title: Single Particle Tunneling in Strongly Driven Double Well Potentials

abstract:
  We report on the first direct observation of coherent control of single
particle tunneling in a strongly driven double well potential. In our setup
atoms propagate in a periodic arrangement of double wells allowing the full
control of the driving parameters such as frequency, amplitude and even the
space-time symmetry. Our experimental findings are in quantitative agreement
with the predictions of the corresponding Floquet theory and are also compared
to the predictions of a simple two mode model. Our experiments reveal directly
the critical dependence of coherent destruction of tunneling on the generalized
parity symmetry.


title: Stability of thermal structures with an internal heating source

abstract:
  We study the thermal equilibrium and stability of isobaric, spherical
structures having a radiation source located at its center. The thermal
conduction coefficient, external heating and cooling rates are represented as
power laws of the temperature. The internal heating decreases with distance
from the source r approximately as exp(-tau)/(r**2), being tau the optical
depth. We find that the influence of the radiation source is important only in
the central region, but its effect is enough to make the system thermally
unstable above a certain threshold central temperature. This threshold
temperature decreases as the internal heating efficiency increases, but,
otherwise, it does not depend on the structure size. Our results suggest that a
solar-like star migrating into a diffuse interstellar region may destabilize
the surrounding medium.


title: Laplaza Sets, or How to Select Coherence Diagrams for Pseudo Algebras

abstract:
  We define a general concept of pseudo algebras over theories and 2-theories.
A more restrictive such notion was introduced by Hu and Kriz, but as noticed by
M. Gould, did not capture the desired examples. The approach taken in this
paper corrects the mistake by introducing a more general concept, allowing more
flexibility in selecting coherence diagrams for pseudo algebras.


title:
Real space tests of the statistical isotropy and Gaussianity of the WMAP
  CMB data

abstract:
  ABRIDGED: We introduce and analyze a method for testing statistical isotropy
and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature
maps, and cross-channel difference maps. We divide the sky into regions of
varying size and shape and measure the first four moments of the one-point
distribution within these regions, and using their simulated spatial
distributions we test the statistical isotropy and Gaussianity hypotheses. By
randomly varying orientations of these regions, we sample the underlying CMB
field in a new manner, that offers a richer exploration of the data content,
and avoids possible biasing due to a single choice of sky division. The
statistical significance is assessed via comparison with realistic Monte-Carlo
simulations.
  We find the three-year WMAP maps to agree well with the isotropic, Gaussian
random field simulations as probed by regions corresponding to the angular
scales ranging from 6 deg to 30 deg at 68% confidence level. We report a
strong, anomalous (99.8% CL) dipole ``excess'' in the V band of the three-year
WMAP data and also in the V band of the WMAP five-year data (99.3% CL). We
notice the large scale hemispherical power asymmetry, and find that it is not
highly statistically significant in the WMAP three-year data (<~ 97%) at scales
l <= 40. The significance is even smaller if multipoles up to l=1024 are
considered (~90% CL). We give constraints on the amplitude of the
previously-proposed CMB dipole modulation field parameter. We easily detect the
residual foregrounds in cross-band difference maps at rms level <~ 7 \mu K (at
scales >~ 6 deg) and limit the systematical uncertainties to <~ 1.7 \mu K (at
scales >~ 30 deg).


title: Hawking radiation of Dirac particles via tunneling from Kerr black hole

abstract:
  We investigated Dirac Particles' Hawking radiation from event horizon of Kerr
black hole in terms of the tunneling formalism. Applying WKB approximation to
the general covariant Dirac equation in Kerr spacetime background, we obtain
the tunneling probability for fermions and Hawking temperature of Kerr black
hole. The result obtained by taking the fermion tunneling into account is
consistent with the previous literatures.


title:
CHARA Array Measurements of the Angular Diameters of Exoplanet Host
  Stars

abstract:
  We have measured the angular diameters for a sample of 24 exoplanet host
stars using Georgia State University's CHARA Array interferometer. We use these
improved angular diameters together with Hipparcos parallax measurements to
derive linear radii and to estimate the stars' evolutionary states.


title:
A Wide-area VLA Continuum Survey near the Galactic Center at 6 and 20 cm
  Wavelengths

abstract:
  We describe the results of a mJy-sensitivity, VLA survey of roughly 1 square
degree near the Galactic center at 6 and 20 cm. Catalogs of compact and
filamentary structures are given and compared to previous surveys of the
region. Eight of the unusual, nonthermal radio filaments are detected in 6 cm
polarized emission; three of these are the first such detections, confirming
their nonthermal nature. This survey found emission from a filament at
(l,b)=(359.1,0.75), or a projected distance from Sgr A* of 200 pc, greatly
extending the latitude range observed with such features. There is also new
evidence for spatial gradients in the 6/20 cm spectral indices of some
filaments and we discuss models for these gradients. In studying compact
sources, the combination of spectral index and polarization information allows
us to identify pulsar candidates and compact HII regions in the survey. There
is also some evidence that the flux measurements of compact sources may be
affected by electron scattering from the interstellar medium in the cent ral
few hundred parsecs of the Galaxy.


title:
On some transformations of bilateral birth-and-death processes with
  applications

abstract:
  A method yielding simple relationships among bilateral birth-and-death
processes is outlined. This allows one to relate birth and death rates of two
processes in such a way that their transition probabilities, first-passage-time
densities and ultimate crossing probabilities are mutually related by some
product-form expressions.


title: Mass effects and four-particle amplitudes at the two-loop level in QCD

abstract:
  I review the recent progress in the evaluation of two-loop massive QCD
amplitudes necessary for the description of hadronic scattering processes at
the LHC. I put a special emphasis on the case of top-quark final states.


title:
Doping Dependence of Two Energy Scales in the Tunneling Spectra of
  Superconducting La$_{2-x}$Sr$_{x}$CuO$_{4}$

abstract:
  Scanning tunneling microscopy and spectroscopy have been performed on
superconducting La$_{2-x}$Sr$_{x}$CuO$_{4}$ ($x=0.06, 0.12, 0.16$, and 0.21) at
4.2 K. Atomically resolved surface topography has been observed on the $ab$
surface, which exhibits a one-dimensional structure corresponding to the
buckling pattern of the orthorhombic phase. The tunneling spectra of all
samples exhibit kinks at about $\pm 5$ meV in addition to the energy gap,
indicating the existence of two energy scales. While the gap magnitude varies
on the length scale of a few nm and steadily increases upon underdoping, the
kink energy is spatially uniform on the surface and almost independent of the
doping level.


title: New formulas for Stirling-like numbers and Dobinski-like formulas

abstract:
  Extensions of the $Stirling$ numbers of the second kind and $Dobinski$ -like
formulas are proposed in a series of exercises for graduates. Some of these new
formulas recently discovered by me are to be found in the source paper $ [1]$.
These extensions naturally encompass the well known $q$- extensions. The
indicatory references are to point at a part of the vast domain of the
foundations of computer science in arxiv affiliation.


title:
Characterization of mammographic masses using a gradient-based
  segmentation algorithm and a neural classifier

abstract:
  The computer-aided diagnosis system we developed for the mass
characterization is mainly based on a segmentation algorithm and on the neural
classification of several features computed on the segmented mass. Mass
segmentation plays a key role in most computerized systems. Our technique is a
gradient-based one, showing the main characteristic that no free parameters
have been evaluated on the dataset used in this analysis, thus it can directly
be applied to datasets acquired in different conditions without any ad-hoc
modification. A dataset of 226 masses (109 malignant and 117 benign) has been
used in this study. The segmentation algorithm works with a comparable
efficiency both on malignant and benign masses. Sixteen features based on
shape, size and intensity of the segmented masses are analyzed by a
multi-layered perceptron neural network. A feature selection procedure has been
carried out on the basis of the feature discriminating power and of the linear
correlations interplaying among them. The comparison of the areas under the ROC
curves obtained by varying the number of features to be classified has shown
that 12 selected features out of the 16 computed ones are powerful enough to
achieve the best classifier performances. The radiologist assigned the
segmented masses to three different categories: correctly-, acceptably- and
non-acceptably-segmented masses. We initially estimated the area under ROC
curve only on the first category of segmented masses (the 88.5% of the
dataset), then extending the dataset to the second sub-class (reaching the
97.8% of the dataset) and finally to the whole dataset, obtaining Az =
0.805+-0.030, 0.787+-0.024 and 0.780+-0.023, respectively.


title: Quantum learning by measurement and feedback

abstract:
  We propose an approach to quantum computing in which quantum gate strengths
are parametrized by quantum degrees of freedom, and the capability of the
quantum computer to perform desired tasks is monitored and gradually improved
by successive feedback modifications of the coupling strength parameters. Our
proposal aims at experimental implementation, scalable to computational
problems too large to be simulated theoretically, and we demonstrate
feasibility of our proposal with simulations on search and factoring
algorithms.


title: TeV-photon paradox and space with SU(2) fuzziness

abstract:
  The possibility is examined that a model based on space noncommutativity of
linear type can explain why photons from distant sources with multi-TeV
energies can reach earth. In particular within a model in which space
coordinates satisfy the algebra of SU(2) Lie group, it is shown that there is
the possibility that the pair production through the reaction of CMB and
energetic photons would be forbidden kinematically.


title: Multi-imaging and Bayesian estimation for photon counting with EMCCD's

abstract:
  A multi-imaging strategy is proposed and experimentally tested to improve the
accuracy of photon counting with an electron multiplying charge-coupled device
(EMCCD), by taking into account the random nature of its on-chip gain and the
possibility of multiple photo-detection events on one pixel. This strategy is
based on Bayesian estimation on each image, with a priori information given by
the sum of the images. The method works even for images with large dynamic
range, with more improvement in the low light level areas. In these areas, two
thirds of the variance added by the EMCCD in a conventional imaging mode are
removed, making the physical photon noise predominant in the detected image.


title:
Infinitesimal or cocommutative dipterous bialgebras and good triples of
  operads

abstract:
  The works of Poincare, Birkhoff, Witt and Cartier, Milnor, Moore on the
connected cocommutative Hopf algebras translated in the language of operads
means that the triple of operads (Com, As, Lie) endowed with the Hopf
compatiblity relation is good. In this paper, we focus on left dipterous (resp.
right dipterous) algebras which are associative algebras with an extra left
(resp. right) module on themselves and look for good triples were $As$ is
replaced by the dipterous operad Dipt. Since the work of Loday and Ronco, the
triple of operads (As, Dipt, B_\infty) endowed with the semi-Hopf compatibility
relations is known to be good. In this paper, we prove that the triple of
operads (As, Dipt, Grove) endowed with the so-called (nonunital)
semi-infinitesimal compatibility relations is good. For that, explicit
constructions of the free dipterous algebra and the free grove-algebra over a
K-vector space V are given. These constructions turn out to be related to
rooted planar trees and the little an large Schroeder numbers. Many examples of
dipterous algebras are given, notably the free L-dipterous algebras. As a
corollary of our results, we also recover that the triple of operads (2As,
Dipt, Vect) endowed both with the unital semi-Hopf and with the unital
semi-infinitesimal compatibility relations is good, where 2As denotes the
operad of 2-associative algebras. We also open this paper on a good triple,
related to the Connes-Kreimer Hopf algebra in quantum field theory, (Com, Dipt,
Prim_{Com} Dipt) endowed with the Hopf compatibility relations and also present
a general theorem giving good triples from entangled dipterous like operads
named associative molecules.


