title:
Gevrey regularity of the global attractor of the 3D Navier-Stokes-Voight
  equations

abstract:
  Recently, the Navier-Stokes-Voight (NSV) model of viscoelastic incompressible
fluid has been proposed as a regularization of the 3D Navier-Stokes equations
for the purpose of direct numerical simulations. In this work we prove that the
global attractor of the $D NSV equations, driven by an analytic forcing,
consists of analytic functions. A consequence of this result is that the
spectrum of the solutions of the 3D NSV system, lying on the global attractor,
have exponentially decaying tail, despite the fact that the equations behave
like a damped hyperbolic system, rather than the parabolic one. This result
provides an additional evidence that the 3D NSV with the small regularization
parameter enjoys similar statistical properties as the 3D Navier-Stokes
equations. Finally, we calculate a lower bound for the exponential decaying
scale -- the scale at which the spectrum of the solution start to decay
exponentially, and establish a similar bound for the steady state solutions of
the 3D NSV and 3D Navier-Stokes equations. Our estimate coincides with similar
available lower bound for the smallest dissipation length scale of solutions of
the 3D Navier-Stokes equations.


title: Steady-state, effective-temperature dynamics in a glassy material

abstract:
  We present an STZ-based analysis of numerical simulations by Haxton and Liu
(HL). The extensive HL data sharply test the basic assumptions of the STZ
theory, especially the central role played by the effective disorder
temperature as a dynamical state variable. We find that the theory survives
these tests, and that the HL data provide important and interesting constraints
on some of its specific ingredients. Our most surprising conclusion is that,
when driven at various constant shear rates in the low-temperature glassy
state, the HL system exhibits a classic glass transition, including
super-Arrhenius behavior, as a function of the effective temperature.


title: Photometric Redshifts and Photometry Errors

abstract:
  We examine the impact of non-Gaussian photometry errors on photometric
redshift performance. We find that they greatly increase the scatter, but this
can be mitigated to some extent by incorporating the correct noise model into
the photometric redshift estimation process. However, the remaining scatter is
still equivalent to that of a much shallower survey with Gaussian photometry
errors. We also estimate the impact of non-Gaussian errors on the spectroscopic
sample size required to verify the photometric redshift rms scatter to a given
precision. Even with Gaussian {\it photometry} errors, photometric redshift
errors are sufficiently non-Gaussian to require an order of magnitude larger
sample than simple Gaussian statistics would indicate. The requirements
increase from this baseline if non-Gaussian photometry errors are included.
Again the impact can be mitigated by incorporating the correct noise model, but
only to the equivalent of a survey with much larger Gaussian photometry errors.
However, these requirements may well be overestimates because they are based on
a need to know the rms, which is particularly sensitive to tails. Other
parametrizations of the distribution may require smaller samples.


title: Parallel TREE code for two-component ultracold plasma analysis

abstract:
  The TREE method has been widely used for long-range interaction {\it N}-body
problems. We have developed a parallel TREE code for two-component classical
plasmas with open boundary conditions and highly non-uniform charge
distributions. The program efficiently handles millions of particles evolved
over long relaxation times requiring millions of time steps. Appropriate domain
decomposition and dynamic data management were employed, and large-scale
parallel processing was achieved using an intermediate level of granularity of
domain decomposition and ghost TREE communication. Even though the
computational load is not fully distributed in fine grains, high parallel
efficiency was achieved for ultracold plasma systems of charged particles. As
an application, we performed simulations of an ultracold neutral plasma with a
half million particles and a half million time steps. For the long temporal
trajectories of relaxation between heavy ions and light electrons, large
configurations of ultracold plasmas can now be investigated, which was not
possible in past studies.


title:
Probing the Efficiency of Electron-Proton Coupling in Relativistic
  Collisionless Shocks through the Radio Polarimetry of Gamma-Ray Burst
  Afterglows

abstract:
  The late-time optical/radio afterglows of $\gamma$-ray bursts (GRBs) are
believed to be synchrotron emission of electrons accelerated in relativistic
collisionless shocks propagating in the ambient medium of the sources. However,
the fraction $f$ of electrons that are coupled to protons and accelerated
remains unclear and a large number of thermal electrons that are not coupled to
protons may be left behind. If $f<1$, the true explosion energies of GRBs are
$f^{-1}$ times larger than those commonly estimated with $f=1$. Thus the value
of $f$ gives an important constraint on the nature of the central engine of
GRBs and the physics of collisionless shocks. Although early-time radio
observations can probe the thermal electrons, they are difficult at present. We
show that the Faraday rotation effects of the thermal electrons may suppress
the linear polarization of the afterglow at frequencies higher than the
absorption frequency in the late time, if the magnetic field is ordered at
least in parts, and that $f$ can be constrained through the observation of the
effects. We find that those effects may be detected with late-time, > 1 day,
polarimetry with ALMA for a burst occurring within 1 Gpc (i.e., z ~ 0.2), if $f
\sim 10^{-1}$.


title: Viscosity of Earth's Outer Core

abstract:
  A viscosity profile across the entire fluid outer core is found by
interpolating between measured boundary values, using a differential form of
the Arrhenius law governing pressure and temperature dependence. The discovery
that both the retrograde and prograde free core nutations are in free decay
(Palmer and Smylie, 2005) allows direct measures of viscosity at the top of the
outer core, while the reduction in the rotational splitting of the two
equatorial translational modes of the inner core allows it to be measured at
the bottom. We find 2,371 plus/minus 1,530 Pa.s at the top and 1.247 plus/minus
0.035 x 10^11 Pa.s at the bottom. Following Brazhkin (1998) and Brazhkin and
Lyapin (2000) who get 10^2 Pa.s at the top, 10^11 Pa.s at the bottom, by an
Arrhenius extrapolation of laboratory experiments, we use a differential form
of the Arrhenius law to interpolate along the melting temperature curve to find
a viscosity profile across the outer core. We find the variation to be closely
log-linear between the measured boundary values. The close agreement of the
boundary values of viscosity, found by Arrhenius extrapolation of laboratory
experiments, with those found from the free core nutations, and the inner core
translational modes, suggests that core flows are laminar and that the returned
viscosities are measures of their molecular values. This would not be the case
in the presence of the vigorous turbulent convection sometimes postulated by
dynamo theorists. The local Ekman number is found to range from 10^-2 at the
bottom of the outer core to 10^-10 at the top. Except in the very lower part of
the outer core, Ekman numbers are in the range 10^-4 to 10^-5, or below, in
which the laminar flows of numerical dynamos and laboratory rotating fluids
experiments occur.


title: Mistake Analyses on Proof about Perfect Secrecy of One-time-pad

abstract: This paper has been withdrawn


title:
The quest for three-color entanglement: experimental investigation of
  new multipartite quantum correlations

abstract:
  We experimentally investigate quadrature correlations between pump, signal,
and idler fields in an above-threshold optical parametric oscillator. We
observe new quantum correlations among the pump and signal or idler beams, as
well as among the pump and a combined quadrature of signal and idler beams. A
further investigation of unforeseen classical noise observed in this system is
presented, which hinders the observation of the recently predicted tripartite
entanglement. In spite of this noise, current results approach the limit
required to demonstrate three-color entanglement.


title: The Variable Warm Absorber in Circinus X-1

abstract:
  We observed Circinus X-1 twice during a newly reached low-flux phase near
zero orbital phase using the High-Energy Transmission Grating Spectrometer
(HETGS) onboard Chandra. In both observations the source did not show the P
Cygni lines we observed during the high-flux phases of the source in 2000 and
2001. During pre-zero phase the source did not exhibit significant variability
and exhibited an emission-line spectrum rich in H- and He-like lines from high
Z elements such as Si, S, Ar, and Ca. We analyzed all high resolution X-ray
spectra by fitting photoionization and absorption models from the most recent
version of the XSTAR code. The pre-zero phase spectrum could be fully modeled
with a very hot photoionized plasma with an ionization parameter of log xi =
3.0. Post-zero phase episodes feature absorbers with variable high columns,
ionization parameter, and luminosity. While cold absorption remains at levels
quite similar to the one observed in previous years, the new observations show
unprecedented levels of variable warm absorption. The line emissivities also
indicate that the observed low source luminosity is inconsistent with a static
hot accretion disk corona (ADC), an effect that seems common to other near
edge-on ADC sources as well. We conclude that unless there exists some means of
coronal heating other than X-rays, the true source luminosity is likely much
higher and we observe obscuration in analogy to the extragalactic Seyfert II
sources. We discuss possible consequences and relate cold, luke-warm, warm, and
hot absorbers to dynamic accretion scenarios.


title: Polynomial Fusion Rings of Logarithmic Minimal Models

abstract:
  We identify quotient polynomial rings isomorphic to the recently found
fundamental fusion algebras of logarithmic minimal models.


title: The Classification of Higher Order Modular Forms and their Cohomology

abstract:
  We construct bases for the spaces of higher order modular forms of all orders
and weights. We also provide a cohomological interpretation of these forms.


title: On posterior distribution of Bayesian wavelet thresholding

abstract:
  We investigate the posterior rate of convergence for wavelet shrinkage using
a Bayesian approach in general Besov spaces. Instead of studying the Bayesian
estimator related to a particular loss function, we focus on the posterior
distribution itself from a nonparametric Bayesian asymptotics point of view and
study its rate of convergence. We obtain the same rate as in
\citet{abramovich04} where the authors studied the convergence of several
Bayesian estimators.


title: Flow Field Evolution of a Decaying Sunspot

abstract:
  We study the evolution of the flows and horizontal proper motions in and
around a decaying follower sunspot based on time sequences of two-dimensional
spectroscopic observations in the visible and white light imaging data obtained
over six days from June~7 to~12, 2005. During this time period the sunspot
decayed gradually to a pore. The spectroscopic observations were obtained with
the Fabry-P\'{e}rot based Visible-Light Imaging Magnetograph (VIM) in
conjunction with the high-order adaptive optics (AO) system operated at the 65
cm vacuum reflector of the Big Bear Solar Observatory (BBSO). We apply local
correlation tracking (LCT) to the speckle reconstructed time sequences of
white-light images around 600 nm to infer horizontal proper motions while the
Doppler shifts of the scanned \FeI line at 630.15 nm are used to calculate
line-of-sight (LOS) velocities with sub-arcsecond resolution. We find that the
dividing line between radial inward and outward proper motions in the inner and
outer penumbra, respectively, survives the decay phase. In particular the moat
flow is still detectable after the penumbra disappeared. Based on our
observations three major processes removed flux from the sunspot: (a)
fragmentation of the umbra, (b) flux cancelation of moving magnetic features
(MMFs; of the same polarity as the sunspot) that encounter the leading opposite
polarity network and plages areas, and (c) flux transport by MMFs (of the same
polarity as the sunspot) to the surrounding network and plage regions that have
the same polarity as the sunspot.


