title:
A re-visit of the phase-resolved X-ray and \gamma-ray spectra of the
  Crab pulsar

abstract:
  We use a modified outer gap model to study the multi-frequency phase-resolved
spectra of the Crab pulsar. The emissions from both poles contribute to the
light curve and the phase-resolved spectra. Using the synchrotron self-Compton
mechanism and by considering the incomplete conversion of curvature photons
into secondary pairs, the observed phase-averaged spectrum from 100 eV - 10 GeV
can be explained very well. The predicted phase-resolved spectra can match the
observed data reasonably well, too. We find that the emission from the north
pole mainly contributes to Leading Wing 1. The emissions in the remaining
phases are mainly dominated by the south pole. The widening of the azimuthal
extension of the outer gap explains Trailing Wing 2. The complicated
phase-resolved spectra for the phases between the two peaks, namely Trailing
Wing 1, Bridge and Leading Wing 2, strongly suggest that there are at least two
well-separated emission regions with multiple emission mechanisms, i.e.
synchrotron radiation, inverse Compton scattering and curvature radiation. Our
best fit results indicate that there may exist some asymmetry between the south
and the north poles. Our model predictions can be examined by GLAST.


title:
Magnification Probability Distribution Functions of Standard Candles in
  a Clumpy Universe

abstract:
  Lensing effects on light rays from point light sources, such like Type Ia
supernovae, are simulated in a clumpy universe model. In our universe model, it
is assumed that all matter in the universe takes the form of randomly
distributed objects each of which has finite size and is transparent for light
rays. Monte-Carlo simulations are performed for several lens models, and we
compute probability distribution functions of magnification. In the case of the
lens models that have a smooth density profile or the same degree of density
concentration as the spherical NFW (Navarro-Frenk-White) lens model at the
center, the so-called gamma distributions fit well the magnification
probability distribution functions if the size of lenses is sufficiently larger
than the Einstein radius. In contrast, the gamma distributions do not fit the
magnification probability distribution functions in the case of the SIS
(Singular Isothermal Sphere) lens model. We find, by using the power law cusp
model, that the magnification probability distribution function is fitted well
using the gamma distribution only when the slope of the central density profile
is not very steep. These results suggest that we may obtain information about
the slope of the central density profiles of dark matter halo from the lensing
effect of Type Ia supernovae.


title:
Energy-Momentum Distribution of the Weyl-Lewis-Papapetrou and the
  Levi-Civita Metrics

abstract:
  This paper is devoted to compute the energy-momentum densities for two exact
solutions of the Einstein field equations by using the prescriptions of
Einstein, Landau-Lifshitz, Papapetrou and M\"{o}ller. The spacetimes under
consideration are the Weyl-Lewis-Papapetrou and the Levi-Civita metrics. The
Weyl metric becomes the special case of the Weyl-Lewis-Papapetrou solution. The
Levi-Civita metric provides constant momentum in each prescription with
different energy density. The Weyl-Lewis-Papapetrou metric yields all the
quantities different in each prescription. These differences support the
well-defined proposal developed by Cooperstock and from the energy-momentum
tensor itself.


title:
The largest sample eigenvalue distribution in the rank 1 quaternionic
  spiked model of Wishart ensemble

abstract:
  We solve the largest sample eigenvalue distribution problem in the rank 1
spiked model of the quaternionic Wishart ensemble, which is the first case of a
statistical generalization of the Laguerre symplectic ensemble (LSE) on the
soft edge. We observe a phase change phenomenon similar to that in the complex
case, and prove that the new distribution at the phase change point is the GOE
Tracy--Widom distribution.


title:
Assortative mixing in Protein Contact Networks and protein folding
  kinetics

abstract:
  Starting from linear chains of amino acids, the spontaneous folding of
proteins into their elaborate three-dimensional structures is one of the
remarkable examples of biological self-organization. We investigated native
state structures of 30 single-domain, two-state proteins, from complex networks
perspective, to understand the role of topological parameters in proteins'
folding kinetics, at two length scales-- as ``Protein Contact Networks (PCNs)''
and their corresponding ``Long-range Interaction Networks (LINs)'' constructed
by ignoring the short-range interactions. Our results show that, both PCNs and
LINs exhibit the exceptional topological property of ``assortative mixing''
that is absent in all other biological and technological networks studied so
far. We show that the degree distribution of these contact networks is partly
responsible for the observed assortativity. The coefficient of assortativity
also shows a positive correlation with the rate of protein folding at both
short and long contact scale, whereas, the clustering coefficients of only the
LINs exhibit a negative correlation. The results indicate that the general
topological parameters of these naturally-evolved protein networks can
effectively represent the structural and functional properties required for
fast information transfer among the residues facilitating biochemical/kinetic
functions, such as, allostery, stability, and the rate of folding.


title:
In search of the QCD odderon in exclusive J/psi and Upsilon
  hadroproduction

abstract:
  Phenomenological studies of odderon effects are shortly reviewed. Special
emphasis is devoted to a recent study of the exclusive production of J/psi or
Upsilon in pp and bar p p collisions, where the meson emerges from the
pomeron--odderon and the pomeron--photon fusion.


title:
Edge states and the integer quantum Hall conductance in spin-chiral
  ferromagnetic kagome lattice

abstract:
  We investigate the chiral edge states in the two-dimensional ferromagntic
kagom\'{e} lattice with spin anisotropies included. The system is periodic in
the $x$ direction but has two edges in the $y$ direction. The Harper equation
for solving the energies of edge states is derived. We find that there are two
edge states in each bulk energy gap, corresponding to two zero points of the
Bloch function on the complex-energy Riemann surface (RS). The edge-state
energy loops parametrized by the momentum $k_{x}$ cross the holes of the RS.
When the Fermi energy lies in the bulk energy gap, the quantized Hall
conductance is given by the winding number of the edge states across the holes,
which reads as $\sigma_{xy}^{\text{edge}}$=$-\frac{e^{2}}{h}% $sgn$(\sin\phi)
$, where $\phi$ is the spin chiral parameter (see text). This result keeps
consistent with that based on the topological bulk theory.


title:
Calculation of the potential of mean force from nonequilibrium
  measurements via maximum likelihood estimators

abstract:
  We present an approach to the estimate of the potential of mean force along a
generic reaction coordinate based on maximum likelihood methods and
path-ensemble averages in systems driven far from equilibrium. Following
similar arguments, various free energy estimators can be recovered, all
providing comparable computational accuracy. The method, applied to the
unfolding process of the alpha-helix form of an alanine deca-peptide, gives
results in good agreement with thermodynamic integration.


title: SO(10) GUT Baryogenesis

abstract:
  Baryogenesis, through the decays of heavy bosons, was considered to be one of
the major successes of the grand unified theories (GUTs). It was then realized
that the sphaleron processes erased any baryon asymmetry from the
GUT-baryogenesis at a later stage. In this paper, we discuss the idea of
resurrecting GUT-baryogenesis in a large class of SO(10) GUTs. Our analysis
shows that fast lepton number violating but baryon number conserving processes
can partially wash out the GUT-baryogenesis produced lepton and/or baryon
asymmetry associated with or without the sphaleron and/or Yukawa interactions.


title: Left-Right Symmetric Model of Neutrino Dark Energy

abstract:
  We implemented the neutrino dark energy proposal in a left-right symmetric
model. Unlike earlier models of mass varying neutrinos, in the present model
the mass parameter that depends on the scalar field (acceleron) remains very
light naturally. The required neutrino masses then predicts the U(1)_R breaking
scale to be in the TeV range, providing new signals for LHC. Compared to all
other neutrino dark energy proposals, this model has the added advantage that
it can also be embedded into a grand unified theory. In this scenario
leptogenesis occurs through decays of scalars at very high energy.


title:
Estimating Granger causality from Fourier and wavelet transforms of time
  series data

abstract:
  Experiments in many fields of science and engineering yield data in the form
of time series. The Fourier and wavelet transform-based nonparametric methods
are used widely to study the spectral characteristics of these time series
data. Here, we extend the framework of nonparametric spectral methods to
include the estimation of Granger causality spectra for assessing directional
influences. We illustrate the utility of the proposed methods using synthetic
data from network models consisting of interacting dynamical systems.

categories: physics.data-an cond-mat.stat-mech physics.bio-ph physics.geo-ph


title:
Effects of feedback and feedforward loops on dynamics of transcriptional
  regulatory model networks

abstract:
  We demonstrate the advantages of feedforward loops using a Boolean network,
which is one of the discrete dynamical models for transcriptional regulatory
networks. After comparing the dynamical behaviors of network embedded feedback
and feedforward loops, we found that feedforward loops can provide higher
temporal order (coherence) with lower entropy (randomness) in a temporal
program of gene expression. In addition, complexity of the state space that
increases with longer length of attractors and greater number of attractors is
also reduced for networks with more feedforward loops. Feedback loops show
opposite effects on dynamics of the networks. These results suggest that
feedforward loops are one of the favorable local structures in biomolecular and
neuronal networks.


title:
Leading two-loop Yukawa corrections to the pole masses of SUSY fermions
  in the MSSM

abstract:
  We have calculated the leading Yukawa corrections to the chargino, neutralino
and gluino pole masses in the DR-bar scheme in the Minimal Supersymmetric
Standard Model (MSSM) with the full set of complex parameters. We have
performed a numerical analysis for a particular point in the parameter space
and found typical corrections of a few tenths of a percent thus exceeding the
experimental resolution as expected at the ILC. We provide a computer program
which calculates two-loop pole masses for SUSY fermions with complex parameters
up to the respective order in pertubation theory.


title:
The angle of repose of spherical grains in granular Hele-Shaw cells: A
  molecular dynamics study

abstract:
  We report the results of three dimensional molecular dynamic simulations on
the angle of repose of a sandpile formed by pouring mono-sized cohesionless
spherical grains into a granular Hele-Shaw cell. In particular, we are
interested to investigate the effects of those variables which may impact
significantly on pattern formation of granular mixtures in Hele-Shaw cells. The
results indicate that the frictional forces influence remarkably the formation
of pile on the grain level. Furthermore, We see that increasing grain insertion
rate decreases slightly the angle of repose. We also find that in accordance
with experimental results, the cell thickness is another significant factor and
the angle of repose decays exponentially by increasing the cell thickness. It
is shown that this effect can be interpreted as a cross-over from two to three
dimensions. In fact, using grains with different sizes shows that the behaviour
of the angle of repose when both size and cell thickness are varied is
controlled by a scaled function of the ratio of these two variables.


