title: Thermodynamics of natural images

abstract:
  The scale invariance of natural images suggests an analogy to the statistical
mechanics of physical systems at a critical point. Here we examine the
distribution of pixels in small image patches and show how to construct the
corresponding thermodynamics. We find evidence for criticality in a diverging
specific heat, which corresponds to large fluctuations in how "surprising" we
find individual images, and in the quantitative form of the entropy vs. energy.
The energy landscape derived from our thermodynamic framework identifies
special image configurations that have intrinsic error correcting properties,
and neurons which could detect these features have a strong resemblance to the
cells found in primary visual cortex.


title: Pieri-Type Formulas for the Nonsymmetric Macdonald Polynomials

abstract:
  In symmetric Macdonald polynomial theory the Pieri formula gives the
branching coefficients for the product of the rth elementary symmetric function
and the Macdonald polynomial. In this paper we give the nonsymmetric analogues
for the cases r=1 and r=n-1. We do this by first deducing the the decomposition
for the product of any nonsymmetric Macdonald polynomial with a linear function
in terms of nonsymmetric Macdonald polynomials. As a corollary of finding the
branching coefficients of the product of the first elementary function with a
nonsymmetric Macdonald polynomial we evaluate the generalised binomial
coefficients associated with the nonsymmetric Macdonald polynomials for
|u|=|v|+1.


title:
A construction of Einstein-Weyl spaces via LeBrun-Mason type twistor
  correspondence

abstract:
  We construct infinitely many Einstein-Weyl structures on $S^2 \times R$ of
signature (-++) which is sufficiently close to the model case of constant
curvature, and whose space-like geodesics are all closed. Such structures are
obtained from small perturbations of the diagonal of $CP^1 \times CP^1$ using
the method of LeBrun-Mason type twistor theory. The geometry of constructed
Einstein-Weyl space is well understood from the configuration of holomorphic
disks. We also review Einstein-Weyl structures and their properties in the
former half of this article.


title: Note on geodesic rays tamed by simple test configurations

abstract:
  In this short note, we give a new proof of a theorem of Arezzo-Tian on the
existence of smooth geodesic rays tamed by a special degeneration.


title: Leptogenesis in the extension of the Zee-Babu model

abstract:
  We demonstrate that the extension of the Zee-Babu model can generate not only
the small neutrino masses but also the baryon number asymmetry in the universe.
In particular, we show that the scale of the singlet scalar responsible for the
leptogenesis can be of order 1 TeV, that can be tested at the LHC and ILC. We
also considered the possible minimal extension of this model to generate the
dark matter.


title:
Optimal positive-operator-valued measures for unambiguous state
  discrimination

abstract:
  Optimization of the mean efficiency for unambiguous (or error
free)discrimination among $N$ given linearly independent nonorthogonal states
should be realized in a way to keep the probabilistic quantum mechanical
interpretation. This imposes a condition on a certain matrix to be positive
semidefinite. We reformulated this condition in such a way that the conditioned
optimization problem for the mean efficiency was reduced to finding an
unconditioned maximum of a function defined on a unit $N$-sphere for
equiprobable states and on an $N$-ellipsoid if the states are given with
different probabilities. We established that for equiprobable states a point on
the sphere with equal values of Cartesian coordinates, which we call symmetric
point, plays a special role. Sufficient conditions for a vector set are
formulated for which the mean efficiency for equiprobable states takes its
maximal value at the symmetric point. This set, in particular, includes
previously studied symmetric states. A subset of symmetric states, for which
the optimal measurement corresponds to a POVM requiring a one-dimensional
ancilla space is constructed. We presented our constructions of a POVM suitable
for the ancilla space dimension varying from 1 till $N$ and the Neumark's
extension differing from the existing schemes by the property that it is
straightforwardly applicable to the case when it is desirable to present the
whole space system + ancilla as the tensor product of a two-dimensional ancilla
space and the $N$-dimensional system space.


title:
Enhanced p-Mode Absorption seen near the Sunspot Umbral-Penumbral
  Boundary

abstract:
  We investigate p-mode absorption in a sunspot using SOHO/MDI high-resolution
Doppler images. The Doppler power computed from a three and a half hour data
set is used for studying the absorption in a sunspot. The result shows an
enhancement in absorption near the umbral-penumbral boundary of the sunspot. We
attempt to relate the observed absorption with the magnetic field structure of
the sunspot. The transverse component of the potential field is computed using
the observed SOHO/MDI line-of-sight magnetograms. A comparison of the power map
and the computed potential field shows enhanced absorption near the
umbral-penumbral boundary where the computed transverse field strength is
higher.


title:
Dynamics of ferroelectric nano cluster in BaTiO3 observed as a real time
  correlation between two soft X-ray laser pulses

abstract:
  We carry out a theoretical investigation to clarify the dynamic property of
photo-created nano-sized ferroelectric cluster observed in the paraelectric
BaTiO3 as a real time correlation of speckle pattern between two soft X-ray
laser pulses, at just above the paraelectric-ferroelectric phase transition
temperature. Based on a model with coupled soft X-ray photon and ferroelectric
phonon mode, we study the time dependence of scattering probability by using a
perturbative expansion approach. The cluster-associated phonon softening as
well as central peak effects are well reproduced in the phonon spectral
function via quantum Monte Carlo simulation. Besides, it is found that the time
dependence of speckle correlation is determined by the relaxation dynamics of
ferroelectric clusters. Near the transition point, cluster excitation is
stable, leading to a long relaxation time. While, at high temperature, cluster
structure is subject to the thermal fluctuation, ending up with a short
relaxation time.


title:
"Magnetic" components of gravitational waves and response functions of
  interferometers

abstract:
  Recently, arising from an enlighting analysis of Baskaran and Grishchuk in
Class. Quant. Grav. 21, 4041-4061 (2004), some papers in the literature have
shown the presence and importance of the so-called "magnetic" components of
gravitational waves (GWs), which have to be taken into account in the context
of the total response functions of interferometers for GWs propagating from
arbitrary directions. In Int. Journ. Mod. Phys. A 22, 13, 2361-2381 (2007) and
Int. J. Mod. Phys. D 16, 9, 1497-1517 (2007) accurate response functions for
the Virgo and LIGO interferometers have been analysed. However, some results
which have been shown in Int. Journ. Mod. Phys. A 22, 13, 2361-2381 (2007) look
in contrast with the results which have been shown in Int. J. Mod. Phys. D 16,
9, 1497-1517 (2007). In fact, in Int. Journ. Mod. Phys. A 22, 13, 2361-2381
(2007) it was claimed that the "magnetic" component of GWs could, in principle,
extend the frequency range of Earth based interferometers, while in Int. J.
Mod. Phys. D 16, 9, 1497-1517 (2007) such a possibility has been banned. This
contrast has been partially solved in the Proceedings of the XLIInd Rencontres
de Moriond, Gravitational Waves and Experimental Gravity, La Thuile, Val
d'Aosta Italy (March 12-18 2007). The aim of this review paper is to re-analyse
all the framework of the "magnetic" components of GWs with the goal of solving
the mentioned contrast in definitive way. Accurate response funtions for the
Virgo and LIGO interferometers will be also re-discussed in detail.


title: A Theorem of Beurling and H\"ormander on Damek-Ricci Spaces

abstract:
  This paper has been withdrawn by the authors, due to the requirement of the
Journal where a modified version will be published.


title: A Morita theorem for dual operator algebras

abstract:
  We prove that two dual operator algebras are weak$^*$ Morita equivalent if
and only if they have equivalent categories of dual operator modules via
completely contractive functors which are also weak$^*$-continuous on
appropriate morphism spaces. Moreover, in a fashion similar to the operator
algebra case, we characterize such functors as the module normal Haagerup
tensor product with an appropriate weak$^*$ Morita equivalence bimodule. We
also develop the theory of the $W^*$-dilation, which connects the
non-selfadjoint dual operator algebra with the $W^*$-algebraic framework. In
the case of weak$^*$ Morita equivalence, this $W^*$-dilation is a $W^*$-module
over a von Neumann algebra generated by the non-selfadjoint dual operator
algebra. The theory of the $W^*$-dilation is a key part of the proof of our
main theorem.


title: Extended MQCD and SUSY/non-SUSY duality

abstract:
  We study the SUSY/non-SUSY duality proposed by Aganagic et al. from Type IIA
string and M-theory perspectives. We find that our brane configuration
generalizes the so-called $extended$ Seiberg-Witten theory on the one hand, and
provides a way to realize non-SUSY vacua by intersecting NS5-branes on the
other hand. We also argue how the partial SUSY breaking from $\Ncal=2$ down to
$\Ncal=1$ can be clearly visualized through the brane picture.


title: The axial anomaly and the phases of dense QCD

abstract:
  The QCD axial anomaly, by coupling the chiral condensate and BCS pairing
fields of quarks in dense matter, leads to a new critical point in the QCD
phase diagram \cite{HTYB,chiral2}, which at sufficiently low temperature should
terminate the line of phase transitions between chirally broken hadronic matter
and color superconducting quark matter. The critical point indicates that
matter at low temperature should cross over smoothly from the hadronic to the
quark phase, as suggested earlier on the basis of symmetry. We review here the
arguments, based on a general Ginzburg-Landau effective Lagrangian, for the
existence of the new critical point, as well as discuss possible connections
between the QCD phase structure and the BEC-BCS crossover in ultracold trapped
atomic fermion systems at unitarity. and implications for the presence of quark
matter in neutron stars.


title: Biased Range Trees

abstract:
  A data structure, called a biased range tree, is presented that preprocesses
a set S of n points in R^2 and a query distribution D for 2-sided orthogonal
range counting queries. The expected query time for this data structure, when
queries are drawn according to D, matches, to within a constant factor, that of
the optimal decision tree for S and D. The memory and preprocessing
requirements of the data structure are O(n log n).


title: The non-ballistic superluminal motion in the plane of the sky

abstract:
  Faster-than-light or superluminal motion was originally predicted as a
relativistic illusion of ballistic moving ejecta, and confirmed in a few tens
of sources observationally. However, the recent results of the long-term
multi-epoch observations of quasars, active galaxies, tracing the structure
further along the jets and following the motion of individual features for
longer time, rise questions that are difficult to understand by the standard
ballistic model. I.e., the ejecta are aligned with the local jet direction,
instead of the core; and within individual jets apparently inward-moving
features are observed. Here we show that these unexpected phenomena, although
only a small fraction among large samples, indicate the existence of
non-ballistic jet motion, in which a continuous jet produces a discrete hot
spot. And the precession of such a hot spot in the plane of the sky appears
superluminal. Therefore, an unified and simple interpretation to the new
results is obtained, which can be further tested through its predictions on the
evolution of ejecta. The study is of importance in the understanding of the
nature of superluminal motion, the interaction of jets and surrounding
materials, as well as the common physics underlying quasars and microquasars.