title: The QCD potential

abstract:
  After reviewing the definition of the heavy quark-antiquark potential in
pNRQCD, we discuss recent advances in the calculation.


title: Microscopic formulation of the S-matrix in AdS/CFT

abstract:
  We develop the derivation we proposed in hep-th/0703177 of the dressing phase
of the S-matrix in the AdS/CFT correspondence in the framework of the
underlying bare integrable model. We elaborate the configuration of the Bethe
roots describing the physical vacuum, which consists of a long Bethe string
stretched along the imaginary axis and stacks distributed along the real axis.
We determine the distribution of all Bethe roots in the thermodynamic limit. We
then directly compute the scattering phase of the fundamental excitations over
the physical vacuum and reproduce the BHL/BES dressing phase.


title: On the Schwartz space isomorphism theorem for rank one symmetric space

abstract:
  In this paper we give a simpler proof of the $L^p$-Schwartz space isomorphism
$(0< p\leq 2)$ under the Fourier transform for the class of functions of left
$\delta$-type on a Riemannian symmetric space of rank one. Our treatment rests
on Anker's \cite{A} proof of the corresponding result in the case of left
$K$-invariant functions on $X$. Thus we give a proof which relies only on the
Paley--Wiener theorem.


title:
On the cohomology of orbit space of free \pmb{${\ZZ}_{p}$}-actions on
  lens spaces

abstract:
  Let $G = \ZZ_p$, $p$ an odd prime, act freely on a finite-dimensional
CW-complex $X$ with mod $p$ cohomology isomorphic to that of a lens space
$L^{2m-1} (p;q_1,...,q_m)$. In this paper, we determine the mod $p$ cohomology
ring of the orbit space $X/G$, when $p^2\nmid m$.


title:
Approximation of functions of two variables by certain linear positive
  operators

abstract:
  We introduce certain linear positive operators and study some approximation
properties of these operators in the space of functions, continuous on a
compact set, of two variables. We also find the order of this approximation by
using modulus of continuity. Moreover we define an $r$th order generalization
of these operators and observe its approximation properties. Furthermore, we
study the convergence of the linear positive operators in a weighted space of
functions of two variables and find the rate of this convergence using weighted
modulus of continuity.


title: On an inequality concerning the polar derivative of a polynomial

abstract:
  In this paper, we present a correct proof of an $L_p$-inequality concerning
the polar derivative of a polynomial with restricted zeros. We also extend
Zygmund's inequality to the polar derivative of a polynomial.


abstract:
  Let $\phi$ be an analytic self-map and $u$ be a fixed analytic function on
the open unit disk $D$ in the complex plane $\CC.$ The weighted composition
operator is defined\break by \begin{equation*} uC_\phi f =u \cdot (f\circ
\phi), f \in H(D). \end{equation*} Weighted composition operators from
Bergman-type spaces into Bloch spaces and little Bloch spaces are characterized
by function theoretic properties of their inducing maps.


title: A generalization of d'Alembert formula

abstract:
  In this paper we find a closed form of the solution for the factored
inhomogeneous linear equation \begin{equation*}
\prod_{j=1}^{n}(\frac{\hbox{d}}{\hbox{d}t}-A_{j}) u(t) =f(t). \end{equation*}
Under the hypothesis $A_{1},A_{2}, ..., A_{n}$ are infinitesimal generators of
mutually commuting strongly continuous semigroups of bounded linear operators
on a Banach space $X$. Here we do not assume that $A_{j}$s are distinct and we
offer the computational method to get explicit solutions of certain partial
differential equations.


title:
A sharp upper bound for the first eigenvalue of the Laplacian of compact
  hypersurfaces in rank-1 symmetric spaces

abstract:
  Let $M$ be a closed hypersurface in a simply connected rank-1 symmetric space
$\olm$. In this paper, we give an upper bound for the first eigenvalue of the
Laplacian of $M$ in terms of the Ricci curvature of $\olm$ and the square of
the length of the second fundamental form of the geodesic spheres with center
at the center-of-mass of $M$.


title: Equivariant embeddings of Hermitian symmetric spaces

abstract:
  We prove that equivariant, holomorphic embeddings of Hermitian symmetric
spaces are totally geodesic (when the image is not of exceptional type).


title:
A succession of relaxor ferroelectric transitions coexisting with
  ferroelectric states in Ba_0.55Sr_0.45TiO_3

abstract:
  We present here the results of frequency dependent dielectric, polarization
and powder X-ray powder diffraction studies in the 300 to 100K temperature
range for Ba_0.55Sr_0.45TiO_3. The dielectric results indicate a succession of
three relaxor ferroelectric transitions accompanying the cubic to tetragonal to
orthorhombic to rhombohedral phase transitions confirmed by XRD studies. Our
results confirm the coexistence of the relaxor ferroelectric and ferroelectric
behaviours.


title:
Relation between fundamental estimation limit and stability in linear
  quantum systems with imperfect measurement

abstract:
  From the noncommutative nature of quantum mechanics, estimation of canonical
observables $\hat{q}$ and $\hat{p}$ is essentially restricted in its
performance by the Heisenberg uncertainty relation, $\mean{\Delta
\hat{q}^2}\mean{\Delta \hat{p}^2}\geq \hbar^2/4$. This fundamental lower-bound
may become bigger when taking the structure and quality of a specific
measurement apparatus into account. In this paper, we consider a particle
subjected to a linear dynamics that is continuously monitored with efficiency
$\eta\in(0,1]$. It is then clarified that the above Heisenberg uncertainty
relation is replaced by $\mean{\Delta \hat{q}^2}\mean{\Delta \hat{p}^2}\geq
\hbar^2/4\eta$ if the monitored system is unstable, while there exists a stable
quantum system for which the Heisenberg limit is reached.


title: A trivial observation on time reversal in random matrix theory

abstract:
  It is commonly thought that a state-dependent quantity, after being averaged
over a classical ensemble of random Hamiltonians, will always become
independent of the state. We point out that this is in general incorrect: if
the ensemble of Hamiltonians is time reversal invariant, and the quantity
involves the state in higher than bilinear order, then we show that the
quantity is only a constant over the orbits of the invariance group on the
Hilbert space. Examples include fidelity and decoherence in appropriate models.


title:
Some notes on the equivalence of first-order rigidity in various
  geometries

abstract:
  These pages serve two purposes. First, they are notes to accompany the talk
"Hyperbolic and projective geometry in constraint programming for CAD" by
Walter Whiteley at the "Janos Bolyai Conference on Hyperbolic Geometry", 8--12
July 2002, in Budapest, Hungary. Second, they sketch results that will be
included in a forthcoming paper that will present the equivalence of the
first-order rigidity theories of bar-and-joint frameworks in various
geometries, including Euclidean, hyperbolic and spherical geometry. The bulk of
the theory is outlined here, with remarks and comments alluding to other
results that will make the final version of the paper.


title: On the Gauss Map with Vanishing Biharmonic stress-energy tensor

abstract:
  We study the biharmonic stress-energy tensor $S_2$ of Gauss map. Adding few
assumptions, the Gauss map with vanishing $S_2$ would be harmonic.


title:
Discovery of Par 1802 as a Low-Mass, Pre-Main-Sequence Eclipsing Binary
  in the Orion Star-Forming Region

abstract:
  We report the discovery of a pre-main-sequence, low-mass, double-lined,
spectroscopic, eclipsing binary in the Orion star-forming region. We present
our observations including radial velocities derived from optical
high-resolution spectroscopy, and present an orbit solution that permits the
determination of precise empirical masses for both components of the system. We
measure that Par 1802 is composed of two equal mass (0.39+-0.03, 0.40+-0.03
Msun) stars in a circular, 4.7 day orbit. There is strong evidence, such as the
system exhibiting strong Li lines and a center-of-mass velocity consistent with
cluster membership, that this system is a member of the Orion star-forming
region and quite possibly the Orion Nebula Cluster, and therefore has an age of
only a few million years. As there are currently only a few empirical mass and
radius measurements for low-mass, PMS stars, this system presents an
interesting test for the predictions of current theoretical models of pre-main
sequence stellar evolution.


title: Spectrum of the non-commutative spherical well

abstract:
  We give precise meaning to piecewise constant potentials in non-commutative
quantum mechanics. In particular we discuss the infinite and finite
non-commutative spherical well in two dimensions. Using this, bound-states and
scattering can be discussed unambiguously. Here we focus on the infinite well
and solve for the eigenvalues and eigenfunctions. We find that time reversal
symmetry is broken by the non-commutativity. We show that in the commutative
and thermodynamic limits the eigenstates and eigenfunctions of the commutative
spherical well are recovered and time reversal symmetry is restored.


title:
Polarization-independent CP-odd Observable in e^+e^- Chargino Production
  at One Loop

abstract:
  We discuss CP violation in the process e^+e^- \to
\tilde\chi^+_i\tilde\chi^-_j with unpolarized beams. When the scalars are
heavy, the box-diagram results constitute a major part of the full result.
However, there are situations when the vertex and self-energy corrections
dominate over the box diagrams. We also comment on CP violation in the final
chargino decay.


title:
Transition states in protein folding kinetics: Modeling Phi-values of
  small beta-sheet proteins

abstract:
  Small single-domain proteins often exhibit only a single free-energy barrier,
or transition state, between the denatured and the native state. The folding
kinetics of these proteins is usually explored via mutational analysis. A
central question is which structural information on the transition state can be
derived from the mutational data. In this article, we model and structurally
interpret mutational Phi-values for two small beta-sheet proteins, the PIN and
the FBP WW domain. The native structure of these WW domains comprises two
beta-hairpins that form a three-stranded beta-sheet. In our model, we assume
that the transition state consists of two conformations in which either one of
the hairpins is formed. Such a transition state has been recently observed in
Molecular Dynamics folding-unfolding simulations of a small designed
three-stranded beta-sheet protein. We obtain good agreement with the
experimental data (i) by splitting up the mutation-induced free-energy changes
into terms for the two hairpins and for the small hydrophobic core of the
proteins, and (ii) by fitting a single parameter, the relative degree to which
hairpin 1 and 2 are formed in the transition state. The model helps to
understand how mutations affect the folding kinetics of WW domains, and
captures also negative Phi-values that have been difficult to interpret.


title: A non-monotone conservation law for dune morphodynamics

abstract:
  We investigate a non-local non linear conservation law, first introduced by
A.C. Fowler to describe morphodynamics of dunes, see \cite{Fow01, Fow02}. A
remarkable feature is the violation of the maximum principle, which allows for
erosion phenomenon. We prove well-posedness for initial data in $L^2$ and give
explicit counterexample for the maximum principle. We also provide numerical
simulations corroborating our theoretical results.


title: On a property of the number 977731833235239280

abstract:
  We solve a theoretical arithmetics problem stated by Wac{\l}aw Sierpi\'nski.
The problem has remained open for a couple of decades.