title: Flavor mixing in a Lee-type model

abstract:
  An exactly solvable Quantum Field Theory (QFT) model of Lee-type is
constructed to study how neutrino flavor eigenstates are created through
interactions and how the localization properties of neutrinos follows from the
parent particle that decays. The two-particle states formed by the neutrino and
the accompanying charged lepton can be calculated exactly as well as their
creation probabilities. We can show that the coherent creation of neutrino
flavor eigenstates follows from the common negligible contribution of neutrino
masses to their creation probabilities. On the other hand, it is shown that it
is not possible to associate a well defined "flavor" to mixed states of charged
leptons.


title:
Four point function of R-currents in N=4 SYM in the Regge limit at weak
  coupling

abstract:
  We compute, in N=4 super Yang-Mills theory, the four point correlation
function of R-currents in the Regge limit in the leading logarithmic
approximation at weak coupling. Such a correlator is the closest analog to
photon-photon scattering within QCD, and there is a well-defined procedure to
perform the analogous computation at strong coupling via the AdS/CFT
correspondence. The main result of this paper is, on the gauge theory side, the
proof of Regge factorization and the explicit computation of the R-current
impact factors.


title:
Comment on 'Time-energy uncertainty relations for neutrino oscillations
  and the Mossbauer neutrino experiment'

abstract:
  We discuss the implications of the time-energy uncertainty relation to
recoillessly emitted and captured neutrinos (Mossbauer neutrinos) and show that
it does not preclude oscillations of these neutrinos, contrary to a recent
claim (J. Phys. G35 (2008) 095003, arXiv:0803.0527).


title:
Nonlocal symmetries of integrable two-field divergent evolutionary
  systems

abstract:
  Nonlocal symmetries for exactly integrable two-field evolutionary systems of
the third order have been computed. Differentiation of the nonlocal symmetries
with respect to spatial variable gives a few nonevolutionary systems for each
evolutionary system. Zero curvature representations for some new nonevolution
systems are presented.


title: Bases in Lie and Quantum Algebras

abstract:
  Applications of algebras in physics are related to the connection of
measurable observables to relevant elements of the algebras, usually the
generators. However, in the determination of the generators in Lie algebras
there is place for some arbitrary conventions. The situation is much more
involved in the context of quantum algebras, where inside the quantum universal
enveloping algebra, we have not enough primitive elements that allow for a
privileged set of generators and all basic sets are equivalent. In this paper
we discuss how the Drinfeld double structure underlying every simple Lie
bialgebra characterizes uniquely a particular basis without any freedom,
completing the Cartan program on simple algebras. By means of a perturbative
construction, a distinguished deformed basis (we call it the analytical basis)
is obtained for every quantum group as the analytical prolongation of the above
defined Lie basis of the corresponding Lie bialgebra. It turns out that the
whole construction is unique, so to each quantum universal enveloping algebra
is associated one and only one bialgebra. In this way the problem of the
classification of quantum algebras is moved to the classification of
bialgebras. In order to make this procedure more clear, we discuss in detail
the simple cases of su(2) and su_q(2).


title:
Exact Results on Dynamical Decoupling by $\pi$-Pulses in Quantum
  Information Processes

abstract:
  The aim of dynamical decoupling consists in the suppression of decoherence by
appropriate coherent control of a quantum register. Effectively, the
interaction with the environment is reduced. In particular, a sequence of $\pi$
pulses is considered. Here we present exact results on the suppression of the
coupling of a quantum bit to its environment by optimized sequences of $\pi$
pulses. The effect of various cutoffs of the spectral density of the
environment is investigated. As a result we show that the harder the cutoff is
the better an optimized pulse sequence can deal with it. For cutoffs which are
neither completely hard nor very soft we advocate iterated optimized sequences.


title: A Note on Coseparable Coalgebras

abstract:
  Given a coalgebra $C$ over a commutative ring $R,$ we show that $C$ can be
considered as a (not necessarily counital) $C^{\ast op}$-coring. Moreover, we
show that this coring has a left (right) counity if and only if $C$ is
coseparable as an $R$-coalgebra.


title:
Fluctuation theorem for the renormalized entropy change in the strongly
  nonlinear nonequilibrium regime

abstract:
  Generalizing a recent work [T. Taniguchi and E. G. D. Cohen, J. Stat. Phys.
126, 1 (2006)] that was based on the Onsager-Machlup theory, a nonlinear
relaxation process is considered for a macroscopic thermodynamic quantity. It
is found that the fluctuation theorem holds in the nonlinear nonequilibrium
regime if the change of the entropy characterized by local equilibria is
appropriately renormalized. The fluctuation theorem for the ordinary entropy
change is recovered in the linear near-equilibrium case. This result suggests a
possibility that the the information-theoretic entropy of the Shannon form may
be modified in the strongly nonlinear nonequilibrium regime.


title:
The thermostatistical aspect of Werner-type states and quantum
  entanglement

abstract:
  A general Werner-type state is studied from two viewpoints: (i) an
application of dynamical interaction of the objective system with its
environment, represented by a unital positive operator-valued measure (POVM),
which ensures increase of entropy, makes the system evolve from an initial pure
state to a mixed state of the Werner type, and (ii) the space of the objective
system is constrained to have a given value of the fidelity. Then, the maximum
entropy principle is shown to yield the Werner-type state as a canonical
ensemble with the projector Hamiltonian. This novel observation is illustrated
by examples of bipartite systems, the separability criteria on which are given
in terms of the values of temperature. The present viewpoint may cast light on
relevance of thermostatistics to the physics of quantum entanglement. In
addition, the POVM scheme presented here offers a way of experimentally
generating the Werner-type thermal states.


title: Distribution Function of Dark Matter with Constant Anisotropy

abstract:
  N-body simulations of dark matter halos show that the density is cusped near
the center of the halo. The density profile behaves as $r^{-\gamma}$ in the
inner parts, where $\gamma \simeq 1$ for the NFW model and $\gamma \simeq 1.5$
for the Moore's model, but in the outer parts, both models agree with each
other in the asymptotic behavior of the density profile. The simulations also
show the information about anisotropy parameter $\beta(r)$ of velocity
distribution. $\beta\approx 0$ in the inner part and $\beta\approx 0.5$
(radially anisotropic) in the outer part of the halo. We provide some
distribution functions $F(E,L)$ with the constant anisotropy parameter $\beta$
for the two spherical models of dark matter halos: a new generalized NFW model
and a generalized Moore model. There are two parameters $\alpha$ and $\epsilon$
for those two generalized models to determine the asymptotic behavior of the
density profile. In this paper, we concentrate on the situation of
$\beta(r)=1/2$ from the viewpoint of the simulation.


title: GINS: a new tool for VLBI Geodesy and Astrometry

abstract:
  In the framework of the "Groupe de Recherches de G\'eod\'esie Spatiale"
(GRGS), a rigorous combination of the data from five space geodetic techniques
(VLBI, GPS, SLR, LLR and DORIS) is routinely applied to simultaneously
determine a Terrestrial Reference Frame (TRF) and Earth Orientation Parameters
(EOP). This analysis is conducted with the software package GINS which has the
capability to process data from all five techniques together. Such a
combination at the observation level should ultimately facilitate fine
geophysical studies of the global Earth system. In this project, Bordeaux
Observatory is in charge of the VLBI data analysis, while satellite geodetic
data are processed by other groups. In this paper, we present (i) details about
the VLBI analysis undertaken with GINS, and (ii) the results obtained for the
EOP during the period 2005-2006. We also compare this EOP solution with the IVS
(International VLBI Service for geodesy and astrometry) analysis coordinator
combined results. The agreement is at the 0.2 mas level, comparable to that of
the other IVS analysis centers, which demonstrates the capability of the GINS
software for VLBI analysis.


title:
VLBI analyses with the GINS software for multi-technique combination at
  the observation level

abstract:
  A rigorous approach to simultaneously determine a Terrestrial Reference Frame
(TRF) and Earth Orientation Parameters (EOP) is now currently applied on a
routine basis in a coordinated project within the Groupe de Recherches de
G\'eod\'esie Spatiale (GRGS) in France. Observations of the various space
geodetic techniques (VLBI, SLR, LLR, DORIS and GPS) are separately processed by
different analysis centers with the software package GINS-DYNAMO, developed and
maintained at the GRGS/CNES (Toulouse). This project is aimed at facilitating
fine geophysical analyses of the global Earth system (GGOS project). In this
framework, Bordeaux Observatory is in charge of the VLBI (Very Long Baseline
Interferometry) analyses with GINS for combination with the data of the other
space geodetic techniques at the observation level. In this paper, we present
(i) the analyses undertaken with this new VLBI software, and (ii) the results
obtained for the EOP from beginning 2005 until 2007. Finally, we compare this
EOP solution with the IVS (International VLBI Service) Analysis Coordinator
combined results. The agreement is at the 0.2 mas level, comparable to that of
the other IVS Analysis Centers, which demonstrates the VLBI capability of the
GINS software.


title: Experimental unsaturated soil mechanics

abstract:
  In this general report, experimental systems and procedures of investigating
the hydro-mechanical behaviour of unsaturated soils are presented. The water
retention properties of unsaturated soils are commented and linked to various
physical parameters and properties of the soils. Techniques of controlling
suction are described together with their adaptation in various laboratory
testing devices. Some typical features of the mechanical behaviour of
unsaturated soils are presented within an elasto-plastic framework. An attempt
to describe the numerous and significant recent advances in the investigation
of the behaviour of unsaturated soils, including the contributions to this
Conference, is proposed.


