title:
Theory of optical imaging beyond the diffraction limit with a far-field
  superlens

abstract:
  Recent theoretical and experimental studies have shown that imaging with
resolution well beyond the diffraction limit can be obtained with so-called
superlenses. Images formed by such superlenses are, however, in the near field
only, or a fraction of wavelength away from the lens. In this paper, we propose
a far-field superlens (FSL) device which is composed of a planar superlens with
periodical corrugation. We show in theory that when an object is placed in
close proximity of such a FSL, a unique image can be formed in far-field. As an
example, we demonstrate numerically that images of 40 nm lines with a 30 nm gap
can be obtained from far-field data with properly designed FSL working at 376nm
wavelength.


title: Mixing in manipulated turbulence

abstract:
  A new computational framework for the simulation of turbulent flow through
complex objects and along irregular boundaries is presented. This is motivated
by the application of metal foams in compact heat-transfer devices, or as
catalyst substrates in process-engineering. The flow-consequences of such
complicated objects are incorporated by adding explicit multiscale forcing to
the Navier-Stokes equations. The forcing represents the simultaneous agitation
of a wide spectrum of length-scales when flow passes through the complex
object. It is found that a considerable modulation of the traditional energy
cascading can be introduced with a specific forcing strategy. In spectral
space, forcing yields strongly localized deviations from the common Kolmogorov
scaling law, directly associated with the explicitly forced scales. In
addition, the accumulated effect of forcing induces a significant non-local
alteration of the kinetic energy including the spectrum for the large scales.
Consequently, a manipulation of turbulent flow can be achieved over an extended
range, well beyond the directly forced scales. The turbulent mixing of a
passive scalar field is also investigated, in order to quantify the
physical-space modifications of transport processes in multiscale forced
turbulence. The surface-area and wrinkling of level-sets of the scalar field
are monitored as measures of the influence of explicit forcing on the local and
global mixing efficiency.


title: Rotational modes of oscillation of rodlike dust grains in a plasma

abstract:
  Three dimensional rotatory modes of oscillations in a one-dimensional chain
of rodlike charged particles or dust grains in a plasma are investigated. The
dispersion characteristics of the modes are analyzed. The stability of
different equilibrium orientations of the rods, phase transitions between the
different equilibria, and a critical dependence on the relative strength of the
confining potential are analyzed. The relations of these processes with liquid
crystals, nanotubing, and plasma coating are discussed.


title: How many independent bets are there?

abstract:
  The benefits of portfolio diversification is a central tenet implicit to
modern financial theory and practice. Linked to diversification is the notion
of breadth. Breadth is correctly thought of as the number of in- dependent bets
available to an investor. Conventionally applications us- ing breadth
frequently assume only the number of separate bets. There may be a large
discrepancy between these two interpretations. We uti- lize a simple
singular-value decomposition (SVD) and the Keiser-Gutman stopping criterion to
select the integer-valued effective dimensionality of the correlation matrix of
returns. In an emerging market such as South African we document an estimated
breadth that is considerably lower than anticipated. This lack of
diversification may be because of market concentration, exposure to the global
commodity cycle and local currency volatility. We discuss some practical
extensions to a more statistically correct interpretation of market breadth,
and its theoretical implications for both global and domestic investors.

categories: physics.soc-ph physics.data-an q-fin.PM q-fin.ST


title: The high energy frontier and the collaboration in collider experiments

abstract:
  In this note I shall review the Japan-Italy cooperative work in high energy
collider experiments, in particular OPAL at LEP, CDF at Fermilab, ZEUS at HERA
and ATLAS at the future LHC.


title: On the Mutual Coefficient of Restitution in Two Car Collinear Collisions

abstract:
  In the paper two car collinear collisions are discussed using Newton's law of
mechanics, conservation of energy and linear constitutive law connecting impact
force and crush. Two ways of calculating the mutual restitution coefficient are
given: one based on car masses and one based on car stiffness. A numerical
example of an actual test is provided.


title:
New interpretation of the atomic spectra and other quantum phenomena: A
  mixed mechanism of classical $LC$ circuits and quantum wave-particle duality

abstract:
  We study the energy conversion laws of the macroscopic harmonic $LC $
oscillator, the electromagnetic wave (photon) and the hydrogen atom. As our
analysis indicates that the energies of these apparently different systems obey
exactly the same energy conversion law. Based on our results and the
wave-particle duality of electron, we find that the atom in fact is a natural
microscopic $LC$ oscillator. In the framework of classical electromagnetic
field theory we analytically obtain, for the hydrogen atom, the quantized
electron orbit radius. Without the adaptation of any other fundamental
principles of quantum mechanics, we present a reasonable explanation of the
polarization of photon, the Zeeman effect, Selection rules and Pauli exclusion
principle. Particularly, it is found that a pairing Pauli electron can move
closely and steadily in a DNA-like double helical electron orbit. Our results
also reveal an essential connection between electron spin and the intrinsic
helical movement of electron and indicate that the spin itself is the effect of
quantum confinement. In addition, a possible physical mechanism of
superconductivity and the deeper physical understandings of the electron mass,
zero point energy, and the hardness property of electron are also provided.
Finally, we show analytically that the Dirac's quantization of magnetic
monopole is merely a special handed electron at absolute zero-temperature,
which strongly suggests that any efforts to seek for the magneticmonopole in
real space will be entirely in vain. Furthermore, it appears that the
electron's spin and the magnetic monopole are actually two different concepts
for one possible physical phenomenon.


title: Generalization of the Schott energy in electrodynamic radiation theory

abstract:
  We discuss the origin of the Schott energy in the Abraham-Lorentz version of
electrodynamic radiation theory and how it can be used to explain some apparent
paradoxes. We also derive the generalization of this quantity for the
Ford-O'Connell equation, which has the merit of being derived exactly from a
microscopic Hamiltonian for an electron with structure and has been shown to be
free of the problems associated with the Abraham-Lorentz theory. We emphasize
that the instantaneous power supplied by the applied force not only gives rise
to radiation (acceleration fields), but it can change the kinetic energy of the
electron and change the Schott energy of the velocity fields. The important
role played by boundary conditions is noted.


title: Scale-free avalanche dynamics in the stock market

abstract:
  Self-organized criticality has been claimed to play an important role in many
natural and social systems. In the present work we empirically investigate the
relevance of this theory to stock-market dynamics. Avalanches in stock-market
indices are identified using a multi-scale wavelet-filtering analysis designed
to remove Gaussian noise from the index. Here new methods are developed to
identify the optimal filtering parameters which maximize the noise removal. The
filtered time series is reconstructed and compared with the original time
series. A statistical analysis of both high-frequency Nasdaq E-mini Futures and
daily Dow Jones data is performed. The results of this new analysis confirm
earlier results revealing a robust power law behaviour in the probability
distribution function of the sizes, duration and laminar times between
avalanches. This power law behavior holds the potential to be established as a
stylized fact of stock market indices in general. While the memory process,
implied by the power law distribution of the laminar times, is not consistent
with classical models for self-organized criticality, we note that a power-law
distribution of the laminar times cannot be used to rule out self-organized
critical behaviour.


title: The Effects of Geometry on the Hyperpolarizability

abstract:
  Extensive studies in the past have focused on precise calculations of the
nonlinear-optical susceptibility of thousands of molecules. In this work, we
use the broader approach of considering how geometry and symmetry alone play a
role. We investigate the nonlinear optical response of potential energy
functions that are given by a superposition of force centers (representing the
nuclear charges) that lie in various planar geometrical arrangements. We find
that for certain specific geometries, such as an octupolar-like molecule with
donors and acceptors of varying strengths at the branches, the
hyperpolarizability is near the {\em fundamental limit}. In these cases, the
molecule is observed to be well approximated by a three-level model -
consistent with the three-level ansatz previously used to calculate the {\em
fundamental limits}. However, when the hyperpolarizability is below the {\em
apparent limit} (about a factor of thirty below the {\em fundamental limit})
the system is no longer representable by a three-level model; where both
two-level and a many-state models are found to be appropriate, depending on the
symmetry.


title: Efficiency of Carnot Cycle with Arbitrary Gas Equation of State

abstract:
  The derivation of the efficiency of Carnot cycle is usually done by
calculating the heats involved in two isothermal processes and making use of
the associated adiabatic relation for a given working substance's equation of
state, usually the ideal gas. We present a derivation of Carnot efficiency
using the same procedure with Redlich-Kwong gas as working substance to answer
the calculation difficulties raised by Agrawal and Menon. We also show that
using the same procedure, the Carnot efficiency may be derived regardless of
the functional form of the gas equation of state.


title:
Long-term Memory and Volatility Clustering in Daily and High-frequency
  Price Changes

abstract:
  We study the long-term memory in diverse stock market indices and foreign
exchange rates using the Detrended Fluctuation Analysis(DFA). For all daily and
high-frequency market data studied, no significant long-term memory property is
detected in the return series, while a strong long-term memory property is
found in the volatility time series. The possible causes of the long-term
memory property are investigated using the return data filtered by the AR(1)
model, reflecting the short-term memory property, and the GARCH(1,1) model,
reflecting the volatility clustering property, respectively. Notably, we found
that the memory effect in the AR(1) filtered return and volatility time series
remains unchanged, while the long-term memory property either disappeared or
diminished significantly in the volatility series of the GARCH(1,1) filtered
data. We also found that in the high-frequency data the long-term memory
property may be generated by the volatility clustering as well as higher
autocorrelation. Our results imply that the long-term memory property of the
volatility time series can be attributed to the volatility clustering observed
in the financial time series.


title: On the effect of dispersion on nonlinear phase noise

abstract:
  The variance of nonlinear phase noise is analyzed by including the effect of
intrachannel cross-phase modulation (IXPM)-induced nonlinear phase noise.
Consistent with Ho and Wang [1] but in contrary to the conclusion of both Kumar
[2] and Green et al. [3], the variance of nonlinear phase noise does not
decrease much with the increase of chromatic dispersion. The results are
consistent with a careful reexamination of both Kumar [2] and Green et al. [3].