title: Electrically driven spin excitation in a ferroelectric magnet DyMnO_3

abstract:
  Temperature (5--250 K) and magnetic field (0--70 kOe) variations of the
low-energy (1--10 meV) electrodynamics of spin excitations have been
investigated for a complete set of light-polarization configurations for a
ferroelectric magnet DyMnO$_3$ by using terahertz time-domain spectroscopy. We
identify the pronounced absorption continuum (1--8 meV) with a peak feature
around 2 meV, which is electric-dipole active only for the light $E$-vector
along the a-axis. This absorption band grows in intensity with lowering
temperature from the spin-collinear paraelectric phase above the ferroelectric
transition, but is independent of the orientation of spiral spin plane ($bc$ or
$ab$), as shown on the original $P_{\rm s}$ (ferroelectric polarization)
$\parallel c$ phase as well as the magnetic field induced $P_{\rm s}\parallel
a$ phase. The possible origin of this electric-dipole active band is argued in
terms of the large fluctuations of spins and spin-current.


title: Free Martingale polynomials for stationary Jacobi processes

abstract:
  We generalize a previous result concerning free martingale polynomials for
the stationary free Jacobi process of parameters $\lambda \in ]0.1], \theta =
1/2$. Hopelessly, apart from the case $\lambda = 1$, the polynomials we derive
are no longer orthogonal with respect to the spectral measure. As a matter of
fact, we use the multiplicative renormalization to write down the corresponding
orthogonality measure.


title: On the dimension of the sheets of a reductive Lie algebra

abstract:
  This note is a corrigendum to the previous version arXiv:0711.2735v3
published in J. Lie Theory. As it has been recently pointed out to me by
Alexander Premet, Remark 3 of arXiv:0711.2735v3 is incorrect. We verify in this
note thanks to recent results of Premet and Topley (see arXiv:1301.4653) that
Theorem 25 of arXiv:0711.2735v3 remains correct in spite of this error.


title: Knitted Complex Networks

abstract:
  To a considerable extent, the continuing importance and popularity of complex
networks as models of real-world structures has been motivated by scale free
degree distributions as well as the respectively implied hubs. Being related to
sequential connections of edges in networks, paths represent another important,
dual pattern of connectivity (or motif) in complex networks (e.g., paths are
related to important concepts such as betweeness centrality). The present work
proposes a new supercategory of complex networks which are organized and/or
constructed in terms of paths. Two specific network classes are proposed and
characterized: (i) PA networks, obtained by star-path transforming
Barabasi-Albert networks; and (ii) PN networks, built by performing progressive
paths involving all nodes without repetition. Such new networks are important
not only from their potential to provide theoretical insights, but also as
putative models of real-world structures. The connectivity structure of these
two models is investigated comparatively to four traditional complex networks
models (Erdos-Renyi, Barabasi-Albert, Watts-Strogatz and a geographical model).
A series of interesting results are described, including the corroboration of
the distinct nature of the two proposed models and the importance of
considering a comprehensive set of measurements and multivariated statistical
methods for the characterization of complex networks.


title:
Invarianten zusammenh\"angender Gruppen und die Cohen-Macaulay
  Eigenschaft

abstract:
  For G=SL_n or GL_n we construct representations V such that the invariant
ring K[V]^G is not Cohen-Macaulay.


title: Konstruktion von Invariantenringen ohne die Cohen-Macaulay Eigenschaft

abstract: We give examples of Non-Cohen-Macaulay invariant rings.


title: Asymptotic cohomology of circular units

abstract:
  Let $F$ be a number field, abelian over the rational field, and fix a odd
prime number $p$. Consider the cyclotomic $Z_p$-extension $F_\infty/F$ and
denote $F_n$ the ${n}^{\rm th}$ finite subfield and $C_n$ its group of circular
units. Then the Galois groups $G_{m,n}=\Gal(F_m/F_n)$ act naturally on the
$C_m$'s (for any $m\geq n>> 0$). We compute the Tate cohomology groups
$\Hha^i(G_{m,n}, C_m)$ for $i=-1,0$ without assuming anything else neither on
$F$ nor on $p$.


title: Diffractive structure function F_L^D from fits with higher twist

abstract:
  We make predictions for the diffractive longitudinal structure function F_L^D
to be measured at HERA, based on DGLAP fits of diffractive parton distributions
with twist--4 contribution. This contribution describes diffractive qqbar
production from longitudinal photons and significantly changes predictions for
F_L^D obtained in pure DGLAP analyses.


title:
The Fine-Tuning Price of Neutralino Dark Matter in Models with
  Non-Universal Higgs Masses

abstract:
  We study the amounts of fine-tuning of the parameters of the MSSM with
non-universal soft supersymmetry-breaking contributions to the Higgs masses
(the NUHM) that would be required for the relic neutralino density to lie
within the range favoured by WMAP and other astrophysical and cosmological
observations. Such dark matter fine-tuning is analogous to the commonly studied
electroweak fine-tuning associated with satisfying the electroweak symmetry
breaking conditions, which we also study for completeness. We identify several
distinct regions of the NUHM parameter space: a bulk region, a $\stau-\neut$
coannihilation region, a pseudoscalar Higgs funnel region, a focus-point
bino/higgsino region and a $\sneut-\neut$ coannihilation region. Within each
region, we analyse specific representative points for which we provide
breakdowns of the contributions to the dark matter fine-tuning associated with
the different NUHM parameters. In general, the NUHM offers points with both
both smaller and larger amounts of dark matter fine-tuning than points in the
corresponding regions of the CMSSM. Lower amounts of dark matter fine-tuning
typically arise at points where several different (co)annihilation processes
contribute, e.g., at junctions between regions with different dominant
processes. We comment on the prospects for using collider measurements to
estimate the likely dark matter density within the NUHM framework.


title:
A massive Feynman integral and some reduction relations for Appell
  functions

abstract:
  New explicit expressions are derived for the one-loop two-point Feynman
integral with arbitrary external momentum and masses $m_1^2$ and $m_2^2$ in D
dimensions. The results are given in terms of Appell functions, manifestly
symmetric with respect to the masses $m_i^2$. Equating our expressions with
previously known results in terms of Gauss hypergeometric functions yields
reduction relations for the involved Appell functions that are apparently new
mathematical results.


title:
Pion--deuteron scattering length in Chiral Perturbation Theory up to
  order \chi^{3/2}

abstract:
  A complete calculation of the corrections to pion-deuteron scattering length
up to order $\chi^{3/2}$ with $\chi=m_{\pi}/M_{N}$ is performed. The
calculation includes the dispersive contributions and corrections due to the
explicit treatment of the $\Delta$ resonance. s-wave pion-nucleon scattering
parameters are extracted from a combined analysis of modern experimental data.


title:
Unparticle physics and lepton flavor violating radion decays in the
  Randall-Sundrum scenario

abstract:
  We predict the branching ratios of the lepton flavor violating radion decays
r -> e^{\pm} \mu^{\pm}, r -> e^{\pm} \tau^{\pm} and r ->\mu^{\pm} \tau^{\pm} in
the framework of the Randall-Sundrum scenario that the lepton flavor violation
is carried by the scalar unparticle mediation. We observe that their BRs are
strongly sensitive to the unparticle scaling dimension and, for its small
values, the branching ratios can reach to the values of the order of 10^{-8},
for the heavy lepton flavor case.


title: On Capacity Scaling in Arbitrary Wireless Networks

abstract:
  In recent work, Ozgur, Leveque, and Tse (2007) obtained a complete scaling
characterization of throughput scaling for random extended wireless networks
(i.e., $n$ nodes are placed uniformly at random in a square region of area
$n$). They showed that for small path-loss exponents $\alpha\in(2,3]$
cooperative communication is order optimal, and for large path-loss exponents
$\alpha > 3$ multi-hop communication is order optimal. However, their results
(both the communication scheme and the proof technique) are strongly dependent
on the regularity induced with high probability by the random node placement.
  In this paper, we consider the problem of characterizing the throughput
scaling in extended wireless networks with arbitrary node placement. As a main
result, we propose a more general novel cooperative communication scheme that
works for arbitrarily placed nodes. For small path-loss exponents $\alpha \in
(2,3]$, we show that our scheme is order optimal for all node placements, and
achieves exactly the same throughput scaling as in Ozgur et al. This shows that
the regularity of the node placement does not affect the scaling of the
achievable rates for $\alpha\in (2,3]$. The situation is, however, markedly
different for large path-loss exponents $\alpha >3$. We show that in this
regime the scaling of the achievable per-node rates depends crucially on the
regularity of the node placement. We then present a family of schemes that
smoothly "interpolate" between multi-hop and cooperative communication,
depending upon the level of regularity in the node placement. We establish
order optimality of these schemes under adversarial node placement for $\alpha
> 3$.


title:
Actions of semisimple Lie groups preserving a degenerate Riemannian
  metric

abstract:
  We prove a rigidity of the lightcone in Minkowski space. It is essentially
the unique space endowed with a degenerate Riemannian metric, of lightlike
type, and supporting an isometric non-proper action of a semi-simple group.


title:
Development of New Hole-Type Avalanche Detectors and the First Results
  of their Applications

abstract:
  We have developed a new detector of photons and charged particles- a
hole-type structure with electrodes made of a double layered resistive
material: a thin low resistive layer coated with a layer having a much higher
resistivity. One of the unique features of this detector is its capability to
operate at high gas gains (up to 10E4) in air or in gas mixtures with air. They
can also operate in a cascaded mode or be combined with other detectors, for
example with GEM. This opens new avenues in their applications. Several
prototypes of these devices based on new detectors and oriented on practical
applications were developed and successfully tested: a detector of soft X-rays
and alpha particles, a flame sensor, a detector of dangerous gases. All of
these detectors could operate stably even in humid air and/or in dusty
conditions. The main advantages of these detectors are their simplicity, low
cost and high sensitivity. For example, due to the avalanche multiplication,
the detectors of flames and dangerous gases have a sensitivity of 10-100 times
higher than commercial devices. We therefore believe that new detectors will
have a great future.


title: Progress in NN --> NNpi

abstract:
  We survey the recent developments in the reaction $NN \to NN\pi$ in effective
field theory. We show that the proper construction of the production operator
needs a careful separation of irreducible pieces from reducible ones. The
result of this consideration is a complete cancellation of all loops in the
production operator at NLO. Moreover, we show that this procedure brings the
leading Weinberg-Tomozawa vertex on-shell, thus enhancing the corresponding
contribution to the transition amplitude by a factor of 4/3 as compared to the
commonly used value. We also discuss the role of the $\Delta(1232)$ for the
s-wave pion production. Being relatively sizable individually the direct and
rescattering mechanisms of the $\Delta$ excitation at NLO cancel each other to
a large extent. Thus, we conclude that the net effect of the $\Delta$ at NLO is
very small.