title: Geotechnical problems related with loess deposits in Northern France

abstract:
  Special problems were encountered in some areas in Northern France where the
high speed railways (TGV Nord) crossed some loess deposits that appeared to be
specially sensitive to change in water content and susceptible to collapse.
Numerous sinkholes appeared along some sections of the line following wet
climatic periods. After a general geological and geotechnical presentation of
loess deposits and collapse susceptibility, in which some tools of the
mechanics of unsaturated soils are reconsidered with special application to
loess collapsibility, this paper describes the results of a geotechnical study
carried out on block samples of intact loess. Collapse susceptibility is
examined in the light of microstructure observation. The dependence of collapse
to water content changes is examined and the validity of various existing
collapse criteria is investigated.


title: Mass transport generated by a flow of Gauss maps

abstract:
  Let $A \subset \mathbb{R}^d$, $d\ge 2$, be a compact convex set and let $\mu
= \varrho_0 dx$ be a probability measure on $A$ equivalent to the restriction
of Lebesgue measure. Let $\nu = \varrho_1 dx$ be a probability measure on $B_r
:= \{x\colon |x| \le r\}$ equivalent to the restriction of Lebesgue measure. We
prove that there exists a mapping $T$ such that $\nu = \mu \circ T^{-1}$ and $T
= \phi \cdot {\rm n}$, where $\phi\colon A \to [0,r]$ is a continuous potential
with convex sub-level sets and ${\rm n}$ is the Gauss map of the corresponding
level sets of $\phi$. Moreover, $T$ is invertible and essentially unique. Our
proof employs the optimal transportation techniques. We show that in the case
of smooth $\phi$ the level sets of $\phi$ are driven by the Gauss curvature
flow $\dot{x}(s) = -s^{d-1} \frac{\varrho_1(s {\rm n})}{\varrho_0(x)} K(x)
\cdot {\rm n}(x)$, where $K$ is the Gauss curvature. As a by-product one can
reprove the existence of weak solutions of the classical Gauss curvature flow
starting from a convex hypersurface.


title: X-ray photon correlation spectroscopy under flow

abstract:
  X-ray photon correlation spectroscopy was used to probe the diffusive
dynamics of colloidal particles in a shear flow. Combining X-ray techniques
with microfluidics is an experimental strategy that reduces the risk of x-ray
induced beam damage and also allows time-resolved studies of processes taking
place in flowcells. The experimental results and theoretical predictions
presented here, show that in the low shear limit, for a ``transverse flow''
scattering geometry (scattering wave vector q perpendicular to the direction of
flow) the measured relaxation times are independent of the flow rate and
determined only by the diffusive motion of the particles. This is not generally
valid and in particular, for a ``longitudinal flow'' (q || flow) scattering
geometry, the relaxation times are strongly affected by the flow-induced motion
of the particles. Our results show that the Brownian diffusion of colloidal
particles can be measured in a flowing sample and that, up to flux limitations,
the experimental conditions under which this is possible are easier to achieve
at higher values of q.


title: Gomez's Hamburger (IRAS 18059-3211): A pre main-sequence A-type star

abstract:
  We study the nature of Gomez's Hamburger (IRAS 18059-3211), a nebula that has
been proposed to be a post-AGB object. Such a classification is not confirmed;
instead, we argue that it will be a key object in the study of disks rotating
around young stars.
  We present high resolution SMA maps of CO J=2--1 in Gomez's Hamburger. The
data are analyzed by means of a code that simulates the emission of a nebula
showing a variety of physical conditions and kinematics.
  Our observations clearly show that the CO emitting gas in Gomez's Hamburger
forms a spectacular disk in keplerian rotation. Model calculations undoubtly
confirm this result. The central (mainly stellar) mass is found to be high, ~ 4
Mo for a distance of 500 pc. The mass and (relatively low) luminosity of the
source are, independent of the assumed distance, very different from those
possible in evolved stars. Gomez's Hamburger is probably a transitional object
between the pre-MS and MS phases, still showing interstellar material around
the central star or stellar system.


title: R-matrix approach to integrable systems on time scales

abstract:
  A general unifying framework for integrable soliton-like systems on time
scales is introduced. The $R$-matrix formalism is applied to the algebra of
$\delta$-differential operators in terms of which one can construct infinite
hierarchy of commuting vector fields. The theory is illustrated by two
infinite-field integrable hierarchies on time scales which are difference
counterparts of KP and mKP. The difference counterparts of AKNS and Kaup-Broer
soliton systems are constructed as related finite-field restrictions.


title: X-ray absorption in distant type II QSOs

abstract:
  We present the results of the X-ray spectral analysis of an
XMM-Newton-selected type II QSO sample with z>0.5 and 0.5-10 keV flux of 0.3-33
x 10^{-14} erg/s/cm^2. The distribution of absorbing column densities in type
II QSOs is investigated and the dependence of absorption on X-ray luminosity
and redshift is studied.
  We inspected 51 spectroscopically classified type II QSO candidates from the
XMM-Newton Marano field survey, the XMM-Newton-2dF wide angle survey (XWAS),
and the AXIS survey to set-up a well-defined sample with secure optical type II
identifications. Fourteen type II QSOs were classified and an X-ray spectral
analysis performed. Since most of our sources have only ~40 X-ray counts
(PN-detector), we carefully studied the fit results of the simulated X-ray
spectra as a function of fit statistic and binning method. We determined that
fitting the spectra with the Cash-statistic and a binning of minimum one count
per bin recovers the input values of the simulated X-ray spectra best. Above
100 PN counts, the free fits of the spectrum's slope and absorbing hydrogen
column density are reliable.
  We find only moderate absorption (N_H=(2-10) x 10^22 cm^-2) and no obvious
trends with redshift and intrinsic X-ray luminosity. In a few cases a
Compton-thick absorber cannot be excluded. Two type II objects with no X-ray
absorption were discovered. We find no evidence for an intrinsic separation
between type II AGN and high X-ray luminosity type II QSO in terms of
absorption. The stacked X-ray spectrum of our 14 type II QSOs shows no iron
K-alpha line. In contrast, the stack of the 8 type II AGN reveals a very
prominent iron K-alpha line at an energy of ~ 6.6 keV and an EW ~ 2 keV.


title: Multimode Radiative beta Cephei and delta Cephei Models

abstract:
  As a by-product of beta Cephei and delta Cephei radiative model surveys we
have found interesting cases of multimode pulsation. In case of beta Cephei
stars, we found two multimode domains with two or three modes being involved.
The origin of the multimode pulsation can be traced to one of the two different
mechanisms: either to the non-resonant coupling of the two excited modes
(double-mode pulsation) or to the 2omega_1 = omega_0 + omega_2 parametric
resonance (triple-mode pulsation). In case of delta Cephei models, a
triple-mode pulsation domain, connected with the 2:1 resonance, 2omega_0 =
omega_2, is found. These models are of theoretical interest only, since they do
not obey a proper mass-luminosity relation.


title:
Classical Disordered Ground States: Super-Ideal Gases, and Stealth and
  Equi-Luminous Materials

abstract:
  Using a collective coordinate numerical optimization procedure, we construct
ground-state configurations of interacting particle systems in various space
dimensions so that the scattering of radiation exactly matches a prescribed
pattern for a set of wave vectors. We show that the constructed ground states
are, counterintuitively, disordered (i.e., possess no long-range order) in the
infinite-volume limit. We focus on three classes of configurations with unique
radiation scattering characteristics: (i)``stealth'' materials, which are
transparent to incident radiation at certain wavelengths; (ii)``super-ideal''
gases, which scatter radiation identically to that of an ensemble of ideal gas
configurations for a selected set of wave vectors; and (iii)``equi-luminous''
materials, which scatter radiation equally intensely for a selected set of wave
vectors. We find that ground-state configurations have an increased tendency to
contain clusters of particles as one increases the prescribed luminosity.
Limitations and consequences of this procedure are detailed.


title: Lexical growth, entropy and the benefits of networking

abstract:
  If each node of an idealized network has an equal capacity to efficiently
exchange benefits, then the network's capacity to use energy is scaled by the
average amount of energy required to connect any two of its nodes. The scaling
factor equals \textit{e}, and the network's entropy is $\ln(n)$. Networking
emerges in consequence of nodes minimizing the ratio of their energy use to the
benefits obtained for such use, and their connectability. Networking leads to
nested hierarchical clustering, which multiplies a network's capacity to use
its energy to benefit its nodes. Network entropy multiplies a node's capacity.
For a real network in which the nodes have the capacity to exchange benefits,
network entropy may be estimated as $C \log_L(n)$, where the base of the log is
the path length $L$, and $C$ is the clustering coefficient. Since $n$, $L$ and
$C$ can be calculated for real networks, network entropy for real networks can
be calculated and can reveal aspects of emergence and also of economic,
biological, conceptual and other networks, such as the relationship between
rates of lexical growth and divergence, and the economic benefit of adding
customers to a commercial communications network. \textit{Entropy dating} can
help estimate the age of network processes, such as the growth of hierarchical
society and of language.


title: Cosmic rays through the Higgs portal

abstract:
  We consider electroweak singlet dark matter with a mass comparable to the
Higgs mass. The singlet is assumed to couple to standard matter through a
perturbative coupling to the Higgs particle. The annihilation of a singlet with
a mass comparable to the Higgs mass is dominated by proximity to the W, Z and
Higgs peaks in the annihilation cross section. We find that the continuous
photon spectrum from annihilation of a perturbatively coupled singlet in the
galactic halo can reach a level of several per mil of the EGRET diffuse gamma
ray flux.


title:
Distributed Joint Source-Channel Coding on a Multiple Access Channel
  with Side Information

abstract:
  We consider the problem of transmission of several distributed sources over a
multiple access channel (MAC) with side information at the sources and the
decoder. Source-channel separation does not hold for this channel. Sufficient
conditions are provided for transmission of sources with a given distortion.
The source and/or the channel could have continuous alphabets (thus Gaussian
sources and Gaussian MACs are special cases). Various previous results are
obtained as special cases. We also provide several good joint source-channel
coding schemes for a discrete/continuous source and discrete/continuous
alphabet channel. Channels with feedback and fading are also considered.
  Keywords: Multiple access channel, side information, lossy joint
source-channel coding, channels with feedback, fading channels.


title: Mechanical unfolding and refolding pathways of ubiquitin

abstract:
  Mechanical unfolding and refolding of ubiquitin are studied by Monte Carlo
simulations of a Go model with binary variables. The exponential dependence of
the time constants on the force is verified, and folding and unfolding lengths
are computed, with good agreement with experimental results. Furthermore, the
model exhibits intermediate kinetic states, as observed in experiments.
Unfolding and refolding pathways and intermediate states, obtained by tracing
single secondary structure elements, are consistent with simulations of
previous all-atom models and with the experimentally observed step sizes.