title: Standard-smooth hybrid inflation

abstract:
  We consider the extended supersymmetric Pati-Salam model which, for mu>0 and
universal boundary conditions, succeeds to yield experimentally acceptable
b-quark masses by moderately violating Yukawa unification. It is known that
this model can lead to new shifted or new smooth hybrid inflation. We show that
a successful two-stage inflationary scenario can be realized within this model
based only on renormalizable superpotential interactions. The cosmological
scales exit the horizon during the first stage of inflation, which is of the
standard hybrid type and takes place along the trivial flat direction with the
inflaton driven by radiative corrections. Spectral indices compatible with the
recent data can be achieved in global supersymmetry or minimal supergravity by
restricting the number of e-foldings of our present horizon during the first
inflationary stage. The additional e-foldings needed for solving the horizon
and flatness problems are naturally provided by a second stage of inflation,
which occurs mainly along the built-in new smooth hybrid inflationary path
appearing right after the destabilization of the trivial flat direction at its
critical point. Monopoles are formed at the end of the first stage of inflation
and are, subsequently, diluted by the second stage of inflation to become
utterly negligible in the present universe for almost all (for all) the allowed
values of the parameters in the case of global supersymmetry (minimal
supergravity).


title: Can a resonance theory be a renormalizable theory?

abstract:
  In this talk we make an exhaustive analysis of the possible chiral invariant
operators that may described the resonance decay S->pi pi. These provide at the
same time the only available chiral invariant structures for the loop
ultraviolet divergences in this amplitude. Independently of the order in
perturbation theory, we find just one single-trace term (four if multi-trace
operators are allowed), whose renormalization renders the matrix element
finite.


title: Baryon Modes of B Meson Decays

abstract:
  The baryon decay modes of B,bar{B}-> N_{1}bar{N}_{2}(f),
bar{N}_{1}N_{2}(bar{f}) provide a frame work to test CP-invariance in baryon
sector. It is shown that in the rest frame of B, N_{1} and bar{N}_{2} come out
with longitudnal polarization lambda_{1}=lambda_{2}=\pm 1 with decay width
Gamma_{f}=Gamma_{f}^{++}+Gamma_{f}^{--} and the asymmetry parameter alpha
_{f}=\Delta \Gamma_{f}=\Gamma_{f}^{++}-Gamma_{f}^{--} . It is shown that CP
invariance prediction alpha_{f}=-\bar{alpha}_{bar{f}} can be tested in these
decay modes; especially in the time dependent decays of
B_{q}^{0}-bar{B}_{q}^{0} complex. Apart from this, it is shown that decay modes
B(bar{B})->N_{1}bar{N}_{2}(bar{N}_{1}N_{2}) and subsequent non leptonic decays
of N_{2},bar{N}_{2} or (N_{1},bar{N}_{1}) into hyperon (antihyperon) also
provide a frame work to study CP-odd observables in hyperon decays.


title:
A deep Large Binocular Telescope view of the Canes Venatici I dwarf
  galaxy

abstract:
  We present the first deep color-magnitude diagram of the Canes Venatici I
(CVnI) dwarf galaxy from observations with the wide field Large Binocular
Camera on the Large Binocular Telescope. Reaching down to the main-sequence
turnoff of the oldest stars, it reveals a dichotomy in the stellar populations
of CVnI: it harbors an old (> 10 Gyr), metal-poor ([Fe/H] ~ -2.0) and spatially
extended population along with a much younger (~ 1.4-2.0 Gyr), 0.5 dex more
metal-rich, and spatially more concentrated population. These young stars are
also offset by 64_{-20}^{+40} pc to the East of the galaxy center. The data
suggest that this young population, which represent ~ 3-5 % of the stellar mass
of the galaxy within its half-light radius, should be identified with the
kinematically cold stellar component found by Ibata et al. (2006). CVnI
therefore follows the behavior of the other remote MW dwarf spheroidals which
all contain intermediate age and/or young populations: a complex star formation
history is possible in extremely low-mass galaxies.


title: Jozso's Legacy: Chemical and Kinetic Freeze-out in Heavy-Ion Collisions

abstract:
  We review J. Zimanyi's key contributions to the theoretical understanding of
dynamical freeze-out in nuclear collisions and their subsequent applications to
ultra-relativistic heavy-ion collisions, leading to the discovery of a
freeze-out hierarchy where chemical freeze-out of hadron yields precedes the
thermal decoupling of their momentum spectra. Following Zimanyi's lines of
reasoning we show that kinetic freeze-out necessarily leads to a dependence of
the corresponding freeze-out temperature on collision centrality. This
centrality dependence can be predicted within hydrodynamic models, and for
Au+Au collisions at RHIC this prediction is shown to reproduce the
experimentally observed centrality dependence of the thermal decoupling
temperature, extracted from hadron momentum spectra. The fact that no such
centrality dependence is observed for the chemical decoupling temperature,
extracted from the hadron yields measured in these collisions, excludes a
similar kinetic interpretation of the chemical decoupling process. We argue
that the chemical decoupling data from Au+Au collisions at RHIC can only be
consistently understood if the chemical freeze-out process is driven by a phase
transition, and that the measured chemical decoupling temperature therefore
measures the critical temperature of the quark-hadron phase transition. We
propose additional experiments to further test this interpretation.


title:
Implementing Few-Body Algorithmic Regularization with Post-Newtonian
  Terms

abstract:
  We discuss the implementation of a new regular algorithm for simulation of
the gravitational few-body problem. The algorithm uses components from earlier
methods, including the chain structure, the logarithmic Hamiltonian, and the
time-transformed leapfrog. This algorithmic regularization code, AR-CHAIN, can
be used for the normal N-body problem, as well as for problems with softened
potentials and/or with velocity-dependent external perturbations, including
post-Newtonian terms, which we include up to order PN2.5. Arbitrarily extreme
mass ratios are allowed. Only linear coordinate transformations are used and
thus the algorithm is somewhat simpler than many earlier regularized schemes.
We present the results of performance tests which suggest that the new code is
either comparable in performance or superior to the existing regularization
schemes based on the Kustaanheimo-Stiefel (KS) transformation. This is true
even for the two-body problem, independent of eccentricity. An important
advantage of the new method is that, contrary to the older KS-CHAIN code, zero
masses are allowed. We use our algorithm to integrate the orbits of the S stars
around the Milky Way supermassive black hole for one million years, including
PN2.5 terms and an intermediate-mass black hole. The three S stars with
shortest periods are observed to escape from the system after a few hundred
thousand years.


title: Track Based Alignment in CMS

abstract:
  The strategy for track based alignment of the CMS tracking and muon detectors
is presented. After an overview over the used data samples, the general
alignment strategy is presented, with a focus of the procedures envisaged at
the start of data taking in 2008. The three currently used alignment algorithms
are discussed and first results on their application to the CMS tracker are
presented, as well as studies on the alignment of the Muon detector with
tracks.


title: On the magnetically driven ferroelectric phase in GdMnO3

abstract:
  At room temperature, GdMnO3 is a paraelectric and paramagnetic with a
distorted perovskite structure of orthorhombic symmetry (space group Pnma). On
cooling, it undergoes a phase transition sequence to a magnetic incommensurate
phase (k=delta a*; Tc1=42K) and a A-type antiferromagnetic phase (Tc2=27K). At
low temperatures (T<12K), a magnetic field applied along the a-axis
destabilizes the antiferromagnetic phase and induces a first order transition
to a magnetic commensurate modulated phase (delta=1/4) that is also
ferroelectric (P//c). This work analyses this field induced phase transition
from the point of view of the symmetry and Landau theory.


title: Nucleon form factors on the lattice with light dynamical fermions

abstract:
  The electromagnetic form factors provide important insight into the internal
structure of the nucleon and continue to be of major interest for experiment
and phenomenology. For an intermediate range of momenta the form factors can be
calculated on the lattice. However, the reliability of the results is limited
by systematic errors mostly due to the required extrapolation to physical quark
masses. Chiral effective field theories predict a rather strong quark mass
dependence in a range which was yet inaccessible for lattice simulations. We
give an update on recent results from the QCDSF collaboration using gauge
configurations with dynamical Nf=2, non-perturbatively O(a)-improved Wilson
fermions at pion masses as low as 350 MeV.


title:
Search for the C-parity violating process J/psi->gamma gamma via
  psi(2S)->pi+pi- J/psi

abstract:
  Using 14.0\times 10^6 \psi(2S) events collected with the BES-II detector, the
C-parity violating process J/psi->gamma gamma via psi(2S)->pi+pi- J/psi is
studied. We determine a new upper limit for the J/psi->gamma gamma branching
ratio of B(J/psi->gamma gamma)<2.2\times 10^{-5} at the 90% C.L., which is
about 20 times lower than the previous measurement.


title:
Two-dimensional Radiation-hydrodynamic Model for Supercritical Disk
  Accretion Flows onto Neutron Stars

abstract:
  We performed two-dimensional radiation hydrodynamic simulations of
supercritical accretion flows around neutron stars (NSs). In contrast with the
accretion flows onto black holes (BHs), we find that the shell-shaped
high-density regions form around the NSs, since the radiation force is enhanced
in the innermost regions. The enhanced radiation force drives strong outflows
above and below the disk. The mass-accretion rate onto the NS exceeds the
critical rate, $L_{\rm E}/c^2$, with $L_{\rm E}$ being the Eddington
luminosity. However it is about $20-30%$ of that onto the BH, under the
condition that we employ the same mass-input rate, $\dot{M}_{\rm input}$, which
is mass injected from the outer disk boundary per unit time. The mass-outflow
rate is a few-times larger in flows around NSs than in flows around BHs. The
supercritical NS accretion flows mainly release the accretion energy as the
kinetic energy of the outflows, though the disk luminosity is predominant over
the kinetic energy output rate in the BH accretion flows. The resulting
velocity and mass-outflow rate of the outflows are $0.2-0.3c$ and
$150-700L_{\rm E}/c^2$, respectively, for the mass-input rate of $3\times
10^2\lsim \dot{M}_{\rm input}/(L_{\rm E}/c^2)\lsim 3\times 10^3$. This implies
that the SS433 jets can be roughly explained by the supercritical accretion
onto a NS. However, the collimation angle of the outflows in our simulations
($\sim 20^\circ$) is larger than that of the SS433 jets (a few degrees).


title: Hyperbolicity of general deformations: proofs

abstract:
  We modify the deformation method explored previously in a joint work of B.
Shiffman and the author, in order to construct further examples of Kobayashi
hyperbolic surfaces in the projective 3-space of any even degree starting with
degree 8.


title: Local equivalence of symmetric hypersurfaces in $\mathbb C^2$

abstract:
  The Chern-Moser normal form and its analog on finite type hypersurfaces in
general do not respect symmetries. Extending the work of N. K. Stanton, we
consider the local equivalence problem for symmetric Levi degenerate
hypersurfaces of finite type in $\mathbb C^2$. The results give for all such
hypersurfaces a complete normalization which respects the symmetries. In
particular, they apply to tubes and rigid hypersurfaces, providing an effective
classification. The main tool is a complete normal form constructed for a
general hypersurface with a tube model. As an application, we describe all
biholomorphic maps between tubes, answering a question posed by N. Hanges.