title: Diamond Solitaire

abstract:
  We investigate the game of peg solitaire on different board shapes, and find
those of diamond or rhombus shape have interesting properties. When one peg
captures many pegs consecutively, this is called a sweep. Rhombus boards of
side 6 have the property that no matter which peg is missing at the start, the
game can be solved to one peg using a maximal sweep of length 16. We show how
to construct a solution on a rhombus board of side 6i, where the final move is
a maximal sweep of length r, where r=(9i-1)(3i-1) is a "rhombic matchstick
number".


title:
Double Electromagnetically Induced Transparency in a Tripod-type Atom
  System

abstract:
  The electromagnetically induced transparency (EIT) phenomenon in a four level
atomic system with tripod configuration is studied. The results show that this
configuration is equivalent to the combination of two single three-level
$\Lambda$ configurations, which, under certain conditions, results in the
so-called double-EIT (DEIT) phenomenon. The properties of the double
transparency windows for DEIT are discussed in detail and the possible
experimental scheme is proposed.


title:
Estimation of the Repeatedly-Projected Reduced Density Matrix under
  Decoherence

abstract:
  Decoherence is believed to deteriorate the ability of a purification scheme
that is based on the idea of driving a system to a pure state by repeatedly
measuring another system in interaction with the former and hinder for a pure
state to be extracted asymptotically. Nevertheless, we find a way out of this
difficulty by deriving an analytic expression of the reduced density matrix for
a two-qubit system immersed in a bath. It is shown that we can still extract a
pure state if the environment brings about only dephasing effects. In addition,
for a dissipative environment, there is a possibility of obtaining a dominant
pure state when we perform a finite number of measurements.


title: Pulse phase resolved analysis of the HMXB Cen X-3 over two binary orbits

abstract:
  We present a detailed analysis of observations of the high mass X-ray binary
Cen X-3 spanning two consecutive binary orbits performed with the RXTE
satellite in early March 1997. The PCA and HEXTE light curves both show a clear
reduction in count rate after mid-orbit for both binary revolutions. We
therefore analyze two broad band spectra for each orbit, before and after
mid-orbit. Consistent with earlier observations these four joint PCA and HEXTE
spectra can be well described using a phenomenological pulsar continuum model,
including an iron emission line and a cyclotron resonance scattering feature.
While no strong spectral variations were detected, the second half of orbit 2
shows a tendency toward being softer and more strongly absorbed. In order to
follow the orbital phase-dependent evolution of the spectrum in greater detail,
we model spectra for shorter exposures, confirming that most spectral
parameters show either a gradual or sudden change for the second half of the
second orbit. A comparison with a simple wind model indicates the existence of
an accretion wake in this system. We also present and discuss high resolution
pulse profiles for several different energy bands, as well as their hardness
ratios. PCA and HEXTE spectra were created for 24 phase bins and fitted using
the same model as in the phase averaged case. Systematic pulse phase-dependent
variations of several continuum and cyclotron line parameters were detected,
most notably a significant increase of the cyclotron line energy during the
early rise of the main peak, followed by a gradual decrease. We show that
applying a simple dipole model for the magnetic field is not sufficient to
describe our data.


title:
Constraints on the TeV source population and its contribution to the
  galactic diffuse TeV emission

abstract:
  The detection by the HESS atmospheric Cerenkov telescope of fourteen new
sources from the Galactic plane makes it possible to estimate the contribution
of unresolved sources like those detected by HESS to the diffuse Galactic
emission measured by the Milagro Collaboration. The number-intensity relation
and the luminosity function for the HESS source population are investigated. By
evaluating the contribution of such a source population to the diffuse emission
we conclude that a significant fraction of the TeV energy emission measured by
the Milagro experiment could be due to unresolved sources like HESS sources.
Predictions concerning the number of sources which Veritas, Milagro, and HAWC
should detect are also given.


title: On the embedding of spacetime in five-dimensional Weyl spaces

abstract:
  We revisit Weyl geometry in the context of recent higher-dimensional theories
of spacetime. After introducing the Weyl theory in a modern geometrical
language we present some results that represent extensions of Riemannian
theorems. We consider the theory of local embeddings and submanifolds in the
context of Weyl geometries and show how a Riemannian spacetime may be locally
and isometrically embedded in a Weyl bulk. We discuss the problem of classical
confinement and the stability of motion of particles and photons in the
neighbourhood of branes for the case when the Weyl bulk has the geometry of a
warped product space. We show how the confinement and stability properties of
geodesics near the brane may be affected by the Weyl field. We construct a
classical analogue of quantum confinement inspired in theoretical-field models
by considering a Weyl scalar field which depends only on the extra coordinate.


title: Heat and Fluctuations from Order to Chaos

abstract:
  The Heat theorem reveals the second law of equilibrium Thermodynamics
(i.e.existence of Entropy) as a manifestation of a general property of
Hamiltonian Mechanics and of the Ergodic Hypothesis, valid for 1 as well as
$10^{23}$ degrees of freedom systems, {\it i.e.} for simple as well as very
complex systems, and reflecting the Hamiltonian nature of the microscopic
motion. In Nonequilibrium Thermodynamics theorems of comparable generality do
not seem to be available. Yet it is possible to find general, model
independent, properties valid even for simple chaotic systems ({\it i.e.} the
hyperbolic ones), which acquire special interest for large systems: the Chaotic
Hypothesis leads to the Fluctuation Theorem which provides general properties
of certain very large fluctuations and reflects the time-reversal symmetry.
Implications on Fluids and Quantum systems are briefly hinted. The physical
meaning of the Chaotic Hypothesis, of SRB distributions and of the Fluctuation
Theorem is discussed in the context of their interpretation and relevance in
terms of Coarse Grained Partitions of phase space. This review is written
taking some care that each section and appendix is readable either
independently of the rest or with only few cross references.


title: Multi-mass schemes for collisionless N-body simulations

abstract:
  We present a general scheme for constructing Monte Carlo realizations of
equilibrium, collisionless galaxy models with known distribution function (DF)
f_0. Our method uses importance sampling to find the sampling DF f_s that
minimizes the mean-square formal errors in a given set of projections of the DF
f_0. The result is a multi-mass N-body realization of the galaxy model in which
``interesting'' regions of phase-space are densely populated by lots of
low-mass particles, increasing the effective N there, and less interesting
regions by fewer, higher-mass particles.
  As a simple application, we consider the case of minimizing the shot noise in
estimates of the acceleration field for an N-body model of a spherical
Hernquist model. Models constructed using our scheme easily yield a factor ~100
reduction in the variance in the central acceleration field when compared to a
traditional equal-mass model with the same number of particles. When evolving
both models with a real N-body code, the diffusion coefficients in our model
are reduced by a similar factor. Therefore, for certain types of problems, our
scheme is a practical method for reducing the two-body relaxation effects,
thereby bringing the N-body simulations closer to the collisionless ideal.


title: Boundary effects in a three-state modified voter model for languages

abstract:
  The standard three-state voter model is enlarged by including the outside
pressure favouring one of the three choices and by adding some biased internal
random noise. The Monte Carlo simulations are motivated by states with the
population divided into three groups of various affinities to each other. We
show the crucial influence of the boundaries for moderate lattice sizes like
500 x 500. By removing the fixed boundary at one side, we demonstrate that this
can lead to the victory of one single choice. Noise in contrast stabilizes the
choices of all three populations. In addition, we compute the persistence
probability, i.e., the number of sites who have never changed their opinion
during the simulation, and we consider the case of "rigid-minded" decision
makers.


title: Rational curves of degree 11 on a general quintic threefold

abstract:
  We prove that the incidence scheme of rational curves of degree 11 on quintic
threefolds is irreducible. This implies a strong form of the Clemens conjecture
in degree 11. Namely, on a general quintic threefold $F$ in $\mathbb{P}^4$,
there are only finitely many smooth rational curves of degree 11, and each
curve $C$ is embedded in $F$ with normal bundle $\mathcal{O}(-1) \oplus
\mathcal{O}(-1)$. Moreover, in degree 11, there are no singular, reduced, and
irreducible rational curves, nor any reduced, reducible, and connected curves
with rational components on $F$.


title: Gauge-Invariant Quantities Characterizing Gauge Fields in Chromodynamics

abstract:
  We calculate Lorentz-invariant and gauge-invariant quantities characterizing
the product $\sum_a D_R(T^a) F^a_{\mu\nu}$, where $D_R(T^a)$ denotes the matrix
for the generator $T^a$ in the representation $R=$ fundamental and adjoint, for
color SU(3). We also present analogous results for an SU(2) gauge theory.


abstract:
  It is suggested that a new area of CSCR (Computer Supported Collaborative
Research) is distinguished from CSCW (Computer Supported Collaborative Work)
and CSCL (Computer Supported Collaborative Learning) and that the demarcation
between the three areas could do with greater clarification and prescription.
  Although the areas of Human Computer Interaction (HCI), CSCW, and CSCL are
now relatively well established, the related field of Computer Supported
Collaborative Research (CSCR) is new and little understood. An analysis of the
principles and issues behind CSCR is undertaken with a view to determining
precisely its nature and scope and to delineate it clearly from CSCW and CSCL.
This determination is such that it is generally applicable to the building,
design and evaluation of collaborative research environments.
  A particular instance of the CSCR domain is then examined in order to
determine the requirements of a collaborative research environment for students
and supervisors (CRESS).


title:
Multimodal Horizontal Branches: Empirical Evidence and Possible
  Evolutionary Scenarios

abstract:
  We review the available empirical evidence for the presence of "gaps" and
multimodal distributions among horizontal branch (HB) stars, along with some of
the theoretical scenarios that have been proposed to explain these features.
While gaps along the HB have become increasingly less prominent and frequent as
more and better color-magnitude diagram data have been obtained for Galactic
globular clusters, the evidence for multimodal HBs has instead become stronger.
In addition, different HB modes have recently started to be traced down to
multiple components that have been detected among subgiant branch and main
sequence stars, thus suggesting that their origin lies in the complex physical
processes that took place at the earliest stages in the history of massive
stellar clusters.


title:
Variations on Information Embedding in Multiple Access and Broadcast
  Channels

abstract:
  Information embedding (IE) is the transmission of information within a host
signal subject to a distortion constraint. There are two types of embedding
methods, namely irreversible IE and reversible IE, depending upon whether or
not the host, as well as the message, is recovered at the decoder. In
irreversible IE, only the embedded message is recovered at the decoder, and in
reversible IE, both the message and the host are recovered at the decoder. This
paper considers combinations of irreversible and reversible IE in multiple
access channels (MAC) and physically degraded broadcast channels (BC).