title:
Quantum computation, quantum state engineering, and quantum phase
  transitions driven by dissipation

abstract:
  We investigate the computational power of creating steady-states of quantum
dissipative systems whose evolution is governed by time-independent and local
couplings to a memoryless environment. We show that such a model allows for
efficient universal quantum computation with the result of the computation
encoded in the steady state. Due to the purely dissipative nature of the
process, this way of doing quantum computation exhibits some inherent
robustness and defies some of the DiVincenzo criteria for quantum computation.
We show that there is a natural class of problems that can be solved with such
a model - the preparation of ground states of frustration free quantum
Hamiltonians. This allows for robust and efficient creation of exotic states
that exhibit features like topological quantum order and the creation of PEPS
and it proves the existence of novel dissipative phase transitions. In
particular the latter can in principle be verified experimentally with present
day technology such as with optical lattices.


title:
Mobility of O$_2^-$ ions in supercritical Ar: Experiment and Molecular
  Dynamics Simulations

abstract:
  A new analysis and new Molecular Dynamics (MD) simulations of the
measurements of the mobility $\mu_{i}$ of O$_{2}^{-} $ ions in dense
supercritical Ar gas are reported. $\mu_{i}$ shows a marked dependence on the
distance from the critical temperature $T_{c}.$ A mobility defect appears as a
function of the gas density and its maximum value occurs below the critical
density. The locus of points of maximum mobility defect in the $P-T$ plane
appears on the extrapolation of the coexistence curve into the single-phase
region. MD simulations quantitatively reproduce the mobility defect near
$T_{c}.$


title: Kinetic Mixing of the Photon with Hidden U(1)s in String Phenomenology

abstract:
  Embeddings of the standard model in type II string theory typically contain a
variety of U(1) gauge factors arising from D-branes in the bulk. In general,
there is no reason why only one of these - the one corresponding to weak
hypercharge - should be massless. Observations require that standard model
particles must be neutral (or have an extremely small charge) under additional
massless U(1)s, i.e. the latter have to belong to a so called hidden sector.
The exchange of heavy messengers, however, can lead to a kinetic mixing between
the hypercharge and the hidden-sector U(1)s, that is testable with near future
experiments. This provides a powerful probe of the hidden sectors and, as a
consequence, of the string theory realisation itself. In the present paper, we
show, using a variety of methods, how the kinetic mixing can be derived from
the underlying type II string compactification, involving supersymmetric and
nonsupersymmetric configurations of D-branes, both in large volumes and in
warped backgrounds with fluxes. We first demonstrate by explicit example that
kinetic mixing occurs in a completely supersymmetric set-up where we can use
conformal field theory techniques. We then develop a supergravity approach
which allows us to examine the phenomenon in more general backgrounds, where we
find that kinetic mixing is natural in the context of flux compactifications.
We discuss the phenomenological consequences for experiments at the low-energy
frontier, searching for signatures of light, sub-electronvolt or even massless
hidden-sector U(1) gauge bosons and minicharged particles.


title: DAFNE Interaction Regions upgrade

abstract:
  DAFNE, the Frascati F-factory, has recently completed experimental runs for
the three main detectors, KLOE, FINUDA and DEAR achieving 1.6x10E+32 cm-2s-1
peak and 10 pb-1 daily integrated luminosities. Improving these results by a
significant factor requires changing the collision scheme. For this reason, in
view of the SIDDHARTA detector installation, relevant modifications of the
machine have been realized, aimed at implementing a new collision scheme based
on a large Piwinski angle and crab-waist, together with several other hardware
modifications involving injection kickers, bellows and beam pipe sections.


title: Standard Model Higgs Searches

abstract: The status and perspectives of Standard Model Higgs searches are discussed.


title: On geometry of the Lagrangian description of ideal fluids

abstract:
  The Euler equation for an inviscid, incompressible fluid in a
three-dimensional domain M implies that the vorticity is a frozen-in field.
This can be used to construct a symplectic structure on RxM. The normalized
vorticity and the suspended velocity fields are Hamiltonian with the function t
and the Bernoulli function, respectively. The symplectic structure incorporates
the helicity conservation law as an identity. The infinitesimal dilation for
the symplectic two-form can be interpreted as a current vector for the
helicity. The symplectic dilation implies the existence of contact
hypersurfaces. In particular, these include contact structures on the space of
streamlines and the Bernoulli surfaces. The symplectic structure on RxM can be
realized as symplectisations of these through the Euler equation.


title:
Estimation of Wiener--Ito integrals and polynomials of independent
  Gaussian random variables

abstract:
  In this paper I prove good estimates on the moments and tail distribution of
$k$-fold Wiener--It\^o integrals and also present their natural counterpart for
polynomials of independent Gaussian random variables. The proof is based on the
so-called diagram formula for Wiener--It\^o integrals which yields a good
representation for their products as a sum of such integrals. I intend to show
in a subsequent paper that this method also yields good estimates for
degenerate $U$-statistics. The main result of this paper is a generalization of
the estimates of Hanson and Wright about bilinear forms of independent standard
normal random variables. On the other hand, it is a weaker estimate than the
main result of a paper of Lata{\l}a [6]. But that paper contains an error, and
it is not clear whether its result is true. This question is also discussed
here.


title: Tight Bounds on the Capacity of Binary Input random CDMA Systems

abstract:
  We consider multiple access communication on a binary input additive white
Gaussian noise channel using randomly spread code division. For a general class
of symmetric distributions for spreading coefficients, in the limit of a large
number of users, we prove an upper bound on the capacity, which matches a
formula that Tanaka obtained by using the replica method. We also show
concentration of various relevant quantities including mutual information,
capacity and free energy. The mathematical methods are quite general and allow
us to discuss extensions to other multiuser scenarios.


title: Acyclic edge coloring

abstract: This paper has been withdrawn by the author due to an error in the proof.


title: Search for primes of the form $m^2+1$

abstract:
  The results of the computer hunt for the primes of the form $q = m^2+1$ up to
$10^{20}$ are reported. The number of sign changes of the difference $\pi_q(x)
- \frac{C_q}{2}\int_2^x{du \over \sqrt{u}\log(u)}$ and the error term for this
difference is investigated. The analogs of the Brun's constant and the Skewes
number are calculated. An analog of the B conjecture of Hardy--Littlewood is
formulated. It is argued that there is no Chebyshev bias for primes of the form
$q=m^2+1$. All encountered integrals we were able to express by the logarithmic
integral.


title: Hybrid Reasoning and the Future of Iconic Representations

abstract:
  We give a brief overview of the main characteristics of diagrammatic
reasoning, analyze a case of human reasoning in a mastermind game, and explain
why hybrid representation systems (HRS) are particularly attractive and
promising for Artificial General Intelligence and Computer Science in general.


title: Remarks on bell-shaped lumps: stability and fermionic modes

abstract:
  We consider non-topological, "bell-shaped" localized and regular solutions
available in some 1+1 dimensional scalar field theories. Several properties of
such solutions are studied, namely their stability and the occurence of fermion
bound states in the background of a kink and a kink-anti-kink solutions of the
sine-Gordon model.


title: Applying weighted network measures to microarray distance matrices

abstract:
  In recent work we presented a new approach to the analysis of weighted
networks, by providing a straightforward generalization of any network measure
defined on unweighted networks. This approach is based on the translation of a
weighted network into an ensemble of edges, and is particularly suited to the
analysis of fully connected weighted networks. Here we apply our method to
several such networks including distance matrices, and show that the clustering
coefficient, constructed by using the ensemble approach, provides meaningful
insights into the systems studied. In the particular case of two data sets from
microarray experiments the clustering coefficient identifies a number of
biologically significant genes, outperforming existing identification
approaches.


title:
Scaled solar tracks and isochrones in a large region of the Z-Y plane I.
  From the ZAMS to the TP-AGB end for 0.15 - 2.5 Mo stars

abstract:
  Tracks and isochrones have been computed in the range of initial masses 0.15
- 20 Mo for a grid of 39 chemical compositions with the metal content Z between
0.0001 and 0.070, and helium content Y between 0.23 and 0.46. The Padova
stellar evolution code has been implemented with updated physics. New synthetic
TP-AGB models allow the extension of stellar models and isochrones until the
end of the thermal pulses along the AGB. Software tools for the bidimensional
interpolation (in Y and Z) of the tracks have been tuned. This first paper
presents tracks for low mass stars (from 0.15 to 2.5 Mo) with scaled-solar
abundances and the corresponding isochrones from very old ages down to about 1
Gyr. Tracks and isochrones are made available in tabular form for the adopted
grid of chemical compositions in the plane Z-Y. An interactive web interface
will allow users to obtain isochrones of whatever chemical composition and also
simulated stellar populations with different Y(Z) helium-to-metal enrichment
laws.


title:
A singular perturbation approach to the steady-state 1D
  Poisson-Nernst-Planck modeling

abstract:
  The reduced 1D Poisson-Nernst-Planck (PNP) model of artificial nanopores in
the presence of a permanent charge on the channel wall is studied. More
specifically, we consider the limit where the channel length exceed much the
Debye screening length and channel's charge is sufficiently small. Ion
transport is described by the nonequillibrium steady-state solution of the PNP
system within a singular perturbation treatment. The quantities, 1/lambda --
the ratio of the Debye length to a characteristic length scale and epsilon --
the scaled intrinsic charge density, serve as the singular and the regular
perturbation parameters, respectively. The role of the boundary conditions is
discussed. A comparison between numerics and the analytical results of the
singular perturbation theory is presented.


title:
Regularity, asymptotic behavior and partial uniqueness for
  Smoluchowski's coagulation equation

abstract:
  We consider Smoluchowski's equation with a homogeneous kernel of the form
$a(x,y) = x^\alpha y ^\beta + x^\beta y^\alpha$ with $-1 < \alpha \leq \beta <
1$ and $\lambda := \alpha + \beta \in (-1,1)$. We first show that self-similar
solutions of this equation are infinitely differentiable and prove sharp
results on the behavior of self-similar profiles at $y = 0$ in the case $\alpha
< 0$. We also give some partial uniqueness results for self-similar profiles:
in the case $\alpha = 0$ we prove that two profiles with the same mass and
moment of order $\lambda$ are necessarily equal, while in the case $\alpha < 0$
we prove that two profiles with the same moments of order $\alpha$ and $\beta$,
and which are asymptotic at $y=0$, are equal. Our methods include a new
representation of the coagulation operator, and estimates of its regularity
using derivatives of fractional order.


title: Preparation of Entangled States by Quantum Markov Processes

abstract:
  We investigate the possibility of using a dissipative process to prepare a
quantum system in a desired state. We derive for any multipartite pure state a
dissipative process for which this state is the unique stationary state and
solve the corresponding master equation analytically. For certain states, like
the Cluster states, we use this process to show that the jump operators can be
chosen quasi-locally, i.e. they act non-trivially only on a few, neighboring
qubits. Furthermore, the relaxation time of this dissipative process is
independent of the number of subsystems. We demonstrate the general formalism
by considering arbitrary MPS-PEPS states. In particular, we show that the
ground state of the AKLT-model can be prepared employing a quasi--local
dissipative process.


