title:
Nuclear magnetic octupole moment and the hyperfine structure of the
  $5D_{3/2,5/2}$ states of the Ba$^+$ ion

abstract:
  The hyperfine structure of the long-lived $5D_{3/2}$ and $5D_{5/2}$ levels of
Ba$^+$ ion is analyzed. A procedure for extracting relatively unexplored
nuclear magnetic moments $\Omega$ is presented. The relevant electronic matrix
elements are computed in the framework of the ab initio relativistic many-body
perturbation theory. Both the first- and the second-order (in the hyperfine
interaction) corrections to the energy levels are analyzed. It is shown that a
simultaneous measurement of the hyperfine structure of the entire $5D_J$
fine-structure manifold allows one to extract $\Omega$ without contamination
from the second-order corrections. Measurements to the required accuracy should
be possible with a single trapped barium ion using sensitive techniques already
demonstrated in Ba$^+$ experiments.


title:
The population of pulsars with interpulses and the implications for beam
  evolution

abstract:
  The observed fraction of pulsars with interpulses, their period distribution
and the observed pulse width versus pulse period correlation is shown to be
inconsistent with a model in which the angle alpha between the magnetic axis
and the rotation axis is random. This conclusion appears to be unavoidable,
even when non-circular beams are considered. Allowing the magnetic axis to
align from a random distribution at birth with a timescale of 70 Myrs years
can, however, explain those observations well. The timescale derived is
consistent with that obtained via independent methods. The probability that a
pulsar beam intersects the line of sight is a function of the angle alpha and
therefore beam evolution has important consequences for evolutionary models and
for estimations of the total number of neutron stars. The validity of the
standard formula for the spin-down rate, which is independent of alpha appears
to be questionable.


title: The "Shoulder" and the "Ridge" in PHENIX

abstract:
  The observation of jet quenching in ultra-relativistic heavy ion collisions
demonstrates significant energy loss of fast partons when passing through the
created medium. Correlations between final-state particles at intermediate
transverse momentum (1.0 $\lesssim$ $p_{T}$ $\lesssim$ 4.0 GeV/$c$) allow for
study of the medium and its response to deposited energy. Comparison of these
measurements in heavy ion collisions with measurements in proton collisions
show strong modification of the correlation shape and particle yields. Two new
structures are created, both extended in $\Delta\eta$, one centered at
$\Delta\phi=0$ (``ridge'') and the other occurring at
$\Delta\phi\approx\pi\pm1.1$ (``shoulder''). In these proceedings, we describe
the measurements of these structures that show consistency with a scenario of
parton-medium interaction and response. We discuss a new analysis which selects
on the angle of trigger particles relative to the reaction plane in Run7. New
measurements of the centrality and $p_{T}$ dependencies of the structures raise
the possibility that the same production mechanism may give rise to both
phenomena.


title: Charmonium dynamics in dA and AA at RHIC and LHC

abstract:
  We discuss features of charmonium suppression at $\sqtr{s} = 200$ GeV within
the framework of the Glauber-Gribov theory and the comovers interaction model.
The latter approach has been extended by allowing for secondary charmonium
production due to recombination of $c\bar{c}$ pairs in the medium, estimated
from pp data at the same bombarding energy. Centrality and rapidity dependence
of the nuclear modification factor for J/psi in d+Au, Cu+Cu and Au+Au
collisions at RHIC are reproduced without fitting a single model parameter. A
strong suppression of J/psi is predicted for LHC energies.


title: Ideal and nonideal electromagnetic cloaks

abstract:
  We employ the analytical results for the spatial transformation of the
electromagnetic fields to obtain and analyze explicit expressions for the
structure of the electromagnetic fields in invisibility cloaks, beam splitters,
and field concentrators. We study the efficiency of nonideal electromagnetic
cloaks and discuss the effect of scattering losses on the cloak invisibility.


title: Large Deviations for Random Spectral Measures and Sum Rules

abstract:
  We prove a Large Deviation Principle for the random spec- tral measure
associated to the pair $(H_N; e)$ where $H_N$ is sampled in the GUE(N) and e is
a fixed unit vector (and more generally in the $\beta$- extension of this
model). The rate function consists of two parts. The contribution of the
absolutely continuous part of the measure is the reversed Kullback information
with respect to the semicircle distribution and the contribution of the
singular part is connected to the rate function of the extreme eigenvalue in
the GUE. This method is also applied to the Laguerre and Jacobi ensembles, but
in thoses cases the expression of the rate function is not so explicit.