title: A study of the personal income distribution in Australia

abstract:
  We analyze the data on personal income distribution from the Australian
Bureau of Statistics. We compare fits of the data to the exponential,
log-normal, and gamma distributions. The exponential function gives a good
(albeit not perfect) description of 98% of the population in the lower part of
the distribution. The log-normal and gamma functions do not improve the fit
significantly, despite having more parameters, and mimic the exponential
function. We find that the probability density at zero income is not zero,
which contradicts the log-normal and gamma distributions, but is consistent
with the exponential one. The high-resolution histogram of the probability
density shows a very sharp and narrow peak at low incomes, which we interpret
as the result of a government policy on income redistribution.


title: Mapping the Sensitive Volume of an Ion-Counting Nanodosimeter

abstract:
  We present two methods of independently mapping the dimensions of the
sensitive volume in an ion-counting nanodosimeter. The first method is based on
a calculational approach simulating the extraction of ions from the sensitive
volume, and the second method on probing the sensitive volume with 250 MeV
protons. Sensitive-volume maps obtained with both methods are compared and
systematic errors inherent in both methods are quantified.


title:
Additional information for the paper `Entropy of seismic electric
  signals: Analysis in natural time under time-reversal'

abstract:
  After the submission of the paper, three strong earthquakes with magnitude
around 6.0-units occurred on October 17 and October 20, 2005, with epicenters
in the Aegean Sea, at a distance {\em only} 100km from MYT station at which the
intense signals $M_1$ to $M_4$ -analyzed in the main text- have been recorded.
This confirms experimentally the proposed criterion we used for the
classification of these signals as Seismic Electric Signals (SES). Moreover, we
show that, if we follow the procedure described in [P.A. Varotsos, N. V.
Sarlis, H. K. Tanaka and E. S. Skordas {\it Phys. Rev. E} {\bf 72}, 041103
(2005)], the analysis in the natural time of the seismicity after the SES
initiation allows the estimation of the time window of the impending
earthquakes with very good accuracy.


title: Observer with a constant proper acceleration

abstract:
  Relying on the equivalence principle, a first approach of the general theory
of relativity is presented using the spacetime metric of an observer with a
constant proper acceleration. Within this non inertial frame, the equation of
motion of a freely moving object is studied and the equation of motion of a
second accelerated observer with the same proper acceleration is examined. A
comparison of the metric of the accelerated observer with the metric due to a
gravitational field is also performed.


title:
Spectral line shape modeling and ion temperature fluctuations in tokamak
  edge plasmas

abstract:
  In this work, we use a passive advection model for ion temperature
fluctuations, in order to investigate their effects on Doppler Spectral line
shapes. The relevance of the model is discussed in the framework of the
Braginskii equations, and the subsequent Probability Density Function
evaluation relies on results obtained in neutral fluids. The resulting Doppler
line profiles are shown to exhibit characteristic exponential tails.


title:
Initiating a Mexican wave: An instantaneous collective decision with
  both short and long range interactions

abstract:
  An interesting example for collective decision making is the so-called
Mexican wave during which the spectators in a stadium leap to their feet with
their arms up and then sit down again following those to their left (right)
with a small delay. Here we use a simple, but realistic model to explain how
the combination of the local and global interactions of the spectators produces
a breaking of the symmetry resulting in the replacement of the symmetric
solution -- containing two propagating waves -- by a single wave moving in one
of the two possible directions. Our model is based on and compared to the
extensive observations of volunteers filling out the related questionnaire we
have posted on the Internet. We find that, as a function of the parameter
controlling the strength of the global interactions, the transition to the
single wave solution has features reminiscent of discontinuous transitions.
After the spontaneous symmetry breaking the two directions of propagation are
still statistically equivalent. We investigate also how this remaining symmetry
is broken in real stadia by a small asymmetrical term in the perception of
spectators.


title:
Raman observations of quantum interference in the $\nu_1 / 2\nu_2$ Fermi
  dyad region of carbon dioxide

abstract:
  Coherent anti-Stokes Raman spectra (CARS) were obtained for CO$_2$ in a
positive column discharge. The intensities of the Raman transitions to the
$\nu_1 / 2\nu_2$ Fermi dyad decrease significantly when the discharge is turned
on because of equalization of the lower and upper state populations by electron
impact excitation, in a manner similar to saturation. The strength of the 1285
cm$^{-1}$ transition is observed to decrease by a factor of 20 greater than the
1388 cm$^{-1}$ line due to a quantum interference decreasing the vibrational
relaxation rate of the upper state of the 1285 cm$^{-1}$ transition. This
interference is verified by measurements of the decay rates from the state.
Experiments ruling out Stark effects and polarization effects are described.
Supporting the observed rapid vibrational excitation by electrons, a strong hot
band transition $20^00 \leftarrow 02^20$ at 1425.61 cm$^{-1}$ was observed.
These observations are compared with recent measurements of the Raman spectra
of CO$_2$ heated in a flame.


title:
Nonlinear traveling waves as a framework for understanding turbulent
  drag reduction

abstract:
  Nonlinear traveling waves that are precursors to laminar-turbulent transition
and capture the main structures of the turbulent buffer layer have recently
been found to exist in all the canonical parallel flow geometries. We study the
effect of polymer additives on these "exact coherent states" (ECS), in the
plane Poiseuille geometry. Many key aspects of the turbulent drag reduction
phenomenon are found, including: delay in transition to turbulence; drag
reduction onset threshold; diameter and concentration effects. Furthermore,
examination of the ECS existence region leads to a distinct prediction,
consistent with experiments, regarding the nature of the maximum drag reduction
regime. Specifically, at sufficiently high wall shear rates, viscoelasticity is
found to completely suppress the normal (i.e. streamwise-vortex-dominated)
dynamics of the near wall region, indicating that the maximum drag reduction
regime is dominated by a distinct class of flow structures.


title: Controlled Irradiative Formation of Penitentes

abstract:
  Spike-shaped structures are produced by light-driven ablation in very
different contexts. Penitentes 1-4 m high are common on Andean glaciers, where
their formation changes glacier dynamics and hydrology. Laser ablation can
produce cones 10-100 microns high with a variety of proposed applications in
materials science. We report the first laboratory generation of
centimeter-scale snow and ice penitentes. Systematically varying conditions
allows identification of the essential parameters controlling the formation of
ablation structures. We demonstrate that penitente initiation and coarsening
requires cold temperatures, so that ablation leads to sublimation rather than
melting. Once penitentes have formed, further growth of height can occur by
melting. The penitentes intially appear as small structures (3 mm high) and
grow by coarsening to 1-5 cm high. Our results are an important step towards
understanding and controlling ablation morphologies.


title: DNA entropic elasticity for short molecules attached to beads

abstract:
  Single-molecule experiments in which force is applied to DNA or RNA molecules
have enabled important discoveries of nucleic acid properties and nucleic
acid-enzyme interactions. These experiments rely on a model of the polymer
force-extension behavior to calibrate the experiments; typically the
experiments use the worm-like chain (WLC) theory for double-stranded DNA and
RNA. This theory agrees well with experiments for long molecules. Recent
single-molecule experiments have used shorter molecules, with contour lengths
in the range of 1-10 persistence lengths. Most WLC theory calculations to date
have assumed infinite molecule lengths, and do not agree well with experiments
on shorter chains. Key physical effects that become important when shorter
molecules are used include (i) boundary conditions which constrain the allowed
fluctuations at the ends of the molecule and (ii) rotational fluctuations of
the bead to which the polymer is attached, which change the apparent extension
of the molecule. We describe the finite worm-like chain (FWLC) theory, which
takes into account these effects. We show the FWLC predictions diverge from the
classic WLC solution for molecules with contour lengths a few times the
persistence length. Thus the FWLC will allow more accurate experimental
calibration for relatively short molecules, facilitating future discoveries in
single-molecule force microscopy.


title:
Comment on "Test of constancy of speed of light with rotating cryogenic
  optical resonators"

abstract:
  A recent experiment by Antonini et. al. [Phys. Rev. A {\bf 71}, 050101R
2005], set new limits on Lorentz violating parameters in the frame-work of the
photon sector of the Standard Model Extension (SME),
$\tilde{\kappa}_{e-}^{ZZ}$, and the Robertson-Mansouri-Sexl (RMS) framework,
$\beta-\delta-1/2$. The experiment had significant systematic effects caused by
the rotation of the apparatus which were only partly analysed and taken into
account. We show that this is insufficient to put a bound on
$\tilde{\kappa}_{e-}^{ZZ}$ and the bound on $\beta-\delta-1/2$ represents a
five-fold improvement not a ten-fold improvement as claimed.
  (For reply see Phys. Rev. A 72, 066102 (2005) DOI:
10.1103/PhysRevA.72.066102)


title:
Is the assumption of a special system of reference consistent with
  Special Relativity? Definitely yes, special approaches show it!

abstract:
  We compare the results obtained by interpreting some fundamental relativistic
experiments from the point of view of two alternative theories: Einstein's
special relativity theory and the Lorentz-Poincare theory admitting the
existence of a special reference frame relative to which we can measure
absolute velocities. The experiments that we consider here are the time
dilation, the radar echo, the Doppler Effect and the radar detection. The most
important result is that both theories lead to the Lorentz-Einstein
transformations for the space-time coordinates of the same event. This
conclusion enables us to assert that the anisotropy in the light propagation
fades away in the case of these particular experiments


title: Giant bubble pinch-off

abstract:
  Self-similarity has been the paradigmatic picture for the pinch-off of a
drop. Here we will show through high-speed imaging and boundary integral
simulations that the inverse problem, the pinch-off of an air bubble in water,
is not self-similar in a strict sense: A disk is quickly pulled through a water
surface, leading to a giant, cylindrical void which after collapse creates an
upward and a downward jet. Only in the limiting case of large Froude number the
neck radius $h$ scales as $h(-\log h)^{1/4} \propto \tau^{1/2}$, the purely
inertial scaling. For any finite Froude number the collapse is slower, and a
second length-scale, the curvature of the void, comes into play. Both
length-scales are found to exhibit power-law scaling in time, but with
different exponents depending on the Froude number, signaling the
non-universality of the bubble pinch-off.