title:
An off-board quantum point contact as a sensitive detector of cantilever
  motion

abstract:
  Recent advances in the fabrication of microelectromechanical systems (MEMS)
and their evolution into nanoelectromechanical systems (NEMS) have allowed
researchers to measure extremely small forces, masses, and displacements. In
particular, researchers have developed position transducers with resolution
approaching the uncertainty limit set by quantum mechanics. The achievement of
such resolution has implications not only for the detection of quantum behavior
in mechanical systems, but also for a variety of other precision experiments
including the bounding of deviations from Newtonian gravity at short distances
and the measurement of single spins. Here we demonstrate the use of a quantum
point contact (QPC) as a sensitive displacement detector capable of sensing the
low-temperature thermal motion of a nearby micromechanical cantilever.
Advantages of this approach include versatility due to its off-board design,
compatibility with nanoscale oscillators, and, with further development, the
potential to achieve quantum limited displacement detection.


title:
The Two-Loop Six-Gluon MHV Amplitude in Maximally Supersymmetric
  Yang-Mills Theory

abstract:
  We give a representation of the parity-even part of the planar two-loop
six-gluon MHV amplitude of N=4 super-Yang-Mills theory, in terms of
loop-momentum integrals with simple dual conformal properties. We evaluate the
integrals numerically in order to test directly the ABDK/BDS all-loop ansatz
for planar MHV amplitudes. We find that the ansatz requires an additive
remainder function, in accord with previous indications from strong-coupling
and Regge limits. The planar six-gluon amplitude can also be compared with the
hexagonal Wilson loop computed by Drummond, Henn, Korchemsky and Sokatchev in
arXiv:0803.1466 [hep-th]. After accounting for differing singularities and
other constants independent of the kinematics, we find that the Wilson loop and
MHV-amplitude remainders are identical, to within our numerical precision. This
result provides non-trivial confirmation of a proposed n-point equivalence
between Wilson loops and planar MHV amplitudes, and suggests that an additional
mechanism besides dual conformal symmetry fixes their form at six points and
beyond.


title: Hexagon Wilson loop = six-gluon MHV amplitude

abstract:
  We compare the two-loop corrections to the finite part of the light-like
hexagon Wilson loop with the recent numerical results for the finite part of
the MHV six-gluon amplitude in N=4 SYM theory by Bern, Dixon, Kosower, Roiban,
Spradlin, Vergu and Volovich (arXiv:0803.1465 [hep-th]) and demonstrate that
they coincide within the error bars and, at the same time, they differ from the
BDS ansatz by a non-trivial function of (dual) conformal kinematical
invariants. This provides strong evidence that the Wilson loop/scattering
amplitude duality holds in planar N=4 SYM theory to all loops for an arbitrary
number of external particles.


title: Conformal collider physics: Energy and charge correlations

abstract:
  We study observables in a conformal field theory which are very closely
related to the ones used to describe hadronic events at colliders. We focus on
the correlation functions of the energies deposited on calorimeters placed at a
large distance from the collision. We consider initial states produced by an
operator insertion and we study some general properties of the energy
correlation functions for conformal field theories. We argue that the small
angle singularities of energy correlation functions are controlled by the twist
of non-local light-ray operators with a definite spin. We relate the charge two
point function to a particular moment of the parton distribution functions
appearing in deep inelastic scattering. The one point energy correlation
functions are characterized by a few numbers. For ${\cal N}=1$ superconformal
theories the one point function for states created by the R-current or the
stress tensor are determined by the two parameters $a$ and $c$ characterizing
the conformal anomaly. Demanding that the measured energies are positive we get
bounds on $a/c$. We also give a prescription for computing the energy and
charge correlation functions in theories that have a gravity dual. The
prescription amounts to probing the falling string state as it crosses the
$AdS$ horizon with gravitational shock waves. In the leading, two derivative,
gravity approximation the energy is uniformly distributed on the sphere at
infinity, with no fluctuations. We compute the stringy corrections and we show
that they lead to small, non-gaussian, fluctuations in the energy distribution.
Corrections to the one point functions or antenna patterns are related to
higher derivative corrections in the bulk.


title: A sharpened nuclearity condition for massless fields

abstract:
  A recently proposed phase space condition which comprises information about
the vacuum structure and timelike asymptotic behavior of physical states is
verified in massless free field theory. There follow interesting conclusions
about the momentum transfer of local operators in this model.


title: Optical Vortices during a Super-Resolution Process in a Metamaterial

abstract:
  We show that a super-resolution process with 100% visibility is characterized
by the formation of a point of phase singularity in free space outside the lens
in the form of a saddle with topological charge equal to -1. The saddle point
is connected to two vortices at the end boundary of the lens, and the two
vortices are in turn connected to another saddle point inside the lens. The
structure saddle-vortices-saddle is topologically stable. The formation of the
saddle point in free space explains also the negative flux of energy present in
a certain region of space outside the lens. The circulation strength of the
power flow can be controlled by varying the position of the object plane with
respect to the lens.


title: Gluon energy loss in the gauge-string duality

abstract:
  We estimate the stopping length of an energetic gluon in a thermal plasma of
strongly coupled N=4 super-Yang-Mills theory by representing the gluon as a
doubled string rising up out of the horizon.


title: Fluctuations in Mass-Action Equilibrium of Protein Binding Networks

abstract:
  We consider two types of fluctuations in the mass-action equilibrium in
protein binding networks. The first type is driven by relatively slow changes
in total concentrations (copy numbers) of interacting proteins. The second
type, to which we refer to as spontaneous, is caused by quickly decaying
thermodynamic deviations away from the equilibrium of the system. As such they
are amenable to methods of equilibrium statistical mechanics used in our study.
We investigate the effects of network connectivity on these fluctuations and
compare them to their upper and lower bounds. The collective effects are shown
to sometimes lead to large power-law distributed amplification of spontaneous
fluctuations as compared to the expectation for isolated dimers. As a
consequence of this, the strength of both types of fluctuations is positively
correlated with the overall network connectivity of proteins forming the
complex. On the other hand, the relative amplitude of fluctuations is
negatively correlated with the abundance of the complex. Our general findings
are illustrated using a real network of protein-protein interactions in baker's
yeast with experimentally determined protein concentrations.


title:
Three-dimensional structure of the laser wakefield accelerator in the
  blowout regime

abstract:
  Three-dimensional Particle-in-Cell (PIC) simulations with the code QuickPIC
are used to illustrate the typical accelerating structures associated with the
interaction of an intense laser beam with an underdense plasma in the blowout
regime. Our simulations are performed with an externally injected electron
beam, positioned in the region of maximum accelerating gradients. As the laser
propagates in the plasma, almost complete electron cavitation occurs, leading
to the generation of accelerating fields in excess of 1 GeV/cm.


title:
Effect of detector dead-times on the security evaluation of
  differential-phase-shift quantum key distribution against sequential attacks

abstract:
  We investigate limitations imposed by detector dead-times on the performance
of sequential attacks against a differential-phase-shift (DPS) quantum key
distribution (QKD) protocol with weak coherent pulses. In particular, we
analyze sequential attacks based on unambiguous state discrimination of the
signal states emitted by the source and we obtain ultimate upper bounds on the
maximal distance achievable by a DPS QKD scheme both in the so-called trusted
and untrusted device scenarios, respectively.


title:
Optimization of periodic composite structures for sub-wavelength
  focusing

abstract:
  Recently, there has been plenty of work in designing and fabricating
materials with an effective negative refractive index. Veselago realized that a
slab of material with a refractive index of -1 would act as a lens. Pendry
suggested that the Veselago lens would act as a superlens, providing a perfect
image of an object in contrast to conventional lenses which are only able to
focus a point source to an image having a diameter of the order of the
wavelength of the incident field.
  Recent work has shown that similar focusing effects can be obtained with
certain slabs of ``conventional'' periodic composite materials: photonic
crystals. The present work seeks to answer the question of what periodic
dielectric composite medium (described by dielectric coefficient with positive
real part) gives an optimal image of a point source. An optimization problem is
formulated and it is shown that a solution exists provided the medium has small
absorption. Solutions are characterized by an adjoint-state gradient condition,
and several numerical examples illustrate both the plausibility of this design
approach, and the possibility of obtaining smaller image spot sizes than with
typical photonic crystals.


title:
The supergravity dual of 3d supersymmetric gauge theories with
  unquenched flavors

abstract:
  We obtain the supergravity dual of N=1 supersymmetric gauge theory in 2+1
dimensions with a large number of unquenched massless flavors. The geometries
found are obtained by solving the equations of motion of supergravity coupled
to a suitable continuous distribution of flavor branes. The background obtained
preserves two supersymmetries. We find that when N_c\ge 2N_f the behavior of
the solutions is compatible with having an asymptotically free dual gauge
theory with dynamical quarks. On the contrary, when N_c<2N_f the theory
develops a Landau pole in the UV. We also find a new family of (unflavored)
backgrounds generated by D5-branes that wrap a three-cycle of a cone with G_2
holonomy.


title: The Future of Ultracool Dwarf Science with JWST

abstract:
  Ultracool dwarfs exhibit a remarkably varied set of characteristics which
hint at the complex physical processes acting in their atmospheres and
interiors. Spectra of these objects not only depend upon their mass and
effective temperature, but also their atmospheric chemistry, weather, and
dynamics. As a consequence divining their mass, metallicity and age solely from
their spectra has been a challenge. JWST, by illuminating spectral blind spots
and observing objects with constrained masses and ages should finally unearth a
sufficient number of ultracool dwarf Rosetta Stones to allow us to decipher the
processes underlying the complex brown dwarf cooling sequence. In addition the
spectra of objects invisible from the ground, including very low mass objects
in clusters and nearby cold dwarfs from the disk population, will be seen for
the first time. In combination with other ground- and space-based assets and
programs, JWST will usher in a new golden era of brown dwarf science and
discovery.


title:
Some variants of the exponential formula, with application to the
  multivariate Tutte polynomial (alias Potts model)

abstract:
  We prove some variants of the exponential formula and apply them to the
multivariate Tutte polynomials (also known as Potts-model partition functions)
of graphs. We also prove some further identities for the multivariate Tutte
polynomial, which generalize an identity for counting connected graphs found by
Riordan, Nijenhuis, Wilf and Kreweras and in more general form by Leroux and
Gessel, and an identity for the inversion enumerator of trees found by Mallows,
Riordan and Kreweras. Finally, we prove a generalization of Mobius inversion on
the partition lattice.