title: The Connectivity Order of Links

abstract:
  We associate at each link a connectivity space which describes its
splittability properties. Then, the notion of order for finite connectivity
spaces results in the definition of a new numerical invariant for links, their
connectivity order. A section of this short paper presents a theorem which
asserts that every finite connectivity structure can be realized by a link :
the Brunn-Debrunner-Kanenobu Theorem.


title: Hochschild Homology and Cohomology of Klein Surfaces

abstract:
  Within the framework of deformation quantization, a first step towards the
study of star-products is the calculation of Hochschild cohomology. The aim of
this article is precisely to determine the Hochschild homology and cohomology
in two cases of algebraic varieties. On the one hand, we consider singular
curves of the plane; here we recover, in a different way, a result proved by
Fronsdal and make it more precise. On the other hand, we are interested in
Klein surfaces. The use of a complex suggested by Kontsevich and the help of
Groebner bases allow us to solve the problem.

categories: math-ph cs.SC math.AC math.MP math.QA math.RA


title:
Int\'egration du contr\^ole automatique dans la ma\^itrise statistique
  des proc\'ed\'es

abstract:
  The Statistical Process Control (SPC) and the Automated Process Control (APC)
have a common goal: achieve optimal product quality by controlling variations
in the process. The work in this paper will present a developed integration
methodology of the APC in the SPC which is based on discretization of the
transfer functions relating to each component of the process. We proposed on
the one hand, a new control rule which is based on a system of first order. In
the other hand, we showed how to establish control charts to a process of the
type AR (1). Using simulation experiments, we showed that the proposed control
rule reduced variability by comparing it with that proposed in literature.


title: Thermodynamics of noncommutative de Sitter spacetime

abstract:
  We study the effects of noncommutativity of spacetime geometry on the
thermodynamical properties of the de Sitter horizon. We show that
noncommutativity results in modifications in temperature, entropy and vacuum
energy and that these modifications are of order of the Planck scale,
suggesting that the size of the noncommutative parameter should be close to
that of the Planck. In an alternative way to deal with noncommutativity, we
obtain a quantization rule for the entropy. Since noncommutativity in spacetime
geometry modifies the Heisenberg algebra and introduces the general uncertainty
principle, we also investigate the above problem in this framework.


title: Some remarks on cabling, contact structures, and complex curves

abstract:
  We determine the relationship between the contact structure induced by a
fibered knot, K, in the three-sphere and the contact structures induced by its
various cables. Understanding this relationship allows us to classify fibered
cable knots which bound a properly embedded complex curve in the four-ball
satisfying a genus constraint. This generalizes the well-known classification
of links of plane curve singularities.


title:
Fourier-Laplace transform of a variation of polarized complex Hodge
  structure, II

abstract:
  We show that the limit, by rescaling, of the `new supersymmetric index'
attached to the Fourier-Laplace transform of a polarized variation of Hodge
structure on a punctured affine line is equal to the spectral polynomial
attached to the same object. We also extend the definition by Deligne of a
Hodge filtration on the de Rham cohomology of a exponentially twisted polarized
variation of complex Hodge structure and prove a E_1 degeneration property for
it.


title:
Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in
  the Doped-Mott Region

abstract:
  We study the triangular $t$-$J$ model with multiple spin exchange
interactions using exact diagonalization of small clusters, as a model of
monolayer liquid $^3$He. A phase where the energy spectrum suggest the
behaviors of spin-charge separation is realized in the doped-Mott region due to
the competition between ferromagnetic two-spin and antiferromagnetic four-spin
exchange interactions. This behavior gives an interpretation of the double
peaked heat capacity recently observed in monolayer liquid $^3$He adsorbed on a
graphite.