title:
High resolution x-ray study of nematic-smectic-A and Smectic-A-reentrant
  nematic transitions in liquid crystal+aerosil gels

abstract:
  We have studied the effects of quenched random disorder created by dispersed
aerosil nanoparticle gels on the nematic to smectic-A (N-SmA) and smectic-A to
reentrant nematic (SmA- RN) phase transitions of thermotropic liquid crystal
mixtures of 6OCB (hexyloxycyanobiphenyl) and 8OCB (octyloxycyanobiphenyl).
These effects are probed using high-resolution synchrotron x-ray diffraction
techniques. We find that the reentrant characteristics of the system are
largely unchanged by the presence of the aerosil gel network. By comparing
measurements of the smectic static structure amplitude for this
8OCB-6OCB+aerosil system with those for butyloxybenzilidene-octylaniline
(4O.8)+aerosil gels, we find that the short-range smectic order in the
smectic-A phase is significantly weaker in the reentrant system. This result is
consistent with the behavior seen in pure 8OCB-6OCB mixtures. The strength of
the smectic ordering decreases progressively as the 6OCB concentration is
increased. Detailed line shape analysis shows that the high- and
low-temperature nematic phases (N and RN) are similar to each other.


title:
Constructing quantized enveloping algebras via inverse limits of finite
  dimensional algebras

abstract:
  It is known that a generalized $q$-Schur algebra may be constructed as a
quotient of a quantized enveloping algebra $\UU$ or its modified form
$\dot{\UU}$. On the other hand, we show here that both $\UU$ and $\dot{\UU}$
may be constructed within an inverse limit of a certain inverse system of
generalized $q$-Schur algebras. Working within the inverse limit $\hat{\UU}$
clarifies the relation between $\dot{\UU}$ and $\UU$. This inverse limit is a
$q$-analogue of the linear dual $R[G]^*$ of the coordinate algebra of a
corresponding linear algebraic group $G$.


title: Quantum Tomography of a system of three-level atoms

abstract:
  We analyze the possibility of tomographic reconstruction of a system of
three-level atoms in both non-degenerate and degenerate cases. In the
non-degenerate case (when both transitions can be accessed independently) a
complete reconstruction is possible. In the degenerate case (when both
transitions are excited simultaneously) the complete reconstruction is
achievable only for a single atom in the Sigma configuration. For multiple
Sigma atoms, or even a single atom in the Lambda configuration, only partial
reconstruction is possible. Examples of one and two-atom cases are explicitly
considered.


title: Superconnections and Parallel Transport

abstract:
  This note addresses the construction of a notion of parallel transport along
superpaths arising from the concept of a superconnection on a vector bundle
over a manifold $M$. A superpath in $M$ is, loosely speaking, a path in $M$
together with an odd vector field in $M$ along the path. We also develop a
notion of parallel transport associated with a connection (a.k.a. covariant
derivative) on a vector bundle over a \emph{supermanifold} which is a direct
generalization of the classical notion of parallel transport for connections
over manifolds.


title: Geometric Structure of Two Self-dual Fields with Constraints

abstract:
  A two dimensional Poincar$\acute{e}$-invariant self-dual field with
constraints is studied in geometric way. We obtained its symplectic structure
and conservative currents on space of solutions, which are also invariant under
transformations of Poincar$\acute{e}$ group.


title: Reply To "Comment on 'Quantum String Seal Is Insecure' "

abstract:
  In Phys. Rev. A. 76, 056301 (2007), He claimed that the proof in my earlier
paper [Phys. Rev. A 75, 012327 (2007)] is insufficient to conclude the
insecurity of all quantum string seals because my measurement strategy cannot
obtain non-trivial information on the sealed string and escape detection at the
same time. Here, I clarify that our disagreement comes from our adoption of two
different criteria on the minimum amount of information a quantum string seal
can reveal to members of the public. I also point out that He did not follow my
measurement strategy correctly.


title: A new proof of a theorem of Mansour and Sun

abstract:
  We give a new proof of a theorem of Mansour and Sun by using number theory
and Rothe's identity.


title: Dynamical compactifications of C^2

abstract:
  We find good dynamical compactifications for arbitrary polynomial mappings of
C^2 and use them to show that the degree growth sequence satisfies a linear
integral recursion formula. For maps of low topological degree we prove that
the Green function is well behaved. For maps of maximum topological degree, we
give normal forms.


title: Analytic approximation of matrix functions and dual extremal functions

abstract:
  We study the question of the existence of a dual extremal function for a
bounded matrix function on the unit circle in connection with the problem of
approximation by analytic matrix functions. We characterize the class of matrix
functions, for which a dual extremal function exists in terms of the existence
of a maximizing vector of the corresponding Hankel operator and in terms of
certain special factorizations that involve thematic matrix functions.


title: The effect of energy amplification variance on the shock-acceleration

abstract:
  The shock-acceleration theory predicts a power-law energy spectrum in the
test particle approximation, and there are two ways to calculate a power-law
index, Peacock's approximation and Vietri's formulation. In Peacock's
approximation, it is assumed that particles cross a shock front many times and
energy-gains for each step are fully uncorrelated. On the other hand,
correlation of the distribution of an energy-gain factor for a particle is
considered in Vietri's formulation. We examine how Peacock's approximation
differs from Vietri's formulation. It is useful to know when we can use
Peacock's approximation because Peacock's approximation is simple to derive the
power-law index. In addition, we focus on how the variance of the energy-gain
factor has an influence on the difference between Vietri's formulation and
Peacock's approximation. The effect of the variance has not been examined well
until now. For demonstration, we consider two cases for the scattering in the
upstream: the large-angle scattering (model A) and the regular deflection by
large-scale magnetic fields (model B). Especially there is no correlation among
the distribution of an energy-gain factor for every step in model A. In this
model, we see the power-law index derived from Peacock's approximation differs
from the one derived from Vietri's formulation when we consider the
mildly-relativistic shock, and the variance of the energy-gain factor affects
this difference. We can use Peacock's approximation for a non-relativistic
shock and a highly-relativistic shock because the effect of the variance is
hidden. In model B, we see the difference of the power-law converging along the
shock velocity.


title:
Geometric vs. Dynamical Gates in Quantum Computing Implementations Using
  Zeeman and Heisenberg Hamiltonians

abstract:
  Quantum computing in terms of geometric phases, i.e. Berry or
Aharonov-Anandan phases, is fault-tolerant to a certain degree. We examine its
implementation based on Zeeman coupling with a rotating field and isotropic
Heisenberg interaction, which describe NMR and can also be realized in quantum
dots and cold atoms. Using a novel physical representation of the qubit basis
states, we construct $\pi/8$ and Hadamard gates based on Berry and
Aharonov-Anandan phases. For two interacting qubits in a rotating field, we
find that it is always impossible to construct a two-qubit gate based on Berry
phases, or based on Aharonov-Anandan phases when the gyromagnetic ratios of the
two qubits are equal. In implementing a universal set of quantum gates, one may
combine geometric $\pi/8$ and Hadamard gates and dynamical $\sqrt{\rm SWAP}$
gate.


title: Mathematical Constraints on Gauge in Maxwellian Electrodynamics

abstract:
  The structure of classical electrodynamics based on the variational principle
together with causality and space-time homogeneity is analyzed. It is proved
that in this case the 4-potentials are defined uniquely. On the other hand, the
approach where Maxwell equations and the Lorentz law of force are regarded as
cornerstones of the theory allows gauge transformations. For this reason, the
two theories are not equivalent. A simple example substantiates this
conclusion. Quantum physics is linked to the variational principle and it is
proved that the same result holds for it. The compatibility of this conclusion
with gauge invariance of the Lagrangian density is explained. Several
alternative possibilities that may follow this work are pointed out.


title: The special linear representations of compact Lie groups

abstract:
  The special linear representation of a compact Lie group G is a kind of
linear representation of compact Lie group G with special properties. It is
possible to define the integral of linear representation and extend this
concept to special linear representation for next using.


title: Gamma Standing Wave in the Photonic Crystal of Resonant Rh Nuclei

abstract:
  In a previous report, we have shown that the rhodium lattice consisting of
resonant nuclei is an ideal photonic crystal in nature. Plenty of extraordinary
observations are attributed to the collective down conversion of the multipolar
nuclear transition; in particular the spontaneous open up of photonic band gap.
Emissions of directionality depending on the macroscopic geometry manifest that
the standing wave is global in the polycrystalline sample. In this work,
further observations of the directional emissions are summarized. By applying
an external magnetic field at room temperature, not only the predicted
macroscopic nuclear polarization but also its strong directionality are
demonstrated. The standing wave lasts for more than hundred hours at room
temperature in the single crystal despite its natural half-life of one hour.
The so-called nuclear Raman Effect between two M4 transitions of 193mIr and
195mPt and the E3 transition of 103mRh is discovered, which gives the brand new
aspects to detect gravitational waves.


title: The Schroedinger operator as a generalized Laplacian

abstract:
  The Schroedinger operators on the Newtonian space-time are defined in a way
which make them independent on the class of inertial observers. In this picture
the Schroedinger operators act not on functions on the space-time but on
sections of certain one-dimensional complex vector bundle -- the Schroedinger
line bundle. This line bundle has trivializations indexed by inertial observers
and is associated with an U(1)-principal bundle with an analogous list of
trivializations -- the Schroedinger principal bundle. For the Schroedinger
principal bundle a natural differential calculus for `wave forms' is developed
that leads to a natural generalization of the concept of Laplace-Beltrami
operator associated with a pseudo-Riemannian metric. The free Schroedinger
operator turns out to be the Laplace-Beltrami operator associated with a
naturally distinguished invariant pseudo-Riemannian metric on the Schroedinger
principal bundle. The presented framework is proven to be strictly related to
the frame-independent formulation of analytical Newtonian mechanics and
Hamilton-Jacobi equations, that makes a bridge between the classical and
quantum theory.


title:
Formation and dynamics of many-boson fragmented states in attractive
  one-dimensional ultra-cold gases

abstract:
  Dynamics of attractive ultra-cold bosonic clouds in one dimension are studied
by solving the many-particle time-dependent Schr\"odinger equation. The
initially coherent wave-packet can dynamically dissociate into two parts when
its energy exceeds a threshold value. Noticeably, the time-dependent
Gross-Pitaevskii theory applied to the same initial state does not show up the
splitting. We call the split object {\it fragmenton}. It possesses remarkable
properties: (1) it is two-fold fragmented, i.e., not coherent; (2) it is
dynamically stable, i.e., it propagates almost without dispersion; (3) it is
delocalized, i.e., the two dissociated parts still communicate with one
another. A simple static model predicts the existence of fragmented states
which are responsible for formation and dynamics of fragmentons.