title:
Measurement-based quantum computer in the gapped ground state of a
  two-body Hamiltonian

abstract:
  We propose a scheme for a ground-code measurement-based quantum computer,
which enjoys two major advantages. First, every logical qubit is encoded in the
gapped degenerate ground subspace of a spin-1 chain with nearest-neighbor
two-body interactions, so that it equips built-in robustness against noise.
Second, computation is processed by single-spin measurements along multiple
chains dynamically coupled on demand, so as to keep teleporting only logical
information into a gap-protected ground state of the residual chains after the
interactions with spins to be measured are turned off. We describe
implementations using trapped atoms or polar molecules in an optical lattice,
where the gap is expected to be as large as 0.2 kHz or 4.8 kHz respectively.


title:
Adiabatic cavity QED with pairs of atoms: Atomic entanglement and
  Quantum teleportation

abstract:
  We study the dynamics of a pair of atoms, resonantly interacting with a
single mode cavity, in the situation where the atoms enter the cavity with a
time delay between them. Using time dependent coupling functions to represent
the spatial profile of the mode, we considered the adiabatic limit of the
system. Although the time evolution is mostly adiabatic, energy crossings play
an important role in the system dynamics. Following from this, entanglement,
and a procedure for cavity state teleportation are considered. We examine the
behaviour of the system when we introduce decoherence, a finite detuning, and
potential asymmetries in the coupling profiles of the atoms.


title:
Lyapunov exponents for the one-dimensional parabolic Anderson model with
  drift

abstract:
  We consider the solution $u$ to the one-dimensional parabolic Anderson model
with homogeneous initial condition $u(0, \cdot) \equiv 1$, arbitrary drift and
a time-independent potential bounded from above. Under ergodicity and
independence conditions we derive representations for both the quenched
Lyapunov exponent and, more importantly, the $p$-th annealed Lyapunov exponents
for {\it all} $p \in (0, \infty).$ These results enable us to prove the
heuristically plausible fact that the $p$-th annealed Lyapunov exponent
converges to the quenched Lyapunov exponent as $p \downarrow 0.$ Furthermore,
we show that $u$ is $p$-intermittent for $p$ large enough. As a byproduct, we
compute the optimal quenched speed of the random walk appearing in the
Feynman-Kac representation of $u$ under the corresponding Gibbs measure. In
this context, depending on the negativity of the potential, a phase transition
from zero speed to positive speed appears.


title:
Energy and Angular Momentum Densities in a Godel-Type Universe in the
  Teleparallel Geometry

abstract:
  The main scope of this research consists in evaluating the energy-momentum
(gravitational field plus matter) and gravitational angular momentum densities
in the universe with global rotation, considering the Godel-Obukhov metric. For
this, we use the Hamiltonian formalism of the Teleparallel Equivalent of
General Relativity (TEGR), which is justified for presenting covariant
expressions for the considered quantities. We found that the total energy
density calculated by the TEGR method is in agreement with the results reported
by other authors in the literature using pseudotensors. The result found for
the angular momentum density depends on the rotational parameter as expected.
We also show explicitly the equivalence among the field equations of the TEGR
and Einstein equations (RG), considering a perfect fluid and Godel-Obukhov
metric.


title: Quantum States and Phases in Driven Open Quantum Systems with Cold Atoms

abstract:
  An open quantum system, whose time evolution is governed by a master
equation, can be driven into a given pure quantum state by an appropriate
design of the system-reservoir coupling. This points out a route towards
preparing many body states and non-equilibrium quantum phases by quantum
reservoir engineering. Here we discuss in detail the example of a \emph{driven
dissipative Bose Einstein Condensate} of bosons and of paired fermions, where
atoms in an optical lattice are coupled to a bath of Bogoliubov excitations via
the atomic current representing \emph{local dissipation}. In the absence of
interactions the lattice gas is driven into a pure state with long range order.
Weak interactions lead to a weakly mixed state, which in 3D can be understood
as a depletion of the condensate, and in 1D and 2D exhibits properties
reminiscent of a Luttinger liquid or a Kosterlitz-Thouless critical phase at
finite temperature, with the role of the ``finite temperature'' played by the
interactions.


title:
Measuring Ages and Elemental Abundances from Unresolved Stellar
  Populations: Fe, Mg, C, N, and Ca

abstract:
  We present a method for determining mean light-weighted ages and abundances
of Fe, Mg, C, N, and Ca, from medium resolution spectroscopy of unresolved
stellar populations. The method, pioneered by Schiavon (2007), is implemented
in a publicly available code called EZ_Ages. The method and error estimation
are described, and the results tested for accuracy and consistency, by
application to integrated spectra of well-known Galactic globular and open
clusters. Ages and abundances from integrated light analysis agree with studies
of resolved stars to within +/-0.1 dex for most clusters, and to within +/-0.2
dex for nearly all cases. The results are robust to the choice of Lick indices
used in the fitting to within +/-0.1 dex, except for a few systematic
deviations which are clearly categorized. The realism of our error estimates is
checked through comparison with detailed Monte Carlo simulations. Finally, we
apply EZ_Ages to the sample of galaxies presented in Thomas et al. (2005) and
compare our derived values of age, [Fe/H], and [alpha/Fe] to their analysis. We
find that [alpha/Fe] is very consistent between the two analyses, that ages are
consistent for old (Age > 10 Gyr) populations, but show modest systematic
differences at younger ages, and that [Fe/H] is fairly consistent, with small
systematic differences related to the age systematics. Overall, EZ_Ages
provides accurate estimates of fundamental parameters from medium resolution
spectra of unresolved stellar populations in the old and intermediate-age
regime, for the first time allowing quantitative estimates of the abundances of
C, N, and Ca in these unresolved systems. The EZ_Ages code can be downloaded at
http://www.ucolick.org/~graves/EZ_Ages.html


title:
Strong Near-Infrared Emission Interior to the Dust-Sublimation Radius of
  Young Stellar Objects MWC275 and AB Aur

abstract:
  Using the longest optical-interferometeric baselines currently available, we
have detected strong near-infrared (NIR) emission from inside the
dust-destruction radius of Herbig Ae stars MWC275 and AB Aur. Our
sub-milli-arcsecond resolution observations unambiguously place the emission
between the dust-destruction radius and the magnetospheric co-rotation radius.
We argue that this new component corresponds to hot gas inside the
dust-sublimation radius, confirming recent claims based on spectrally-resolved
interferometry and dust evaporation front modeling.


title: Dirichlet boundary value problem for Chern-Simons modified gravity

abstract:
  Chern-Simons modified gravity comprises the Einstein-Hilbert action and a
higher-derivative interaction containing the Chern-Pontryagin density. We
derive the analog of the Gibbons-Hawking-York boundary term required to render
the Dirichlet boundary value problem well-defined. It turns out to be a
boundary Chern-Simons action for the extrinsic curvature. We address
applications to black hole thermodynamics.


title: Robust d-wave Pairing Correlations in the Heisenberg Kondo Lattice Model

abstract:
  The Kondo lattice model enlarged by an antiferromagnetic coupling $J_{\rm
AF}$ between the localized spins is here investigated using computational
techniques. Our results suggest the existence of a d-wave superconducting phase
close to half-filling mediated by antiferromagnetic fluctuations. This
establishes a closer connection between theory and heavy fermion experiments
than currently provided by the standard Kondo lattice model with $J_{\rm
AF}$=0.


title: The Youngest Galactic Supernova Remnant: G1.9+0.3

abstract:
  Our 50 ks Chandra observation of the small radio supernova remnant (SNR)
G1.9+0.3 shows a complete shell structure with strong bilateral symmetry, about
$100''$ in diameter. The radio morphology is also shell-like, but only about
$84''$ in diameter, based on observations made in 1985. We attribute the size
difference to expansion between 1985 and our Chandra observations of 2007.
Expansion is confirmed in comparing radio images from 1985 and 2008. We deduce
that G1.9+0.3 is of order 100 years old -- the youngest supernova remnant in
the Galaxy. Based on a very high absorbing column density of $5.5 \times
10^{22}$ cm$^{-2}$, we place G1.9+0.3 near the Galactic Center, at a distance
of about 8.5 kpc, where the mean remnant radius would be about 2 pc, and the
required expansion speed about $14,000$ km s$^{-1}$. The X-ray spectrum is
featureless and well-described by the exponentially cut off synchrotron model
{\tt srcut}. With the radio flux at 1 GHz fixed at 0.9 Jy, we find a spectral
index of 0.65 and a rolloff frequency of $1.4 \times 10^{18}$ Hz. The implied
characteristic rolloff electron energy of about $94 (B/10 \mu{\rm G})^{-1/2}$
TeV is the highest ever reported for a shell supernova remnant. It can easily
be reached by standard diffusive shock acceleration, given the very high shock
velocities; it can be well described by either age-limited or
synchrotron-loss-limited acceleration. Not only is G1.9+0.3 the youngest known
Galactic remnant, it is also only the fourth Galactic X-ray
synchrotron-dominated shell supernova remnant.


title:
Deep MMT Transit Survey of the Open Cluster M37 III: Stellar Rotation at
  550 Myr

abstract:
  In the course of conducting a deep (14.5 ~< r ~< 23), 20 night survey for
transiting planets in the rich ~550 Myr old open cluster M37 we have measured
the rotation periods of 575 stars which lie near the cluster main sequence,
with masses 0.2 Msun ~< M ~< 1.3 Msun. This is the largest sample of rotation
periods for a cluster older than 500 Myr. Using this rich sample we investigate
a number of relations between rotation period, color and the amplitude of
photometric variability. Stars with M >~ 0.8 Msun show a tight correlation
between period and mass with heavier stars rotating more rapidly. There is a
group of 4 stars with P > 15 days that fall well above this relation, which, if
real, would present a significant challenge to theories of stellar angular
momentum evolution. Below 0.8 Msun the stars continue to follow the period-mass
correlation but with a broad tail of rapid rotators that expands to shorter
periods with decreasing mass. We combine these results with observations of
other open clusters to test the standard theory of lower-main sequence stellar
angular momentum evolution. We find that the model reproduces the observations
for solar mass stars, but discrepancies are apparent for stars with 0.6 ~< M ~<
1.0 Msun. We also find that for late-K through early-M dwarf stars in this
cluster rapid rotators tend to be bluer than slow rotators in B-V but redder
than slow rotators in V-I_{C}. This result supports the hypothesis that the
significant discrepancy between the observed and predicted temperatures and
radii of low-mass main sequence stars is due to stellar activity.