title: Improved parameters of the hydrogen-deficient binary star KSPer

abstract:
  Using the high resolution spectral observations obtained with the Nasmyth
Echelle Spectrograph NES of the 6m telescope we analysed the optical spectrum
of the hydrogen-deficient binary star KSPer. The atmospheric parameters derived
are: effective temperature Teff=9500+/-300 K, surface gravity log g=2.0+/-0.5,
and microturbulent velocity Vt=9.5+/-0.5km/s. The hydrogen deficiency is
H/He=3x10^{-5}, iron abundance is reduced by 0.8dex; nitrogen abundance is very
high [N/Fe]=1.4, but carbon and oxygen abundances are low. The star luminosity
is log L/Lo=3.3. A complex absorption and emission structure of the NaI D
doublet was revealed. We suggest that the emission component forms in the
circumbinary gaseous envelope.


title:
A distributed algorithm for computing and updating the process number of
  a forest

abstract:
  In this paper, we present a distributed algorithm to compute various
parameters of a tree such as the process number, the edge search number or the
node search number and so the pathwidth. This algorithm requires n steps, an
overall computation time of O(n log(n)), and n messages of size log_3(n)+3. We
then propose a distributed algorithm to update the process number (or the node
search number, or the edge search number) of each component of a forest after
adding or deleting an edge. This second algorithm requires O(D) steps, an
overall computation time of O(D log(n)), and O(D) messages of size log_3(n)+3,
where D is the diameter of the modified connected component. Finally, we show
how to extend our algorithms to trees and forests of unknown size using
messages of less than 2a+4+e bits, where a is the parameter to be determined
and e=1 for updates algorithms.


title:
Structural transition and anisotropic properties of single crystalline
  SrFe2As2

abstract:
  Plate-like single crystals of SrFe2As2 as large as 3x3x0.5 mm3 have been
grown out of Sn flux. The SrFe2As2 single crystals show a structural phase
transition from a high temperature tetragonal phase to a low temperature
orthorhombic phase at To = 198 K, and do not show any sign of superconductivity
down to 1.8 K. The structural transition is accompanied by an anomaly in the
electrical resistivity, Hall resistivity, specific heat, and the anisotropic
magnetic susceptibility. In an intermediate temperature range from 198 K to 160
K, single crystal X-ray diffraction suggests a coexistence of the
high-temperature tetragonal and the low-temperature orthorhombic phases.


title: Adaptation of the generic PDE's results to the notion of prevalence

abstract:
  Many generic results have been proved, especially concerning the qualitative
behaviour of solutions of partial differential equations. Recently, a new
notion of "almost always", the prevalence, has been developped for vectorial
spaces. This notion is interesting since, for example, prevalence sets are
equivalent to the full Lebesgue measure sets in finite dimensional spaces. The
purpose of this article is to adapt the generic PDE's results to the notion of
prevalence. In particular, we consider the cases where Sard-Smale theorems or
arguments of analytic perturbations of the parameters are used.


title:
Generic hyperbolicity of equilibria and periodic orbits of the parabolic
  equation on the circle

abstract:
  In this paper, we show that, for scalar reaction-diffusion equations on the
circle S1, the property of hyperbolicity of all equilibria and periodic orbits
is generic with respect to the non-linearity . In other words, we prove that in
an appropriate functional space of nonlinear terms in the equation, the set of
functions, for which all equilibria and periodic orbits are hyperbolic, is a
countable intersection of open dense sets. The main tools in the proof are the
property of the lap number and the Sard-Smale theorem.


title:
Microscopic approaches for nuclear Many-Body dynamics: applications to
  nuclear reactions

abstract:
  These lecture notes are addressed to PhD student and/or researchers who want
a general overview of microscopic approaches based on mean-field and applied to
nuclear dynamics. Our goal is to provide a good description of low energy
heavy-ion collisions. We present both formal aspects and practical applications
of the time-dependent Hartree-Fock (TDHF) theory. The TDHF approach gives a
mean field dynamics of the system under the assumption that particles evolve
independently in their self-consistent average field. As an example, we study
the fusion of both spherical and deformed nuclei with TDHF. We also focus on
nucleon transfer which may occur between nuclei below the barrier. These
studies allow us to specify the range of applications of TDHF in one hand, and,
on the other hand, its intrinsic limitations: absence of tunneling below the
Coulomb barrier, missing dissipative effects and/or quantum fluctuations.
Time-dependent mean-field theories should be improved to properly account for
these effects. Several approaches, generically named "beyond TDHF" are
presented which account for instance for pairing and/or direct nucleon-nucleon
collisions. Finally we discuss recent progresses in exact ab-initio methods
based on the stochastic mean-field concept.


title:
Superconducting transition detector in power amplification mode: a tool
  for cryogenic multiplexing

abstract:
  We demonstrate that substantial power gain can be obtained with
superconducting transition detectors. We describe the properties of the
detector as a power amplifier theoretically. In our first experiments power
gain of 23 was reached in a good agreement with the theory. The gain
facilitates noise matching of the readout circuit to the detectors in the case
of time division multiplexing.


title:
Quasi-Normal Modes of Massless Scalar Field around the 5D Ricci-flat
  Black String

abstract:
  As one candidate of the higher dimensional black holes, the 5D Ricci-flat
black string is considered in this paper. By means of a non-trivial potential
$V_{n}$, the quasi-normal modes of a massless scalar field around this black
string space is studied. By using the classical third order WKB approximation,
we analyse carefully the evolution of frequencies in two aspects, one is the
induced cosmological constant $\Lambda$ and the other is the quantum number
$n$. The massless scalar field decays more slowly because of the existences of
the fifth dimension and the induced cosmological constant. If extra dimension
has in fact existed near black hole, those quasi-normal frequencies may have
some indication on it.


title: Spatial separation effect of asteroids with different albedos

abstract:
  Numerical calculations of orbit evolutions of 1694 numbered asteroids
included in the IRAS catalogue, from 13.11.1996 to 06.03.2006 were carried out.
The values da - differences between the catalogue semimajor axes at 06.03.2006
and the calculated ones were computed. The average dependence da on albido p
shows decrease of da at increase of p, and it is significant. In other words,
semimajor axes of low-albedo asteroids are, on average, increasing as compared
with high-albedo ones. Speed of such possible spatial separation for very dim
and very bright asteroids of from 10 to 50km in order of magnitude is about 1
AU per 100 My. To explain this fact it may suppose an existence possibility of
a non-gravitational effect. Such supposition is confirmed by distributions p(a)
for asteroid families, above all, Flora family. An analysis of errors and
residuals in the used asteroid catalogues is evidence of such supposition.


title: Palm distributions of wave characteristics in encountering seas

abstract:
  Distributions of wave characteristics of ocean waves, such as wave slope,
waveheight or wavelength, are an important tool in a variety of oceanographic
applications such as safety of ocean structures or in the study of ship
stability, as will be the focus in this paper. We derive Palm distributions of
several wave characteristics that can be related to steepness of waves for two
different cases, namely for waves observed along a line at a fixed time point
and for waves encountering a ship sailing on the ocean. The relation between
the distributions obtained in the two cases is also given physical
interpretation in terms of a ``Doppler shift'' that is related to the velocity
of the ship and the velocities of the individual waves.


title: A property of C_p[0,1]

abstract:
  We prove that for every finite dimensional compact metric space $X$ there is
an open continuous linear surjection from $C_p[0,1]$ onto $C_p(X)$. The proof
makes use of embeddings introduced by Kolmogorov and Sternfeld in connection
with Hilbert's 13th problem.


title:
Realistic Earth matter effects and a method to acquire information about
  small \theta_{13} in the detection of supernova neutrinos

abstract:
  In this paper, we first calculate the realistic Earth matter effects in the
detection of type II supernova neutrinos at the Daya Bay reactor neutrino
experiment which is currently under construction. It is found that the Earth
matter effects depend on the neutrino incident angle $\theta$, the neutrino
mass hierarchy $\Delta m_{31}^{2}$, the crossing probability at the high
resonance region inside the supernova, $P_{H}$, the neutrino temperature,
$T_{\alpha}$, and the pinching parameter in the neutrino spectrum,
$\eta_{\alpha}$. We also take into account the collective effects due to
neutrino-neutrino interactions inside the supernova. With the expression for
the dependence of $P_H$ on the neutrino mixing angle $\theta_{13}$, we obtain
the relations between $\theta_{13}$ and the event numbers for various reaction
channels of supernova neutrinos. Using these relations, we propose a possible
method to acquire information about $\theta_{13}$ smaller than $1.5^\circ$.
Such a sensitivity cannot yet be achieved by the Daya Bay reactor neutrino
experiment which has a sensitivity of the order of $\theta_{13}\sim 3^\circ$.
Furthermore, we apply this method to other neutrino experiments, i.e. Super-K,
SNO, KamLAND, LVD, MinBooNE, Borexino, and Double-Chooz. We also study the
energy spectra of the differential event numbers, ${\rm d}N/{\rm d}E$.


title:
Cooperative oscillation of non-degenerate transverse modes in an optical
  system: multimode operation in parametric oscillators

abstract:
  We show experimentally that parametric interaction can induce a cooperative
oscillation of non simultaneously resonant transverse modes in an optical
parametric oscillator. More generally, this effect is expected to occur in any
spatially extended system subjected to boundary conditions where nonlinear wave
mixing of two nonresonant spatial modes can generate a resonant oscillation.


title: Star Formation in Various Environments

abstract:
  We describe studies of star formation in various galaxies using primarily
observations from the Wise Observatory. In addition to surface photometry in
the broad band UBVRI, we also use a set of narrow-band H-alpha filters tuned to
different redshifts to isolate the emission line. With these observational
data, and using models of evolutionary stellar populations, we unravel the star
formation histories of the galaxies and connect them to other parameters, such
as the galaxy environment.


title:
A Detection of Dark Matter Halo Ellipticity using Galaxy Cluster Lensing
  in SDSS

abstract:
  We measure the ellipticity of isolated clusters of galaxies in the Sloan
Digital Sky Survey (SDSS) using gravitational lensing. We stack the clusters,
rotating so that the major axes of the ellipses determined by the positions of
cluster member galaxies are aligned. We exclude the signal from the central 0.5
h^-1 Mpc to avoid problems with stacking alignment and cluster member
contamination. We fit an elliptical NFW profile and find an axis ratio for the
dark matter of f = b/a = 0.48+0.14-0.09 (1 sigma), and rule out f=1 at 99.6 per
cent confidence thus ruling out a spherical halo. We find that the ellipticity
of the cluster galaxy distribution is consistent with being equal to the dark
matter ellipticity. The results are similar if we change the isolation
criterion by 50 per cent in either direction.