title: Sector analysis for a FTSE portfolio of stocks

abstract:
  Using a portfolio of stocks from the London Stock Exchange FTSE100 index
(FTSE), we study both the time dependence of their correlations and the
normalized tree length of the associated minimal spanning tree (MST). The first
four moments of the distribution of correlations and lengths of the tree are
examined in detail and differences in behaviour noted. For different economic
groups and industries, clustering is evident. However comparing the
classification used prior to 2006 with that introduced in January 2006 it is
clear that the new classification, apart from one or two notable exceptions, is
much more compatible with the clustering obtained by the MST analysis. We
finally compare the MST for real data with that obtained for a synthetic {\it
random market}. The latter tree would seem more like the structure found by
Coronnello {\it et al.} for trees based on high frequency data.


title: Validation of Lasing in Active Nanocavities

abstract:
  An unambiguous proof of lasing in an active nanocavity with ultrahigh
spontaneous emission coupling factor (beta = 0.65) is presented. To distinguish
the subtle lasing threshold features from possible material-related phenomena,
such as saturable absorption in the gain medium, a series of active
nanocavities with different values of beta have been designed to systematically
approach the high-beta device. The demonstration of the lasing threshold is
obtained through the observation of the transition from thermal to coherent
light photon statistics that is well understood and identified in the beta << 1
lasing regime. The systematic investigation allows a more definitive validation
of the onset of lasing in these active nanocavities.


title: Nonequilibrium Thermodynamics of Wealth Condensation

abstract:
  We analyze wealth condensation for a wide class of stochastic economy models
on the basis of the economic analog of thermodynamic potentials, termed
transfer potentials. The economy model is based on three common transfers modes
of wealth: random transfer, profit proportional to wealth and motivation of
poor agents to work harder. The economies never reach steady state. Wealth
condensation is the result of stochastic tunneling through a metastable
transfer potential. In accordance with reality, both wealth and income
distribution transiently show Pareto tails for high income subjects. For
metastable transfer potentials, exponential wealth condensation is a robust
feature. For example with 10 % annual profit 1% of the population owns 50 % of
the wealth after 50 years. The time to reach such a strong wealth condensation
is a hyperbolic function of the annual profit rate.


title: Re-inventing Willis

abstract:
  Scientists often re-invent things that were long known. Here we review these
activities as related to the mechanism of producing power law distributions,
originally proposed in 1922 by Yule to explain experimental data on the sizes
of biological genera, collected by Willis. We also review the history of
re-invention of closely related branching processes, random graphs and
coagulation models.

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


title: Parametric instabilities in magnetized multicomponent plasmas

abstract:
  This paper investigates the excitation of various natural modes in a
magnetized bi-ion or dusty plasma. The excitation is provided by parametrically
pumping the magnetic field. Here two ion-like species are allowed to be fully
mobile. This generalizes our previous work where the second heavy species was
taken to be stationary. Their collection of charge from the background neutral
plasma modifies the dispersion properties of the pump and excited waves. The
introduction of an extra mobile species adds extra modes to both these types of
waves. We firstly investigate the pump wave in detail, in the case where the
background magnetic field is perpendicular to the direction of propagation of
the pump wave. Then we derive the dispersion equation relating the pump to the
excited wave for modes propagating parallel to the background magnetic field.
It is found that there are a total of twelve resonant interactions allowed,
whose various growth rates are calculated and discussed.


title: Can physics laws be derived from monogenic functions?

abstract:
  This is a paper about geometry and how one can derive several fundamental
laws of physics from a simple postulate of geometrical nature. The method uses
monogenic functions analysed in the algebra of 5-dimensional spacetime,
exploring the 4-dimensional waves that they generate. With this method one is
able to arrive at equations of relativistic dynamics, quantum mechanics and
electromagnetism. Fields as disparate as cosmology and particle physics will be
influenced by this approach in a way that the paper only suggests. The paper
provides an introduction to a formalism which shows prospects of one day
leading to a theory of everything and suggests several areas of future
development.


title:
Molecular librations in a liquid investigated by ultrafast optical Kerr
  effect spectroscopy

abstract:
  We propose a detail theoretical approach modeling molecular librations in
liquid investigated by ultrafast optically heterodyne detected optical Kerr
effect (OHD-OKE). The approach has been applied for fluoroform molecular liquid
and new information about spectrum, relaxation time and time domain librations
has been obtained.


title:
A Tabulation and Critical Analysis of the Wavelength-Dependent
  Dielectric Image Coefficient for the Interaction Exerted by a Surface onto a
  Neighbouring Excited Atom

abstract:
  The near-field interaction of an atom with a dielectric surface is inversely
proportional to the cube to the distance to the surface, and its coupling
strength depends on a dielectric image coefficient. This coefficient, simply
given in a pure electrostatic approach by (eps-1) / (eps+1) with eps the
permittivity, is specific to the frequency of each of the various relevant
atomic transition : it depends in a complex manner from the bulk material
properties, and can exhibit resonances connected to the surface polariton
modes. We list here the surface resonances for about a hundred of optical
windows whose bulk properties are currently tabulated. The study concentrates
on the infrared domain because it is the most relevant for atom-surface
interaction. Aside from this tabulation, we discuss simple hints to estimate
the position of surface resonances, and how uncertainties in the bulk data for
the material dramatically affect the predictions for the image coefficient. We
also evaluate the contribution of UV resonances of the material to the non
resonant part of the image coefficient.


title: Geomagnetic storm dependence on the solar flare class

abstract:
  Content. Solar flares are often used as precursors of geomagnetic storms. In
particular, Howard and Tappin (2005) recently published in A&A a dependence
between X-ray class of solar flares and Ap and Dst indexes of geomagnetic
storms which contradicts to early published results.
  Aims. We compare published results on flare-storm dependences and discuss
possible sources of the discrepancy.
  Methods. We analyze following sources of difference: (1) different intervals
of observations, (2) different statistics and (3) different methods of event
identification and comparison.
  Results. Our analysis shows that magnitude of geomagnetic storms is likely to
be independent on X-ray class of solar flares.


title:
Anisotropy, inhomogeneity and inertial range scalings in turbulent
  convection

abstract:
  This paper provides a detailed study of scale-by-scale budgets in turbulent
Rayleigh-B\'enard convection and aims at testing the applicability of
Kolmogorov (1941) and Bolgiano (1959) theories for this flow. Particular
emphasis is laid on anisotropic and inhomogeneous effects: the SO(3)
decomposition of structure functions (Arad et al 1999) and a method of
description of inhomogeneities proposed by Danaila et al (2001) are used to
derive inhomogeneous and anisotropic generalizations of Kolmogorov and Yaglom
equations applying to RB convection. The various terms in these equations are
computed using data from a DNS of turbulent Boussinesq convection at
$\rayleigh=10^6$ and $\prandtl=1$ with aspect ratio A=5. The analysis of the
isotropic component demonstrates that the shape of the third-order velocity
structure function is significantly influenced by buoyancy forcing and
large-scale inhomogeneities, while the mixed third-order structure function
appearing in Yaglom equation exhibits a clear scaling exponent 1 in a small
range of scales. The magnitudes of the various low $\ell$ degree anisotropic
components of the equations are also estimated and are shown to be comparable
to their isotropic counterparts at moderate to large scales. Finally, a
qualitative analysis shows that the influence of buoyancy forcing at scales
smaller than the Bolgiano scale is likely to remain important up to
$\rayleigh=10^9$, thus preventing Kolmogorov scalings from showing up in
convective flows at lower Rayleigh numbers.


title: Classical Field Theory of Cerenkov Radiation Devices

abstract:
  The usually continuous and incoherent Cerenkov radiation (CR) is converted
into coherent and narrow-band radiation from within a dielectric-line cavity
excited by a dc electron beam. We have studied the self-oscillating behavior of
a device that operates at $\sim22$ GHz by calculating explicitly the electron
self-bunching and radiation growing processes. The nonlinear gain of the device
and the radiation spectrum are also calculated. The agreement to the
experiments indicates that the developed formalism could be used in designing a
THz source based on cavity Cerenkov radiation.


title:
A global simulation for laser driven MeV electrons in $50\mu m$-diameter
  fast ignition targets

abstract:
  The results from 2.5-dimensional Particle-in-Cell simulations for the
interaction of a picosecond-long ignition laser pulse with a plasma pellet of
50-$\mu m$ diameter and 40 critical density are presented. The high density
pellet is surrounded by an underdense corona and is isolated by a vacuum region
from the simulation box boundary. The laser pulse is shown to filament and
create density channels on the laser-plasma interface. The density channels
increase the laser absorption efficiency and help generate an energetic
electron distribution with a large angular spread. The combined distribution of
the forward-going energetic electrons and the induced return electrons is
marginally unstable to the current filament instability. The ions play an
important role in neutralizing the space charges induced by the the temperature
disparity between different electron groups. No global coalescing of the
current filaments resulted from the instability is observed, consistent with
the observed large angular spread of the energetic electrons.


title: Geometry of the divergences problem in QFT

abstract:
  The divergences problem in QFT should be overcame presumably due to the
unification of the fundamental interactions. We evidently cannot to achieve
this goal now. Together with this there are divergences in problems where the
high-energy processes simply cannot be involved (say electron self-energy,
Lamb's shift, etc.). Last ones reflect the formal character of perturbation
theory applied to interacting secondly quantized amplitudes of the pointwise
particles. These difficulties are borrowed partly from the classical theory. I
would like to establish some general framework for the future unified theory
avoiding to use the method of classical analogy.


title: A laser-driven target of high-density nuclear polarized hydrogen gas

abstract:
  We report the best figure-of-merit achieved for an internal nuclear polarized
hydrogen gas target and a Monte Carlo simulation of spin-exchange optical
pumping. The dimensions of the apparatus were optimized using the simulation
and the experimental results were in good agreement with the simulation. The
best result achieved for this target was 50.5% polarization with 58.2% degree
of dissociation of the sample beam exiting the storage cell at a hydrogen flow
rate of $1.1\times 10^{18}$ atoms/s.