title:
The contribution of star formation and merging to stellar mass buildup
  in galaxies

abstract:
  We present a formalism to infer the presence of merging by comparing the time
derivative of the observed galaxy stellar mass function (MF) to the change of
the MF expected from the star formation rate (SFR) in galaxies as a function of
mass and time. We present the SFR in as a function of stellar mass and time
spanning 9<logM<12 and 0<z<5. We show that at z>=3 the average SFR, is a power
law of stellar mass (SFR~M^0.6). The average SFR in the most massive objects at
this redshift is 100-500 Msun/yr. At z~3, the SFR starts to drop at the high
mass end. As z decreases further, the SFR drops at progressively lower masses
(downsizing), dropping most rapidly for high mass (logM>11) galaxies. The mass
at which the SFR starts to deviate from the power-law form (break mass)
progresses smoothly from logM~13 at z~5 to logM~10.9 at z~0.5. The break mass
evolves with redshift as M(z)=2.7x10^10 (1+z)^2.1. We directly observe a
relationship between SFH and mass. More massive galaxies have steeper and
earlier onsets of SF, their SFR peaks earlier and higher, and the following
decay has a shorter e-folding time. The SFR observed in high mass galaxies at
z~4 is sufficient to explain their rapid increase in number density. Within
large uncertainties, at most 0.8 major mergers per Gyr are consistent with the
high-z data, yet enough to transform most high mass objects into ellipticals
contemporaneously with their major star formation episode. In contrast, at
z<1.5 and at logM>11, mergers contribute 0.1-0.2 Gyr^-1 to the relative
increase in number density (~1 major merger per massive object at 1.5>z>0). At
10<logM<11, galaxies are being preferably destroyed in mergers at high z, while
at later times the change in their numbers turns positive. This shows the
top-down buildup of the red sequence suggested by other observations.


title: Cosmic Shear from Scalar-Induced Gravitational Waves

abstract:
  Weak gravitational lensing by foreground density perturbations generates a
gradient mode in the shear of background images. In contrast, cosmological
tensor perturbations induce a non-zero curl mode associated with image
rotations. In this note, we study the lensing signatures of both primordial
gravitational waves from inflation and second-order gravitational waves
generated from the observed spectrum of primordial density fluctuations. We
derive the curl mode for galaxy lensing surveys at redshifts of 1 to 3 and for
lensing of the cosmic microwave background (CMB) at a redshift of 1100. We find
that the curl mode angular power spectrum associated with secondary tensor
modes for galaxy lensing surveys dominates over the corresponding signal
generated by primary gravitational waves from inflation. However, both tensor
contributions to the shear curl mode spectrum are below the projected noise
levels of upcoming galaxy and CMB lensing surveys and therefore are unlikely to
be detectable.


title:
The Effects of Halo Assembly Bias on Self-Calibration in Galaxy Cluster
  Surveys

abstract:
  Self-calibration techniques for analyzing galaxy cluster counts utilize the
abundance and the clustering amplitude of dark matter halos. These properties
simultaneously constrain cosmological parameters and the cluster
observable-mass relation. It was recently discovered that the clustering
amplitude of halos depends not only on the halo mass, but also on various
secondary variables, such as the halo formation time and the concentration;
these dependences are collectively termed assembly bias. Applying modified
Fisher matrix formalism, we explore whether these secondary variables have a
significant impact on the study of dark energy properties using the
self-calibration technique in current (SDSS) and the near future (DES, SPT, and
LSST) cluster surveys. The impact of the secondary dependence is determined by
(1) the scatter in the observable-mass relation and (2) the correlation between
observable and secondary variables. We find that for optical surveys, the
secondary dependence does not significantly influence an SDSS-like survey;
however, it may affect a DES-like survey (given the high scatter currently
expected from optical clusters) and an LSST-like survey (even for low scatter
values and low correlations). For an SZ survey such as SPT, the impact of
secondary dependence is insignificant if the scatter is 20% or lower but can be
enhanced by the potential high scatter values introduced by a highly correlated
background. Accurate modeling of the assembly bias is necessary for cluster
self-calibration in the era of precision cosmology.


title:
Reversibility of Interacting Fleming-Viot Processes with Mutation,
  Selection, and Recombination

abstract:
  Reversibility of the Fleming-Viot process with mutation, selection, and
recombination is well understood. In this paper, we study the reversibility of
a system of Fleming-Viot processes that live on a countable number of colonies
interacting with each other through migrations between the colonies. It is
shown that reversibility fails when both migration and mutation are
non-trivial.


title:
Na atomic order, Co charge disproportionation and magnetism in
  Na$_{x}$CoO$_{2}$ for large Na contents

abstract:
  We have synthesized and characterized four different stable phases of Na
ordered Na$_{x}$CoO$_{2}$, for $0.65<x<0.8$. Above 100 K they display similar
Curie-Weiss susceptibilities as well as ferromagnetic $q=0$ spin fluctuations
in the CoO$_{2}$ planes revealed by $^{23}$Na NMR data. In all phases from
$^{59}$Co NMR data we display evidences that the Co disproportionate already
above 300 K into non magnetic Co$^{3+}$ and magnetic $\approx $Co$^{3.5+}$
sites on which holes delocalize. This allows us to understand that metallic
magnetism is favored for these large Na contents. Below 100 K the phases
differentiate, and a magnetic order sets in only for $x\gtrsim 0.75$ at
$T_{N}=$22 K. We suggest that the charge order also governs the low $T$ energy
scales and transverse couplings.


title: The quintic interaction vertex in light-cone gravity

abstract:
  We consider pure gravity in light-cone gauge and derive the complete quintic
interaction vertex. Up to quartic order, the Kawai-Lewellen-Tye (KLT) relations
can be made manifest at the level of the Einstein-Hilbert Lagrangian. The
quintic interaction vertex represents an essential first step in further
extending the off-shell validity of the KLT relations to higher order vertices.


title: Encoding One Logical Qubit Into Six Physical Qubits

abstract:
  We discuss two methods to encode one qubit into six physical qubits. Each of
our two examples corrects an arbitrary single-qubit error. Our first example is
a degenerate six-qubit quantum error-correcting code. We explicitly provide the
stabilizer generators, encoding circuit, codewords, logical Pauli operators,
and logical CNOT operator for this code. We also show how to convert this code
into a non-trivial subsystem code that saturates the subsystem Singleton bound.
We then prove that a six-qubit code without entanglement assistance cannot
simultaneously possess a Calderbank-Shor-Steane (CSS) stabilizer and correct an
arbitrary single-qubit error. A corollary of this result is that the Steane
seven-qubit code is the smallest single-error correcting CSS code. Our second
example is the construction of a non-degenerate six-qubit CSS
entanglement-assisted code. This code uses one bit of entanglement (an ebit)
shared between the sender and the receiver and corrects an arbitrary
single-qubit error. The code we obtain is globally equivalent to the Steane
seven-qubit code and thus corrects an arbitrary error on the receiver's half of
the ebit as well. We prove that this code is the smallest code with a CSS
structure that uses only one ebit and corrects an arbitrary single-qubit error
on the sender's side. We discuss the advantages and disadvantages for each of
the two codes.


title: The similarity problem for $J$-nonnegative Sturm-Liouville operators

abstract:
  Sufficient conditions for the similarity of the operator $A := 1/r(x)
(-d^2/dx^2 +q(x))$ with an indefinite weight $r(x)=(\sgn x)|r(x)|$ are
obtained. These conditions are formulated in terms of Titchmarsh-Weyl
$m$-coefficients. Sufficient conditions for the regularity of the critical
points 0 and $\infty$ of $J$-nonnegative Sturm-Liouville operators are also
obtained. This result is exploited to prove the regularity of 0 for various
classes of Sturm-Liouville operators. This implies the similarity of the
considered operators to self-adjoint ones. In particular, in the case
$r(x)=\sgn x$ and $q\in L^1(R, (1+|x|)dx)$, we prove that $A$ is similar to a
self-adjoint operator if and only if $A$ is $J$-nonnegative. The latter
condition on $q$ is sharp, i.e., we construct $q\in \cap_{\gamma <1} L^1(R,
(1+|x|)^\gamma dx)$ such that $A$ is $J$-nonnegative with the singular critical
point 0. Hence $A$ is not similar to a self-adjoint operator. For periodic and
infinite-zone potentials, we show that $J$-positivity is sufficient for the
similarity of $A$ to a self-adjoint operator. In the case $q\equiv 0$, we prove
the regularity of the critical point 0 for a wide class of weights $r$. This
yields new results for "forward-backward" diffusion equations.


title: Cyclic Approximation to K-Stasis

abstract:
  If a linear combination of k smooth vector fields is zero at a point, then,
generically, near this point there are small cycles comprised of segments from
the flow of each vector field. This answers a question posed in
arXiv:math/0504365.


title:
Evolution from BCS to BKT superfluidity in one-dimensional optical
  lattices

abstract:
  We analyze the finite temperature phase diagram of fermion mixtures in
one-dimensional optical lattices as a function of interaction strength. At low
temperatures, the system evolves from an anisotropic three-dimensional
Bardeen-Cooper-Schrieffer (BCS) superfluid to an effectively two-dimensional
Berezinskii-Kosterlitz-Thouless (BKT) superfluid as the interaction strength
increases. We calculate the critical temperature as a function of interaction
strength, and identify the region where the dimensional crossover occurs for a
specified optical lattice potential. Finally, we show that the dominant vortex
excitations near the critical temperature evolve from multiplane elliptical
vortex loops in the three-dimensional regime to planar vortex-antivortex pairs
in the two-dimensional regime, and we propose a detection scheme for these
excitations.


title:
Multipartite Entanglement in Non-Equilibrium Quantum Phase Transition in
  a Collective Atomic System

abstract:
  We study multipartite entanglement in non-equilibrium quantum phase
transition (NEQPT) attainable in a coherently driven atomic ensemble undergoing
collective decay. The NEQPT arises in the steady state of the system as the
drive field strength is varied in comparison with the decay parameter. A close
connection is observed between the critical behavior and the multi-partite
entanglement in the system determined via the von Neumann entropy. The
derivative of the von Neumann entropy shows Lambda-type behavior typical of the
second order phase transitions. We further show that the calculated bi- and
tri- partite entropies satisfy the Lieb inequality.


title:
NCore: Architecture and Implementation of a Flexible, Collaborative
  Digital Library

abstract:
  NCore is an open source architecture and software platform for creating
flexible, collaborative digital libraries. NCore was developed by the National
Science Digital Library (NSDL) project, and it serves as the central technical
infrastructure for NSDL. NCore consists of a central Fedora-based digital
repository, a specific data model, an API, and a set of backend services and
frontend tools that create a new model for collaborative, contributory digital
libraries. This paper describes NCore, presents and analyzes its architecture,
tools and services; and reports on the experience of NSDL in building and
operating a major digital library on it over the past year and the experience
of the Digital Library for Earth Systems Education in porting their existing
digital library and tools to the NCore platform.