title: Conditionally identically distributed species sampling sequences

abstract:
  Conditional identity in distribution (Berti et al. (2004)) is a new type of
dependence for random variables, which generalizes the well-known notion of
exchangeability. In this paper, a class of random sequences, called Generalized
Species Sampling Sequences, is defined and a condition to have conditional
identity in distribution is given. Moreover, a class of generalized species
sampling sequences that are conditionally identically distributed is introduced
and studied: the Generalized Ottawa sequences (GOS). This class contains a
'`randomly reinforced'' version of the P\'olya urn and of the
Blackwell-MacQueen urn scheme. For the empirical means and the predictive means
of a GOS, we prove two convergence results toward suitable mixtures of Gaussian
distributions. The first one is in the sense of stable convergence and the
second one in the sense of almost sure conditional convergence. In the last
part of the paper we study the length of the partition induced by a GOS at time
$n$, i.e. the random number of distinct values of a GOS until time $n$. Under
suitable conditions, we prove a strong law of large numbers and a central limit
theorem in the sense of stable convergence. All the given results in the paper
are accompanied by some examples.


title:
Self-similar solutions for the dynamical condensation of a radiative gas
  layer

abstract:
  A new self-similar solution describing the dynamical condensation of a
radiative gas is investigated under a plane-parallel geometry. The dynamical
condensation is caused by thermal instability. The solution is applicable to
generic flow with a net cooling rate per unit volume and time $\propto \rho^2
T^\alpha$, where $\rho$, $T$ and $\alpha$ are density, temperature and a free
parameter, respectively. Given $\alpha$, a family of self-similar solutions
with one parameter $\eta$ is found in which the central density and pressure
evolve as follows: $\rho(x=0,t)\propto (t_\mathrm{c}-t)^{-\eta/(2-\alpha)}$ and
$P(x=0,t)\propto (t_\mathrm{c}-t)^{(1-\eta)/(1-\alpha)}$, where $t_\mathrm{c}$
is an epoch when the central density becomes infinite. For $\eta\sim 0$, the
solution describes the isochoric mode, whereas for $\eta\sim1$, the solution
describes the isobaric mode. The self-similar solutions exist in the range
between the two limits; that is, for $0<\eta<1$. No self-similar solution is
found for $\alpha>1$. We compare the obtained self-similar solutions with the
results of one-dimensional hydrodynamical simulations. In a converging flow,
the results of the numerical simulations agree well with the self-similar
solutions in the high-density limit. Our self-similar solutions are applicable
to the formation of interstellar clouds (HI cloud and molecular cloud) by
thermal instability.


title: L2 Orthogonal Space Time Code for Continuous Phase Modulation

abstract:
  To combine the high power efficiency of Continuous Phase Modulation (CPM)
with either high spectral efficiency or enhanced performance in low Signal to
Noise conditions, some authors have proposed to introduce CPM in a MIMO frame,
by using Space Time Codes (STC). In this paper, we address the code design
problem of Space Time Block Codes combined with CPM and introduce a new design
criterion based on L2 orthogonality. This L2 orthogonality condition, with the
help of simplifying assumption, leads, in the 2x2 case, to a new family of
codes. These codes generalize the Wang and Xia code, which was based on
pointwise orthogonality. Simulations indicate that the new codes achieve full
diversity and a slightly better coding gain. Moreover, one of the codes can be
interpreted as two antennas fed by two conventional CPMs using the same data
but with different alphabet sets. Inspection of these alphabet sets lead also
to a simple explanation of the (small) spectrum broadening of Space Time Coded
CPM.


title: Ab Initio Phonon Dispersions for PbTe

abstract:
  We report first principles calculations of the phonon dispersions of PbTe
both for its observed structure and under compression. At the experimental
lattice parameter we find a near instability of the optic branch at the zone
center, in accord with experimental observations.This hardens quickly towards
the zone boundary. There is also a very strong volume dependence of this mode,
which is rapidly driven away from an instability by compression. These results
are discussed inrelation to the thermal conductivity of the material.


title:
Damping of Fast Magnetohydrodynamic Oscillations in Quiescent Filament
  Threads

abstract:
  High-resolution observations provide evidence about the existence of
small-amplitude transverse oscillations in solar filament fine structures.
These oscillations are believed to represent fast magnetohydrodynamic (MHD)
waves and the disturbances are seen to be damped in short timescales of the
order of 1 to 4 periods. In this Letter we propose that, due to the highly
inhomogeneous nature of the filament plasma at the fine structure spatial
scale, the phenomenon of resonant absorption is likely to operate in the
temporal attenuation of fast MHD oscillations. By considering transverse
inhomogeneity in a straight flux tube model we find that, for density
inhomogeneities typical of filament threads, the decay times are of a few
oscillatory periods only.


title:
Symbolic dynamics for the geodesic flow on locally symmetric orbifolds
  of rank one

abstract:
  We present a strategy for a geometric construction of cross sections for the
geodesic flow on locally symmetric orbifolds of rank one. We work it out in
detail for $\Gamma\backslash H$, where $H$ is the upper half plane and
$\Gamma=\PGamma_0(p)$, $p$ prime. Its associated discrete dynamical system
naturally induces a symbolic dynamics on $\R$. The transfer operator produced
from this symbolic dynamics has a particularly simple structure.


title: A Process Algebra Software Engineering Environment

abstract:
  In previous work we described how the process algebra based language PSF can
be used in software engineering, using the ToolBus, a coordination architecture
also based on process algebra, as implementation model. In this article we
summarize that work and describe the software development process more formally
by presenting the tools we use in this process in a CASE setting, leading to
the PSF-ToolBus software engineering environment. We generalize the refine step
in this environment towards a process algebra based software engineering
workbench of which several instances can be combined to form an environment.


title: ${L^p}$-variations for multifractal fractional random walks

abstract:
  A multifractal random walk (MRW) is defined by a Brownian motion subordinated
by a class of continuous multifractal random measures $M[0,t], 0\le t\le1$. In
this paper we obtain an extension of this process, referred to as multifractal
fractional random walk (MFRW), by considering the limit in distribution of a
sequence of conditionally Gaussian processes. These conditional processes are
defined as integrals with respect to fractional Brownian motion and convergence
is seen to hold under certain conditions relating the self-similarity (Hurst)
exponent of the fBm to the parameters defining the multifractal random measure
$M$. As a result, a larger class of models is obtained, whose fine scale
(scaling) structure is then analyzed in terms of the empirical structure
functions. Implications for the analysis and inference of multifractal
exponents from data, namely, confidence intervals, are also provided.


title: Open Letter to the OSA Topical Meeting "Slow and Fast Light"

abstract:
  The question is raised about whether the pulse delay in a saturable absorber
has anything to do with the "slow light" and group velocity reduction. We also
wonder why the 40-years-old trivial interpretation of the effect remains so far
ignored.


title: $^{26}$Al production from magnetically induced extramixing in AGB Stars

abstract:
  We discuss nucleosynthesis results obtained following the recent suggestion
that extramixing phenomena in red giants might be driven by magnetic buoyancy.
We explore for this model the production of the short-lived radioactive isotope
$^{26}$Al and of stable light nuclei, considering both the case of the general
buoyancy of flux tubes and that of the intermittent release of magnetized
unstable structures. We show that abundant $^{26}$Al can be produced, up to,
and above, the highest levels measured in presolar grains. This level would be
also sufficient to explain the early solar system $^{26}$Al as coming from a
nearby AGB star of low mass. The case of fast-moving instabilities is the most
efficient, reaching almost the same effectiveness as hot bottom burning (HBB).


title:
Magnetoconductance properties of rectangular arrays of spintronic
  quantum rings

abstract:
  Electron transport through multi-terminal rectangular arrays of quantum rings
is studied in the presence of Rashba-type spin-orbit interaction (SOI) and of a
perpendicular magnetic field. Using the analytic expressions for the
transmission and reflection coefficients for single rings we obtain the
conductance through such arrays as a function of the SOI strength, the magnetic
flux, and of the wave vector $k$ of the incident electron. Due to destructive
or constructive spin interferences caused by the SOI, the array can be totally
opaque for certain ranges of $k$, while there are parameter values where it is
completely transparent. Spin resolved transmission probabilities show
nontrivial spin transformations at the outputs of the arrays. When point-like
random scattering centers are placed between the rings, the Aharonov-Bohm peaks
split, and an oscillatory behavior of the conductance emerges as a function of
the SOI strength.


title: An overview of QML with a concrete implementation in Haskell

abstract:
  This paper gives an introduction to and overview of the functional quantum
programming language QML. The syntax of this language is defined and explained,
along with a new QML definition of the quantum teleport algorithm. The
categorical operational semantics of QML is also briefly introduced, in the
form of annotated quantum circuits. This definition leads to a denotational
semantics, given in terms of superoperators. Finally, an implementation in
Haskell of the semantics for QML is presented as a compiler. The compiler takes
QML programs as input, which are parsed into a Haskell datatype. The output
from the compiler is either a quantum circuit (operational), an isometry (pure
denotational) or a superoperator (impure denotational). Orthogonality
judgements and problems with coproducts in QML are also discussed.


title:
Looking for black-holes in X-ray binaries with XMM-Newton: XTE J1817-330
  and XTE J1856+053

abstract:
  The X-ray binary XTE J1817-330 was discovered in outburst on 26 January 2006
with RXTE/ASM. One year later, another X-ray transient discovered in 1996, XTE
J1856+053, was detected by RXTE during a new outburst on 28 February 2007. We
triggered XMM-Newton target of opportunity observations on these two objects to
constrain their parameters and search for a stellar black holes. We summarize
the properties of these two X-ray transients and show that the soft X-ray
spectra indicate indeed the presence of an accreting stellar black hole in each
of the two systems.


title: Quantum Turbulence

abstract:
  The present article reviews the recent developments in the physics of quantum
turbulence. Quantum turbulence (QT) was discovered in superfluid $^4$He in the
1950s, and the research has tended toward a new direction since the mid 90s.
The similarities and differences between quantum and classical turbulence have
become an important area of research. QT is comprised of quantized vortices
that are definite topological defects, being expected to yield a model of
turbulence that is much simpler than the classical model. The general
introduction of the issue and a brief review on classical turbulence are
followed by a description of the dynamics of quantized vortices. Then, we
discuss the energy spectrum of QT at very low temperatures. At low wavenumbers,
the energy is transferred through the Richardson cascade of quantized vortices,
and the spectrum obeys the Kolmogorov law, which is the most important
statistical law in turbulence; this classical region shows the similarity to
conventional turbulence. At higher wavenumbers, the energy is transferred by
the Kelvin-wave cascade on each vortex. This quantum regime depends strongly on
the nature of each quantized vortex. The possible dissipation mechanism is
discussed. Finally, important new experimental studies, which include
investigations into temperature-dependent transition to QT, dissipation at very
low temperatures, QT created by vibrating structures, and visualization of QT,
are reviewed. The present article concludes with a brief look at QT in atomic
Bose-Einstein condensates.