title: Compatible Geometric Matchings

abstract:
  This paper studies non-crossing geometric perfect matchings. Two such perfect
matchings are \emph{compatible} if they have the same vertex set and their
union is also non-crossing. Our first result states that for any two perfect
matchings $M$ and $M'$ of the same set of $n$ points, for some $k\in\Oh{\log
n}$, there is a sequence of perfect matchings $M=M_0,M_1,...,M_k=M'$, such that
each $M_i$ is compatible with $M_{i+1}$. This improves the previous best bound
of $k\leq n-2$. We then study the conjecture: \emph{every perfect matching with
an even number of edges has an edge-disjoint compatible perfect matching}. We
introduce a sequence of stronger conjectures that imply this conjecture, and
prove the strongest of these conjectures in the case of perfect matchings that
consist of vertical and horizontal segments. Finally, we prove that every
perfect matching with $n$ edges has an edge-disjoint compatible matching with
approximately $4n/5$ edges.


title: Bar formation and galaxy interactions in MOND

abstract:
  The LCDM model is the most commonly admitted to describe our Universe. In
spite of a great success with regard to the large scale structure formation,
some problems are still unresolved at galactic scales. Alternative scenarios
have to be explored such as modified gravity. We have developed an N-body code
able to solve in a self consistent way the galactic dynamics in MOND. The first
version of the code consists in solving the modified Poisson equation on a
uniform Cartesian grid to derive the gravitational force on each particle. With
it, we study the evolution of isolated galaxies, like the bar instability, the
angular momentum transfer, etc. Galaxies in MOND are found to form stronger
bars, faster than in Newtonian dynamics with dark matter. In a second step, we
implement an adaptive mesh refinement technique in the code, allowing to run
more contrasted simulations on larger scales, like interacting galaxies. During
an interaction, the dynamical friction forces are less important in MOND, and
merging times are longer than in DM models. The different morphologies of
interacting galaxies in the two models are discussed. All simulations are
performed in both frameworks of modified gravity and Newtonian gravity with
dark matter with equivalent initial conditions.


title: Algebraic causality: Bayes nets and beyond

abstract:
  The relationship between algebraic geometry and the inferential framework of
the Bayesian Networks with hidden variables has now been fruitfully explored
and exploited by a number of authors. More recently the algebraic formulation
of Causal Bayesian Networks has also been investigated in this context. After
reviewing these newer relationships, we proceed to demonstrate that many of the
ideas embodied in the concept of a ``causal model'' can be more generally
expressed directly in terms of a partial order and a family of polynomial maps.
The more conventional graphical constructions, when available, remain a
powerful tool.


title: Intersection numbers of Riemann surfaces from Gaussian matrix models

abstract:
  We consider a Gaussian random matrix theory in the presence of an external
matrix source. This matrix model, after duality (a simple version of the
closed/open string duality), yields a generalized Kontsevich model through an
appropriate tuning of the external source. The n-point correlation functions of
this theory are shown to provide the intersection numbers of the moduli space
of curves with a p-spin structure, n marked points and top Chern class. This
sheds some light on Witten's conjecture on the relationship with the pth-KdV
equation.


title: Luescher-Weisz algorithm for excited states of the QCD flux-tube

abstract:
  We present a version of the Luescher-Weisz multilevel algorithm ideally
suited for studying excited states of the QCD flux tube. While the original
version achieved error reduction only in the temporal direction, the new
algorithm reduces fluctuations in the sources as well. We report on the
implementation of this algorithm as well as improvement over the older method.
We also present first results, where we see a good agreement with theoretical
predictions from bosonic string models.


title: The causal manipulation of chain event graphs

abstract:
  Discrete Bayesian Networks have been very successful as a framework both for
inference and for expressing certain causal hypotheses. In this paper we
present a class of graphical models called the chain event graph (CEG) models,
that generalises the class of discrete BN models. It provides a flexible and
expressive framework for representing and analysing the implications of causal
hypotheses, expressed in terms of the effects of a manipulation of the
generating underlying system. We prove that, as for a BN, identifiability
analyses of causal effects can be performed through examining the topology of
the CEG graph, leading to theorems analogous to the back-door theorem for the
BN.


title: Generalized ABCD propagation for interacting atomic clouds

abstract:
  We present a treatment of the nonlinear matter wave propagation inspired from
optical methods, which includes interaction effects within the atom optics
equivalent of the aberrationless approximation. The atom-optical ABCD matrix
formalism, considered so far for non-interacting clouds, is extended
perturbatively beyond the linear regime of propagation. This approach, applied
to discuss the stability of a matter-wave resonator involving a free-falling
sample, agrees very well with the predictions of the full nonlinear paraxial
wave equation. An alternative optical treatment of interaction effects, based
on the aberrationless approximation and suitable for cylindrical paraxial beams
of uniform linear density, is also adapted for matter waves.

categories: cond-mat.quant-gas cond-mat.other physics.atom-ph physics.optics quant-ph


title:
Spin-Peierls transition in carbynoid conductors: infrared absorption
  study

abstract:
  The results of IR-studies in quasi-1D carbynoid films produced by
dehydrohalogenation of poly(vinilidene fluoride) are in good agreement with the
assumption that carbynoid films studied are generalized spin -Peierls
conductors, the metal to insulator transition in which can be described in the
frame of t-J model. Residual atoms of fluorine, hydrogen and atoms of main
technological impurity oxygen in the form of various complexes in interchain
space are suggested to be spin - (or joint spin - and electrical) conductivity
dopants. Antiferroelectric spin wave resonance (AFESWR) being to be optical
analogue of antiferromagnetic spin wave resonance has been identified for the
first time. Electric spin-Peierls polaron lattice in C-C -bonds is proposed to
be responsible for the observed AFESWR both in starting PWDF films and in
carbynoid B-films (the samples with the least impurity content). Electric spin
moment with pure imaginary value predicted by Dirac as early as 1928 was
identified for the first time. Electric spin-Peierls polarons are proposed to
be electric spin moment carriers. It has been established that topological
solitons, earlier called spin-Peierls solitons (SPS), are simultaneously
active, unlike to topological solitons with nonzero spin in
\textit{trans}-polyacetylene, in both optical and magnetic resonance spectra.It
is explained in suggestion that SPS possess by both electric and magnetic spin
moments which can be considered as two components of complex electromagnetic
spin vector as a single whole. SPS proposed to be consisting of two coupled
domain walls in both magnetic and electric generalized spin density wave
(GSDW), produced by electromagnetic spin-Peierls transition in its generalized
form in $\pi$ - and $\sigma$ -subsystems of carbynoids.


title:
n-Dimensional geometric-shifted global bilinear correspondences of
  Langlands on mixed motives III

abstract:
  This third paper,devoted to global correspondences of Langlands,bears more
particularly on geometric-shifted bilinear correspondences on mixed (bi)motives
generated under the action of the products,right by left,of differential
elliptic operators.The mathematical frame,underlying these
correspondences,deals with the categories of the Suslin-Voevodsky mixed
(bi)motives and of the Chow mixed (bi)motives which are both in one-to-one
correspondence with the functional representation spaces of the shifted
algebraic bilinear semigroups.A bilinear holomorphic and supercuspidal spectral
representation of an elliptic bioperator is then developed.


title: Weighted Matching in the Semi-Streaming Model

abstract:
  We reduce the best known approximation ratio for finding a weighted matching
of a graph using a one-pass semi-streaming algorithm from 5.828 to 5.585. The
semi-streaming model forbids random access to the input and restricts the
memory to O(n*polylog(n)) bits. It was introduced by Muthukrishnan in 2003 and
is appropriate when dealing with massive graphs.


title:
Mass generation of elementary particles and origin of the fundamental
  forces in algebraic quantum theory

abstract:
  The main thesis of this paper deals with the interactions of a set of
fermions which are described by one basic type of bilinear interactions,two
symmetric semiobjects,three embedded shells and four fundamental (strong)
gravito-electro-magnetic forces between left and right semiobjects,i.e
semifermions.


title:
Exploring the transition into the Chiral Regime of QCD using the
  Interacting Instanton Liquid Model

abstract:
  The non-perturbative quark-gluon interaction depends significantly on the
value of the quark mass. In particular, in the light quark mass regime,
correlations are strongly influenced by dynamics associated to chiral symmetry
breaking. We use the Interacting Instanton Liquid Model (IILM) as a tool to
investigate the microscopic dynamical mechanisms which underly the dependence
on the quark mass and drive the transition into the chiral regime of QCD. To
ensure the validity of the model, we first verify that the dependence on the
quark mass for several observables calculated in the IILM agrees well with the
predictions of chiral perturbation theory and with lattice simulations. We then
show that a quark mass m*~80 MeV emerging naturally from the model specifies
the mass scale above which the dynamics associated with low-lying eigenmodes of
the Direac operator becomes sub-leading and the contribution of the fermion
determinant is suppressed.


title: Finite-Dimensional Calculus

abstract:
  We discuss topics related to finite-dimensional calculus in the context of
finite-dimensional quantum mechanics. The truncated Heisenberg-Weyl algebra is
called a TAA algebra after Tekin, Aydin, and Arik who formulated it in terms of
orthofermions. It is shown how to use a matrix approach to implement analytic
representations of the Heisenberg-Weyl algebra in univariate and multivariate
settings. We provide examples for the univariate case. Krawtchouk polynomials
are presented in detail, including a review of Krawtchouk polynomials that
illustrates some curious properties of the Heisenberg-Weyl algebra, as well as
presenting an approach to computing Krawtchouk expansions. From a mathematical
perspective, we are providing indications as to how to implement in finite
terms Rota's "finite operator calculus".


title: Loop-closure principles in protein folding

abstract:
  Simple theoretical concepts and models have been helpful to understand the
folding rates and routes of single-domain proteins. As reviewed in this
article, a physical principle that appears to underly these models is loop
closure.


title: Gauge Variant Symmetries for the Schr\"odinger Equation

abstract:
  The last multiplier of Jacobi provides a route for the determination of
families of Lagrangians for a given system. We show that the members of a
family are equivalent in that they differ by a total time derivative. We derive
the Schr\"odinger equation for a one-degree-of-freedom system with a constant
multiplier. In the sequel we consider the particular example of the simple
harmonic oscillator. In the case of the general equation for the simple
harmonic oscillator which contains an arbitrary function we show that all
Schr\"odinger equations possess the same number of Lie point symmetries with
the same algebra. From the symmetries we construct the solutions of the
Schr\"odinger equation and find that they differ only by a phase determined by
the gauge.