title:
Self-consistent crystalline condensate in chiral Gross-Neveu and
  Bogoliubov-de Gennes systems

abstract:
  We derive a new exact self-consistent crystalline condensate in the 1+1
dimensional chiral Gross-Neveu model. This also yields a new exact crystalline
solution for the one dimensional Bogoliubov-de Gennes equations and the
Eilenberger equation of semiclassical superconductivity. We show that the
functional gap equation can be reduced to a solvable nonlinear equation, and
discuss implications for the temperature-chemical potential phase diagram.

categories: hep-th cond-mat.supr-con hep-lat hep-ph quant-ph


title:
Recurrence relations for characters of affine Lie algebra
  $A_{\ell}^{(1)}$

abstract:
  By using the known description of combinatorial bases for
Feigin-Stoyanovsky's type subspaces of standard modules for affine Lie algebra
$\mathfrak{sl}(l+1,\mathbb{C})^{\widetilde{}}$, as well as certain intertwining
operators between standard modules, we obtain exact sequences of
Feigin-Stoyanovsky's type subspaces at fixed level $k$. This directly leads to
systems of recurrence relations for formal characters of those subspaces.


title:
Variational HFB Equations in the Thomas-Fermi Limit for Ultracold
  Trapped Gases

abstract:
  We derive variationally the HFB equations for a trapped self-interacting Bose
gas at finite temperature. In the Thomas-Fermi limit, we obtain simple
expressions for the condensate, the non condensate and the anomalous densities.
Their behavior in terms of the condensate fraction meets qualitatively the
experimental data. In particular, the non condensate and the anomalous
densities are peaked at the center of the trap and not at the edges as
predicted by the self-consistent HFB calculations.


title:
The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. XI. Lupus
  Observed With IRAC and MIPS

abstract:
  We present c2d Spitzer/IRAC observations of the Lupus I, III and IV dark
clouds and discuss them in combination with optical and near-infrared and c2d
MIPS data. With the Spitzer data, the new sample contains 159 stars, 4 times
larger than the previous one. It is dominated by low- and very-low mass stars
and it is complete down to M $\approx$ 0.1M$_\odot$. We find 30-40 % binaries
with separations between 100 to 2000 AU with no apparent effect in the disk
properties of the members. A large majority of the objects are Class II or
Class III objects, with only 20 (12%) of Class I or Flat spectrum sources. The
disk sample is complete down to ``debris''-like systems in stars as small as M
$\approx$ 0.2 M$_\odot$ and includes sub-stellar objects with larger IR
excesses. The disk fraction in Lupus is 70 -- 80%, consistent with an age of 1
-- 2 Myr. However, the young population contains 20% optically thick accretion
disks and 40% relatively less flared disks. A growing variety of inner disk
structures is found for larger inner disk clearings for equal disk masses.
Lupus III is the most centrally populated and rich, followed by Lupus I with a
filamentary structure and by Lupus IV, where a very high density core with
little star-formation activity has been found. We estimate star formation rates
in Lupus of 2 -- 10 M$_\odot$ Myr$^{-1}$ and star formation efficiencies of a
few percent, apparently correlated with the associated cloud masses.


title: Cometary activity at 25.7 AU: Hale--Bopp 11 years after perihelion

abstract:
  Eleven years after its perihelion, comet C/1995 O1 (Hale-Bopp) is still
active. Between October 20--22, 2007, we detected a diffuse coma of 180x10^3$km
in diameter with a slight elongation toward N/S direction. The integrated
brightness was 20.04 mag in R_C, implying Af\rho=300 m and albedo x dust
surface $a_RC$=4300 km^2. The coma was relatively red at V-R=0.66 mag, which is
consistent with that of the dust in other comets. The observed properties and
the overall fading in brightness between 10 AU and 26 AU follow the predicted
behaviour of CO-driven activity (Capria et al. 2002). This is the most distant
cometary activity ever observed.


title: Discrete Affine Minimal Surfaces with Indefinite Metric

abstract:
  Inspired by the Weierstrass representation of smooth affine minimal surfaces
with indefinite metric, we propose a constructive process producing a large
class of discrete surfaces that we call discrete affine minimal surfaces. We
show that they are critical points of an affine area functional defined on the
space of quadrangular discrete surfaces. The construction makes use of
asymptotic coordinates and allows defining the discrete analogs of some
differential geometric objects, such as the normal and co normal vector fields,
the cubic form and the compatibility equations.


title:
The tightening of wide binaries in dSph galaxies through dynamical
  friction as a test of the Dark Matter hypothesis

abstract:
  We estimate the timescales for orbital decay of wide binaries embedded within
dark matter halos, due to dynamical friction against the dark matter particles.
We derive analytical scalings for this decay and calibrate and test them
through the extensive use of N-body simulations, which accurately confirm the
predicted temporal evolution. For density and velocity dispersion parameters as
inferred for the dark matter halos of local dSph galaxies, we show that the
decay timescales become shorter than the ages of the dSph stellar populations
for binary stars composed of 1 $M_{\odot}$ stars, for initial separations
larger than 0.1 pc. Such wide binaries are conspicuous and have been well
measured in the solar neighborhood. The prediction of the dark matter
hypothesis is that they should now be absent from stellar populations embedded
within low velocity dispersion, high density dark mater halos, as currently
inferred for the local dSph galaxies, having since evolved into tighter
binaries. Relevant empirical determinations of this will become technically
feasible in the near future, and could provide evidence to discriminate between
dark matter particle halos or modified gravitational theories, to account for
the high dispersion velocities measured for stars in local dSph galaxies.


title:
A Hidden Symmetry Related to the Riemann Hypothesis with the Primes into
  the Critical Strip

abstract:
  In this note concerning integrals involving the logarithm of the Riemann Zeta
function, we extend some treatments given in previous pioneering works on the
subject and introduce a more general set of Lorentz measures. We first obtain
two new equivalent formulations of the Riemann Hypothesis (RH). Then with a
special choice of the measure we formulate the RH as a ``hidden symmetry'', a
global symmetry which connects the region outside the critical strip with that
inside the critical strip. The Zeta function with all the primes appears as
argument of the Zeta function in the critical strip. We then illustrate the
treatment by a simple numerical experiment. The representation we obtain go a
little more in the direction to believe that RH may eventually be true.


title: New Findings for the Blue Plume Stars in the Canis Major Over-Density

abstract:
  We obtained new UBV photometry and spectroscopy of Blue Plume (BP) stars in
fields near the center of the Canis Major Over-Density (CMa). We combined
analysis of the color-color diagrams with a new comparison of the hydrogen
Balmer-line profile to the reddening-free Q parameter to improve the reddening
and extinction estimates for this low-latitude, differentially reddened, area
of the sky. Results of our stellar parameter analysis for B/A spectral type
stars associated with the BP show that the majority of the stars have
main-sequence surface gravities placing them at an average heliocentric
distance of <D> = 6.0 +/- 2.7 kpc. This distance is more consistent with
membership in the intervening Perseus spiral arm and strongly suggests that the
BP stars are not associated with the other stellar populations previously
reported to make up the CMa. This result casts serious doubt on the proposed
dwarf galaxy origin for the CMa.


title:
A method for investigating relative timing information on phylogenetic
  trees

abstract:
  In this paper we present a new way to understand the timing of branching
events in phylogenetic trees. Our method explicitly considers the relative
timing of diversification events between sister clades; as such it is
complimentary to existing methods using lineages-through-time plots which
consider diversification in aggregate. The method looks for evidence of
diversification happening in lineage-specific ``bursts'', or the opposite,
where diversification between two clades happens in an unusually regular
fashion. In order to be able to distinguish interesting events from
stochasticity, we propose two classes of neutral models on trees with timing
information and develop a statistical framework for testing these models. Our
models substantially generalize both the coalescent with ancestral population
size variation and the global-rate speciation-extinction models. We end the
paper with several example applications: first, we show that the evolution of
the Hepatitis C virus appears to proceed in a lineage-specific bursting
fashion. Second, we analyze a large tree of ants, demonstrating that a period
of elevated diversification rates does not appear to occurred in a bursting
manner.


title: The Capacity Region of the Degraded Finite-State Broadcast Channel

abstract:
  We consider the discrete, time-varying broadcast channel with memory under
the assumption that the channel states belong to a set of finite cardinality.
We first define the physically degraded finite-state broadcast channel for
which we derive the capacity region. We then define the stochastically degraded
finite-state broadcast channel and derive the capacity region for this scenario
as well. In both scenarios we consider the non-indecomposable finite-state
channel as well as the indecomposable one.


title: A Protocol for Quantum Energy Distribution

abstract:
  A new protocol, quantum energy distribution (QED), is proposed in which
multiple parties can simultaneously extract positive energy from spin chains by
common secret keys shared by an energy supplier. QED is robust against
impersonation; an adversary, who does not have a common secret key and attempts
to get energy, will instead give energy to the spin chains. The total amount of
energy transfer gives a lower bound of the residual energy of any local cooling
process by the energy supplier.


title: Proton to pion ratio at RHIC from dynamical quark recombination

abstract:
  We propose an scenario to study, from a dynamical point of view, the thermal
recombination of quarks in the midsts of a relativistic heavy-ion collision. We
coin the term dynamical quark recombination to refer to the process of
quark-antiquark and three-quark clustering, to form mesons and baryons,
respectively, as a function of energy density. Using the string-flip model we
show that the probabilities to form such clusters differ. We apply these ideas
to the calculation of the proton and pion spectra in a Bjorken-like scenario
that incorporates the evolution of these probabilities with proper time and
compute the proton to pion ratio, comparing to recent RHIC data at the highest
energy. We show that for a standard choice of parameters, this ratio reaches
one, though the maximum is very sensitive to the initial evolution proper time.


title:
Search for $h_f\to\gamma\gamma$ with the D0 detector at $\sqrt{s}=1.96$
  TeV

abstract:
  We report the results of a search for a narrow resonance decaying into two
photons in 1.1 fb$^{-1}$ of data collected by the D0 experiment at the Fermilab
Tevatron Collider during the period 2002-2006. We find no evidence for such a
resonance and set a lower limit on the mass of a fermiophobic Higgs boson of
$m_{h_f}>100$ GeV at the 95% C.L. This exclusion limit exceeds those obtained
in previous searches at the Tevatron and covers a significant region of the
parameter space $B(h_{f}\to\gamma\gamma)$ vs. $m_{h_f}$ which was not
accessible at the CERN LEP Collider.