title:
Identification of information tonality based on Bayesian approach and
  neural networks

abstract:
  A model of the identification of information tonality, based on Bayesian
approach and neural networks was described. In the context of this paper
tonality means positive or negative tone of both the whole information and its
parts which are related to particular concepts. The method, its application is
presented in the paper, is based on statistic regularities connected with the
presence of definite lexemes in the texts. A distinctive feature of the method
is its simplicity and versatility. At present ideologically similar approaches
are widely used to control spam.


title:
Optimal block-tridiagonalization of matrices for coherent charge
  transport

abstract:
  Numerical quantum transport calculations are commonly based on a
tight-binding formulation. A wide class of quantum transport algorithms
requires the tight-binding Hamiltonian to be in the form of a block-tridiagonal
matrix. Here, we develop a matrix reordering algorithm based on graph
partitioning techniques that yields the optimal block-tridiagonal form for
quantum transport. The reordered Hamiltonian can lead to significant
performance gains in transport calculations, and allows to apply conventional
two-terminal algorithms to arbitrary complex geometries, including
multi-terminal structures. The block-tridiagonalization algorithm can thus be
the foundation for a generic quantum transport code, applicable to arbitrary
tight-binding systems. We demonstrate the power of this approach by applying
the block-tridiagonalization algorithm together with the recursive Green's
function algorithm to various examples of mesoscopic transport in
two-dimensional electron gases in semiconductors and graphene.


title:
Transverse Wave Propagation in Relativistic Two-fluid Plasmas in de
  Sitter Space

abstract:
  We investigate transverse electromagnetic waves propagating in a plasma in
the de Sitter space. Using the 3+1 formalism we derive the relativistic
two-fluid equations to take account of the effects due to the horizon and
describe the set of simultaneous linear equations for the perturbations. We use
a local approximation to investigate the one-dimensional radial propagation of
Alfv\'en and high frequency electromagnetic waves and solve the dispersion
relation for these waves numerically.


title:
In situ accurate determination of the zero time delay between two
  independent ultrashort laser pulses by observing the oscillation of an atomic
  excited wave packet

abstract:
  We propose a novel method that uses the oscillation of an atomic excited wave
packet observed through a pump-probe technique to accurately determine the zero
time delay between a pair of ultrashort laser pulses. This physically-based
approach provides an easy fix for the intractable problem of synchronizing two
different femtosecond laser pulses in a practical experimental environment,
especially where an in situ time zero measurement with high accuracy is
required.


title: Nonlinear switching of low-index defect modes in photonic lattices

abstract:
  We address nonlinear signal switching between two low-index defect channels
induced in periodic optical lattices. In contrast to conventional directional
couplers, where the guiding mechanism is total internal reflection or
refraction, in such Bragg-type coupler, the guidance is of a photonic-bandgap
origin. The coupling length in the low-index coupler is controlled by the
lattice parameters and by the channel spacing. In the nonlinear regime the
Bragg-type coupler behaves as an all-optical switch, exhibiting a remarkable
difference of switching power for focusing versus defocusing nonlinearity.


title:
Exact accelerating solitons in nonholonomic deformation of the KdV
  equation with two-fold integrable hierarchy

abstract:
  Recently proposed nonholonomic deformation of the KdV equation is solved
through inverse scattering method by constructing AKNS-type Lax pair. Exact and
explicit N-soliton solutions are found for the basic field and the deforming
function showing an unusual accelerated (decelerated) motion. A two-fold
integrable hierarchy is revealed, one with usual higher order dispersion and
the other with novel higher nonholonomic deformations.


title: Universal critical exponent in class D superconductors

abstract:
  We study a physical system consisting of non-interacting quasiparticles in
disordered superconductors that have neither time-reversal nor spin-rotation
invariance. This system belongs to class D within the recent classification
scheme of random matrix ensembles (RME) and its phase diagram contains three
different phases: metallic and two distinct localized phases with different
quantized thermal Hall conductances. We find that critical exponents describing
different transitions (insulator-to-insulator and insulator-to-metal) are
identical within the error of numerical calculations and also find that
critical disorder of the insulator-to-metal transition is energy independent.


title:
A mixed singular/switching control problem for a dividend policy with
  reversible technology investment

abstract:
  We consider a mixed stochastic control problem that arises in Mathematical
Finance literature with the study of interactions between dividend policy and
investment. This problem combines features of both optimal switching and
singular control. We prove that our mixed problem can be decoupled in two pure
optimal stopping and singular control problems. Furthermore, we describe the
form of the optimal strategy by means of viscosity solution techniques and
smooth-fit properties on the corresponding system of variational inequalities.
Our results are of a quasi-explicit nature. From a financial viewpoint, we
characterize situations where a firm manager decides optimally to postpone
dividend distribution in order to invest in a reversible growth opportunity
corresponding to a modern technology. In this paper a reversible opportunity
means that the firm may disinvest from the modern technology and return back to
its old technology by receiving some gain compensation. The results of our
analysis take qualitatively different forms depending on the parameters values.


title: Selective phase rotation quantum gate entangler

abstract:
  We construct a quantum gate entangler based on selective phase rotation
transform. In particular, we established a relation between quantum integral
transform and quantum gates entangler in terms of universal controlled gates
for multi-qubit states. Our construction is also related to the geometrical
structure of multipartite quantum systems.


title: Variance bounding Markov chains

abstract:
  We introduce a new property of Markov chains, called variance bounding. We
prove that, for reversible chains at least, variance bounding is weaker than,
but closely related to, geometric ergodicity. Furthermore, variance bounding is
equivalent to the existence of usual central limit theorems for all $L^2$
functionals. Also, variance bounding (unlike geometric ergodicity) is preserved
under the Peskun order. We close with some applications to Metropolis--Hastings
algorithms.


title: Robust model identification of actuated vortex wakes

abstract:
  We present a low-order modeling technique for actuated flows based on the
regularization of an inverse problem. The inverse problem aims at minimizing
the error between the model predictions and some reference simulations. The
parameters to be identified are a subset of the coefficients of a polynomial
expansion which models the temporal dynamics of a small number of global modes.
These global modes are found by Proper Orthogonal Decomposition, which is a
method to compute the most representative elements of an existing simulation
database in terms of energy. It is shown that low-order control models based on
a simple Galerkin projection and usual calibration techniques are not viable.
They are either ill-posed or they give a poor approximation of the solution as
soon as they are used to predict cases not belonging to the original solution
database. In contrast, numerical evidence shows that the method we propose is
robust with respect to variations of the control laws applied, thus allowing
the actual use of such models for control.


title: A Coherent View on Entropy

abstract:
  Informational entropy is often identified as physical entropy. This is
surprising because the two quantities are differently defined and furthermore
the former is a subjective quantity while the latter is an objective one. We
describe the problems and then present a possible view that reconciles the two
entropies. Informational entropy of a system is interpreted as physical entropy
of a whole composed of both the system and "memories" containing information
about the system.


title:
Perturbation-Assisted Laser-Induced Atomic Fragment Fluorescence
  Spectroscopy: A Facile Route to Spin-Forbidden States

abstract:
  This paper has been withdrawn by the authors, because the authors have made
abundant revisions and resubmitted the modified new version entitled
"Laser-induced atomic fragment fluorescence spectroscopy: A facile technique
for molecular spectroscopy of spin-forbidden states" to arXiv:0812.4554. Thanks
for your attention.


title:
Large Seebeck coefficients in Iron-oxypnictides : a new route towards
  n-type thermoelectric materials

abstract:
  The iron-oxypnictide compounds, recently reported as a new class of
superconductors when appropriately doped, exhibit large Seebeck coefficients,
of the order of -100 microV/K, while keeping good electrical conductivity.
Their power factor shows a peak at low temperatures, suggesting possible
applications of these materials in thermoelectric cooling modules in the liquid
nitrogen temperature range.


title:
Probability of primordial black hole formation and its dependence on the
  radial profile of initial configurations

abstract:
  In this paper we derive the probability of the radial profiles of spherically
symmetric inhomogeneities in order to provide an improved estimation of the
number density of primordial black holes (PBHs). We demonstrate that the
probability of PBH formation depends sensitively on the radial profile of the
initial configuration. We do this by characterising this profile with two
parameters chosen heuristically: the amplitude of the inhomogeneity and the
second radial derivative, both evaluated at the centre of the configuration. We
calculate the joint probability of initial cosmological inhomogeneities as a
function of these two parameters and then find a correspondence between these
parameters and those used in numerical computations of PBH formation. Finally,
we extend our heuristic study to evaluate the probability of PBH formation
taking into account for the first time the radial profile of curvature
inhomogeneities.


title: $EE_8$-lattices and dihedral groups

abstract:
  We classify integral rootless lattices which are sums of pairs of
$EE_8$-lattices (lattices isometric to $\sqrt 2$ times the $E_8$-lattice) and
which define dihedral groups of orders less than or equal to 12. Most of these
may be seen in the Leech lattice. Our classification may help understand
Miyamoto involutions on lattice type vertex operator algebras and give a
context for the dihedral groups which occur in the Glauberman-Norton moonshine
theory.


title:
Near-horizon limit of the charged BTZ black hole and AdS_2 quantum
  gravity

abstract:
  We show that the 3D charged Banados-Teitelboim-Zanelli (BTZ) black hole
solution interpolates between two different 2D AdS spacetimes: a near-extremal,
near-horizon AdS_2 geometry with constant dilaton and U(1) field and an
asymptotic AdS_2 geometry with a linear dilaton. Thus, the charged BTZ black
hole can be considered as interpolating between the two different formulations
proposed until now for AdS_2 quantum gravity. In both cases the theory is the
chiral half of a 2D CFT and describes, respectively, Brown-Hennaux-like
boundary deformations and near-horizon excitations. The central charge c_as of
the asymptotic CFT is determined by 3D Newton constant G and the AdS length l,
c_as=3l/G, whereas that of the near-horizon CFT also depends on the U(1) charge
Q, c_nh \propto l Q/\sqrt G.


title:
Backreaction of Cosmological Perturbations in Covariant Macroscopic
  Gravity

abstract:
  The problem of corrections to Einstein's equations arising from averaging of
inhomogeneities ("backreaction") in the cosmological context, has gained
considerable attention recently. We present results of analysing cosmological
perturbation theory in the framework of Zalaletdinov's fully covariant
Macroscopic Gravity. We show that this framework can be adapted to the setting
of cosmological perturbations in a manner which is free from gauge related
ambiguities. We derive expressions for the backreaction which can be readily
applied in \emph{any} situation (not necessarily restricted to the linear
perturbations considered here) where the \emph{metric} can be brought to the
perturbed FLRW form. In particular these expressions can be employed in toy
models studying nonlinear structure formation, and possibly also in N-body
simulations. Additionally, we present results of example calculations which
show that the backreaction remains negligible well into the matter dominated
era.