title: Composition of UHECR and the Pierre Auger Observatory Spectrum

abstract:
  We fit the recently published Pierre Auger ultra-high energy cosmic ray
spectrum assuming that either nucleons or nuclei are emitted at the sources. We
consider the simplified cases of pure proton, or pure oxygen, or pure iron
injection. We perform an exhaustive scan in the source evolution factor, the
spectral index, the maximum energy of the source spectrum Z E_{max}, and the
minimum distance to the sources. We show that the Pierre Auger spectrum agrees
with any of the source compositions we assumed. For iron, in particular, there
are two distinct solutions with high and low E_{max} (e.g. 6.4 10^{20} eV and 2
10^{19} eV) respectively which could be distinguished by either a large
fraction or the near absence of proton primaries at the highest energies. We
raise the possibility that an iron dominated injected flux may be in line with
the latest composition measurement from the Pierre Auger Observatory where a
hint of heavy element dominance is seen.


title:
General relativity, Lauricella's hypergeometric function $F_D$ and the
  theory of braids

abstract:
  The exact (closed form) solutions of the equations of motion in the theory of
general relativity that describe motion of test particle and photon in Kerr and
Kerr-(anti) de Sitter spacetimes all involve the multivariable hypergeometric
function of Lauricella $F_D$: Kraniotis [Class. Quantum Grav. {\bf 21} 2004,
4743; Class. Quantum Grav. {\bf 22} 2005, 4391; Class. Quantum Grav. {\bf 24}
2007, 1775]. The domain of variables ${\cal D}_n$ of the corresponding function
depends on the first integrals of motion associated with the isometries of the
Kerr-(anti) de Sitter metric and Carter's constant $Q$ as well as on the
cosmological constant $\Lambda$ and the Kerr (rotation) parameter. In this work
we discuss the topological properties of the domain ${\cal D}_n$ and in
particular its fundamental connection with the theory of braids. An intrinsic
relationship of general relativity with the pure braids is established.


title:
Optimally localized Wannier functions for quasi one-dimensional
  nonperiodic insulators

abstract:
  It is proved that for general, not necessarily periodic quasi one dimensional
systems, the band position operator corresponding to an isolated part of the
energy spectrum has discrete spectrum and its eigenfunctions have the same
spatial localization as the corresponding spectral projection.
  As a consequence, an eigenbasis of the band position operator provides a
basis of optimally localized (generalized) Wannier functions for quasi one
dimensional systems, thus proving the "strong conjecture" of Marzari and
Vanderbilt. If the system has some translation symmetries (e.g. usual
translations, screw transformations), they are "inherited" by the Wannier
basis.


title: Pulsation of EE Cam

abstract:
  EE Cam is a previously little studied Delta Scuti pulsator with amplitudes
between those of the HADS (High-Amplitude Delta Scuti stars) group and the
average low-amplitude pulsators. Since the size of stellar rotation determines
both which pulsation modes are selected by the star as well as their
amplitudes, the star offers a great opportunity to examine the astrophysical
connections. Extensive photometric measurements covering several months were
carried out. 15 significant pulsation frequencies were extracted. The dominant
mode at 4.934 cd$^{-1}$ was identified as a radial mode by examining the phase
shifts at different wavelengths. Medium-dispersion spectra yielded a $v\sin i$
value of $40 \pm 3$ km s$^{-1}$. This shows that EE Cam belongs to the
important transition region between the HADS and normal Delta Scuti stars.


title:
Cluster and nebular properties of the central star-forming region of NGC
  1140

abstract:
  We present new high spatial resolution HST/ACS imaging of NGC 1140 and high
spectral resolution VLT/UVES spectroscopy of its central star-forming region.
The central region contains several clusters, the two brightest of which are
clusters 1 and 6 from Hunter, O'Connell & Gallagher, located within
star-forming knots A and B, respectively. Nebular analysis indicates that the
knots have an LMC-like metallicity of 12 + log(O/H) = 8.29 +/- 0.09. According
to continuum subtracted H alpha ACS imaging, cluster 1 dominates the nebular
emission of the brighter knot A. Conversely, negligible nebular emission in
knot B originates from cluster 6. Evolutionary synthesis modelling implies an
age of 5 +/- 1 Myr for cluster 1, from which a photometric mass of (1.1 +/-
0.3) x 10^6 Msun is obtained. For this age and photometric mass, the modelling
predicts the presence of ~5900 late O stars within cluster 1. Wolf-Rayet
features are observed in knot A, suggesting 550 late-type WN and 200 early-type
WC stars. Therefore, N(WR)/N(O) ~ 0.1, assuming that all the WR stars are
located within cluster 1. The velocity dispersions of the clusters were
measured from constituent red supergiants as sigma ~ 23 +/- 1 km/s for cluster
1 and sigma ~ 26 +/- 1 km/s for cluster 6. Combining sigma with half-light
radii of 8 +/- 2 pc and 6.0 +/- 0.2 pc measured from the F625W ACS image
implies virial masses of (10 +/- 3) x 10^6 Msun and (9.1 +/- 0.8) x 10^6 Msun
for clusters 1 and 6, respectively. The most likely reason for the difference
between the dynamical and photometric masses of cluster 1 is that the velocity
dispersion of knot A is not due solely to cluster 1, as assumed, but has an
additional component associated with cluster 2.


title:
A note on scaling asymptotics for Bohr-Sommerfeld Lagrangian
  submanifolds

abstract:
  An important problem in geometric quantization is that of quantizing certain
classes of Lagrangian submanifolds, so-called Bohr-Sommerfeld Lagrangian
submanifolds, equipped with a smooth half-density. A procedure for this in the
complex projective setting is, roughly speaking, to apply the Szego kernel of
the quantizing line bundle to a certain induced delta function supported on the
submanifold. If the quantizing line bundle L is replaced by its k-th tensor
power, and k tends to infinity, the resulting quantum states u_k concentrate
asymptotically on the submanifold. This note deals with the scaling asymptotics
of the u_k's along the submanifold; in particular, we point out a natural
factorization in the corresponding asymptotic expansion, and provide some
remainder estimates.


title: Cooling of Particle Beams in Storage Rings

abstract: Methods of particle beam cooling are reviewed.


title: Aharonov-Bohm effect for a valley-polarized current in graphene

abstract:
  This is a numerical study of the conductance of an Aharonov-Bohm
interferometer in a tight-binding model of graphene. Two single-mode ballistic
point contacts with zigzag edges are connected by two arms of a hexagonal ring
enclosing a magnetic flux $\Phi$. The point contacts function as valley
filters, transmitting electrons from one valley of the band structure and
reflecting electrons from the other valley. We find, in the wider rings, that
the magnetoconductance oscillations with the fundamental periodicity
$\Delta\Phi=h/e$ are suppressed when the two valley filters have opposite
polarity, while the second and higher harmonics are unaffected or enhanced.
This frequency doubling is interpreted in terms of a larger probability of
intervalley scattering for electrons that travel several times around the ring.
In the narrowest rings the current is blocked for any polarity of the valley
filters, with small, nearly sinusoidal magnetoconductance oscillations.
Qualitatively similar results are obtained if the hexagonal ring is replaced by
a ring with an irregular boundary.


title:
Spatial image of reaction area from scattering.II: On connection between
  the differential cross-sections in transverse momentum and in nearest
  approach parameter

abstract:
  We develop general formalism of how to relate cross-section for exclusive
processes to spatial image of reaction area. More precisely we show how to
determine the spatial distribution of outgoing particles in the space of
so-called nearest approach parameter. This parameter characterizes the position
in the coordinate space the place where the final particle is produced.


title: Two-dimensional discrete solitons in rotating lattices

abstract:
  We introduce a two-dimensional (2D) discrete nonlinear Schr\"{o}dinger (DNLS)
equation with self-attractive cubic nonlinearity in a rotating reference frame.
The model applies to a Bose-Einstein condensate stirred by a rotating strong
optical lattice, or light propagation in a twisted bundle of nonlinear fibers.
Two species of localized states are constructed: off-axis fundamental solitons
(FSs), placed at distance $R$ from the rotation pivot, and on-axis (R=0) vortex
solitons (VSs), with vorticities $% S=1$ and 2. At a fixed value of rotation
frequency $\Omega $, a stability interval for the FSs is found in terms of the
lattice coupling constant $C$, $% 0<C<C_{\mathrm{cr}}(R)$, with monotonically
decreasing $C_{\mathrm{cr}}(R)$. VSs with S=1 have a stability interval,
$\tilde{C}_{\mathrm{cr}%}^{(S=1)}(\Omega)<C<C_{\mathrm{cr}}^{(S=1)}(\Omega)$,
which exists for $% \Omega $ below a certain critical value,
$\Omega_{\mathrm{cr}}^{(S=1)}$. This implies that the VSs with S=1 are
\emph{destabilized} in the weak-coupling limit by the rotation. On the
contrary, VSs with S=2, that are known to be unstable in the standard DNLS
equation, with $\Omega =0$, are \emph{stabilized} by the rotation in region
$0<C<C_{\mathrm{cr}}^{(S=2)}$%, with $C_{\mathrm{cr}}^{(S=2)}$ growing as a
function of $\Omega $. Quadrupole and octupole on-axis solitons are considered
too, their stability regions being weakly affected by $\Omega \neq 0$.


title: First order formalism for spin one fields

abstract:
  We study two general approaches how to describe spin one particles, using
vector and antisymmetric tensor fields within RChT. In this paper we focus on
the question of an equivalence of both ways. The appearing problems lead us to
the introduction of a new type of the description - the first order formalism
which naturally connects both traditional formalisms. Moreover, it gives a more
general result on the level of the effective chiral Lagrangian that contain all
terms from effective chiral Lagrangians in vector and antisymmetric tensor
formulations.


title: Large Deviations in the Superstable Weakly Imperfect Bose Gas

abstract:
  The superstable Weakly Imperfect Bose Gas {(WIBG)} was originally derived to
solve the inconsistency of the Bogoliubov theory of superfluidity. Its
grand-canonical thermodynamics was recently solved but not at {point of} the
{(first order)} phase transition. This paper proposes to close this gap by
using the large deviations formalism and in particular the analysis of the Kac
distribution function. It turns out that, as a function of the chemical
potential, the discontinuity of the Bose condensate density at the phase
transition {point} disappears as a function of the particle density. Indeed,
the Bose condensate continuously starts at the first critical particle density
and progressively grows but the free-energy per particle stays constant until
the second critical density is reached. At higher particle densities, the Bose
condensate density as well as the free-energy per particle both increase
{monotonously}.


title:
Amplified signal response in scale-free networks by collaborative
  signaling

abstract:
  Many natural and artificial two-states signaling devices are connected
forming networks. The information-processing potential of these systems is
usually related to the response to weak external signals. Here, using a network
of overdamped bistable elements, we study the effect of a heterogeneous complex
topology on the signal response. The analysis of the problem in random
scale-free networks, reveals that heterogeneity plays a crucial role in
amplifying external signals. We have contrasted numerical simulations with
analytical calculations in simplified topologies.