title: Optimal Traffic Networks

abstract:
  Inspired by studies on the airports' network and the physical Internet, we
propose a general model of weighted networks via an optimization principle. The
topology of the optimal network turns out to be a spanning tree that minimizes
a combination of topological and metric quantities. It is characterized by a
strongly heterogeneous traffic, non-trivial correlations between distance and
traffic and a broadly distributed centrality. A clear spatial hierarchical
organization, with local hubs distributing traffic in smaller regions, emerges
as a result of the optimization. Varying the parameters of the cost function,
different classes of trees are recovered, including in particular the minimum
spanning tree and the shortest path tree. These results suggest that a
variational approach represents an alternative and possibly very meaningful
path to the study of the structure of complex weighted networks.


title: Studies for a Photon Collider at the ILC

abstract:
  One option at the International Linear Collider is to convert the electron
beams into high energy photon beams by Compton scattering a few millimetres in
front of the interaction region. Selected physics channels for this option have
been analysed and technical issues have been studied. So far no showstoppers
for this option have been found.


title: Level Crossing Analysis of the Stock Markets

abstract:
  We investigate the average frequency of positive slope $\nu_{\alpha}^{+}$,
crossing for the returns of market prices.
  The method is based on stochastic processes which no scaling feature is
explicitly required. Using this method we define new quantity to quantify stage
of development and activity of stocks exchange. We compare the Tehran and
western stock markets and show that some stocks such as Tehran (TEPIX) and New
Zealand (NZX) stocks exchange are emerge, and also TEPIX is a non-active market
and financially motivated to absorb capital.


title:
The Effect of Gas Ion Bombardment on the Secondary Electron Yield of
  TiN, TiCN and TiZrV Coatings For Suppressing Collective Electron Effects in
  Storage Rings

abstract:
  In many accelerator storage rings running positively charged beams,
ionization of residual gas and secondary electron emission (SEE) in the beam
pipe will give rise to an electron cloud which can cause beam blow-up or loss
of the circulating beam. A preventative measure that suppresses electron cloud
formation is to ensure that the vacuum wall has a low secondary emission yield
(SEY). The SEY of thin films of TiN, sputter deposited Non-Evaporable Getters
and a novel TiCN alloy were measured under a variety of conditions, including
the effect of re-contamination from residual gas.


title:
Classical Interpretation to Relatively Stable Physical Statistical
  Distributions

abstract:
  Very recently we present a theory to discuss the nature of light and show
that the quantization of light energy in vacuum can be derived directly from
classical electromagnetic theory. In the theory a key concept of stability of
statistical distribution and a variational procedure searching for those of
relatively stable statistical distributions were introduced. This is a
classical interpretation to the concept and method concerned. It would be
helpful for avoiding some of possible obsession from the variational procedure
and its final quantum result.


title:
Failure of energy stability in Oldroyd-B fluids at arbitrarily low
  Reynolds numbers

abstract:
  Energy theory for incompressible Newtonian fluids is, in many cases, capable
of producing strong absolute stability criteria for steady flows. In those
fluids the kinetic energy naturally defines a norm in which perturbations decay
monotonically in time at sufficiently low (but non-zero) Reynolds numbers.
There are, however, at least two obstructions to the generalization of such
methods to Oldroyd-B fluids. One previously recognized problem is the fact that
the natural energy does not correspond to a proper functional norm on
perturbations. Another problem, original to this work, is the fact that
fluctuations in Oldroyd-B fluids may be subject to non-normal amplification at
arbitrarily low Reynolds numbers (albeit at sufficiently large Weissenberg
numbers). Such transient growth, occuring even when the base flow is linearly
stable, precludes the uniform monotonic decay of any reasonable measure of the
disturbance's amplitude.


title: Vibrational spectrum of the H5+ molecule using quantum Monte Carlo

abstract:
  In this article we present a caracterization of the vibrational spectrum of
the H5+ molecule using the correlation function quantum Monte Carlo (CFQMC)
method and a genetic algorithm study of the topology of the potential energy
surface used in this work. The vibrational modes associated with the H3+ - H2
torsion and stretching posses very flat minima. As a consequence the
fundamental frequencies corresponding to these modes are poorly described in
the harmonic approximation. The vibrational frequencies obtained in this work
are in good agreement with the available experimental data as well as other
computational methods found in literature. In our genetic algorithm study of
the potential energy surface using cartesian coordinates we have found some
unexpected minima. A careful analysis shows that some of these minima are
described by the same curviliniar coordinates in which the potential is
described. However, they represent nonequivalent molecular geometries.


title:
Manufacture of and Apparatus for Nearly Frictionless Operation of a
  Rotatable Array of Micro-Mirrors in a Solar Concentrator Sheet

abstract:
  Due to an ever growing shortage of conventional energy sources, there is an
increasingly intense interest in harnessing solar energy. The instant invention
can contribute to the goal of achieving environmentally clean solar energy to
be competitive with conventional energy sources. A novel method is described
for manufacturing a transparent sheet with an embedded array of mirrored
spheroidal micro-balls for use in a solar energy concentrator, and analogous
applications such as optical switches and solar rocket assist. The micro-balls
are covered with a thin spherical shell of lubricating liquid so that they are
free to rotate in an almost frictionless encapsulation in the sheet. Novel
method and apparatus are presented for producing the preferred embodiment of a
close-packed monolayer of the array of mirrored micro-balls.


title: MovieMaker: A Parallel Movie-Making Software for Large Scale Simulations

abstract:
  We have developed a parallel rendering software for scientific visualization
of large-scale, three-dimensional, time development simulations. The goal of
this software, MovieMaker, is to generate a movie, or a series of visualization
images from totally one TB-scale data within one night (or less than 12 hours).
The isocontouring, volume rendering, and streamlines are implemented.
MovieMaker is a parallel program for the shared memory architecture with
dynamic load balancing and overlapped disk I/O.


title: Bremsstrahlung vs. Thomson scattering in VUV-FEL plasma experiments

abstract:
  We determine the spectral photon yield from a hot dense plasma irradiated by
VUV-FEL light in a Thomson scattering experiment. The Thomson signal is
compared to the emission background mainly caused by bremsstrahlung photons. We
determine experimental conditions that allow for a signal-to-background ratio
larger than unity. By derivation of the Thomson and the bremsstrahlung spectrum
from linear response theory we present a consistent quantum statistical
approach to both processes. This allows for a systematic treatment of medium
and quantum effects such as dynamical screening and strong collisions. Results
are presented for the threshold FEL-intensity as a function of density and
temperature. We show that the account for quantum effects leads to larger
thresholds as compared to previous work.


title: Ground state wave function and energy of the lithium atom

abstract:
  Highly accurate nonrelativistic ground-state wave function and energy of the
lithium atom is obtained in the Hylleraas basis set. The leading relativistic
corrections,as represented by Breit-Pauli Hamiltonian, are obtained in fair
agreement with the former results. The calculational method is based on the
analytical evaluation of Hylleraas integrals with the help of recursion
relations.


title: Observable Effects of Noncommutative Spacetime on the Hydrogen Atom

abstract:
  We present a brief historical introduction to the motivations behind quantum
mechanics and quantum field theory on noncommutative spacetime and provide an
insightful technique, readily accessible to the undergraduate student, to
examine the measurable effects of noncommutative spacetime on the familiar
hydrogen atom. Finally, we compare our results to those derived from more
sophisticated approaches.


title: Real time Quantum state holography using coherent transients

abstract:
  In a two level atom, real-time quantum state holography is performed through
interferences between quantum states created by a reference pulse and a chirped
pulse resulting in coherent transients. A sequence of several measurements
allows one to measure the real and imaginary parts of the excited state wave
function. These measurements are performed during the interaction with the
ultrashort laser pulse. The extreme sensitivity of this method to the pulse
shape provides a tool for electric field measurement.


title:
Multiscale dynamics of biological cells with chemotactic interactions:
  from a discrete stochastic model to a continuous description

abstract:
  The Cellular Potts Model (CPM) has been used for simulating various
biological phenomena such as differential adhesion, fruiting body formation of
the slime mold Dictyostelium discoideum, angiogenesis, cancer invasion,
chondrogenesis in embryonic vertebrate limbs, and many others. In this paper,
we derive continuous limit of discrete one dimensional CPM with the chemotactic
interactions between cells in the form of a Fokker-Planck equation for the
evolution of the cell probability density function. This equation is then
reduced to the classical macroscopic Keller-Segel model. In particular, all
coefficients of the Keller-Segel model are obtained from parameters of the CPM.
Theoretical results are verified numerically by comparing Monte Carlo
simulations for the CPM with numerics for the Keller-Segel model.


title:
A "partitioned leaping" approach for multiscale modeling of chemical
  reaction dynamics

abstract:
  We present a novel multiscale simulation approach for modeling stochasticity
in chemical reaction networks. The approach seamlessly integrates
exact-stochastic and "leaping" methodologies into a single "partitioned
leaping" algorithmic framework. The technique correctly accounts for stochastic
noise at significantly reduced computational cost, requires the definition of
only three model-independent parameters and is particularly well-suited for
simulating systems containing widely disparate species populations. We present
the theoretical foundations of partitioned leaping, discuss various options for
its practical implementation and demonstrate the utility of the method via
illustrative examples.


title:
A Theory of Quantum Gravity may not be possible because Quantum
  Mechanics violates the Equivalence Principle

abstract:
  Quantum mechanics clearly violates the weak equivalence principle (WEP). This
implies that quantum mechanics also violates the strong equivalence principle
(SEP), as shown in this paper. Therefore a theory of quantum gravity may not be
possible unless it is not based upon the equivalence principle, or if quantum
mechanics can change its mass dependence. Neither of these possibilities seem
likely at the present time. Examination of QM in n-space, as well as
relativistic QM equations does not change this conclusion.