title: The Generalized Classical Time-Space

abstract:
  The newest model for space-time is based on sub-Riemannian geometry. In this
paper, we use a combination of Lorentzian and sub-Riemannian geometry, the
suggest a new model which likes to its ancestors, but with the most efficient
in application. In continuation, we try to show a new connection which calls
generalized connection, and prove some its properties.


title:
Epcast: Controlled Dissemination in Human-based Wireless Networks by
  means of Epidemic Spreading Models

abstract:
  Epidemics-inspired techniques have received huge attention in recent years
from the distributed systems and networking communities. These algorithms and
protocols rely on probabilistic message replication and redundancy to ensure
reliable communication. Moreover, they have been successfully exploited to
support group communication in distributed systems, broadcasting, multicasting
and information dissemination in fixed and mobile networks. However, in most of
the existing work, the probability of infection is determined heuristically,
without relying on any analytical model. This often leads to unnecessarily high
transmission overheads.
  In this paper we show that models of epidemic spreading in complex networks
can be applied to the problem of tuning and controlling the dissemination of
information in wireless ad hoc networks composed of devices carried by
individuals, i.e., human-based networks. The novelty of our idea resides in the
evaluation and exploitation of the structure of the underlying human network
for the automatic tuning of the dissemination process in order to improve the
protocol performance. We evaluate the results using synthetic mobility models
and real human contacts traces.


title:
Simulation of the flyby anomaly by means of an empirical asymmetric
  gravitational field with definite spatial orientation

abstract:
  All anomalous velocity increases until now observed during the Earth flybys
of the spacecrafts Galileo, NEAR, Rosetta, Cassini and Messenger have been
correctly calculated by computer simulation using an asymmetric field term in
addition to the Newtonian gravitational field. The specific characteristic of
this term is the lack of coupling to the rotation of the Earth or to the
direction of other gravitational sources such as the Sun or Moon. Instead, the
asymmetry is oriented in the direction of the Earth's motion within an assumed
unique reference frame. With this assumption, the simulation results of the
Earth flybys Galileo1, NEAR, Rosetta1 and Cassini hit the observed nominal
values, while for the flybys Galileo2 and Messenger, which for different
reasons are measured with uncertain anomaly values, the simulated anomalies are
within plausible ranges. Furthermore, the shape of the simulated anomaly curve
is in qualitative agreement with the measured Doppler residuals immediately
following the perigee of the first Earth flyby of Galileo. Based on the
simulation, an estimation is made for possible anomalies of the recently
carried out flybys of Rosetta at Mars on 25.02.07 and at the Earth on 13.11.07,
and for the forthcoming Earth flyby on 13.11.09. It is discussed, why a so
modelled gravitational field has not been discovered until now by analysis of
the orbits of Earth satellites, and what consequences are to be considered with
respect to General Relativity.


title:
Interrelation of fast and slow electron waves at propagation of
  electromagnetic waves in Maxwellian collisionless plasma

abstract:
  It is shown in linear approximation that in the case of one-dimensional
problem of transverse electron waves in a half-infinite slab of homogeneous
Maxwellian collisionless plasma with the given boundary field frequency two
wave branches of solution of the dispersion equation are simultaneously
realizing. These are the branch of fast forward waves determined mainly by
Maxwell equations of electromagnetic field, as well as the branch of forward
and backward slow waves determined in the whole by kinetic properties of
electrons in the collective electrical field. The physical nature of wave
movements is revealed. A relation is found between electric field amplitudes of
fast and slow waves. Multiform dividing the coupled slow waves into standing
and traveling parts leads to a necessity of additional requirements to a
selection of the type of a device analyzing these waves and its response
interpretation.


title: First images of 6.7-GHz methanol masers in DR21(OH) and DR21(OH)N

abstract:
  The first images of 6.7-GHz methanol masers in the massive star-forming
regions DR21(OH) and DR21(OH)N are presented. By measuring the shapes, radial
velocities and polarization properties of these masers it is possible to map
out the structure, kinematics and magnetic fields in the molecular gas that
surrounds newly-formed massive stars. The intrinsic angular resolution of the
observations was 43 mas (~100 AU at the distance of DR21), but structures far
smaller than this were revealed by employing a non-standard mapping technique.
This technique was used in an attempt to identify the physical structure (e.g.
disc, outflow, shock) associated with the methanol masers. Two distinct
star-forming centres were identified. In DR21(OH) the masers had a linear
morphology, and the individual maser spots each displayed an internal velocity
gradient in the same direction as the large-scale structure. They were detected
at the same position as the OH 1.7-GHz ground-state masers, close to the centre
of an outflow traced by CO and class I methanol masers. The shape and velocity
gradients of the masers suggests that they probably delineate a shock. In
DR21(OH)N the methanol masers trace an arc with a double-peaked profile and a
complex velocity gradient. This velocity gradient closely resembles that of a
Keplerian disc. The masers in the arc are 4.5% linearly polarized, with a
polarization angle that indicates that the magnetic field direction is roughly
perpendicular to the large-scale magnetic field in the region (indicated by
lower angular resolution measurements of the CO and dust polarization). The
suitability of channel-by-channel centroid mapping is discussed as an improved
and viable means to maximise the information gained from the data.


title:
A cluster density matrix for the effective field theory with
  correlations

abstract:
  A cluster density matrix is introduced in the form suitable for the
self-consistent calculation of relevant thermodynamic averages for the Ising
model with spin S=1/2. On this basis, derivation of the Gibbs free-energy for
the effective field theory of Honmura and Kaneyoshi is presented.


title: Binary nonlinearization of the super AKNS system

abstract:
  We establish the binary nonlinearization approach of the spectral problem of
the super AKNS system, and then use it to obtain the super finite-dimensional
integrable Hamiltonian system in supersymmetry manifold $\mathbb{R}^{4N|2N}$.
The super Hamiltonian forms and integrals of motion are given explicitly.


title: Infra-Red Surface-Plasmon-Resonance technique for biological studies

abstract:
  We report on a Surface-Plasmon-Resonance (SPR) technique based on Fourier
-Transform - Infra - Red (FTIR) spectrometer. In contrast to the conventional
surface plasmon technique, operating at a fixed wavelength and a variable angle
of incidence, our setup allows the wavelength and the angle of incidence to be
varied simultaneously. We explored the potential of the SPR technique in the
infrared for biological studies involving aqueous solutions. Using computer
simulations, we found the optimal combination of parameters (incident angle,
wavelength) for performing this task. Our experiments with physiologically
important glucose concentrations in water and in human plasma verified our
computer simulations. Importantly, we demonstrated that the sensitivity of the
SPR technique in the infrared range is not lower and in fact is even higher
than that for visible light. We emphasize the advantages of infra red SPR for
studying glucose and other biological molecules in living cells.


title: Locally accessible information from multipartite ensembles

abstract:
  We present a universal Holevo-like upper bound on the locally accessible
information for arbitrary multipartite ensembles. This bound allows us to
analyze the indistinguishability of a set of orthogonal states under LOCC. We
also derive the upper bound for the capacity of distributed dense coding with
multipartite senders and multipartite receivers.


title:
The one-loop renormalization of the gauge sector in the \theta-expanded
  noncommutative standard model

abstract:
  In this paper we construct a version of the standard model gauge sector on
noncommutative space-time which is one-loop renormalizable to first order in
the expansion in the noncommutativity parameter $\theta$.


title: Is the chiral phase transition induced by a metal-insulator transition?

abstract:
  We investigate the QCD Dirac operator with gauge configurations given by a
liquid of instantons in the region of temperatures about the chiral phase
transition. Both the quenched and unquenched cases are examined in detail. We
present evidence of a localization transition in the low lying modes of the
  Dirac operator around the same temperature as the chiral phase transition.
Thus both level statistics and eigenvectors of the QCD Dirac operator at the
chiral phase transition have similar properties than those of a disordered
conductor at the metal-insulator transition. This strongly suggests the
phenomenon of Anderson localization (localization by destructive quantum
interference) is the leading physical mechanism in the restoration of the
chiral symmetry. Finally we argue that our findings are not in principle
restricted to the ILM approximation and may also be found in lattice
simulations.


title:
Problem with the Derivation of the Navier-Stokes Equation by Means of
  Zwanzig-Mori Projection Technique of Statistical Mechanics

abstract:
  The derivation of the Navier-Stokes equation starting from the Liouville
equation using projection techniques yields a friction term which is nonlinear
in the velocity. Using the results of multilinear mode-coupling technique for
calculating equlibrium correlation functions, it is shown that the second-order
part of the term is non-zero, thus leading to an incorrect formula for the
equation.


title: Constraining MOND with Solar System dynamics

abstract:
  In this letter we investigate the deep Newtonian regime of the MOND paradigm
from a purely phenomenological point of view by exploiting the least-square
estimated corrections to the secular rates of the perihelia of the inner and of
some of the outer planets of the Solar System by E.V. Pitjeva with the EPM2004
ephemerides. By using $\mu(x)\approx 1-k_0(1/x)^n$ for the interpolating
MONDian function, and by assuming that $k_0$, considered body-independent so to
avoid violations of the equivalence principle, experiences no spatial
variations throughout the Solar System we tightly constrain $n$ with the ratios
of the perihelion precessions for different pairs of planets. We find that the
range $1\leq n\leq 2$ is neatly excluded at much more than $3-\sigma$ level.
Such a test would greatly benefit from the use of extra-precessions of
perihelia independently estimated by other groups as well.


title: Discrete States in Light-Like Linear Dilaton Background

abstract:
  We study the spectrum of bosonic strings in the light-like linear dilaton
background and find discrete states. These are physical states which exist only
at specific values of momentum. All except one discrete states generate
spacetime symmetries. The exceptional discrete state corresponds to constraints
which are deformations of conservation laws. The constraints resemble those
arising from symmetries, and are equally powerful, suggesting that our notion
of symmetry should be generalized.


title: Long-Time Asymptotics for the Toda Lattice in the Soliton Region

abstract:
  We apply the method of nonlinear steepest descent to compute the long-time
asymptotics of the Toda lattice for decaying initial data in the soliton
region. In addition, we point out how to reduce the problem in the remaining
region to the known case without solitons.


title: Representation dimension and finitely generated cohomology

abstract:
  We consider selfinjective Artin algebras whose cohomology groups are finitely
generated over a central ring of cohomology operators. For such an algebra, we
show that the representation dimension is strictly greater than the maximal
complexity occurring among its modules. This provides a unified approach to
computing lower bounds for the representation dimension of group algebras,
exterior algebras and Artin complete intersections. We also obtain new examples
of classes of algebras with arbitrarily large representation dimension.