title: Enhanced Optical Cooling of Particle Beams in Storage Rings

abstract:
  A method of enhanced optical cooling (EOC) based on nonlinear selective
interaction between particles and theirs amplified undulator radiation wavelets
(URW) in storage rings is discussed. It leads to non-exponential fast damping.
The selectivity is arranged by a moving screen located on the image plane of
the optical system projecting URW there.


title:
Optimization of the Asymptotic Property of Mutual Learning Involving an
  Integration Mechanism of Ensemble Learning

abstract:
  We propose an optimization method of mutual learning which converges into the
identical state of optimum ensemble learning within the framework of on-line
learning, and have analyzed its asymptotic property through the statistical
mechanics method.The proposed model consists of two learning steps: two
students independently learn from a teacher, and then the students learn from
each other through the mutual learning. In mutual learning, students learn from
each other and the generalization error is improved even if the teacher has not
taken part in the mutual learning. However, in the case of different initial
overlaps(direction cosine) between teacher and students, a student with a
larger initial overlap tends to have a larger generalization error than that of
before the mutual learning. To overcome this problem, our proposed optimization
method of mutual learning optimizes the step sizes of two students to minimize
the asymptotic property of the generalization error. Consequently, the
optimized mutual learning converges to a generalization error identical to that
of the optimal ensemble learning. In addition, we show the relationship between
the optimum step size of the mutual learning and the integration mechanism of
the ensemble learning.


title: Identifying pulsation modes from two-passband photometry

abstract:
  I discuss a prospect for mode identification from two-passband photometry of
forthcoming BRITE space mission. Examples of photometric diagnostic diagrams
are shown for three types of main sequence pulsating variables: $\beta$ Cephei,
Slowly Pulsating B-type and $\delta$ Scuti stars. I consider also taking into
account the radial velocity data from simultaneous spectroscopy, which can be
carried out from the ground. With such observations, much better discrimination
of the spherical harmonic degree, $\ell$, can be accomplished and more
constraints on stellar parameters and input physics can be derived.


title: Equal Superposition Transformations and Quantum Random Walks

abstract:
  The largest ensemble of qubits which satisfy the general transformation of
equal superposition is obtained by different methods, namely, linearity,
no-superluminal signalling and non-increase of entanglement under LOCC. We also
consider the associated quantum random walk and show that all unitary balanced
coins give the same asymmetric spatial probability distribution. It is further
illustrated that unbalanced coins, upon appropriate superposition, lead to new
unbiased walks which have no classical analogues.


title: Non-commutative residue of projections in Boutet de Monvel's calculus

abstract:
  Using results by Melo, Nest, Schick, and Schrohe on the K-theory of Boutet de
Monvel's calculus of boundary value problems, we show that the non-commutative
residue introduced by Fedosov, Golse, Leichtnam, and Schrohe vanishes on
projections in the calculus. This partially answers a question raised in a
recent collaboration with Grubb, namely whether the residue is zero on
sectorial projections for boundary value problems: This is confirmed to be true
when the sectorial projections is in the calculus.


title: Discrete Koenigs nets and discrete isothermic surfaces

abstract:
  We discuss discretization of Koenigs nets (conjugate nets with equal Laplace
invariants) and of isothermic surfaces. Our discretization is based on the
notion of dual quadrilaterals: two planar quadrilaterals are called dual, if
their corresponding sides are parallel, and their non-corresponding diagonals
are parallel. Discrete Koenigs nets are defined as nets with planar
quadrilaterals admitting dual nets. Several novel geometric properties of
discrete Koenigs nets are found; in particular, two-dimensional discrete
Koenigs nets can be characterized by co-planarity of the intersection points of
diagonals of elementary quadrilaterals adjacent to any vertex; this
characterization is invariant with respect to projective transformations.
Discrete isothermic nets are defined as circular Koenigs nets. This is a new
geometric characterization of discrete isothermic surfaces introduced
previously as circular nets with factorized cross-ratios.


title:
The transition from highly to fully stretched polymer brushes in good
  solvent

abstract:
  The stretching of brushes of long polymers grafted to a planar surface is
investigated byMonte Carlo simulations in the limit of very high grafting
densities, as achieved in recent experiments. The monomer density profiles are
shown to deviate considerably from the parabolic limiting form predicted by
self-consistent field theory. A rapid transition is observed from parabolic to
fully stretched polymers, characterized by a dramatic change in the end-monomer
height distribution and by a clear cross-over in the slope of the brush height
versus scaled grafting density.


title:
Quantum Knizhnik-Zamolodchikov equation: reflecting boundary conditions
  and combinatorics

abstract:
  We consider the level 1 solution of quantum Knizhnik-Zamolodchikov equation
with reflecting boundary conditions which is relevant to the Temperley--Lieb
model of loops on a strip. By use of integral formulae we prove conjectures
relating it to the weighted enumeration of Cyclically Symmetric Transpose
Complement Plane Partitions and related combinatorial objects.


title:
Sure Wins, Separating Probabilities and the Representation of Linear
  Functionals

abstract:
  We discuss conditions under which a convex cone $\K\subset \R^{\Omega}$
admits a probability $m$ such that $\sup_{k\in \K} m(k)\leq0$. Based on these,
we also characterize linear functionals that admit the representation as
finitely additive expectations. A version of Riesz decomposition based on this
property is obtained as well as a characterisation of positive functionals on
the space of integrable functions


title: Characterization of quasi-coherent modules that are module schemes

abstract:
  The R-module functors that are essential for the development of the theory of
the linear representations of an affine R-group are the quasi-coherent
R-modules and the R-module schemes. The aim of this paper is to study when a
quasi-coherent R-module is an R-module scheme. We will prove that it is
equivalent to giving a characterization of projective R-modules of finite type.


title: Deconvolution for an atomic distribution

abstract:
  Let $X_1,...,X_n$ be i.i.d. observations, where $X_i=Y_i+\sigma Z_i$ and
$Y_i$ and $Z_i$ are independent. Assume that unobservable $Y$'s are distributed
as a random variable $UV,$ where $U$ and $V$ are independent, $U$ has a
Bernoulli distribution with probability of zero equal to $p$ and $V$ has a
distribution function $F$ with density $f.$ Furthermore, let the random
variables $Z_i$ have the standard normal distribution and let $\sigma>0.$ Based
on a sample $X_1,..., X_n,$ we consider the problem of estimation of the
density $f$ and the probability $p.$ We propose a kernel type deconvolution
estimator for $f$ and derive its asymptotic normality at a fixed point. A
consistent estimator for $p$ is given as well. Our results demonstrate that our
estimator behaves very much like the kernel type deconvolution estimator in the
classical deconvolution problem.


title: A normal distribution for the disturbance term in regression theory

abstract:
  In regression theory, it is stated that the disturbance term follows the
normal distribution when the sample size is large. In Professor J.Johnston's
words: "In view of the many factors involved, an appeal to the Central Limit
Theorem would further suggest a normal distribution for u." This paper includes
an elementary proof that the disturbance term follows the normal distribution
when n is large.


title: Towards a good definition of algebraically overtwisted

abstract:
  Symplectic field theory (SFT) is a collection of homology theories that
provide invariants for contact manifolds. We give a proof that vanishing of any
one of either contact homology, rational SFT or (full) SFT are equivalent. We
call a manifold for which these theories vanish "algebraically overtwisted".


title: G\'eom\'etrie, points entiers et courbes enti\`eres

abstract:
  Let $X$ be a projective variety over a number field $K$ (resp. over
$\mathbb{C}$). Let $H$ be the sum of ``sufficiently many positive divisors'' on
$X$. We show that any set of quasi-integral points (resp. any integral curve)
in $X-H$ is not Zariski dense.


title: The innermost region of the water megamaser radio galaxy 3C403

abstract:
  The standard unified scheme of active galactic nuclei requires the presence
of high column densities of gas and dust potentially obscuring the central
engine. So far, few direct subarcsecond resolution studies of this material
have been performed toward radio galaxies. The goal of this paper is to
elucidate the nuclear environment of the prototypical X-shaped Fanaroff-Riley
type II radio galaxy 3C403, the only powerful radio galaxy known to host a
water megamaser. Very Large Array A-array and single-dish Green Bank and
Effelsberg 1.3 cm measurements were performed to locate and monitor the water
maser emission. Very Long Baseline Interferometry 6 cm continuum observations
were taken to analyze the spatial structure of the nuclear environment at even
smaller scales, while the CO J=1-0 and 2-1 transitions were observed with the
IRAM 30-m telescope to search for thermal emission from a spatially extended,
moderately dense gas component.[abridged]


title: Spartan Random Processes in Time Series Modeling

abstract:
  A Spartan random process (SRP) is used to estimate the correlation structure
of time series and to predict (extrapolate) the data values. SRP's are
motivated from statistical physics, and they can be viewed as Ginzburg-Landau
models. The temporal correlations of the SRP are modeled in terms of
`interactions' between the field values. Model parameter inference employs the
computationally fast modified method of moments, which is based on matching
sample energy moments with the respective stochastic constraints. The
parameters thus inferred are then compared with those obtained by means of the
maximum likelihood method. The performance of the Spartan predictor (SP) is
investigated using real time series of the quarterly S&P 500 index. SP
prediction errors are compared with those of the Kolmogorov-Wiener predictor.
Two predictors, one of which explicit, are derived and used for extrapolation.
The performance of the predictors is similarly evaluated.


title:
Density modulo 1 of sublacunary sequences: application of Peres-Schlag's
  arguments

abstract:
  Let the sequence
  $\{t_n\}_{n=1}^{\infty}$ of reals satisfy the condition $ \frac{t_{n+1}}{t_n}
\ge 1+ \frac{\gamma}{n^\beta},0\le \beta <1, \gamma >0. $ Then the set $
\{\alpha \in [0,1]: \exists \varkappa > 0 \forall n \in \mathbb{N}
  ||t_n \alpha || > \frac{\varkappa}{n^\beta \log (n+1)} \} $ is uncountable.
Moreover its Hausdorff dimension is equal to 1.
  Consider the set of naturals of the form $2^n3^m$ and let the sequence $
s_1=1, s_2=2, s_3=3, s_4=4, s_5=6, s_6 = 8,... $ performs this set as an
increasing sequence. Then the set $ \{\alpha \in [0,1]: \exists \varkappa > 0
\forall n \in \mathbb{N}
  ||s_n \alpha || > \frac{\varkappa}{\sqrt{n}\log (n+1)} \} $ also has
Hausdorff dimension equal to 1. The results obtained use an original approach
due to Y. Peres and W. Schlag.