title:
Wavelet Bicoherence Analysis as a Method for Investigating Coherent
  Structures in an Electron Beam with an Overcritical Current

abstract:
  Results are presented from numerical modeling of the effect of the
inhomogeneity of the ion background on the complicated spatiotemporal dynamics
of an electron beam with a virtual cathode in plane geometry. The possibility
is demonstrated of increasing the generation frequency without changing the
beam current. The spatiotemporal structures that form in the beam and govern
the complicated stochastic dynamics of the nonuniform electron-plasma system
under consideration are investigated by the methods of wavelet bicoherence and
by analyzing the calculated electron trajectories on the space-time diagrams

categories: physics.plasm-ph nlin.CD physics.comp-ph physics.data-an


title: Darwin-Vlasov Simulations of magnetized Plasmas

abstract:
  We present a new Vlasov code for collisionless plasmas in the nonrelativistic
regime. A Darwin approximation is used for suppressing electromagnetic vacuum
modes. The spatial integration is based on an extension of the
flux-conservative scheme, introduced by Filbet et al. [J. Comp. Phys. Vol. 172
(2001) 166]. Performance and accuracy is demonstrated by comparing it to a
standard finite differences scheme for two test cases, including a Harris sheet
magnetic reconnection scenario. This comparison suggests that the presented
scheme is a promising alternative to finite difference schemes.


title:
Critique on the measurement of neutron cross-sections by the Deep
  Inelastic Neutron Scattering technique

abstract:
  We analyze a recent work of Mayers and Abdul-Redah,[J.Phys.: Condens. Matter
{\bf 16}, 4811 (2004)] in which the autors report the existence of anomalous
neutron cross sections in several systems. In the present work we show that the
Deep Inelastic Neutron Scattering (DINS) results presented by the authors are
affected by an inaccurate formalism employed for obtaining nuclear momentum
distributions, and therefore definitive conclusions cannot be drawn on the
subject of anomalous cross sections. We also show the reasons why the exact
formalism for obtaining momentum distributions that we recently published must
be employed for analysing the experimental data instead of the approximations
performed in the mentioned work. We also point out serious inconsistencies
between different results reported in the mentioned work, as well as
incompatibilities with previous results published by the authors. These
inconsistencies, as well as experimental evidence against the existence of
anomalous cross sections not considered by the authors, reinforce the need to
revise critically the procedures on which the usual DINS data analysis is based
as well as the proper characterisation of the experimental set-up.


title: A nonextensive approach to the dynamics of financial observables

abstract:
  We present results about financial market observables, specifically returns
and traded volumes. They are obtained within the current nonextensive
statistical mechanical framework based on the entropy
$S_{q}=k\frac{1-\sum\limits_{i=1}^{W} p_{i} ^{q}}{1-q} (q\in \Re)$ ($S_{1}
\equiv S_{BG}=-k\sum\limits_{i=1}^{W}p_{i} \ln p_{i}$). More precisely, we
present stochastic dynamical mechanisms which mimic probability density
functions empirically observed. These mechanisms provide possible
interpretations for the emergence of the entropic indices $q$ in the time
evolution of the corresponding observables. In addition to this, through
multi-fractal analysis of return time series, we verify that the dual relation
$q_{stat}+q_{sens}=2$ is numerically satisfied, $q_{stat}$ and $q_{sens}$ being
associated to the probability density function and to the sensitivity to
initial conditions respectively. This type of simple relation, whose
understanding remains ellusive, has been empirically verified in various other
systems.


title:
Structure and evolution of online social relationships: Heterogeneity in
  warm discussions

abstract:
  With the advancement in the information age, people are using electronic
media more frequently for communications, and social relationships are also
increasingly resorting to online channels. While extensive studies on
traditional social networks have been carried out, little has been done on
online social network. Here we analyze the structure and evolution of online
social relationships by examining the temporal records of a bulletin board
system (BBS) in a university. The BBS dataset comprises of 1,908 boards, in
which a total of 7,446 students participate. An edge is assigned to each
dialogue between two students, and it is defined as the appearance of the name
of a student in the from- and to-field in each message. This yields a weighted
network between the communicating students with an unambiguous group
association of individuals. In contrast to a typical community network, where
intracommunities (intercommunities) are strongly (weakly) tied, the BBS network
contains hub members who participate in many boards simultaneously but are
strongly tied, that is, they have a large degree and betweenness centrality and
provide communication channels between communities. On the other hand,
intracommunities are rather homogeneously and weakly connected. Such a
structure, which has never been empirically characterized in the past, might
provide a new perspective on social opinion formation in this digital era.


title:
Dynamics of polydisperse irreversible adsorption: a pharmacological
  example

abstract:
  Many drug delivery systems suffer from undesirable interactions with the host
immune system. It has been experimentally established that covalent attachment
(irreversible adsorption) of suitable macromolecules to the surface of the drug
carrier can reduce such undesirable interactions. A fundamental understanding
of the adsorption process is still lacking. In this paper, the classical random
irreversible adsorption model is generalized to capture certain essential
processes involved in pharmacological applications, allowing for macromolecules
of different sizes, partial overlapping of the tails of macromolecules, and the
influence of reactions with the solvent on the adsorption process. Working in
one dimension, an integro-differential evolution equation for the adsorption
process is derived and the asymptotic behaviour of the surface area covered and
the number of molecules attached to the surface is studied. Finally,
equation-free dynamic renormalization tools are applied to study the
asymptotically self-similar behaviour of the adsorption statistics.


title:
Radiation of Relativistic Particles for Quasiperiodic Motion in a
  Transparent Medium

abstract:
  The radiation of relativistic charged particles for the quasiperiodic motion
in a transparent medium is considered. For motion of the general kind the
differential probability of the process is obtained. For planar motion the
spectral intensity of radiation is found. The different cases of radiation in
the medium-filled undulators are studied. In particular, the influence of
Cherenkov radiation on the undulator one is discussed.


title:
Emergent Behavior in Agent Networks: Self-Organization in Wasp and Open
  Source Communities

abstract:
  Understanding the complex dynamics of communities of software developers
requires a view of such organizations as a network of interacting agents
involving both goals and constraints. Beyond their special features, these
systems display some overall patterns of organization not far from the ones
seen in other types of organizations, including both natural and artificial
entities. By looking at both software developers and social insects as agents
interacting in a complex network, we found common statistical patterns of
organization. Here, simple self-organizing processes leading to the formation
of hierarchies in wasp colonies and open source communities are studied. Our
analysis further validates simple models of formation of wasp hierarchies based
on individual learning. In the open source community, a few members are clearly
distinguished from the rest of the community with different reinforcement
mechanisms.


title: A Parallel Mesh-Adaptive Framework for Hyperbolic Conservation Laws

abstract:
  We report on the development of a computational framework for the parallel,
mesh-adaptive solution of systems of hyperbolic conservation laws like the
time-dependent Euler equations in compressible gas dynamics or
Magneto-Hydrodynamics (MHD) and similar models in plasma physics. Local mesh
refinement is realized by the recursive bisection of grid blocks along each
spatial dimension, implemented numerical schemes include standard
finite-differences as well as shock-capturing central schemes, both in
connection with Runge-Kutta type integrators. Parallel execution is achieved
through a configurable hybrid of POSIX-multi-threading and MPI-distribution
with dynamic load balancing. One- two- and three-dimensional test computations
for the Euler equations have been carried out and show good parallel scaling
behavior. The Racoon framework is currently used to study the formation of
singularities in plasmas and fluids.


title:
Evolving Social Weighted Networks: Nonlocal Dynamics of Open Source
  Communities

abstract:
  Complex networks emerge under different conditions through simple rules of
growth and evolution. Such rules are typically local when dealing with
biological systems and most social webs. An important deviation from such
scenario is provided by communities of agents engaged in technology
development, such as open source (OS) communities. Here we analyze their
network structure, showing that it defines a complex weighted network with
scaling laws at different levels, as measured by looking at e-mail exchanges.
We also present a simple model of network growth involving non-local rules
based on betweenness centrality. The model outcomes fit very well the observed
scaling laws, suggesting that the overall goals of the community and the
underlying hierarchical organization play a key role is shaping its dynamics.


title: Solar arcades as possible minimum dissipative relaxed states

abstract:
  In our work, we have proposed the arcade structures as minimum dissipative
relaxed states (including both the viscous and resistive channels) pertaining
to a two-fluid description of the plasma. The obtained relaxed state is non
force-free in nature and appropriate to an open system with external drives.
The Euler-Lagrange equations are solved in Cartesian coordinates subject to the
existing photospheric boundary conditions. The solutions are seen to support
flow-containing arcade like magnetic field configurations with inherent
dissipative properties that may play an important role in the coronal heating.
An interesting feature observed is the generation of different types of arcades
with the variation of a single parameter characterizing the relaxed state.
Also, recent observations with the LASCO coronagraph on board the SOHO
spacecraft suggest that the helmet streamers originating from the sun may have
an internal triple-arcade structure. The two-fluid relaxed state obtained here
is also seen to support such structures.


title:
Computationally-efficient Expressions for the Collision Efficiency
  Between Electrically Charged Aerosol Particles and Cloud Droplets

abstract:
  A multifactor parameterization is described to permit the efficient
calculation of collision efficiency (E) between electrically charged aerosol
particles and neutral cloud droplets in numerical cloud and climate models. The
four parameter representation summarizes the results obtained from a detailed
microphysical model of collision efficiency, which accounts for the different
forces acting on the aerosol in the path of falling cloud droplets. The
parameterizations range of validity is for aerosol particle radius 0.4 to 10
micron, aerosol particle density 1 to 2.0 g.cm-3, aerosol particle charge from
neutral to 100 elementary charges and drop radii 18.55-142 micron. It yields
collision efficiencies well within an order of magnitude of the detailed models
values, from a data set of of 3978 E values. 95 percent of these values have
modeled to parameterized ratios between 0.5 and 1.5 for aerosol particle size
range 0.4 to 2 micron and about 96 percent in the second size range. This
parameterization speeds up the collision efficiency calculation by a factor of
about 103, as compared with the original microphysical model, permitting the
inclusion of electric charge effects in numerical cloud and climate models. In
the following pages parameterization code in C language is provided for
readymade use.