title: General Eigenvalue Correlations for the Real Ginibre Ensemble

abstract:
  We rederive in a simplified version the Lehmann-Sommers eigenvalue
distribution for the Gaussian ensemble of asymmetric real matrices, invariant
under real orthogonal transformations, as a basis for a detailed derivation of
a Pfaffian generating functional for $n$-point densities. This produces a
simple free-fermion diagram expansion for the correlations leading to
quaternion determinants in each order n. All will explicitly be given with the
help of a very simple symplectic kernel for even dimension $N$. The kernel is
valid both for complex and real eigenvalues and describes a deep connection
between both. A slight modification by an artificial additional Grassmannian
solves also the more complicated odd-$N$ case. As illustration we present some
numerical results in the space $\mathbb{C}^n$ of complex eigenvalue $n$-tuples.


title: A new form of three-body Faddeev equations in the continuum

abstract:
  We propose a novel approach to solve the three-nucleon (3N) Faddeev equation
which avoids the complicated singularity pattern going with the moving
logarithmic singularities of the standard approach. In this new approach the
treatment of the 3N Faddeev equation becomes essentially as simple as the
treatment of the two-body Lippmann-Schwinger equation. Very good agreement of
the new and old approaches in the application to nucleon-deuteron elastic
scattering and the breakup reaction is found.


title:
The relations among 8, 24, and 160 micron dust emission within nearby
  spiral galaxies

abstract:
  We investigate the relations among the stellar continuum-subtracted 8 micron
polycyclic aromatic hydrocarbon (PAH 8 micron) emission, 24 micron hot dust
emission, and 160 micron cold dust emission in fifteen nearby face-on spiral
galaxies in the Spitzer Infrared Nearby Galaxies Survey sample. The relation
between PAH 8 and 24 micron emission measured in ~2 kpc regions is found to
exhibit a significant amount of scatter, and strong spatial variations are
observed in the (PAH 8 micron)/24 micron surface brightness ratio. In
particular, the (PAH 8 micron)/24 micron surface brightness ratio is observed
to be high in the diffuse interstellar medium and low in bright star-forming
regions and other locations with high 24 micron surface brightness. PAH 8
micron emission is found to be well-correlated with 160 micron emission on
spatial scales of ~2 kpc, and the (PAH 8 micron)/160 micron surface brightness
ratio is generally observed to increase as the 160 micron surface brightness
increases. These results suggest that the PAHs are associated with the diffuse,
cold dust that produces most of the 160 micron emission in these galaxies, and
the variations in the (PAH 8 micron)/160 micron ratio may generally be
indicative of either the intensity or the spectrum of the interstellar
radiation field that is heating both the PAHs and the diffuse interstellar
dust.


title: Finitely summable Fredholm modules over higher rank groups and lattices

abstract:
  We give a complete classification (up to smooth homotopy) of finitely
summable Fredholm representations (Fredholm modules) over higher rank groups
and lattices. Our results are a direct consequence of work of Bader, Furman,
Gelander and Monod on generalisations of Kazhdan's property T for locally
compact groups.


title: L2 OSTC-CPM: Theory and design

abstract:
  The combination of space-time coding (STC) and continuous phase modulation
(CPM) is an attractive field of research because both STC and CPM bring many
advantages for wireless communications. Zhang and Fitz [1] were the first to
apply this idea by constructing a trellis based scheme. But for these codes the
decoding effort grows exponentially with the number of transmitting antennas.
This was circumvented by orthogonal codes introduced by Wang and Xia [2].
Unfortunately, based on Alamouti code [3], this design is restricted to two
antennas. However, by relaxing the orthogonality condition, we prove here that
it is possible to design L2-orthogonal space-time codes which achieve full rate
and full diversity with low decoding effort. In part one, we generalize the
two-antenna code proposed by Wang and Xia [2] from pointwise to
L2-orthogonality and in part two we present the first L2-orthogonal code for
CPM with three antennas. In this report, we detail these results and focus on
the properties of these codes. Of special interest is the optimization of the
bit error rate which depends on the initial phase of the system. Our simulation
results illustrate the systemic behavior of these conditions.


title: Stochastic Impulse Control of Non-Markovian Processes

abstract:
  We consider a class of stochastic impulse control problems of general
stochastic processes i.e. not necessarily Markovian. Under fairly general
conditions we establish existence of an optimal impulse control. We also prove
existence of combined optimal stochastic and impulse control of a fairly
general class of diffusions with random coefficients. Unlike, in the Markovian
framework, we cannot apply quasi-variational inequalities techniques. We rather
derive the main results using techniques involving reflected BSDEs and the
Snell envelope.


title:
Observation of Above-Threshold Dissociation of Na$_2^+$ in Intense Laser
  Fields

abstract:
  We report the observation of above-threshold dissociation of a multielectron
molecular system, Na$_2^+$. The process is due to continuum-continuum
transitions in a field-dressed molecular continuum. Three well resolved
fragmentation channels with different kinetic energy release patterns have been
detected, of which, two are associated with ordinary photodissociation via
light-induced potentials into Na(3s) + Na$^+$ and Na(3p) + Na$^+$, and one with
continuum-continuum transitions and above-threshold dissociation into Na(3p) +
Na$^+$. We show that when we dress this molecule with a field whose intensity
is ~3 x 10$^{12}$ W/cm$^2$, above-threshold dissociation prevails over other
processes, such as field-ionization followed by Coulomb explosion.


title: Substance graphs are optimal simple-graph representations of metabolism

abstract:
  One approach to studying the system-wide organization of biochemistry is to
use statistical graph theory. Even in such a heavily simplified method, which
disregards most of the dynamic aspects of biochemistry, one is faced with
fundamental questions, such as how the chemical reaction systems should be
reduced to a graph retaining as much functional information as possible from
the original reaction system. In such graph representations, should the edges
go between substrates and products, or substrates and substrates, or both?
Should vertices represent substances or reactions? Different definitions encode
different information about the reaction system. In this paper we evaluate four
different graph representations of metabolism, applied to data from different
organisms and databases. The graph representations are evaluated by comparing
the overlap between clusters (network modules) and annotated functions, and
also by comparing the set of identified currency metabolites with those that
other authors have identified using qualitative biological arguments. We find
that a "substance network," where all metabolites participating in a reaction
are connected, is relatively better than others, evaluated both with respect to
the functional overlap between modules and functions and to the number and
identity of identified currency metabolites.


title: Self-adjoint extensions of Coulomb systems in 1,2 and 3 dimensions

abstract:
  We study the nonrelativistic quantum Coulomb hamiltonian (i.e., inverse of
distance potential) in $R^n$, n = 1, 2, 3. We characterize their self-adjoint
extensions and, in the unidimensional case, present a discussion of
controversies in the literature, particularly the question of the permeability
of the origin. Potentials given by fundamental solutions of Laplace equation
are also briefly considered.


title: Local conservation laws of second-order evolution equations

abstract:
  Generalizing results by Bryant and Griffiths [Duke Math. J., 1995, V.78,
531-676], we completely describe local conservation laws of second-order
(1+1)-dimensional evolution equations up to contact equivalence. The possible
dimensions of spaces of conservation laws prove to be 0, 1, 2 and infinity. The
canonical forms of equations with respect to contact equivalence are found for
all nonzero dimensions of spaces of conservation laws.


title: Hydrogen adsorption on Pd(133) surface

abstract:
  In this study used is an approach based on measurements of the total energy
distribution (TED) of field emitted electrons in order to examine the
properties of Pd (133) from the aspect of both hydrogen adsorption and surface
hydrides formation. The most favourable sites offered to a hydrogen atom to be
adsorbed have been indicated and an attempt to describe the peaks of the
enhancement factor R spectrum to the specific adsorption sites has also been
made.


title: Notes on interacting holographic dark energy model in a closed universe

abstract:
  We consider interacting holographic dark energy model in Friedmann Robertson
Walker space time with positive spatial curvature and investigate the behavior
of curvature parameter and dark energy density in accelerated expanding epoch.
We also derive some conditions needed to cross the phantom divide line in this
model.


title:
Central limit theorem for signal-to-interference ratio of reduced rank
  linear receiver

abstract:
  Let $\mathbf{s}_k=\frac{1}{\sqrt{N}}(v_{1k},...,v_{Nk})^T,$ with
$\{v_{ik},i,k=1,...\}$ independent and identically distributed complex random
variables. Write $\mathbf{S}_k=(\mathbf{s}_1,...,\mathbf
{s}_{k-1},\mathbf{s}_{k+1},... ,\mathbf{s}_K),$ $\mathbf{P}_k=\operatorname
{diag}(p_1,...,p_{k-1},p_{k+1},...,p_K)$,
$\mathbf{R}_k=(\mathbf{S}_k\mathbf{P}_k\mathbf{S}_k^*+\sigma ^2\mathbf{I})$ and
$\mathbf{A}_{km}=[\mathbf{s}_k,\mathbf{R}_k\mathbf{s}_k,...
,\mathbf{R}_k^{m-1}\mathbf{s}_k]$. Define
$\beta_{km}=p_k\mathbf{s}_k^*\mathbf{A}_{km}(\mathbf {A}_{km}^*\times\
mathbf{R}_k\mathbf{A}_{km})^{-1}\mathbf{A}_{km}^*\mathbf{s}_k$, referred to as
the signal-to-interference ratio (SIR) of user $k$ under the multistage Wiener
(MSW) receiver in a wireless communication system. It is proved that the output
SIR under the MSW and the mutual information statistic under the matched filter
(MF) are both asymptotic Gaussian when $N/K\to c>0$. Moreover, we provide a
central limit theorem for linear spectral statistics of eigenvalues and
eigenvectors of sample covariance matrices, which is a supplement of Theorem 2
in Bai, Miao and Pan [Ann. Probab. 35 (2007) 1532--1572]. And we also improve
Theorem 1.1 in Bai and Silverstein [Ann. Probab. 32 (2004) 553--605].


title: Generalized Ardehali-Bell inequalities for graph states

abstract:
  We derive Bell inequalities for graph states by generalizing the approach
proposed by Ardehali [Phys. Rev. A 46, 5375 (1992)] for
Greenberger-Horne-Zeilinger (GHZ) states. Using this method, we demonstrate
that Bell inequalities with nonstabilizer observables are often superior to the
optimal GHZ-Mermin-type (or stabilizer-type) Bell inequalities.


title: Are Gamma-Ray Bursts a Standard Energy Reservoir?

abstract:
  One of the most important discoveries in the observation of gamma-ray bursts
(GRBs) is that the total energy emitted by a GRB in gamma-rays has a very
narrow distribution around 10^51 erg, which has led people to claim that GRBs
are standard energy explosions. As people made the claim they have ignored the
selection biases which must be important since GRB observations are strongly
fluence or flux-limited. In this paper we show that, when the selection effects
are considered, the intrinsic distribution of the GRB energy can be very broad.
The number of faint GRBs has been significantly underestimated because of the
fluence or flux limit. The bright part of the distribution has been affected by
another important selection effect arising from the beaming of GRB jets, which
is instrument-independent and caused by the fact that brighter GRBs tend to
have smaller jet angles and hence smaller probabilities to be detected. Our
finding indicates that GRBs are not a standard energy reservoir, and challenges
the proposal that GRBs can be used as standard candles to probe cosmology.