title: Co-Betweenness: A Pairwise Notion of Centrality

abstract:
  Betweenness centrality is a metric that seeks to quantify a sense of the
importance of a vertex in a network graph in terms of its "control" on the
distribution of information along geodesic paths throughout that network. This
quantity however does not capture how different vertices participate together
in such control. In order to allow for the uncovering of finer details in this
regard, we introduce here an extension of betweenness centrality to pairs of
vertices, which we term co-betweenness, that provides the basis for quantifying
various analogous pairwise notions of importance and control. More
specifically, we motivate and define a precise notion of co-betweenness, we
present an efficient algorithm for its computation, extending the algorithm of
Brandes in a natural manner, and we illustrate the utilization of this
co-betweenness on a handful of different communication networks. From these
real-world examples, we show that the co-betweenness allows one to identify
certain vertices which are not the most central vertices but which,
nevertheless, act as important actors in the relaying and dispatching of
information in the network.


title: Elaborations on the String Dual to N=1 SQCD

abstract:
  In this paper we make further refinements to the duality proposed between N=1
SQCD and certain string (supergravity plus branes) backgrounds, working in the
regime of comparable large number of colors and flavors. Using the string
theory solutions, we predict different field theory observables and phenomena
like Seiberg duality, gauge coupling and its running, the behavior of Wilson
and 't Hooft loops, anomalous dimensions of the quark superfields, quartic
superpotential coupling and its running, continuous and discrete anomaly
matching. We also give evidence for the smooth interpolation between higgsed
and confining vacua. We provide several matchings between field theory and
string theory computations.


title:
Constraining Newtonian stellar configurations in f(R) theories of
  gravity

abstract:
  We consider general metric $f(R)$ theories of gravity by solving the field
equations in the presence of a spherical static mass distribution by analytical
perturbative means. Expanding the field equations systematically in $\cO(G)$,
we solve the resulting set of equations and show that $f(R)$ theories which
attempt to solve the dark energy problem very generally lead to
$\gamma_{PPN}=1/2$ in the solar system. This excludes a large class of theories
as possible explanations of dark energy. We also present the first order
correction to $\gamma_{PPN}$ and show that it cannot have a significant effect.


title: Molecular properties of (U)LIRGs: CO, HCN, HNC and HCO+

abstract:
  The observed molecular properties of a sample of FIR-luminous and OH
megamaser (OH-MM) galaxies have been investigated. The ratio of high and
low-density tracer lines is found to be determined by the progression of the
star formation in the system. The HCO+/HCN and HCO+/HNC line ratios are good
proxies for the density of the gas, and PDR and XDR sources can be
distinguished using the HNC/HCN line ratio. The properties of the OH-MM sources
in the sample can be explained by PDR chemistry in gas with densities higher
than 10^5.5 cm^-3, confirming the classical OH-MM model of IR pumped
amplification with (variable) low gains.


title: Lattice exciton-polaron problem by quantum Monte Carlo simulations

abstract:
  Exciton-polaron formation in one-dimensional lattice models with short or
long-range carrier-phonon interaction is studied by quantum Monte Carlo
simulations. Depending on the relative sign of electron and hole-phonon
coupling, the exciton-polaron size increases or decreases with increasing
interaction strength. Quantum phonon fluctuations determine the
(exciton-)polaron size and yield translation-invariant states at all finite
couplings.


title: The complexity of the envelope of line and plane arrangements

abstract:
  A facet of an hyperplane arrangement is called external if it belongs to
exactly one bounded cell. The set of all external facets forms the envelope of
the arrangement. The number of external facets of a simple arrangement defined
by $n$ hyperplanes in dimension $d$ is hypothesized to be at least $d{n-2
\choose d-1}$. In this note we show that, for simple arrangements of 4 lines or
more, the minimum number of external facets is equal to $2(n-1)$, and for
simple arrangements of 5 planes or more, the minimum number of external facets
is between $\frac{n(n-2)+6}{3}$ and $(n-4)(2n-3)+5$.


title: Raman imaging and electronic properties of graphene

abstract:
  Graphite is a well-studied material with known electronic and optical
properties. Graphene, on the other hand, which is just one layer of carbon
atoms arranged in a hexagonal lattice, has been studied theoretically for quite
some time but has only recently become accessible for experiments. Here we
demonstrate how single- and multi-layer graphene can be unambiguously
identified using Raman scattering. Furthermore, we use a scanning Raman set-up
to image few-layer graphene flakes of various heights. In transport experiments
we measure weak localization and conductance fluctuations in a graphene flake
of about 7 monolayer thickness. We obtain a phase-coherence length of about 2
$\mu$m at a temperature of 2 K. Furthermore we investigate the conductivity
through single-layer graphene flakes and the tuning of electron and hole
densities via a back gate.


title:
Mutual information for the selection of relevant variables in
  spectrometric nonlinear modelling

abstract:
  Data from spectrophotometers form vectors of a large number of exploitable
variables. Building quantitative models using these variables most often
requires using a smaller set of variables than the initial one. Indeed, a too
large number of input variables to a model results in a too large number of
parameters, leading to overfitting and poor generalization abilities. In this
paper, we suggest the use of the mutual information measure to select variables
from the initial set. The mutual information measures the information content
in input variables with respect to the model output, without making any
assumption on the model that will be used; it is thus suitable for nonlinear
modelling. In addition, it leads to the selection of variables among the
initial set, and not to linear or nonlinear combinations of them. Without
decreasing the model performances compared to other variable projection
methods, it allows therefore a greater interpretability of the results.


title: Bulk antisymmetric tensor fields in a Randall-Sundrum model

abstract:
  We consider bulk antisymmetric tensor fields of various ranks in a
Randall-Sundrum scenario. We show that, rank-2 onwards, the zero-modes of the
projections of these fields on the (3+1) dimensional visible brane become
increasingly weaker as the rank of the tensor increases. All such tensor fields
of rank 4 or more are absent from the dynamics in four dimensions. This leaves
only the zero-mode graviton to have coupling $\sim 1/M_P$ with matter, thus
explaining why the large-scale behaviour of the universe is governed by gravity
only. We have also computed the masses of the heavier modes upto rank-3, and
shown that they are relatively less likely to have detectable accelerator
signals.


title:
Weak and strong coupling limits of the two-dimensional Fr\"ohlich
  polaron with spin-orbit Rashba interaction

abstract:
  The continuous progress in fabricating low-dimensional systems with large
spin-orbit couplings has reached a point in which nowadays materials may
display spin-orbit splitting energies ranging from a few to hundreds of meV.
This situation calls for a better understanding of the interplay between the
spin-orbit coupling and other interactions ubiquitously present in solids, in
particular when the spin-orbit splitting is comparable in magnitude with
characteristic energy scales such as the Fermi energy and the phonon frequency.
  In this article, the two-dimensional Fr\"ohlich electron-phonon problem is
reformulated by introducing the coupling to a spin-orbit Rashba potential,
allowing for a description of the spin-orbit effects on the electron-phonon
interaction. The ground state of the resulting Fr\"ohlich-Rashba polaron is
studied in the weak and strong coupling limits of the electron-phonon
interaction for arbitrary values of the spin-orbit splitting. The weak coupling
case is studied within the Rayleigh-Schr\"odinger perturbation theory, while
the strong-coupling electron-phonon regime is investigated by means of
variational polaron wave functions in the adiabatic limit. It is found that,
for both weak and strong coupling polarons, the ground state energy is
systematically lowered by the spin-orbit interaction, indicating that the
polaronic character is strengthened by the Rashba coupling. It is also shown
that, consistently with the lowering of the ground state, the polaron effective
mass is enhanced compared to the zero spin-orbit limit. Finally, it is argued
that the crossover between weakly and strongly coupled polarons can be shifted
by the spin-orbit interaction.


title: The irradiated ISM of ULIRGs

abstract:
  The nuclei of ULIRGs harbor massive young stars, an accreting central black
hole, or both. Results are presented for molecular gas that is exposed to
X-rays (1-100 keV, XDRs) and far-ultraviolet radiation (6-13.6 eV, PDRs).
Attention is paid to species like HCO+, HCN, HNC, OH, H2O and CO. Line ratios
of HCN/HCO+ and HNC/HCN discriminate between PDRs and XDRs. Very high J (>10)
CO lines, observable with HIFI/Herschel, discriminate very well between XDRs
and PDRs. In XDRs, it is easy to produce large abundances of warm (T>100 K) H2O
and OH. In PDRs, only OH is produced similarly well.


title: K-Scaffold subgraphs of Complex networks

abstract:
  Complex networks with high numbers of nodes or links are often difficult to
analyse. However, not all elements contribute equally to their structural
patterns. A small number of elements (the hubs) seem to play a particularly
relevant role in organizing the overall structure around them. But other parts
of the architecture (such as hub-hub connecting elements) are also important.
In this letter we present a new type of substructure, to be named the
$K$-scaffold subgraph, able to capture all the essential network components.
Their key features, including the so called critical scaffold graph, are
analytically derived.


title:
Bifurcation From Networks of Unstable Attractors to Heteroclinic
  Switching

abstract:
  We present a dynamical system that naturally exhibits two unstable attractors
that are completely enclosed by each others basin volume. This
counter-intuitive phenomenon occurs in networks of pulse-coupled oscillators
with delayed interactions. We analytically and numerically investigate this
phenomenon and clarify the mechanism underlying it: Upon continuously removing
the non-invertibility of the system, the set of two unstable attractors becomes
a set of two non-attracting saddle states that are heteroclinically connected
to each other. This transition from a network of unstable attractors to a
heteroclinic cycle constitutes a new type of bifurcation in dynamical systems.

categories: nlin.CD cond-mat.dis-nn nlin.AO q-bio.NC


title:
Attempted density blowup in a freely cooling dilute granular gas:
  hydrodynamics versus molecular dynamics

abstract:
  It has been recently shown (Fouxon et al. 2007) that, in the framework of
ideal granular hydrodynamics (IGHD), an initially smooth hydrodynamic flow of a
granular gas can produce an infinite gas density in a finite time. Exact
solutions that exhibit this property have been derived. Close to the
singularity, the granular gas pressure is finite and almost constant. This work
reports molecular dynamics (MD) simulations of a freely cooling gas of nearly
elastically colliding hard disks, aimed at identifying the "attempted" density
blowup regime. The initial conditions of the simulated flow mimic those of one
particular solution of the IGHD equations that exhibits the density blowup. We
measure the hydrodynamic fields in the MD simulations and compare them with
predictions from the ideal theory. We find a remarkable quantitative agreement
between the two over an extended time interval, proving the existence of the
attempted blowup regime. As the attempted singularity is approached, the
hydrodynamic fields, as observed in the MD simulations, deviate from the
predictions of the ideal solution. To investigate the mechanism of breakdown of
the ideal theory near the singularity, we extend the hydrodynamic theory by
accounting separately for the gradient-dependent transport and for finite
density corrections.


title: Phase Transitions and the Perfectness of Fluids

abstract:
  We calculate the ratio eta/s, the shear viscosity (eta) to entropy density
(s), which characterizes how perfect a fluid is, in weakly coupled real scalar
field theories with different types of phase transitions. The mean-field
results of the eta/s behaviors agree with the empirical observations in atomic
and molecular systems such as water, He, N, and all the matters with data
available in the NIST database. These behaviors are expected to be the same in
N component scalar theories with an O(N) symmetry. We speculate these eta/s
behaviors are general properties of fluid shared by QCD and cold atoms.
Finally, we clarify some issues regarding counterexamples of the conjectured
universal eta/s bound found in Refs.[16,17].