title:
Enrico Fermi e Ettore Majorana: continuita' e rinnovamento
  nell'insegnamento della Fisica teorica

abstract:
  In 1927, just after he obtained a full professorship, Enrico Fermi delivered
his first course on Theoretical Physics at the Institute of Physics in Rome.
The following year Edoardo Amaldi, Emilio Segre' and Ettore Majorana became
students of that course. The lectures given in 1927-28, whose content may be
easily reconstructed, probably had a deep impact in forming such young
students, who participated actively in the Physics researches carried on in
Rome soon after. In this perspective, the case of Ettore Majorana is certainly
the most important one: as a lecturer, in 1933-36 he planned to give three
advanced Physics courses in Rome, before obtaining his full professorship in
Theoretical Physics "for high and well-deserved repute" in 1937. From the
analysis of the lectures he delivered in Naples in 1938, we can conclude that,
in part, Majorana referred to the Fermi lectures he followed as a student, but
he also introduced some advanced (for that time) topics, rendering his course a
very modern one. Much of these frontier topics were already cited in the
programmes of the mentioned three courses he presented few years earlier.

categories: physics.hist-ph hep-ph physics.ed-ph physics.pop-ph


title:
Nanoseconds field emitted current pulses from ZrC needles and field
  emitter arrays

abstract:
  The properties of the electron source define the ultimate limit of the beam
quality in linear accelerators like Free Electron Lasers (FEL). The goal is to
develop an electron gun delivering beam emittance lower than current state of
the art. Such a gun should reduce the cost and size of an X-ray Free Electron
Laser (XFEL). In this paper we present two concepts of field emitter cathodes
which could potentially produce low emittance beam. The first challenging
parameter for such cathode is to emit peak current as high as 5 A. This is the
minimum current requirement for the XFEL concept from Paul Scherrer Institut.1
Maximum current of 0.12 A and 0.58 A have been reached respectively with field
emitter arrays (FEA) and single needle cathodes. Laser assisted field emission
gave encouraging results to reach even higher peak current and to pre-bunch the
beam.


title: Large-amplitude Electron Oscillations in a Plasma Slab

abstract:
  Nonlinear oscillations within a plasma slab are analyzed. Two types of
solutions are found, depending on the initial value of the electron density.
The first represents regular oscillations within the plasma slab, while the
second gives rise to explosive growth at the slab centre or at the edges. The
results are discussed.


title:
Demonstration of a Cold Atom Fountain Electron Electric Dipole Moment
  Experiment

abstract:
  A Cs fountain electron electric dipole moment (EDM) experiment using
electric-field quantization is demonstrated. With magnetic fields reduced to
200 pT or less, the electric field lifts the degeneracy between hyperfine
levels of different|mF| and, along with the slow beam and fountain geometry,
suppresses systematics from motional magnetic fields. Transitions are induced
and the atoms polarized and analyzed in field-free regions. The feasibility of
reaching a sensitivity to an electron EDM of 2 x 10 exp(-50) C-m [1.3 x 10
exp(-29) e-cm] in a cesium fountain experiment is discussed.


title:
Observation of "volume reflection" effect in crystal collimation
  experiments

abstract:
  Strong effect of beam coherent scattering ("reflection") in a field of bent
crystal is observed in crystal collimation experiments performed with heavy
ions and protons at RHIC and started at Tevatron collider. Detailed simulation
using Monte Carlo code CATCH is done in order to understand the observations
and relate them to the physics of beam coherent scattering in crystal. A.M.
Taratin and S.A. Vorobiev predicted the effect of beam "volume reflection" in
bent crystals in 1987. The presented data is the first manifestation of this
new physical phenomenon in experiment.


title:
Long Response to Scheuer-Yariv: "A Classical Key-Distribution System
  based on Johnson (like) noise - How Secure?", physics/0601022

abstract:
  This is the longer (partially unpublished) version of response; the shorter
version (http://arxiv.org/abs/physics/0605013) is published in Physics Letters
A. We point out that the claims in the comment-paper of Scheuer and Yariv are
either irrelevant or incorrect. We first clarify what the security of a
physically secure layer means. The idealized Kirchoff-loop-Johnson-like-noise
(KLJN) scheme is totally secure therefore it is more secure than idealized
quantum communication schemes which can never be totally secure because of the
inherent noise processes in those communication schemes and the statistical
nature of eavesdropper detection based on error statistics. On the other hand,
with sufficient resources, a practical/non-ideal realization of the KLJN cipher
can arbitrarily approach the idealized limit and outperform even the idealized
quantum communicator schemes because the non-ideality-effects are determined
and controlled by the design. The cable resistance issue analyzed by Scheuer
and Yariv is a good example for that because the eavesdropper has insufficient
time window to build a sufficient statistics and the actual information leak
can be designed. We show that Scheuer's and Yariv's numerical result of 1%
voltage drop supports higher security than that of quantum communicators.
Moreover, choosing thicker or shorter wires can arbitrarily reduce this voltage
drop further; the same conclusion holds even according to the equations of
Scheuer and Yariv.


title:
Model of horizontal stress in the Aigion10 well (Corinth) calculated
  from acoustic body waves

abstract:
  In this paper we try to deduce the in situ stresses from the monopole
acoustic waves of the well AIG10 between 689 and 1004 meters in depth (Corinth
Golf). This borehole crosses competent sedimentary formations (mainly
limestone), and the active Aigion fault between 769 and 780 meters in depth.
This study is the application of two methods previously described by the author
who shows the relationships between in situ horizontal stresses, and (i) the
presence or absence of double body waves, (ii) the amplitude ratios between S
and P waves (Rousseau, 2005a,b). The full waveforms of this well exhibit two
distinct domains separated by the Aigion fault. Within the upper area the three
typical waves (P, S and Stoneley) may appear, but the S waves are not numerous,
and there is no double body wave, whereas within the lower area there are
sometimes double P waves, but no S waves. From those observations, we conclude
that the stress domain is isotropic above the Aigion fault, and anisotropic
below, which is consistent with conclusions drawn by authors from other kinds
of data. The calculation applied to the characteristics of the double P waves
suggests that this horizontal stress anisotropy is very high, up to 190 % with
the maximum horizontal stress superior to 100 MPa and the minimum horizontal
stress close to zero at 939 meters in depth. The amplitude ratios between the S
and P wave indicate a very strong compression - which is isotropic - above the
Aigion fault.


title:
Market efficiency and the long-memory of supply and demand: Is price
  impact variable and permanent or fixed and temporary?

abstract:
  In this comment we discuss the problem of reconciling the linear efficiency
of price returns with the long-memory of supply and demand. We present new
evidence that shows that efficiency is maintained by a liquidity imbalance that
co-moves with the imbalance of buyer vs. seller initiated transactions. For
example, during a period where there is an excess of buyer initiated
transactions, there is also more liquidity for buy orders than sell orders, so
that buy orders generate smaller and less frequent price responses than sell
orders. At the moment a buy order is placed the transaction sign imbalance
tends to dominate, generating a price impact. However, the liquidity imbalance
rapidly increases with time, so that after a small number of time steps it
cancels all the inefficiency caused by the transaction sign imbalance, bounding
the price impact. While the view presented by Bouchaud et al. of a fixed and
temporary bare price impact is self-consistent and formally correct, we argue
that viewing this in terms of a variable but permanent price impact provides a
simpler and more natural view. This is in the spirit of the original conjecture
of Lillo and Farmer, but generalized to allow for finite time lags in the build
up of the liquidity imbalance after a transaction. We discuss the possible
strategic motivations that give rise to the liquidity imbalance and offer an
alternative hypothesis. We also present some results that call into question
the statistical significance of large swings in expected price impact at long
times.


title:
Time evolution of spin state of radical ion pair in microwave field: An
  analytical solution

abstract:
  The paper reports an exact solution for the problem of spin evolution of
radical ion pair in static magnetic and resonant microwave field taking into
account Zeeman and hyperfine interactions and spin relaxation. The values of
parameters that provide one of the four possible types of solution are
analysed. It is demonstrated that in the absence of spin relaxation, besides
the zero field invariant an invariant at large amplitudes of the resonant
microwave field can be found. The two invariants open the possibility for
simple calculation of microwave pulses to control quantum state of the radical
pair. The effect of relaxation on the invariants is analysed and it is shown
that changes in the high field invariant are induced by phase relaxation.


title:
Changes in the fine structure of stochastic distributions as a
  consequence of space-time fluctuations

abstract:
  Earlier we showed that the fine structure of the spectrum of amplitude
variations in the results of measurements of the processes of different nature
(in other words, the fine structure of the dispersion of results or the pattern
of the corresponding histograms) is subject to macroscopic fluctuations,
changing regularly with time. These changes indicate that the dispersion of
results that remains after all artifacts are excluded inevitably accompanies
any measurements and reflects very basic features of our world. In our
research, we have come to the conclusion that this dispersion of results is the
effect of space-time fluctuations, which, in their turn, are caused by the
movement of the measured object in an anisotropic gravitational field. Among
other things, this conclusion means that the examination of the detailed
pattern of distributions obtained from the results of measurement of the
dynamics of processes of different nature discovers laws, which cannot be
revealed with traditional methods for the analysis of time series. These
assertions are based on the results of long-term experimental investigations
conducted for many decades. The major part of these results, starting with
1958, is published in Russian. The goal of this paper is to give a brief review
of those results and provide corresponding references. The most general
conclusion of our research is the evidence that the fine structure of
stochastic distributions is not accidental. In other words, noncasual is the
pattern of histograms plotted from a rather small number of the results of
measurement of the dynamics of processes of different nature, from the
biochemical reactions and noise in the gravitational antenna to the
alpha-decay.


title:
Auger Spectra and Different Ionic Charges Following 3s, 3p and 3d
  Sub-Shells Photoionization of Kr Atoms

abstract:
  The decay of inner-shell vacancy in an atom through radiative and
non-radiative transitions leads to final charged ions. The de-excitation decay
of 3s, 3p and 3d vacancies in Kr atoms are calculated using Monte-Carlo
simulation method. The vacancy cascade pathway resulted from the de-excitation
decay of deep core hole in 3s subshell in Kr atoms is discussed. The generation
of spectator vacancies during the vacancy cascade development gives rise to
Auger satellite spectra. The last transitions of the de-excitation decay of 3s,
3p and 3d holes lead to specific charged ions. Dirac-Fock-Slater wave functions
are adapted to calculate radiative and non-radiative transition probabilities.
The intensity of Kr^{4+} ions are high for 3s hole state, whereas Kr^{3+} and
Kr^{2+} ions have highest intensities for 3p and 3d hole states, respectively.
The present results of ion charge state distributions agree well with the
experimental data.