title: Stable length in stable groups

abstract:
  We show that the stable commutator length vanishes for certain groups defined
as infinite unions of smaller groups. The argument uses a group-theoretic
analogue of the Mazur swindle, and goes back to the works of Anderson, Fisher,
and Mather on homeomorphism groups.


title: Aberration and radiation pressure in the Klein and Poincare models

abstract:
  Aberration and radiation pressure reflected by a moving mirror are examples
of the Klein and Poincar\'e models of hyperbolic geometry, respectively.
Reflection at a moving mirror produces a two-way Dopper shift. Its one-way
counterpart, aberration, has nothing to do with the radiation pressure on a
moving mirror, but, rather with the pressure on a completely absorbing surface.
Both pressures vanish when the angle of parallelism is reached. Two-way,
second-order Doppler shifts can be used to establish experimentally the
existence of an angle of parallelism.


title:
Discovery of 17 new sharp-lined Ap stars with magnetically resolved
  lines

abstract:
  Chemically peculiar A stars (Ap) are extreme examples of the interaction of
atomic element diffusion processes with magnetic fields in stellar atmospheres.
The rapidly oscillating Ap stars provide a means for studying these processes
in 3D and are at the same time important for studying the pulsation excitation
mechanism in A stars. As part of the first comprehensive, uniform, high
resolution spectroscopic survey of Ap stars, which we are conducting in the
southern hemisphere with the Michigan Spectral Catalogues as the basis of
target selection, we report here the discovery of 17 new magnetic Ap stars
having spectroscopically resolved Zeeman components from which we derive
magnetic field moduli in the range 3 - 30 kG. Among these are 1) the current
second-strongest known magnetic A star, 2) a double-lined Ap binary with a
magnetic component and 3) an A star with particularly peculiar and variable
abundances. Polarimetry of these stars is needed to constrain their field
geometries and to determine their rotation periods. We have also obtained an
additional measurement of the magnetic field of the Ap star HD 92499.


title:
Coexistence of ferromagnetism and superconductivity: the role of kinetic
  interactions, kinetic correlations, and external pressure

abstract:
  We use the Hubbard type model to describe the coexistence between
superconductivity (SC) and ferromagnetism (F). Our Hamiltonian contains
single-site and two-site interactions. All inter-site interactions will have
included the inter-site kinetic correlation: $<c_{i\sigma}^{+}c_{j\sigma}>$,
within the Hartree-Fock approximation. To obtain the SC transition temperature
$T_{SC}$ and Curie temperature $T_{C}$ we use the Green's functions method. The
numerical results show that the singlet SC is eliminated by F, but the triplet
SC is either enhanced or depleted by F, depending on the carrier concentration
and direction of a superconducting spin pair with respect to magnetization. The
kinetic correlation is capable of creating superconductivity. We find that the
ferromagnetism created by change of the bandwidth can coexist with singlet
superconductivity. In the case of triplet superconductivity the ferromagnetism
creates different critical SC temperatures for the $A_{1}$ and $A_{2}$ phase
(the pair's spin parallel and antiparallel to magnetization, respectively).


title: Non-linear parent action and dual gravity

abstract:
  We give a reformulation of non-linear Einstein gravity, which contains the
dual graviton together with the ordinary metric and a shift gauge field. The
metric does not enter through a `kinetic' Einstein-Hilbert term, but via
topological couplings, and so the theory does not lead to a doubling of degrees
of freedom. The field equations take the form of first-order duality relations.
We analyze the gauge symmetries and comment on their meaning with regard to the
E11 proposal.


title:
Magnetic order in BaFe2As2, the parent compound of the FeAs based
  superconductors in a new structural family

abstract:
  In addition to higher Tc compared with the ubiquitous cuprates for a material
composed of a single electronically active layer, the newly discovered LnFeAsO
superconductors offer additional compositional variation. In a similar fashion
to the CuO2 layers in cuprates, the FeAs layers now dominate the electronic
states that produce superconductivity. Cuprate superconductors distinguish
themselves structurally by adopting different stacking of the Cu-O and
electronically inactive "spacer" layers. Using the same structural philosophy,
materials with the formula (A,K)Fe2As2,A=Ba or Sr have been reported and
possess a Tc~38 K. Here, we report the neutron diffraction studies of BaFe2As2
that shows, in contrast to previous studies on the LnFeAsO materials, an
antiferromagnetic transition which concurs with first-order structural
transition. Although the magnetic and structural transitions occur differently
in the AFe2As2 and LnFeAsO-type materials, this work clearly demonstrates that
the complete evolution to a low symmetry structure is a pre-requirement for the
magnetic order.


title:
High resolution radio study of the Pulsar Wind Nebula within the
  Supernova Remnant G0.9+0.1

abstract:
  We have conducted a radio study at 3.6, 6 and 20 cm using ATCA and VLA and
reprocessed XMM-Newton and Chandra data of the pulsar wind nebula (PWN) in the
supernova remnant (SNR) G0.9+0.1. The new observations revealed that the
morphology and symmetry suggested by Chandra observations (torus and jet-like
features) are basically preserved in the radio range in spite of the rich
structure observed in the radio emission of this PWN, including several arcs,
bright knots, extensions and filaments. The reprocessed X-ray images show for
the first time that the X-ray plasma fills almost the same volume as the radio
PWN. Notably the X-ray maximum does not coincide with the radio maximum and the
neutron star candidate CXOU J174722.8-280915 lies within a small depression in
the radio emission. From the new radio data we have refined the flux density
estimates, obtaining S(PWN) ~ 1.57 Jy, almost constant between 3.6 and 20 cm.
For the whole SNR (compact core and shell), a flux density S(at 20 cm)= 11.5 Jy
was estimated. Based on the new and the existing 90 cm flux density estimates,
we derived alpha(PWN)=-0.18+/-0.04 and alpha(shell)=-0.68+/- 0.07. From the
combination of the radio data with X-ray data, a spectral break is found near
nu ~ 2.4 x 10^(12) Hz. The total radio PWN luminosity is L(radio)=1.2 x 10^(35)
erg s^(-1) when a distance of 8.5 kpc is adopted. By assuming equipartition
between particle and magnetic energies, we estimate a nebular magnetic field B
= 56 muG. The associated particle energy turns out to be U(part)=5 x 10^(47)
erg and the magnetic energy U(mag)=2 x 10^(47) erg. Based on an empirical
relation between X-ray luminosity and pulsar energy loss rate, and the
comparison with the calculated total energy, a lower limit of 1100 yr is
derived for the age of this PWN.


title:
Crystal growth of copper-rich ytterbium compounds: The predicted giant
  unit cell structures YbCu4.4 and YbCu4.25

abstract:
  Two new phases YbCu4.4 and YbCu4.25 are found as a result of careful phase
diagram investigations. Between the congruent and peritectic formation of
YbCu4.5 and YbCu3.5, respectively, the phases YbCu4.4 and YbCu4.25 are formed
peritectically at 934(2)degC and 931(3)degC. Crystal growth was realised using
a Bridgman technique and single crystalline grains of about 50-100 10^{-6}m
were analyzed by electron diffraction and single crystal X-ray diffraction. Due
to the only slight differences in both compositions and formation temperatures
the growth of larger single crystals of a defined superstructure is
challenging. The compounds YbCu4.4 and YbCu4.25 fit in Cerny`s (J. Solid State
Chem. 174 (2003) 125) building principle {(RECu5)n(RECu2)} where RE = Yb with n
= 4 and 3. YbCu4.4 and YbCu4.25 base on AuBe5/MgCu2-type substructures and
contain approximately 4570 and 2780 atoms per unit cell. The new phases close
the gap in the series of known copper-rich rare earth compounds for n = 1, 2
(DyCu3.5, DyCu4.0) and n = 5 (YbCu4.5, DyCu4.5).


title: Regular Steinhaus graphs of odd degree

abstract:
  A Steinhaus matrix is a binary square matrix of size $n$ which is symmetric,
with diagonal of zeros, and whose upper-triangular coefficients satisfy
$a_{i,j}=a_{i-1,j-1}+a_{i-1,j}$ for all $2\leq i<j\leq n$. Steinhaus matrices
are determined by their first row. A Steinhaus graph is a simple graph whose
adjacency matrix is a Steinhaus matrix. We give a short new proof of a theorem,
due to Dymacek, which states that even Steinhaus graphs, i.e. those with all
vertex degrees even, have doubly-symmetric Steinhaus matrices. In 1979 Dymacek
conjectured that the complete graph on two vertices $K_2$ is the only regular
Steinhaus graph of odd degree. Using Dymacek's theorem, we prove that if
$(a_{i,j})_{1\leq i,j\leq n}$ is a Steinhaus matrix associated with a regular
Steinhaus graph of odd degree then its sub-matrix $(a_{i,j})_{2\leq i,j\leq
n-1}$ is a multi-symmetric matrix, that is a doubly-symmetric matrix where each
row of its upper-triangular part is a symmetric sequence. We prove that the
multi-symmetric Steinhaus matrices of size $n$ whose Steinhaus graphs are
regular modulo 4, i.e. where all vertex degrees are equal modulo 4, only depend
on $\lceil \frac{n}{24}\rceil$ parameters for all even numbers $n$, and on
$\lceil \frac{n}{30}\rceil$ parameters in the odd case. This result permits us
to verify the Dymacek's conjecture up to 1500 vertices in the odd case.


title: Stationary max-stable fields associated to negative definite functions

abstract:
  Let $W_i,i\in{\mathbb{N}}$, be independent copies of a zero-mean Gaussian
process $\{W(t),t\in{\mathbb{R}}^d\}$ with stationary increments and variance
$\sigma^2(t)$. Independently of $W_i$, let $\sum_{i=1}^{\infty}\delta_{U_i}$ be
a Poisson point process on the real line with intensity $e^{-y} dy$. We show
that the law of the random family of functions
$\{V_i(\cdot),i\in{\mathbb{N}}\}$, where $V_i(t)=U_i+W_i(t)-\sigma^2(t)/2$, is
translation invariant. In particular, the process
$\eta(t)=\bigvee_{i=1}^{\infty}V_i(t)$ is a stationary max-stable process with
standard Gumbel margins. The process $\eta$ arises as a limit of a suitably
normalized and rescaled pointwise maximum of $n$ i.i.d. stationary Gaussian
processes as $n\to\infty$ if and only if $W$ is a (nonisotropic) fractional
Brownian motion on ${\mathbb{R}}^d$. Under suitable conditions on $W$, the
process $\eta$ has a mixed moving maxima representation.