title: The ideas behind the Self Consistent Expansion

abstract:
  In recent years we have witnessed a growing interest in various
non-equilibrium systems described in terms of stochastic non-linear field
theories. In some of those systems like the KPZ and related models, the
interesting behavior is in the strong coupling regime, which is inaccessible by
traditional perturbative treatments such as dynamical renormalization group
(DRG). A useful tool in the study of such system is the Self Consistent
Expansion (SCE), which might be said to generate its own "small parameter" .The
self consistent expansion (SCE) has the advantage that its structure is just
that of a regular expansion, the only difference is that the simple system
around which the expansion is performed is adjustable. The purpose of the this
article is to present the method in a simple and understandable way, that
hopefully will make it accessible to a wider public working on non-equilibrium
statistical physics.


title: On Lie groups as quasi-K\"ahler manifolds with Killing Norden metric

abstract:
  A 6-parametric family of 6--dimensional quasi-K\"ahler manifolds with Norden
metric is constructed on a Lie group. This family is characterized
geometrically.


title: Emergent Gravity And The Cosmological Constant Problem

abstract:
  We address issues on the origin of gravity and the cosmological constant
problem based on a recent understanding about the correspondence between
noncommutative field theory and gravity. We suggest that the cosmological
constant problem can be resolved in a natural way if gravity emerges from a
gauge theory in noncommutative spacetime. Especially, we elucidate why the
emergent gravity implies that vacuum energy does not gravitate but only
fluctuations around the vacuum generate gravity. That is, a flat spacetime
emerges from uniform condensation of energy, previously identified with the
cosmological constant.


title:
Almost hypercomplex pseudo-Hermitian manifolds and a 4-dimensional Lie
  group with such structure

abstract:
  Almost hypercomplex pseudo-Hermitian manifolds are considered. Isotropic
hyper-K\"ahler manifolds are introduced. A 4-parametric family of 4-dimensional
manifolds of this type is constructed on a Lie group. This family is
characterized geometrically. The condition a 4-manifold to be isotropic
hyper-K\"ahler is given.


title: Large attractors in cooperative bi-quadratic Boolean networks. Part I

abstract:
  Boolean networks have been the object of much attention, especially since S.
Kauffman proposed them in the 1960's as models for gene regulatory networks.
These systems are characterized by being defined on a Boolean state space and
by simultaneous updating at discrete time steps. Of particular importance for
biological applications are networks in which the indegree for each variable is
bounded by a fixed constant, as was stressed by Kauffman in his original
papers.
  An important question is which conditions on the network topology can rule
out exponentially long periodic orbits in the system. In this paper, we
consider systems with positive feedback interconnections among all variables
(known as cooperative systems), which in a continuous setting guarantees a very
stable dynamics. We show that for an arbitrary constant 0<c<2 and sufficiently
large n there exist n-dimensional cooperative Boolean networks in which both
the indegree and outdegree of each variable is bounded by two, and which
nevertheless contain periodic orbits of length at least c^n. In Part II of this
paper we will prove an inverse result showing that any system with such a
dynamic behavior must in a sense be similar to the example described.


title: Parameter testing with bounded degree graphs of subexponential growth

abstract:
  Parameter testing algorithms are using constant number of queries to estimate
the value of a certain parameter of a very large finite graph. It is well-known
that graph parameters such as the independence ratio or the edit-distance from
3-colorability are not testable in bounded degree graphs. We prove, however,
that these and several other interesting graph parameters are testable in
bounded degree graphs of subexponential growth.


title:
Inverse Sampling for Nonasymptotic Sequential Estimation of Bounded
  Variable Means

abstract:
  In this paper, we consider the nonasymptotic sequential estimation of means
of random variables bounded in between zero and one. We have rigorously
demonstrated that, in order to guarantee prescribed relative precision and
confidence level, it suffices to continue sampling until the sample sum is no
less than a certain bound and then take the average of samples as an estimate
for the mean of the bounded random variable. We have developed an explicit
formula and a bisection search method for the determination of such bound of
sample sum, without any knowledge of the bounded variable. Moreover, we have
derived bounds for the distribution of sample size. In the special case of
Bernoulli random variables, we have established analytical and numerical
methods to further reduce the bound of sample sum and thus improve the
efficiency of sampling. Furthermore, the fallacy of existing results are
detected and analyzed.


title: *-Doubles and embedding of associative algebras in B(H)

abstract:
  We study the *-double functor between the categories of associative and
involutive algebras. It is proved that an associative algebra is isomorphic to
a subalgebra of a $C\sp*$-algebra if and only if its *-double is *-isomorphic
to a *-subalgebra of a $C\sp*$-algebra. Some applications in the theory of
operator algebras are presented. In particular each operator algebra is shown
to be completely boundedly isomorphic to an operator algebra $B$ with the
greatest $C\sp*$-subalgebra consisting of the multiples of the unit and such
that each element in $B$ is determined by its module up to a scalar multiple.
We also study the maximal subalgebras of an operator algebra $A$ which are
mapped into $C\sp*$-algebras under completely bounded faithful representations
of $A$.


title: On Non-handlebody Instantons in 3D Gravity

abstract:
  In this note we describe the contribution from non-handlebody geometries to
the partition function of three-dimensional pure gravity with negative
cosmological constant on a Riemann surface of genus greater than one, extending
previous considerations for handlebodies.


title:
On Gamma Ray Burst and Blazar AGN Origins of the Ultra-High Energy
  Cosmic Rays in Light of First Results from Auger

abstract:
  The discoveries of the GZK cutoff with the HiRes and Auger Observatories and
the discovery by Auger of clustering of >~60 EeV ultra-high energy cosmic rays
(UHECRs) towards nearby <~75 Mpc) AGNs along the supergalactic plane
establishes the astrophysical origin of the UHECRs. The likely sources of the
UHECRs are gamma-ray bursts and radio-loud AGNs because: (1) they are
extragalactic; (2) they are sufficiently powerful; (3) acceleration to
ultra-high energies can be achieved in their relativistic ejecta; (4) anomalous
X-ray and gamma-ray features can be explained by nonthermal hadron acceleration
in relativistic blast waves; and (5) sources reside within the GZK radius. Two
arguments for acceleration to UHE are presented, and limits on UHECR ion
acceleration are set. UHECR ions are shown to be able to survive without
photodisintegrating while passing through the AGN scattered radiation field,
even if launched deep in the broad line region. UHECR injection throughout
cosmic time fits the measured energy spectrum of UHECRs, at least for protons.
Local UHECR proton and ion interaction and energy-loss mean free paths are
calculated using an empirical fit to the extragalactic background light (EBL)
at IR and optical energies. Minimum intergalactic magnetic (IGM) fields ~1e-11
G are derived from clustering assuming specific source origins, e.g., Cen A,
nearby AGNs, or GRBs for the super-GZK CRs seen with Auger. Besides distinct
cosmic-ray induced gamma-ray signatures that should be observed with the Gamma
ray Large Area Space Telescope (GLAST), source and GZK neutrino detections and
the arrival distribution of UHECR in direction and time can finally decide the
sources of cosmic rays at the highest energies.


title: Exit Doorway Model for Nuclear Breakup of Weakly Bound Projectiles

abstract:
  We derive closed expressions for the nuclear breakup cross sections in the
adiabatic limit using the Austern-Blair theory. These expressions are
appropriate for the breakup of weakly bound nuclei. The concept of an exit
doorway that mediates the coupling between the entrance channel and the breakup
continuum is used. We prove the validity of the scaling law that dictates that
the nuclear breakup cross section scales linearly with the radius of the
target. We also compare our results for the nuclear breakup cross section of
$^{11}$Be, $^8$B on several targets with recent CDCC calculation.


title: Perturbative Treatment of Symmetry Breaking Within Random Matrix Theory

abstract:
  We discuss the applicability, within the Random Matrix Theory, of
perturbative treatment of symmetry breaking to the experimental data on the
flip symmetry breaking in quartz crystal. We found that the values of the
parameter that measures this breaking are different for the spacing
distribution as compared to those for the spectral rigidity. We consider both
twofold and threefold symmetries. The latter was found to account better for
the spectral rigidity than the former. Both cases, however, underestimate the
experimental spectral rigidity at large L. This discrepancy can be resolved if
an appropriate number of eigenfrequecies is considered to be missing in the
sample. Our findings are relevant to isospin violation study in nuclei.


title:
Pricing Equity Default Swaps under an approximation to the CGMY L\'{e}%
  vy Model

abstract:
  The Wiener-Hopf factorization is obtained in closed form for a phase type
approximation to the CGMY L\'{e}vy process. This allows, for the approximation,
exact computation of first passage times to barrier levels via Laplace
transform inversion. Calibration of the CGMY model to market option prices
defines the risk neutral process for which we infer the first passage times of
stock prices to 30% of the price level at contract initiation. These
distributions are then used in pricing 50% recovery rate equity default swap
(EDS) contracts and the resulting prices are compared with the prices of credit
default swaps (CDS). An illustrative analysis is presented for these contracts
on Ford and GM.


title:
The growth at infinity of a sequence of entire functions of bounded
  orders

abstract:
  In this paper we shall consider the growth at infinity of a sequence $(P_n)$
of entire functions of bounded orders. Our results extend the results in
\cite{trong-tuyen2} for the growth of entire functions of genus zero. Given a
sequence of entire functions of bounded orders $P_n(z)$, we found a nearly
optimal condition, given in terms of zeros of $P_n$, for which $(k_n)$ that we
have \begin{eqnarray*} \limsup_{n\to\infty}|P_n(z)|^{1/k_n}\leq 1
\end{eqnarray*} for all $z\in \mathbb C$ (see Theorem \ref{theo5}). Exploring
the growth of a sequence of entire functions of bounded orders lead naturally
to an extremal function which is similar to the Siciak's extremal function (See
Section 6).


title: Root Systems for Levi Factors and Borel-de Siebenthal Theory

abstract:
  Let $\frak{m}$ be a Levi factor of a proper parabolic subalgebra $\frak{q}$
of a complex semisimple Lie algebra $\frak{g}$. Let $\frak{t} = cent \frak{m}$.
A nonzero element $\nu \in \frak{t}^*$ is called a $\frak {t}$-root if the
corresponding adjoint weight space $\frak{g}_{nu}$ is not zero. If $\nu$ is a
$\frak{t}$-root, some time ago we proved that $\frak{g}_{\nu}$ is $ad \frak{m}$
irreducible. Based on this result we develop in the present paper a theory of
$\frak{t}$-roots which replicates much of the structure of classical root
theory (case where $\frak{t}$ is a Cartan subalgebra). The results are applied
to obtain new reults about the structure of the nilradical $\frak{n}$ of
$\frak{q}$. Also applications in the case where $dim \frak{t}=1$ are used in
Borel-de Siebenthal theory to determine irreducibility theorems for certain
equal rank subalgebras of $\frak{g}$. In fact the irreducibility results
readily yield a proof of the main assertions of the Borel-de Siebenthal theory.