title:
An Empirical Approach to the Bond Additivity Model in Quantitative
  Interpretation of Sum Frequency Generation Vibrational Spectra

abstract:
  A complete empirical approach from known Raman and IR spectra is used to make
corrections to the bond additivity model for quantitative interpretation of Sum
Frequency generation Vibrational Spectra (SFG-VS) from molecular interfaces.
This empirical correction successfully addresses the failures of the simple
bond additivity model. This empirical approach not only provides new
understandings of the effectiveness and limitations of the bond additivity
model, but also provides a practical roadmap for its application in SFG-VS
studies of molecular interfaces.


title:
Buckling transition in icosahedral shells subjected to volume
  conservation constraint and pressure: relations to virus maturation

abstract:
  Minimal energy shapes of closed, elastic shells with twelve pentagonal
disclinations introduced in otherwise hexagonally coordinated crystalline
lattice are studied. The geometry and the total energy of shells are studied as
a function of the elastic properties of the material they are made of.
Particular emphasis is put on the buckling transition of the shells, that is a
strong preference of the shell shapes to 'buckle out' in spatial regions close
to the pentagonal disclinations for certain range of the elastic parameters of
the problem. The transition effectively increases the mean square aspherity of
shapes, making them look more like an icosahedron, rather than a sphere which
is a preferred shape prior to the onset of the transition. The properties of
the buckling transition are studied in cases when (i) the total volume enclosed
by the elastic shell has to be fixed and when (ii) there is an internal
pressure acting on the shell. This may be related to maturation process in
non-enveloped dsDNA viruses, where the insertion of the genetic material in a
pre-formed protein shell (viral coating) may effectively impose the fixed
volume and/or pressure constraint. Several scenarios that may explain the
experimentally observed feature of mature viruses being more aspherical
(facetted) from their immature precursors are discussed and new predictions for
the elastic properties of viral coatings are obtained on the basis of the
presented studies.


title: A Density Functional Study of Bare and Hydrogenated Platinum Clusters

abstract:
  We perform density functional theory calculations using Gaussian
atomic-orbital methods within the generalized gradient approximation for the
exchange and correlation to study the interactions in the bare and hydrogenated
platinum clusters. The minimum-energy structures, binding energies, relative
stabilities, vibrational frequencies and the highest occupied and lowest
unoccupied molecular-orbital gaps of Pt_nH_m (n=1-5, m=0-2) clusters are
calculated and compared with previously studied pure platinum and hydrogenated
platinum clusters. We investigate any magic behavior in hydrogenated platinum
clusters and find that Pt_4H_2 is more stable than its neighboring sizes. Our
results do not agree with a previous conclusion that 3D geometries of Pt
tetramer and pentamer are unfavored. On the contrary, the lowest energy
structure of Pt_4 is found to be a distorted tetrahedron and that of Pt_5 is
found to be a bridge site capped tetrahedron which is a new global minimum for
Pt_5 cluster. The successive addition of H atoms to Pt_n clusters leads to an
oscillatory change in the magnetic moment of Pt_3 - Pt_5 clusters.


title: Aspects of Cooling at the TRI$\mu$P Facility

abstract:
  The Tri$\mu$P facility at KVI is dedicated to provide short lived radioactive
isotopes at low kinetic energies to users. It comprised different cooling
schemes for a variety of energy ranges, from GeV down to the neV scale. The
isotopes are produced using beam of the AGOR cyclotron at KVI. They are
separated from the primary beam by a magnetic separator. A crucial part of such
a facility is the ability to stop and extract isotopes into a low energy
beamline which guides them to the experiment. In particular we are
investigating stopping in matter and buffer gases. After the extraction the
isotopes can be stored in neutral atoms or ion traps for experiments. Our
research includes precision studies of nuclear $\beta$-decay through
$\beta$-$\nu$ momentum correlations as well as searches for permanent electric
dipole moments in heavy atomic systems like radium. Such experiments offer a
large potential for discovering new physics.


title: sPlot: A Quick Introduction

abstract:
  The paper advocates the use of a statistical tool dedicated to the
exploration of data samples populated by several sources of events. This new
technique, called sPlot, is able to unfold the contributions of the different
sources to the distribution of a data sample in a given variable. The sPlot
tool applies in the context of a Likelihood fit which is performed on the data
sample to determine the yields of the various sources.


title:
Piecewise continuous distribution function method and ultrasound at half
  space

abstract:
  The system of hydrodynamic-type equations, derived by two-side distribution
function for a stratified gas in gravity field is applied to a problem of
ultrasound propagation and attenuation. The background state and linearized
version of the obtained system is studied and compared with the Navier-Stokes
one at arbitrary Knudsen numbers. The WKB solutions for ultrasound in a
stratified medium are constructed in explicit form. The problem of a generation
by a moving plane in a rarefied gas is explored and used as a test while
compared with experiment.


title: Parallel computing for 4-atomic molecular dynamics calculations

abstract:
  We report the results of intensive numerical calculations for four atomic
H2+H2 energy transfer collision. A parallel computing technique based on
LAM/MPI functions is used. In this algorithm, the data is distributed to the
processors according to the value of the momentum quantum number J and its
projection M. Most of the work is local to each processor. The topology of the
data communication is a simple star. Timings are given and the scaling of the
algorithm is discussed. Two different recently published potential energy
surfaces for the H2-H2 system are applied. New results obtained for the state
resolved excitation-deexcitation cross sections and rates valuable for
astrophysical applications are presented. Finally, more sophisticated
extensions of the parallel code are discussed.


title:
Preferential attachment in the growth of social networks: the case of
  Wikipedia

abstract:
  We present an analysis of the statistical properties and growth of the free
on-line encyclopedia Wikipedia. By describing topics by vertices and hyperlinks
between them as edges, we can represent this encyclopedia as a directed graph.
The topological properties of this graph are in close analogy with that of the
World Wide Web, despite the very different growth mechanism. In particular we
measure a scale--invariant distribution of the in-- and out-- degree and we are
able to reproduce these features by means of a simple statistical model. As a
major consequence, Wikipedia growth can be described by local rules such as the
preferential attachment mechanism, though users can act globally on the
network.


title: Renner-Teller effects in HCO+ dissociative recombination

abstract:
  A theoretical description of the dissociative recombination process for the
HCO+ ion suggests that the nonadiabatic Renner-Teller coupling between
electronic and vibrational degrees of freedom plays an important role. This
finding is consistent with a recent study of this process for another
closed-shell molecule, the H3+ ion, where Jahn-Teller coupling was shown to
generate a relatively high rate. The cross section obtained here for the
dissociative recombination of HCO+exhibits encouraging agreement with a
merged-beam experiment.


title:
Orthodoxy and Heterodoxy in the Research on the Foundations of Quantum
  Physics: E. P. Wigner's Case

abstract:
  Dealing with Eugene Wigner's ideas on the measurement procedure in quantum
physics and unearthing the controversy that pitted him against supporters of
the interpretation of complementarity, I will show how Wigner and his followers
contributed to the defeat of a seemingly unshakeable consensus. In fact,
although he intended to defend what seemed to him to be orthodoxy, he himself
became a heterodox. I suggest that Wigner's conjectures on the role of
consciousness in physical phenomena were not fruitful and were discarded, being
today part of the history of physics rather than physics proper. However, his
ideas and actions left an indelible mark on the physics of the second half of
the 20th century. Namely, he formulated his ideas in opposition to the
Copenhagen monocracy, which held a stronghold on the interpretation of quantum
physics until the late 1960s; he stressed the unsolved status of the
measurement problem; and he effectively defended his ideas and supported those
who were willing to investigate the foundations of quantum physics. He thus
contributed to the creation of a new field of physical research, that of the
foundations of quantum physics, which attributed a higher scientific status to
the old controversy on the interpretations and foundations of this theory. This
new field has had to deal with important theoretical, experimental, and
philosophical issues, and significant repercussions have arisen in the last
decades.


title: Comment on A.-L. Barabasi, Nature 435 207-211 (2005)

abstract:
  The purpose of this communication is twofold. First, it clarifies the origin
of the power law obtained in the computer simulations presented in A.-L.
Barabasi, Nature 435 207-211 (2005) as well as presenting a statistically more
sound analysis of the experimental email data used in that paper and in [4].
The second purpose is to clarify the origin of the the suggestion of power law
probability distribution for the response times of humans presented with a
piece of new information either as a news event or through the reception of an
email.


title: Pancharatnam Phase and Photon Polarization Optics

abstract:
  Parallel transport of a vector around a closed curve on the surface of a
sphere leads to a direction holonomy which can be related with a geometric
phase that is equal to the solid angle subtended by the closed curve. Since
Pancharatnam phase is half of the solid angle subtended by the polarization
cycle on the Poincare sphere, quantum parallel transport law takes recourse o
spin-half wave function to obtain this result. A critique is offered on this
factor of half anomaly in the geometric phase, and a natural resolution using
Riemann sphere polarization representation is suggested. It is argued that spin
angular momentum of photon is fundamental in polarization optics, and new
insights are gained based on the hypothesis that two helicity states correspond
to two distinct species of photon. This approach leads to the concept of a
physical Poincare sphere: nonlinearity and jumps in the Pancharatnam phase find
a simple physical explanation while novel features pertaining to the discrete
and pulsating sphere are predicted. Paired photon spin zero structure of
unpolarized light is also discussed. An outline of possible experimental tests
is presented.


title: Bragg-type soliton mirror

abstract:
  We study soliton reflection/transmission at the interface between uniform
medium and the optical lattice with focusing Kerr nonlinearity. We reveal that
such interfaces afford rich new opportunities for controlling the reflection
and transmission coefficients and nonlinear Snell law, the key control
parameters being the spatial frequency and depth of the lattice.


title: Progress with a Universal Theory of Relativity

abstract:
  In this presentation, I will summarize the present status of the developments
with a Universal Theory of Relativity \cite{smw-utr}. Some general challenges
to be overcome will also be discussed.