title:
Solutions to the Yang-Baxter equations with $osp_q(1|2)$ symmetry: Lax
  operators

abstract:
  We find a new $4\times4$ solution to the $osp_q(1|2)$-invariant Yang-Baxter
equation with simple dependence on the spectral parameter and propose $2\times
2$ matrix expressions for the corresponding Lax operator. The general
inhomogeneous universal spectral-parameter dependent $R$-matrix is derived. It
is proven, that there are two independent solutions to the homogeneous
$osp_q(1|2)$-invariant YBE, defined on the fundamental three dimensional
representations. One of them is the particular case of the universal matrix,
while the second one does not admit generalization to the higher dimensional
cases. Also the $3 \times 3$ matrix expression of the Lax operator is found,
which have a well defined limit at $q \to 1$.


title:
Another Correction. Error estimates for Binomial approximations of game
  options

abstract:
  The Annals of Applied Probability 16 (2006) 984--1033 [URL:
http://projecteuclid.org/euclid.aoap/1151592257]


title: Covariant Effective Action for Loop Quantum Cosmology a la Palatini

abstract:
  In loop quantum cosmology, non-perturbative quantum gravity effects lead to
the resolution of the big bang singularity by a quantum bounce without
introducing any new degrees of freedom. Though fundamentally discrete, the
theory admits a continuum description in terms of an effective Hamiltonian.
Here we provide an algorithm to obtain the corresponding effective action,
establishing in this way the covariance of the theory for the first time. This
result provides new insights on the continuum properties of the discrete
structure of quantum geometry and opens new avenues to extract physical
predictions such as those related to gauge invariant cosmological
perturbations.


title: Integrable theory of quantum transport in chaotic cavities

abstract:
  The problem of quantum transport in chaotic cavities with broken
time-reversal symmetry is shown to be completely integrable in the universal
limit. This observation is utilised to determine the cumulants and the
distribution function of conductance for a cavity with ideal leads supporting
an arbitrary number $n$ of propagating modes. Expressed in terms of solutions
to the fifth Painlev\'e transcendent and/or the Toda lattice equation, the
conductance distribution is further analysed in the large-$n$ limit that
reveals long exponential tails in the otherwise Gaussian curve.

categories: cond-mat.mes-hall hep-th math-ph math.MP nlin.CD nlin.SI


title:
Resonant low-energy electron scattering on short-range impurities in
  graphene

abstract:
  Resonant scattering of electrons with low energies (as compared to the
bandwidth) on a single neutral short-range impurity in graphene is analyzed
theoretically, taking into account the valley degeneracy. Resonances
dramatically increase the scattering cross-section and introduce a strong
energy dependence. Analysis of the tight-binding model shows that resonant
scattering is typical for generic impurities as long as they are sufficiently
strong (the potential is of the order of the electron bandwidth or higher).


title: Time-Resolved Measurement of a Charge Qubit

abstract:
  We propose a scheme for monitoring coherent quantum dynamics with good
time-resolution and low backaction, which relies on the response of the
considered quantum system to high-frequency ac driving. An approximate
analytical solution of the corresponding quantum master equation reveals that
the phase of an outgoing signal, which can directly be measured in an
experiment with lock-in technique, is proportional to the expectation value of
a particular system observable. This result is corroborated by the numerical
solution of the master equation for a charge qubit realized with a Cooper-pair
box, where we focus on monitoring coherent oscillations.


title: Sorting a Permutation by block moves

abstract:
  We prove a lower and an upper bound on the number of block moves necessary to
sort a permutation. We put our results in contrast with existing results on
sorting by block transpositions, and raise some open questions.


title: Free products, Orbit Equivalence and Measure Equivalence Rigidity

abstract:
  We study the analogue in orbit equivalence of free product decomposition and
free indecomposability for countable groups. We introduce the (orbit
equivalence invariant) notion of freely indecomposable ({\FI}) standard
probability measure preserving equivalence relations and establish a criterion
to check it, namely non-hyperfiniteness and vanishing of the first $L^2$-Betti
number. We obtain Bass-Serre rigidity results, \textit{i.e.} forms of
uniqueness in free product decompositions of equivalence relations with ({\FI})
components. The main features of our work are weak algebraic assumptions and no
ergodicity hypothesis for the components. We deduce, for instance, that a
measure equivalence between two free products of non-amenable groups with
vanishing first $\ell^2$-Betti numbers is induced by measure equivalences of
the components. We also deduce new classification results in Orbit Equivalence
and II$_1$ factors.


title: Chromogeometry and relativistic conics

abstract:
  This paper shows how a recent reformulation of the basics of classical
geometry and trigonometry reveals a three-fold symmetry between Euclidean and
non-Euclidean (relativistic) planar geometries. We apply this chromogeometry to
look at conics in a new light.


title:
Resonance Structure in the $\gamma\gamma$ Invariant Mass Spectrum in
  $p$C- and $d$C-Interactions

abstract:
  Along with $\pi^0$ and $\eta$ mesons, a resonance structure in the invariant
mass spectrum of two photons at $M_{\gamma\gamma}= 360 \pm 7 \pm 9$ MeV is
observed in the reaction $d C\to\gamma + \gamma +X$ at momentum 2.75 GeV/c per
nucleon. Estimates of its width and production cross section are $\Gamma = 63.7
\pm 17.8$ MeV and $\sigma_{\gamma\gamma}=98\pm24^{+93}_{-67} {\rm \mu b}$,
respectively. The collected statistics amount to $2339 \pm 340$ events of
$1.5\cdot 10^6$ triggered interactions of a total number $\sim 10^{12}$ of
$d$C-interactions. This resonance structure is not observed in $p$C collisions
at the beam momentum 5.5 GeV/c. Possible mechanisms of this ABC-like effect are
discussed.


title: SU(3)-Equivariant Quiver Gauge Theories and Nonabelian Vortices

abstract:
  We consider SU(3)-equivariant dimensional reduction of Yang-Mills theory on
Kaehler manifolds of the form M x SU(3)/H, with H = SU(2) x U(1) or H = U(1) x
U(1). The induced rank two quiver gauge theories on M are worked out in detail
for representations of H which descend from a generic irreducible
SU(3)-representation. The reduction of the Donaldson-Uhlenbeck-Yau equations on
these spaces induces nonabelian quiver vortex equations on M, which we write
down explicitly. When M is a noncommutative deformation of the space C^d, we
construct explicit BPS and non-BPS solutions of finite energy for all cases. We
compute their topological charges in three different ways and propose a novel
interpretation of the configurations as states of D-branes. Our methods and
results generalize from SU(3) to any compact Lie group.


title: Electronic structure of multilayer graphene

abstract:
  We study the electronic structure of multilayer graphene using a
$\pi$-orbital continuum model with nearest-neighbor intralayer and interlayer
tunneling. Using degenerate state perturbation theory, we show that the
low-energy electronic structure of arbitrarily stacked graphene multilayers
consists of chiral pseudospin doublets with a conserved chirality sum.


title: Tau Physics: Theory Overview

abstract:
  The present status of some selected topics on tau physics is presented:
charged-current universality tests, bounds on lepton-flavour violation, the
determination of alpha_s from the inclusive tau hadronic width, the measurement
of |V_{us}| through the Cabibbo-suppressed decays of the tau, and the
theoretical description of the "tau -> nu_tau K pi" spectrum.


title: Astrophysical Sources of Stochastic Gravitational-Wave Background

abstract:
  We review the spectral properties of stochastic backgrounds of astrophysical
origin and discuss how they may differ from the primordial contribution by
their statistical properties. We show that stochastic searches with the next
generation of terrestrial interferometers could put interesting constrains on
the physical properties of astrophysical populations, such as the ellipticity
and magnetic field of magnetars, or the coalescence rate of compact binaries.


title: Jupiter - friend or foe? I: the asteroids

abstract:
  The asteroids are the major source of potential impactors on the Earth today.
It has long been assumed that the giant planet Jupiter acts as a shield,
significantly lowering the impact rate on the Earth from both cometary and
asteroidal bodies. Such shielding, it is claimed, enabled the development and
evolution of life in a collisional environment which is not overly hostile. The
reduced frequency of impacts, and of related mass extinctions, would have
allowed life the time to thrive, where it would otherwise have been suppressed.
However, in the past, little work has been carried out to examine the validity
of this idea. In the first of several papers, we examine the degree to which
the impact risk resulting from a population representative of the asteroids is
enhanced or lessened by the presence of a giant planet, in an attempt to fully
understand the impact regime under which life on Earth has developed. Our
results show that the situation is far less clear cut that has previously been
assumed - for example, the presence of a giant planet can act to enhance the
impact rate of asteroids on the Earth significantly.


title: Report IAU Comm. 42, Close Binary Stars

abstract:
  Brief summaries are given about (1) close binary research from the
perspective of the Bibliography of Close Binaries, (2) low-mass binaries and
model discrepancies, (3) W UMa-type binaries, (4) cataclysmic variables, (5)
Algol binaries, (6) the oEA stars, (7) effects of binarity on stellar activity.


title: Polynomial least squares fitting in the Bernstein basis

abstract:
  The problem of polynomial regression in which the usual monomial basis is
replaced by the Bernstein basis is considered. The coefficient matrix A of the
overdetermined system to be solved in the least squares sense is then a
rectangular Bernstein-Vandermonde matrix. In order to use the method based on
the QR decomposition of A, the first stage consists of computing the bidiagonal
decomposition of the coefficient matrix A. Starting from that bidiagonal
decomposition, an algorithm for obtaining the QR decomposition of A is the
applied. Finally, a triangular system is solved by using the bidiagonal
decomposition of the R-factor of A. Some numerical experiments showing the
behavior of this approach are included.


title: Chaotic inflation, radiative corrections and precision cosmology

abstract:
  We employ chaotic (phi^2 and phi^4) inflation to illustrate the important
role radiative corrections can play during the inflationary phase. Yukawa
interactions of phi, in particular, lead to corrections of the form -kappa
phi^4 ln(phi/mu), where kappa>0 and mu is a renormalization scale. For
instance, phi^4 chaotic inflation with radiative corrections looks compatible
with the most recent WMAP (5 year) analysis, in sharp contrast to the tree
level case. We obtain the 95% confidence limits 2.4x10^-14<~kappa<~5.7x10^-14,
0.931<~n_s<~0.958 and 0.038<~r<~0.205, where n_s and r respectively denote the
scalar spectral index and scalar to tensor ratio. The limits for phi^2
inflation are kappa<~7.7x10^-15, 0.929<~n_s<~0.966 and 0.023<~r<~0.135. The
next round of precision experiments should provide a more stringent test of
realistic chaotic phi^2 and phi^4 inflation.