title:
The Lie module structure on the Hochschild cohomology groups of monomial
  algebras with radical square zero

abstract:
  We study the Lie module structure given by the Gerstenhaber bracket on the
Hochschild cohomology groups of a monomial algebra with radical square zero.
The description of such Lie module structure will be given in terms of the
combinatorics of the quiver. The Lie module structure will be related to the
classification of finite dimensional modules over simple Lie algebras when the
quiver is given by the two loops and the ground field is the complex numbers.


title:
Une approche par les mod\`eles pour le suivi de l'activit\'e de
  construction d'un b\^atiment. Bat'iViews : une interface multi-vues
  orient\'ee gestion de chantier

abstract:
  Cooperation between actors in design and construction activities in
architecture is an essential stake nowadays. In professional practices the
actors involved in construction projects use numerous tools. The project is
unique but the "views" that actors manipulate are various and sometimes
fundamentally different. Their common characteristic is that they partially
represent the cooperation context through a specific point of view.
"Bat'iViews" suggests to the actors a multi-view interface of the context and
enables to navigate through the different views. This proposition is based on a
model-driven approach. We distinguish between "context modelling" and modelling
of concepts represented in each "businessview". A model integrative
infrastructure allows us to develop the prototype and to manage user
interaction through the definition of models' transformations.


title: On Baxter Q-operators And Their Arithmetic Implications

abstract:
  We consider Baxter Q-operators for various versions of quantum affine Toda
chain. The interpretation of eigenvalues of the finite Toda chain Baxter
operators as local Archimedean L-functions proposed recently is generalized to
the case of affine Lie algebras. We also introduce a simple generalization of
Baxter operators and local L-functions compatible with this identification.
This gives a connection of the Toda chain Baxter Q-operators with an
Archimedean version of the Polya-Hilbert operator proposed by Berry-Kitting. We
also elucidate the Dorey-Tateo spectral interpretation of eigenvalues of
Q-operators. Using explicit expressions for eigenfunctions of
affine/relativistic Toda chain we obtain an Archimedean analog of
Casselman-Shalika-Shintani formula for Whittaker function in terms of
characters.


title:
Partially-Time-Ordered Schwinger-Keldysh Loop Expansion of Coherent
  Nonlinear Optical Susceptibilities

abstract:
  A compact correlation-function expansion is developed for nth order optical
susceptibilities in the frequency domain using the Keldysh-Schwinger loop. By
not keeping track of the relative time ordering of bra and ket interactions at
the two branches of the loop, the resulting expressions contain only n+1 basic
terms, compared to the 2n terms required for a fully time-ordered density
matrix description. Superoperator Green's function expressions for the nth
order suscpeptibility derived using both expansions reflect different types of
interferences between pathways .These are demonstrated for correlation-induced
resonances in four wave mixing signals.


title:
On a constrained reaction-diffusion system related to multiphase
  problems

abstract:
  We solve and characterize the Lagrange multipliers of a reaction-diffusion
system in the Gibbs simplex of R^{N+1} by considering strong solutions of a
system of parabolic variational inequalities in R^N. Exploring properties of
the two obstacles evolution problem, we obtain and approximate a N-system
involving the characteristic functions of the saturated and/or degenerated
phases in the nonlinear reaction terms. We also show continuous dependence
results and we establish sufficient conditions of non-degeneracy for the
stability of those phase subregions.


title: On the geometry of the first and second Painlev\'e equations

abstract:
  In this paper we \emph{explicitly} compute the transformation that maps the
generic second order differential equation $y''= f(x, y, y')$ to the Painlev\'e
first equation $y''=6y^2+x$ (resp. the Painlev\'e second equation ${y''=2
y^{3}+yx+ \alpha}$). This change of coordinates, which is function of $f$ and
its partial derivatives, does not exist for every $f$; it is necessary that the
function $f$ satisfies certain conditions that define the equivalence class of
the considered Painlev\'e equation. In this work we won't consider these
conditions and the existence issue is solved \emph{on line} as follows: If the
input equation is known then it suffices to specialize the change of
coordinates on this equation and test by simple substitution if the equivalence
holds. The other innovation of this work lies in the exploitation of discrete
symmetries for solving the equivalence problem.


title: Automorphism Groups of Finite p-Groups: Structure and Applications

abstract:
  This thesis has three goals related to the automorphism groups of finite
$p$-groups. The primary goal is to provide a complete proof of a theorem
showing that, in some asymptotic sense, the automorphism group of almost every
finite $p$-group is itself a $p$-group. We originally proved this theorem in a
paper with Martin; the presentation of the proof here contains omitted proof
details and revised exposition. We also give a survey of the extant results on
automorphism groups of finite $p$-groups, focusing on the order of the
automorphism groups and on known examples. Finally, we explore a connection
between automorphisms of finite $p$-groups and Markov chains. Specifically, we
define a family of Markov chains on an elementary abelian $p$-group and bound
the convergence rate of some of those chains.


title:
Presentations of Finite Simple Groups: Profinite and Cohomological
  Approaches

abstract:
  We prove the following three closely related results. The first is that every
finite simple group has a profinite presentation with 2 generators and at most
18 relations. The second is that if G is a finite simple group, F a field and M
an FG-module, then the dimension of the second cohomology group of G with
coefficients in M is at most 17.5 times the dimension of M. The third result is
that we may replace 17.5 by 18.5 as long as M is faithful irreducible G-module.
These last two results answer conjectures of Holt.


title: Magnetorotational instability in electrically driven fluids

abstract:
  The linear stability of electrically driven flow of liquid metal in circular
channel in the presence of vertical magnetic field is studied. It is shown that
the instability threshold of such flow is determined by magnetorotational
instability of non-axisymmetric modes ($m\neq0$) and does not depend on the
type of the fluid if magnetic Prandtl number is small $\Pr\ll1$. Our numerical
results are found to be in a good agreement with available experimental data
from Grenoble High Magnetic Field Laboratory, France [P. Moresco and T.
Alboussi\`{e}re, J. Fluid Mech. \textbf{504}, 167 (2004)].


title:
A computation of an universal weight function for the quantum affine
  algebra U_q(\hat{\mathfrak{gl}}_N)

abstract:
  We compute an universal weight function (off-shell Bethe vectors) in any
representation with a weight singular vector of the quantum affine algebra
$U_q(\hat{\mathfrak{gl}}_N)$ applying the method of projections of Drinfeld
currents developed in arXiv:math/0610398.


title: p-Adic refinable functions and MRA-based wavelets

abstract:
  We described a wide class of $p$-adic refinable equations generating $p$-adic
multiresolution analysis. A method for the construction of $p$-adic orthogonal
wavelet bases within the framework of the MRA theory is suggested. A
realization of this method is illustrated by an example, which gives a new
3-adic wavelet basis. Another realization leads to the $p$-adic Haar bases
which were known before.


title:
On the universal weight function for the quantum affine algebra
  U_q(\hat{\mathfrak{gl}}_N)

abstract:
  We continue investigation of the universal weight function for the quantum
affine algebra $U_q(\hat{\mathfrak{gl}}_N)$ started in arXiv:math/0610517 and
arXiv:0711.2819. We obtain two recurrence relations for the universal weight
function applying the method of projections developed in arXiv:math/0610398. On
the level of the evaluation representation of $U_q(\hat{\mathfrak{gl}}_N)$ we
reproduce both recurrence relations for the off-shell Bethe vectors calculated
in arXiv:math/0702277 using combinatorial methods.


title: Thermodynamic and quantum entropy gain of frame averaging

abstract:
  We are discussing a universal non-unitary map M subsequent to a generic
unitary map U, whose von Neumann entropy gain coincides with the calculated
thermodynamic entropy production. For many-body quantum reservoirs we prove
that M can be the averaging over all translations of the spatial frame.
Assuming the coincidence of microscopic and macroscopic entropy productions
leads to a novel equation between entropy gain of frame averaging and relative
entropy. Our map M turns out to coincide with the older one called twirl, used
recently in the theory of quantum reference frames. Related results to ours
have been obtained and we discuss some of them briefly. Possible relevance of
frame averaging (twirling) for real world irreversibility is mentioned.

categories: quant-ph cond-mat.stat-mech gr-qc math-ph math.MP


title: Dark matter's X-files

abstract:
  Sterile neutrinos with keV masses can constitute all or part of the
cosmological dark matter. The electroweak-singlet fermions, which are usually
introduced to explain the masses of active neutrinos, need not be heavier than
the electroweak scale; if one of them has a keV-scale mass, it can be the
dark-matter particle, and it can also explain the observed pulsar kicks. The
relic sterile neutrinos could be produced by several different mechanisms. If
they originate primarily from the Higgs decays at temperatures of the order of
100 GeV, the resulting dark matter is much ``colder'' than the warm dark matter
produced in neutrino oscillations. The signature of this form of dark matter is
the spectral line from the two-body decay, which can be detected by the X-ray
telescopes. The same X-rays can have other observable manifestations, in
particular, though their effects on the formation of the first stars.


title: Degrees of Freedom of Wireless X Networks

abstract:
  We explore the degrees of freedom of $M\times N$ user wireless $X$ networks,
i.e. networks of $M$ transmitters and $N$ receivers where every transmitter has
an independent message for every receiver. We derive a general outerbound on
the degrees of freedom \emph{region} of these networks. When all nodes have a
single antenna and all channel coefficients vary in time or frequency, we show
that the \emph{total} number of degrees of freedom of the $X$ network is equal
to $\frac{MN}{M+N-1}$ per orthogonal time and frequency dimension.
Achievability is proved by constructing interference alignment schemes for $X$
networks that can come arbitrarily close to the outerbound on degrees of
freedom. For the case where either M=2 or N=2 we find that the outerbound is
exactly achievable. While $X$ networks have significant degrees of freedom
benefits over interference networks when the number of users is small, our
results show that as the number of users increases, this advantage disappears.
Thus, for large $K$, the $K\times K$ user wireless $X$ network loses half the
degrees of freedom relative to the $K\times K$ MIMO outerbound achievable
through full cooperation. Interestingly, when there are few transmitters
sending to many receivers ($N\gg M$) or many transmitters sending to few
receivers ($M\gg N$), $X$ networks are able to approach the $\min(M,N)$ degrees
of freedom possible with full cooperation on the $M\times N$ MIMO channel.
Similar to the interference channel, we also construct an example of a 2 user
$X$ channel with propagation delays where the outerbound on degrees of freedom
is achieved through interference alignment based on a simple TDMA strategy.