title: Community Structure in the United States House of Representatives

abstract:
  We investigate the networks of committee and subcommittee assignments in the
United States House of Representatives from the 101st--108th Congresses, with
the committees connected by ``interlocks'' or common membership. We examine the
community structure in these networks using several methods, revealing strong
links between certain committees as well as an intrinsic hierarchical structure
in the House as a whole. We identify structural changes, including additional
hierarchical levels and higher modularity, resulting from the 1994 election, in
which the Republican party earned majority status in the House for the first
time in more than forty years. We also combine our network approach with
analysis of roll call votes using singular value decomposition to uncover
correlations between the political and organizational structure of House
committees.

categories: physics.soc-ph cond-mat.stat-mech cs.MA nlin.AO physics.data-an


title: Motion of a testing particle in gravitational field of a ring

abstract:
  The planar motion of a testing body in the field of gravity of the massive
ring is studied. The "perihelion" precession due to non-relativistic reasons is
demonstrated on this simple example of planar motion in the radially symmetric
(in the plane of motion) situation. The ring as the source of the gravitational
field can serve as the toy model for quasi-planar sources of gravity appearing
in the galactic dynamics, etc. The results are used to estimate the real
perihelion shift of the planet Mercury due to gravitational quadrupole moment
of the Sun.


title: The rotation of galaxies as a consequence of a rotation of the Universe

abstract:
  Assuming a suitable rotation of the Universe as a whole, we can attribute the
rotation of galaxies to it. Using Lagrangian Mechanics we then can find the
equations governing the rotation of a galaxy. We find in this way the azimuthal
equation, and we find its first integral. Then we derive from it the law of
differrential rotation of galaxies, and we plot it. We also present the
resulting flat rotation curve, which is found to resemble remarkably the
observed rotation curves.


title: Remarks on gravity, entropy, and information

abstract:
  This is a partially survey collection of material on gravity, entropy, and
information with some new heuristic results related to the WDW equation.


title:
The rest masses of the electron and muon and of the stable mesons and
  baryons

abstract:
  The rest masses of the electron, the muon and of the stable mesons and
baryons can be explained, within 1% accuracy, with the standing wave model,
which uses only photons, neutrinos, charge and the weak nuclear force. We do
not need hypothetical particles for the explanation of the masses of the
electron, muon, mesons and baryons.
  We can also explain the charge of the electron, the spin of the electron, of
the muon and of the stable baryons, without any additional assumption. We also
have determined the rest masses of the electron-, muon- and tau neutrinos and
found that the mass of the electron neutrino is equal to the fine structure
constant times the mass of the muon neutrino.


title: Universal Relativity and Its Mathematical Requirements

abstract:
  In this presentation, I review physical principles behind a recently proposed
\cite{smw-utr} Universal Theory of Relativity and speculate on the mathematical
requirements implied by these physical principles. Some unresolved issues will
also be discussed.


title: Networking Effects on Cooperation in Evolutionary Snowdrift Game

abstract:
  The effects of networking on the extent of cooperation emerging in a
competitive setting are studied. The evolutionary snowdrift game, which
represents a realistic alternative to the well-known Prisoner's Dilemma, is
studied in the Watts-Strogatz network that spans the regular, small-world, and
random networks through random re-wiring. Over a wide range of payoffs, a
re-wired network is found to suppress cooperation when compared with a
well-mixed or fully connected system. Two extinction payoffs, that characterize
the emergence of a homogeneous steady state, are identified. It is found that,
unlike in the Prisoner's Dilemma, the standard deviation of the degree
distribution is the dominant network property that governs the extinction
payoffs.


title: Gravitational waves from BBH-systems? A (doubly) vain quest

abstract:
  The theoretical reasons at the root of LIGO's experimental failure in
searching gravitational waves (GW's) from binary black hole (BBH) inspirals.


title: Possible Negative Pressure States in the Evolution of the Universe

abstract:
  Hydrodynamic derivation of the entrainment of matter induced by a surface
elastic wave propagating along the flexible vacuum-matter interface is
conducted by considering the nonlinear coupling between the interface and the
rarefaction effect. The critical reflux values associated with the product of
the second-order (unit) body forcing and the Reynolds number (representing the
viscous dissipations) decrease as the Knudsen number (representing the
rarefaction measure) increases from zero to 0.1. We obtained the critical
bounds for matter-freezed or zero-volume-flow-rate states corresponding to
specific Reynolds numbers (ratio of wave inertia and viscous dissipation
effects) and wave numbers which might be linked to the evolution of the
Universe. Our results also show that for positive evolution of the matter (the
maximum speed of the matter (gas) appears at the center-line) there might be
existence of negative pressure.


title:
Universal Theory of Relativity and the "Unification" of Fundamental
  Physical Interactions

abstract:
  The ``unification'' of fundamental physical forces (interactions) imagines a
``single'' conceptual entity using which {\em all} the observable or physical
phenomena, {\em ie}, changes to physical bodies, would be suitably describable.
The physical, conceptual and mathematical, framework which achieves this is
that of the recently proposed Universal Theory of Relativity \cite{smw-utr}.
Here, we argue that the mathematical framework required to achieve the
``unification'' should be that of the general Category Theory. There are
certain unanswered mathematical questions arising out of this context. In the
sequel, we also point out these issues for the wider attention.


title: Indian Contributions to High Energy Physics in the 20th Century

abstract:
  The inward bound path of discovery unravelling the mysteries of matter and
the forces that hold it together has culminated at the end of the twentieth
century in a theory of the Fundamental Forces of Nature based on Nonabelian
Gauge Fields, called the Standard Model of High Energy Physics. In this article
we trace the historical development of the ideas and the experimental
discoveries on which this theory is based. We also mark significant Indian
contributions wherever possible. Finally we have a glimpse at future
developments. An Appendix on more Indian contributions is added at the end.


title:
Einstein et la mecanique quantique - Quelques reperes, quelques
  surprises

abstract:
  Even if Einstein brought major contributions as a founder of quantum
mechanics, he remained deeply unsatisfied with the bases of this structure he
knew to be so efficient for physics. His critics are often known through his
numerous controversies wih N. Bohr for a few decades. It has long been
suggested that his critics were obsolete and came from an aging man and that it
was more a question of philosophy anyway. After J. Bell's contribution however
it was claimed that the debate could be closed by an experimental proof, a
strange experimental intrusion in philosophy or a strange philosophy. Finally,
the experiment being performed, in particular in Orsay with the repeatedly
successful experiments of A. Aspect, it was claimed that N. Bohr won. Would the
debate be closed? Today and fifty years after his death, it seems that
Einstein's critics to quantum mechanics are being regarded differently. Why is
it so? Is it due to physics coming back to the debate? It will be attempted to
accurately report Einstein's writings on the matter and to find elements of
answer to the raised questions.


title: Gas Purity effect on GEM Performance in He and Ne at Low Temperatures

abstract:
  The performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne, He+H2
and Ne+H2 was studied at temperatures in the range of 3-293 K. This paper
reports on previously published measurements and additional studies on the
effects of the purity of the gases in which the GEM performance is evaluated.
In He, at temperatures between 77 and 293 K, triple-GEM structures operate at
rather high gains, exceeding 1000. There is an indication that this high gain
is achieved through the Penning effect as a result of impurities in the gas. At
lower temperatures the gain-voltage characteristics are significantly modified
probably due to the freeze-out of these impurities. Double-GEM and single-GEM
structures can operate down to 3 K at gains reaching only several tens at a gas
density of about 0.5 g/l; at higher densities the maximum gain drops further.
In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in
Ne at low temperatures can be re-established in Penning mixtures of Ne+H2: very
high gains, exceeding 104, have been obtained in these mixtures at 30-77 K, at
a density of 9.2 g/l which corresponds to saturated Ne vapor density at 27 K.
The addition of small amounts of H2 in He also re-establishes large GEM gains
above 30 K but no gain was observed in He+H2 at 4 K and a density of 1.7 g/l
(corresponding to roughly one-tenth of the saturated vapor density). These
studies are, in part, being pursued in the development of two-phase He and Ne
detectors for solar neutrino detection.


title:
Cytoskeleton influence on normal and tangent fluctuation modes in the
  red blood cells

abstract:
  We argue that the paradoxal softness of the red blood cells (RBC) in
fluctuation spectra experiments is apparent. We show that the effective surface
shear modulus $\mu_s$ of the RBC obtained from fluctuation data and that
measured in static deformation experiments have the same order of magnitude. A
simple micromechanical model of the RBC developped for this purpose accounts
for the influence of a finite-thickness cytoskeleton on the fluctuations of the
composite membrane-cytoskeleton system. The spectrin network cytoskeleton with
the bulk shear modulus estimated as $\mu\approx105\div 165$ Pa contributes to
both normal and tangent fluctuations of the system and confines the
fluctuations of the lipid membrane. The ratio of mean square amplitudes of the
RBC normal and tangent fluctuations $<X_n^2> /< X_t^2>$ calculated in the frame
of the model is 2-3 orders of magnitude smaller that it is in the free membrane
with the same bending and shear moduli


title: Z Theory and its Quantum-Relativistic Operators

abstract:
  The view provided by Z theory, based on its quantum-relativistic operators,
is an integrated picture of the micro and macro quantities relationships. The
axiomatic formulation of the theory is presented in this paper. The theory
starts with the existence of the wave function, the existence of three
fundamental constants h, c and G as well as the physical quantity Rc (the
radius of the space-time continuum) plus the definition of a general form for
the quantum-relativistic functional operators. Using such starting point the
relationships between relativity, quantum mechanics and cosmological quantities
can be clarified.


title: Delta Hedged Option Valuation with Underlying Non-Gaussian Returns

abstract:
  The standard Black-Scholes theory of option pricing is extended to cope with
underlying return fluctuations described by general probability distributions.
A Langevin process and its related Fokker-Planck equation are devised to model
the market stochastic dynamics, allowing us to write and formally solve the
generalized Black-Scholes equation implied by dynamical hedging. A systematic
expansion around a non-perturbative starting point is then implemented,
recovering the Matacz's conjectured option pricing expression. We perform an
application of our formalism to the real stock market and find clear evidence
that while past financial time series can be used to evaluate option prices
before the expiry date with reasonable accuracy, the stochastic character of
volatility is an essential ingredient that should necessarily be taken into
account in analytical option price modeling.