title: Crossover from Attractive to Repulsive Casimir Forces and Vice Versa

abstract:
  Systems described by an O(n) symmetrical $\phi^4$ Hamiltonian are considered
in a $d$-dimensional film geometry at their bulk critical points. The critical
Casimir forces between the film's boundary planes $\mathfrak{B}_j, j=1,2$, are
investigated as functions of film thickness $L$ for generic symmetry-preserving
boundary conditions $\partial_n\bm{\phi}=\mathring{c}_j\bm{\phi}$. The
$L$-dependent part of the reduced excess free energy per cross-sectional area
takes the scaling form $f_{\text{res}}\approx
D(c_1L^{\Phi/\nu},c_2L^{\Phi/\nu})/L^{d-1}$ when $d<4$, where $c_i$ are scaling
fields associated with the variables $\mathring{c}_i$, and $\Phi$ is a surface
crossover exponent. Explicit two-loop renormalization group results for the
function $D(\mathsf{c}_1,\mathsf{c}_2)$ at $d=4-\epsilon$ dimensions are
presented. These show that (i) the Casimir force can have either sign,
depending on $\mathsf{c}_1$ and $\mathsf{c}_2$, and (ii) for appropriate
choices of the enhancements $\mathring{c}_j$, crossovers from attraction to
repulsion and vice versa occur as $L$ increases.


title: Superconductivity in Silicon Nanostructures

abstract:
  We present the findings of the superconductivity in the silicon
nanostructures prepared by short time diffusion of boron after preliminary
oxidation of the n-type Si (100) surface. These Si-based nanostructures
represent the p-type high mobility silicon quantum well (Si-QW) confined by the
delta - barriers heavily doped with boron. The ESR studies show that the delta
- barriers appear to consist of the trigonal dipole centers, B(+)-B(-), which
are caused by the negative-U reconstruction of the shallow boron acceptors,
2B(0)=>B(+)-B(-). The temperature and magnetic field dependencies of the
resistance, thermo-emf, specific heat and magnetic susceptibility demonstrate
that the high temperature superconductivity observed seems to result from the
transfer of the small hole bipolarons through these negative-U dipole centers
of boron at the Si-QW - delta - barrier interfaces. The value of the
superconductor energy gap obtained is in a good agreement with the data derived
from the oscillations of the conductance in normal state and of the
zero-resistance supercurrent in superconductor state as a function of the bias
voltage. These oscillations appear to be correlated by on- and off-resonance
tuning the two-dimensional subbands of holes with the Fermi energy in the
superconductor delta - barriers. Finally, the proximity effect in the S- Si-QW
-S structure is revealed by the findings of the multiple Andreev reflection
(MAR) processes and the quantization of the supercurrent.


title:
A Spectroscopic Survey of WNL Stars in the LMC: General Properties and
  Binary Status

abstract:
  We report the results of an intense, spectroscopic survey of all 41
late-type, nitrogen-rich Wolf-Rayet (WR) stars in the Large Magellanic Cloud
(LMC) observable with ground-based telescopes. This survey concludes the
decade-long effort of the Montr\'eal Massive Star Group to monitor every known
WR star in the Magellanic Clouds except for the 6 crowded WNL stars in R136,
which will be discussed elsewhere. The focus of our survey was to monitor the
so-called WNL stars for radial-velocity (RV) variability in order to identify
the short- to intermediate-period ($P \la 200$ days) binaries among them. Our
results are in line with results of previous studies of other WR subtypes, and
show that the binary frequency among LMC WNL stars is statistically consistent
with that of WNL stars in the Milky Way. We have identified four previously
unknown binaries, bringing the total number of known WNL binaries in the LMC to
nine. Since it is very likely that none but one of the binaries are classical,
helium-burning WNL stars, but rather superluminous, hence extremely massive,
hydrogen-burning objects, our study has dramatically increased the number of
known binaries harbouring such objects, and thus paved the way to determine
their masses through model-independent, Keplerian orbits. It is expected that
some of the stars in our binaries will be among the most massive known. With
the binary status of each WR star now known, we also studied the photometric
and X-ray properties of our program stars using archival MACHO photometry as
well as Chandra and ROSAT data. We find that one of our presumably single WNL
stars is among the X-ray brightest WR sources known. We also identify a binary
candidate from its RV variability and X-ray luminosity which harbours the most
luminous WR star known in the Local Group.


title: A logic with temporally accessible iteration

abstract:
  Deficiency in expressive power of the first-order logic has led to developing
its numerous extensions by fixed point operators, such as Least Fixed-Point
(LFP), inflationary fixed-point (IFP), partial fixed-point (PFP), etc. These
logics have been extensively studied in finite model theory, database theory,
descriptive complexity. In this paper we introduce unifying framework, the
logic with iteration operator, in which iteration steps may be accessed by
temporal logic formulae. We show that proposed logic FO+TAI subsumes all
mentioned fixed point extensions as well as many other fixed point logics as
natural fragments. On the other hand we show that over finite structures FO+TAI
is no more expressive than FO+PFP. Further we show that adding the same
machinery to the logic of monotone inductions (FO+LFP) does not increase its
expressive power either.


title:
System size, energy, centrality and pseudorapidity dependence of
  charged-particle density in Au+Au and Cu+Cu collisions at RHIC

abstract:
  Charged particle pseudorapidity distributions are presented from the PHOBOS
experiment at RHIC, measured in Au+Au and Cu+Cu collisions at sqrt{s_NN}=19.6,
22.4, 62.4, 130 and 200 GeV, as a function of collision centrality. The
presentation includes the recently analyzed Cu+Cu data at 22.4 GeV. The
measurements were made by the same detector setup over a broad range in
pseudorapidity, |eta|<5.4, allowing for a reliable systematic study of particle
production as a function of energy, centrality and system size. Comparing Cu+Cu
and Au+Au results, we find that the total number of produced charged particles
and the overall shape (height and width) of the pseudorapidity distributions
are determined by the number of nucleon participants, N_part. Detailed
comparisons reveal that the matching of the shape of the Cu+Cu and Au+Au
pseudorapidity distributions over the full range of eta is better for the same
N_part/2A value than for the same N_part value, where A denotes the mass
number. In other words, it is the geometry of the nuclear overlap zone, rather
than just the number of nucleon participants that drives the detailed shape of
the pseudorapidity distribution and its centrality dependence.


title: Statistical Ensembles with Volume Fluctuations

abstract:
  The volume fluctuations in statistical mechanics are discussed. First, the
volume fluctuations in ensembles with a fixed external pressure, the so called
pressure ensembles, are considered. Second, a generalization of the pressure
ensembles is suggested. Namely, the statistical ensembles with the volume
fluctuating according to externally given distributions are considered. Several
examples and possible applications in statistical models of hadron production
are discussed.


title: Dynamic vacuum variable and equilibrium approach in cosmology

abstract:
  A modified-gravity theory is considered with a four-form field strength F, a
variable gravitational coupling parameter G(F), and a standard matter action.
This theory provides a concrete realization of the general vacuum variable q as
the four-form amplitude F and allows for a study of its dynamics. The theory
gives a flat Friedmann-Robertson-Walker universe with rapid oscillations of the
effective vacuum energy density (cosmological "constant"), whose amplitude
drops to zero asymptotically. Extrapolating to the present age of the Universe,
the order of magnitude of the average vacuum energy density agrees with the
observed near-critical vacuum energy density of the present universe. It may
even be that this type of oscillating vacuum energy density constitutes a
significant part of the so-called cold dark matter in the standard
Friedmann-Robertson-Walker framework.


title:
Biaxial nematic and smectic phases of parallel particles with different
  cross sections

abstract:
  We have calculated the phase diagrams of one--component fluids made of five
types of biaxial particles differing in their cross sections. The orientation
of the principal particle axis is fixed in space, while the second axis is
allowed to freely rotate. We have constructed a free-energy density functional
based on fundamental--measure theory to study the relative stability of nematic
and smectic phases with uniaxial, biaxial and tetratic symmetries. Minimization
of the density functional allows us to study the phase behavior of the biaxial
particles as a function of the cross-section geometry. For low values of the
aspect ratio of the particle cross section, we obtain smectic phases with
tetratic symmetry, although metastable with respect to the crystal, as our MC
simulation study indicates. For large particle aspect ratios and in analogy
with previous work [Phys. Chem. Chem. Phys. 5, 3700 (2003)], we have found a
four--phase point where four spinodals, corresponding to phase transitions
between phases with different symmetries, meet together. The location of this
point is quite sensitive to particle cross section, which suggests that
optimizing the particle geometry could be a useful criterion in the design of
colloidal particles that can exhibit an increased stability of the biaxial
nematic phase with respect to other competing phases with spatial order.


title: Axions and the cooling of white dwarf stars

abstract:
  White dwarfs are the end-product of the lifes of intermediate- and low-mass
stars and their evolution is described as a simple cooling process. Recently,
it has been possible to determine with an unprecedented precision their
luminosity function, that is, the number of stars per unit volume and
luminosity interval. We show here that the shape of the bright branch of this
function is only sensitive to the averaged cooling rate of white dwarfs and we
propose to use this property to check the possible existence of axions, a
proposed but not yet detected weakly interacting particle. Our results indicate
that the inclusion of the emission of axions in the evolutionary models of
white dwarfs noticeably improves the agreement between the theoretical
calculations and the observational white dwarf luminosity function. The best
fit is obtained for m_a cos^2 \beta ~ 5 meV, where m_a is the mass of the axion
and cos^2 \beta is a free parameter. We also show that values larger than 10
meV are clearly excluded. The existing theoretical and observational
uncertainties do not allow yet to confirm the existence of axions, but our
results clearly show that if their mass is of the order of few meV, the white
dwarf luminosity function is sensitive enough to detect their existence.


title: A tight closure approach to a result of G. Faltings

abstract:
  Using a result of M. Hochster and C. Huneke on $F$-rational rings a criterion
for complete intersection rings of characteristic $p>0$ is presented. As an
application, we give a completely different proof for an algebraic result of G.
Faltings that was used by Taylor and Wiles in \cite{TW} for a simplification of
the proof of the minimal deformation problem.


title:
Phase diagram and complexity of mode-locked lasers: from order to
  disorder

abstract:
  We investigate mode-locking processes in lasers displaying a variable degree
of structural randomness, from standard optical cavities to multiple-scattering
media. By employing methods mutuated from spin-glass theory, we analyze the
mean-field Hamiltonian and derive a phase-diagram in terms of the pumping rate
and the degree of disorder. Three phases are found: i) paramagnetic,
corresponding to a noisy continuous wave emission, ii) ferromagnetic, that
describes the standard passive mode-locking, and iii) the spin-glass in which
the phases of the electromagnetic field are frozen in a exponentially large
number of configurations. The way the mode-locking threshold is affected by the
amount of disorder is quantified. The results are also relevant for other
physical systems displaying a random Hamiltonian, like Bose-Einstein
condensates and nonlinear optical beams.