title:
Development of a new analysis technique to measure low radial-order p
  modes in spatially-resolved helioseismic data

abstract:
  In order to take full advantage of the long time series collected by the GONG
and MDI helioseismic projects, we present here an adaptation of the
rotation-corrected $m$-averaged spectrum technique in order to observe low
radial-order solar p modes. Modeled profiles of the solar rotation demonstrated
the potential advantage of such a technique. Here we develop a new analysis
procedure which finds the best estimates of the shift of each $m$ of a given
($n,\ell$) multiplet, commonly expressed as an expansion in a set of orthogonal
polynomials, which yield the narrowest mode in the $m$-averaged spectrum. We
apply the technique to the GONG data for modes with $1 \leq \ell \leq 25$ and
show that it allows us to measure lower-frequency modes than with classic
peak-fitting analysis of the individual-$m$ spectra.


title:
Searching for new homogeneous sine-Gordon theories using T-duality
  symmetries

abstract:
  The Homogeneous sine-Gordon (HSG) theories are integrable perturbations of
$G_k/U(1)^{r_G}$ coset CFTs, where $G$ is a simple compact Lie group of rank
$r_G$ and $k>1$ is an integer. Using their T-duality symmetries, we investigate
the relationship between the different theories corresponding to a given coset,
and between the different phases of a particular theory. Our results suggest
that for $G=SU(n)$ with $n\geq5$ and $E_6$ there could be two non-equivalent
HSG theories associated to the same coset, one of which has not been considered
so far.


title: Quantum secure direct communication based on supervised teleportation

abstract:
  We present a quantum secure direct communication(QSDC) scheme as an extension
for a proposed supervised secure entanglement sharing protocol. Starting with a
quick review on the supervised entanglement sharing protocol -- the "Wuhan"
protocol [Y. Li and Y. Liu, arXiv:0709.1449v2], we primarily focus on its
further extend using for a QSDC task, in which the communication attendant
Alice encodes the secret message directly onto a sequence of 2-level particles
which then can be faithfully teleported to Bob using the shared maximal
entanglement states obtained by the previous "Wuhan" protocol. We also evaluate
the security of the QSDC scheme, where an individual self-attack performed by
Alice and Bob -- the out of control attack(OCA) is introduced and the
robustness of our scheme on the OCA is documented.


title:
Comment on the Alday-Maldacena solution in calculating scattering
  amplitude via AdS/CFT

abstract:
  Following the recent proposal of Alday and Maldacena to obtain the strong
coupling scattering amplitude in N=4 SYM via AdS/CFT, we point out that a
unique solution can be obtained by imposing all the Virasoro constraints. In
the case of four-gluon scattering, this solution is identical to the
Alday-Maldacena solution, which is in accordance with the ansatz of Bern, Dixon
and Smirnov. This also solves the moduli space problem of the four-point
solution in a recent paper of Mironov, Morozov and Tomaras.


title:
Spectral scaling of the Leray-$\alpha$ model for two-dimensional
  turbulence

abstract:
  We present data from high-resolution numerical simulations of the
Navier-Stokes-$\alpha$ and the Leray-$\alpha$ models for two-dimensional
turbulence. It was shown previously (Lunasin et al., J. Turbulence, 8, (2007),
751-778), that for wavenumbers $k$ such that $k\alpha\gg 1$, the energy
spectrum of the smoothed velocity field for the two-dimensional
Navier-Stokes-$\alpha$ (NS-$\alpha$) model scales as $k^{-7}$. This result is
in agreement with the scaling deduced by dimensional analysis of the flux of
the conserved enstrophy using its characteristic time scale. We therefore
hypothesize that the spectral scaling of any $\alpha$-model in the sub-$\alpha$
spatial scales must depend only on the characteristic time scale and dynamics
of the dominant cascading quantity in that regime of scales. The data presented
here, from simulations of the two-dimensional Leray-$\alpha$ model, confirm our
hypothesis. We show that for $k\alpha\gg 1$, the energy spectrum for the
two-dimensional Leray-$\alpha$ scales as $k^{-5}$, as expected by the
characteristic time scale for the flux of the conserved enstrophy of the
Leray-$\alpha$ model. These results lead to our conclusion that the dominant
directly cascading quantity of the model equations must determine the scaling
of the energy spectrum.


title:
Moments of the heavy-quark parton distribution function from QCD sum
  rules

abstract:
  The moments of the heavy quark-parton distribution functions in a heavy
pseudoscalar meson are calculated from QCD sum rules. Expanding these sum rules
in the inverse heavy quark mass we obtain the heavy-mass limits of the moments.
Comparison with the finite mass results reveals that while the heavy mass
expansion works reasonably well for the $b$ quark, one has to take into account
terms of higher than $(1/m_c)^2$ order for the $c$ quark. This result can
provide a quantitative assessment of $c$ and $b$ quark fragmentation models
based on the heavy-quark mass limit.


title:
Discovery of a WZ Sge-Type Dwarf Nova, SDSS J102146.44+234926.3:
  Unprecedented Infrared Activity during a Rebrightening Phase

abstract:
  Several SU UMa-type dwarf novae, in particular, WZ Sge-type stars tend to
exhibit rebrightenings after superoutbursts. The rebrightening phenomenon is
problematic for the disk instability theory of dwarf novae since it requires a
large amount of remnant matter in the disk even after superoutbursts. Here, we
report our optical and infrared observations during the first-ever outburst of
a new dwarf nova, SDSS J102146.44+234926.3. During the outburst, we detected
superhumps with a period of 0.056281 +/- 0.000015 d, which is typical for
superhump periods in WZ Sge stars. In conjunction with the appearance of a
long-lived rebrightening, we conclude that the object is a new member of WZ Sge
stars. Our observations, furthermore, revealed infrared behaviors for the first
time in the rebrightening phase of WZ Sge stars. We discovered prominent
infrared superhumps. We calculate the color temperature of the infrared
superhump source to be 4600-6400 K. These temperatures are too low to be
explained with a fully-ionized disk appearing during dwarf nova outbursts. We
also found a Ks-band excess over the hot disk component. These unprecedented
infrared activities provide evidence for the presence of mass reservoir at the
outermost part of the accretion disk. We propose that a moderately high
mass-accretion rate at this infrared active region leads to the long-lived
rebrightening observed in SDSS J102146.44+234926.3.


title:
Premi\`ere \'etape vers une navigation r\'ef\'erentielle par l'image
  pour l'assistance \`a la conception des ambiances lumineuses

abstract:
  In the first design stage, image reference plays a double role of means of
formulation and resolution of problems. In our approach, we consider image
reference as a support of creation activity to generate ideas and we propose a
tool for navigation in references by image in order to assist daylight ambience
design. Within this paper, we present, in a first part, the semantic indexation
method to be used for the indexation of our image database. In a second part we
propose a synthetic analysis of various modes of referential navigation in
order to propose a tool implementing all or a part of these modes.


title: Characterization of non-degenerate plane curve singularities

abstract:
  We characterize plane curve germes non-degenerate in Kouchnirenko's sense in
terms of characteristics and intersection multiplicities of branches.


title: G-Brownian Motion and Dynamic Risk Measure under Volatility Uncertainty

abstract:
  We introduce a new notion of G-normal distributions. This will bring us to a
new framework of stochastic calculus of Ito's type (Ito's integral, Ito's
formula, Ito's equation) through the corresponding G-Brownian motion. We will
also present analytical calculations and some new statistical methods with
application to risk analysis in finance under volatility uncertainty.
  Our basic point of view is: sublinear expectation theory is very like its
special situation of linear expectation in the classical probability theory.
Under a sublinear expectation space we still can introduce the notion of
distributions, of random variables, as well as the notions of joint
distributions, marginal distributions, etc. A particularly interesting
phenomenon in sublinear situations is that a random variable Y is independent
to X does not automatically implies that X is independent to Y.
  Two important theorems have been proved: The law of large number and the
central limit theorem.


title: Faster Algorithms for Rigidity in the Plane

abstract:
  In [1], a new construction called red-black hierarchy characterizing Laman
graphs and an algorithm for computing it were presented. For a Laman graph
G=(V,E) with n vertices it runs in O(n^2) time assuming that a partition of
(V,E+e) into two spanning trees is given. We show that a simple modification
reduces the running time to O(n\log n). The total running time can be reduced
O(n\sqrt{n\log n}) using the algorithm by Gabow and Westermann [2] for
partitioning a graph into two forests. The existence of a red-black hierarchy
is a necessary and sufficient condition for a graph to be a Laman graph. The
algorithm for constructing a red-black hierarchy can be then modified to
recognize Laman graphs in the same time.


title: Colored Jones polynomials with polynomial growth

abstract:
  The volume conjecture and its generalizations say that the colored Jones
polynomial corresponding to the N-dimensional irreducible representation of
sl(2;C) of a (hyperbolic) knot evaluated at exp(c/N) grows exponentially with
respect to N if one fixes a complex number c near 2*Pi*I. On the other hand if
the absolute value of c is small enough, it converges to the inverse of the
Alexander polynomial evaluated at exp(c). In this paper we study cases where it
grows polynomially.


title:
Neutron-proton bremsstrahlung from intermediate energy heavy-ion
  reactions as a probe of the nuclear symmetry energy?

abstract:
  Hard photons from neutron-proton bremsstrahlung in intermediate energy
heavy-ion reactions are examined as a potential probe of the nuclear symmetry
energy within a transport model. Effects of the symmetry energy on the yields
and spectra of hard photons are found to be generally smaller than those due to
the currently existing uncertainties of both the in-medium nucleon-nucleon
cross sections and the photon production probability in the elementary process
$pn\to pn\gamma$. Very interestingly, nevertheless, the ratio of hard photon
spectra $R_{1/2}(\gamma)$ from two reactions using isotopes of the same element
is not only approximately independent of these uncertainties but also quite
sensitive to the symmetry energy. For the head-on reactions of
$^{132}Sn+^{124}Sn$ and $^{112}Sn+^{112}Sn$ at $E_{beam}/A=50$ MeV, for
example, the $R_{1/2}(\gamma)$ displays a rise up to 15% when the symmetry
energy is reduced by about 20% at $\rho=1.3\rho_0$ which is the maximum density
reached in these reactions.


title: Graded Sparse Graphs and Matroids

abstract:
  Sparse graphs and their associated matroids play an important role in
rigidity theory, where they capture the combinatorics of generically rigid
structures. We define a new family called {\bf graded sparse graphs}, arising
from generically pinned (completely immobilized) bar-and-joint frameworks and
prove that they also form matroids.
  We address five problems on graded sparse graphs: {\bf Decision}, {\bf
Extraction}, {\bf Components}, {\bf Optimization}, and {\bf Extension}. We
extend our {\bf pebble game algorithms} to solve them.