^3
\propto U$. In fact, available physical models show that the dynamic angle
involves speed logarithmically and in a model dependent manner. Experimental
data consistent with this interpretation is cited.


title: Low Temperature Performance of a Large Area Avalanche Photodiode

abstract:
  A Large Area Avalanche Photodiode (LAAPD) was studied, aiming to access its
performance as light detector at low temperatures, down to -80 C. The excess
noise factor, F, was measured and found to be approximately independent of the
temperature. A linear dependence of F on the APD gain with a slope of 0.00239
+/- 0.00008 was observed for gains above 100. The detection of low intensity
light pulses, producing only a few primary electron-hole pairs in the
photodiode, is reported.


title:
Energies, transition rates, and electron electric dipole moment
  enhancement factors for Ce IV and Pr V

abstract:
  Energies, transition rates, and electron electric dipole moment (EDM)
enhancement factors are calculated for low-lying states of Ce IV and Pr V using
relativistic many-body perturbation theory. This study is related to recent
investigations of the more complicated Gd IV ion, which is promising for
electron EDM experiments. The ions Ce IV and Pr V both have a single valence
electron, permitting one to carry out reliable ab-initio calculations of energy
levels, transition rates and other atomic properties using well developed
computational methods.