categories: hep-ph cond-mat.other cond-mat.soft hep-lat nucl-ex nucl-th


title:
Lepton flavor violating $\mu\to e\gamma$ and $\mu-e$ conversion in
  unparticle physics

abstract:
  We have studied lepton flavor violation processes $\mu\to e\gamma$ and
$\mu-e$ conversion in nuclei induced by unparticle. Both ${\rm Br}(\mu\to
e\gamma)$ and $\mu-e$ conversion rate ${\rm CR}(\mu-e,{\rm Nuclei})$ strongly
depend on the scale dimension $d_{\cal U}$ and the unparticle coupling
$\lambda^{ff'}_{\rm K}$(K=V, A, S, P). Present experimental upper bounds on
${\rm Br}(\mu\to e\gamma)$, ${\rm CR}(\mu-e,{\rm Ti})$ and ${\rm CR}(\mu-e,{\rm
Au})$ put stringent constraints on the parameters of unaprticle physics. The
scale dimensions $d_{\cal U}$ around 2 are favored for the unparticle scale
$\Lambda_{\cal U}$ of ${\cal O}(10 {\rm TeV})$ and the unparticle coupling of
${\cal O}(10^{-3})$. ${\rm CR}(\mu-e,{\rm Nuclei})$ is proportional to
$\rm{Z^4_{eff}A^2/Z}$ for the pure vector and scalar couplings between
unparticle and SM fermions, this peculiar atomatic number dependence can be
used to distinguish unparticle from other theoretical models.


title: Higher Homotopy Hopf Algebras Found: A Ten Year Retrospective

abstract:
  The search for higher homotopy Hopf algebras (known today as
A_\infty-bialgebras) began in 1996 during a conference at Vassar College
honoring Jim Stasheff in the year of his 60th birthday. In a talk entitled "In
Search of Higher Homotopy Hopf Algebras", I indicated that a DG Hopf algebra
could be thought of as some (unknown) higher homotopy structure with trivial
higher order structure and deformed using a graded version of Gerstenhaber and
Schack's bialgebra deformation theory. In retrospect, the bi(co)module
structure encoded in Gerstenhaber and Schack's differential defining
deformation cohomology detects some (but not all) of the A_infty-bialgebra
structure relations. Nevertheless, this motivated the discovery of
A_infty-bialgebras by S. Saneblidze and myself in 2005.


title:
Azimuthal distinguishability of entangled photons generated in
  spontaneous parametric down-conversion

abstract:
  We experimentally demonstrate that paired photons generated in different
sections of a down-conversion cone, when some of the interacting waves show
Poynting vector walk-off, carry different spatial correlations, and therefore a
different degree of spatial entanglement. This is shown to be in agreement with
theoretical results. We also discuss how this azimuthal distinguishing
information of the down-conversion cone is relevant for the implementation of
quantum sources aimed at the generation of entanglement in other degrees of
freedom, such as polarization.


title: High Energy Neutrinos with a Mediterranean Neutrino Telescope

abstract:
  The high energy neutrino detection by a km^3 Neutrino Telescope placed in the
Mediterranean sea provides a unique tool to both determine the diffuse
astrophysical neutrino flux and the neutrino-nucleon cross section in the
extreme kinematical region, which could unveil the presence of new physics.
Here is performed a brief analysis of possible NEMO site performances.


title:
Multiple minor mergers: formation of elliptical galaxies and constraints
  for the growth of spiral disks

abstract:
  Multiple, sequential mergers are unavoidable in the hierarchical build-up
picture of galaxies, in particular for the minor mergers that are frequent and
highly likely to have occured several times for most present-day galaxies.
However, the effect of repeated minor mergers on galactic structure and
evolution has not been studied systematically so far. We present a numerical
study of multiple, subsequent, minor galaxy mergers, with various mass ratios
ranging from 4:1 to 50:1. The N-body simulations include gas dynamics and star
formation. We study the morphological and kinematical properties of the
remnants, and show that several so-called "minor" mergers can lead to the
formation of elliptical-like galaxies that have global morphological and
kinematical properties similar to that observed in real elliptical galaxies.
The properties of these systems are compared with those of elliptical galaxies
produced by the standard scenario of one single major merger. We thus show that
repeated minor mergers can theoretically form elliptical galaxies without major
mergers, and can be more frequent than major mergers, in particular at moderate
redshift. This process must then have formed some elliptical galaxies seen
today, and could in particular explain the high boxiness of massive
ellipticals, and some fundamental relations observed in ellipticals. In
addition, because repeated minor mergers, even at high mass ratios, destroy
disks into spheroids, these results indicate that spiral galaxies cannot have
grown only by a succession of minor mergers.


title:
New target transverse spin dependent azimuthal asymmetries from COMPASS
  experiment

abstract:
  In general, eight target transverse spin-dependent azimuthal modulations are
allowed in semi inclusive deep inelastic scattering of polarized leptons on a
transversely polarized target. In the QCD parton model four of these
asymmetries can be interpreted within the leading order approach. Two of them,
namely Collins and Sivers effects were already measured by HERMES and COMPASS
experiments. Other two leading twist and remaining four azimuthal asymmetries
which can be interpreted as twist-three contributions have been measured for
the first time in COMPASS using a 160 GeV/c longitudinally polarized
($P_{beam}\simeq -0.8$) muon beam and a transversely polarized $^6LiD$ target.
We present here the preliminary results from the 2002-2004 data.


title: Arp 220 - IC 4553/4: understanding the system and diagnosing the ISM

abstract:
  Arp220 is a nearby system in final stages of galaxy merger with powerful
ongoing star-formation at and surrounding the two nuclei. Arp 220 was detected
in HI absorption and OH Megamaser emission and later recognized as the nearest
ultra-luminous infrared galaxy also showing powerful molecular and X-ray
emissions. In this paper we review the available radio and mm-wave
observational data of Arp 220 in order to obtain an integrated picture of the
dense interstellar medium that forms the location of the powerful
star-formation at the two nuclei.


title: Sensitivity and Insensitivity of Galaxy Cluster Surveys to New Physics

abstract:
  We study the implications and limitations of galaxy cluster surveys for
constraining models of particle physics and gravity beyond the Standard Model.
Flux limited cluster counts probe the history of large scale structure
formation in the universe, and as such provide useful constraints on
cosmological parameters. As a result of uncertainties in some aspects of
cluster dynamics, cluster surveys are currently more useful for analyzing
physics that would affect the formation of structure than physics that would
modify the appearance of clusters. As an example we consider the Lambda-CDM
cosmology and dimming mechanisms, such as photon-axion mixing.


title: On the steady compressible Navier-Stokes-Fourier system

abstract:
  We study the motion of the steady compressible heat conducting viscous fluid
in a bounded three dimensional domain governed by the compressible
Navier-Stokes-Fourier system. Our main result is the existence of a weak
solution to these equations for arbitrarily large data. A key element of the
proof is a special approximation of the original system guaranteeing pointwise
uniform boundedness of the density. Therefore the passage to the limit omits
tedious technical tricks required by the standard theory. Basic estimates on
the solutions are possible to obtain by a suitable choice of physically
reasonable boundary conditions.


title: On period spaces for p-divisible groups

abstract:
  In their book Rapoport and Zink constructed rigid analytic period spaces for
Fontaine's filtered isocrystals, and period morphisms from moduli spaces of
p-divisible groups to some of these period spaces. We determine the image of
these period morphisms, thereby contributing to a question of Grothendieck. We
give examples showing that only in rare cases the image is all of the
Rapoport-Zink period space.


title: Opportunities for maser studies with the Square Kilometre Array

abstract:
  The Square Kilometre Array (SKA) is the radio telescope of the next
generation, providing an increase in sensitivity and angular resolution of two
orders of magnitude over existing telescopes. Currently, the SKA is expected to
span the frequency range 0.1-25 GHz with capabilities including a wide
field-of-view and measurement of polarised emission. Such a telescope has
enormous potential for testing fundamental physical laws and producing
transformational discoveries. Important science goals include using H2O
megamasers to make precise estimates of H0, which will anchor the extragalactic
distance scale, and to probe the central structures of accretion disks around
supermassive black holes in AGNs, to study OH megamasers associated with
extreme starburst activity in distant galaxies and to study with unprecedented
precision molecular gas and star formation in our Galaxy.


title: The integrals in Gradshteyn and Ryzhik. Part 10: the digamma function

abstract:
  Many integrals in the classical table by Gradshteyn and Ryzhik can be
evaluated in terms of the digamma function (= the logarithmic derivative of the
gamma function). Some of them are presented here.


title: Hodge cohomology of invertible sheaves

abstract:
  v2: We improved a little bit according to the referee's wishes.
  v1: On $X$ projective smooth over a field $k$, Pink and Roessler conjecture
that the dimension of the Hodge cohomology of an invertible $n$-torsion sheaf
$L$ is the same as the one of its $a$-th power $L^a$ if $a$ is prime to $n$,
under the assumptions that $X$ lifts to $W_2(k)$ and $dim X\le p$, if $k$ has
characteristic $p>0$. They show this if $k$ has characteristic 0 and if $n$ is
prime to $p$ in characteristic $p>0$. We show the conjecture in characteristic
$p>0$ if $n=p$ assuming in addition that $X$ is ordinary (in the sense of
Bloch-Kato).


title: On the auxiliary particle filter

abstract:
  In this article we study asymptotic properties of weighted samples produced
by the auxiliary particle filter (APF) proposed by pitt and shephard (1999).
Besides establishing a central limit theorem (CLT) for smoothed particle
estimates, we also derive bounds on the Lp error and bias of the same for a
finite particle sample size. By examining the recursive formula for the
asymptotic variance of the CLT we identify first-stage importance weights for
which the increase of asymptotic variance at a single iteration of the
algorithm is minimal. In the light of these findings, we discuss and
demonstrate on several examples how the APF algorithm can be improved.


title:
Blind Signal Separation Methods for the Identification of Interstellar
  Carbonaceous Nanoparticles

abstract:
  The use of Blind Signal Separation methods (ICA and other approaches) for the
analysis of astrophysical data remains quite unexplored. In this paper, we
present a new approach for analyzing the infrared emission spectra of
interstellar dust, obtained with NASA's Spitzer Space Telescope, using FastICA
and Non-negative Matrix Factorization (NMF). Using these two methods, we were
able to unveil the source spectra of three different types of carbonaceous
nanoparticles present in interstellar space. These spectra can then constitute
a basis for the interpretation of the mid-infrared emission spectra of
interstellar dust in the Milky Way and nearby galaxies. We also show how to use
these extracted spectra to derive the spatial distribution of these
nanoparticles.