title: Testing AdS/CFT Drag and pQCD Heavy Quark Energy Loss

abstract:
  We present charm and bottom nuclear modification factors for RHIC and LHC
using Standard Model perturbative QCD and recent AdS/CFT string drag energy
loss models. We find that extreme extrapolations to LHC mask potential
experimentally determinable differences in the individual $R_{AA}$s but that
their ratio, $R_{AA}^c/R_{AA}^b$ as a function of transverse momentum is a
remarkably robust observable for finding deviations from either theoretical
framework.


title: Rigorous Approach to the Gravitational Lensing

abstract:
  We revisit a weak gravitational lensing problem by constructing a setup which
describes the actual system as accurately as possible and solving the null
geodesic equations. Details are given for the case of a Universe driven only by
a cosmological constant, \Lambda, which confirm the conventional results: The
conventional lensing analysis is correct as it is, without any need for
correction of O(\Lambda). We also treat the cases of the lensing in generic FRW
backgrounds.


title: Pairing strengths for a two orbital model of the Fe-pnictides

abstract:
  Using an RPA approximation, we have calculated the strengths of the singlet
and triplet pairing interactions which arise from the exchange of spin and
orbital fluctuations for a 2-orbital model of the Fe-pnictide superconductors.
When the system is doped with F, the electron pockets become dominant and we
find that the strongest pairing occurs in the singlet d-wave pairing and the
triplet p-wave pairing channels, which compete closely. The pairing structure
in the singlet d-wave channel corresponds to a superposition of near neighbor
intra-orbital singlets with a minus sign phase difference between the $d_{xz}$
and $d_{yz}$ pairs. The leading pairing configuration in the triplet channel
also involves a nearest neighbor intra-orbital pairing. We find that the
strengths of both the singlet and triplet pairing grow, with the singlet
pairing growing faster, as the onsite Coulomb interaction approaches the value
where the S=1 particle-hole susceptibility diverges.


title: Measuring position and moment together

abstract:
  We describe an operational scheme for determining both the position and
momentum distributions in a large class of quantum states, together with an
experimental implementation.


title:
Wave packet Rabi oscillations from phase-space flow in mesoscopic cavity
  QED

abstract:
  The dynamics of the Jaynes-Cummings Hamiltonian is studied in the
semiclassical limit by reducing it to quantum normal form and deriving the
phase space dynamics of classically smooth observables. The resulting
systematic semiclassical approximation is used to analyze the Rabi oscillations
of a photon wave packet revealing subtle consequences of the uncertainty
principle.


title: W-Extended Fusion Algebra of Critical Percolation

abstract:
  Two-dimensional critical percolation is the member LM(2,3) of the infinite
series of Yang-Baxter integrable logarithmic minimal models LM(p,p'). We
consider the continuum scaling limit of this lattice model as a `rational'
logarithmic conformal field theory with extended W=W_{2,3} symmetry and use a
lattice approach on a strip to study the fundamental fusion rules in this
extended picture. We find that the representation content of the ensuing closed
fusion algebra contains 26 W-indecomposable representations with 8 rank-1
representations, 14 rank-2 representations and 4 rank-3 representations. We
identify these representations with suitable limits of Yang-Baxter integrable
boundary conditions on the lattice and obtain their associated W-extended
characters. The latter decompose as finite non-negative sums of W-irreducible
characters of which 13 are required. Implementation of fusion on the lattice
allows us to read off the fusion rules governing the fusion algebra of the 26
representations and to construct an explicit Cayley table. The closure of these
representations among themselves under fusion is remarkable confirmation of the
proposed extended symmetry.


title: Counterflow Extension for the F.A.S.T.-Model

abstract:
  The F.A.S.T. (Floor field and Agent based Simulation Tool) model is a
microscopic model of pedestrian dynamics, which is discrete in space and time.
It was developed in a number of more or less consecutive steps from a simple CA
model. This contribution is a summary of a study on an extension of the
F.A.S.T-model for counterflow situations. The extensions will be explained and
it will be shown that the extended F.A.S.T.-model is capable of handling
various counterflow situations and to reproduce the well known lane formation
effect.


title: Pion-Photon Transition Distribution Amplitudes

abstract:
  The newly introduced Transition Distribution Amplitudes (TDAs) are discussed
for the $\pi$-$\gamma$ transitions. Relations between $\pi$-$\gamma$ and
$\gamma$-$\pi$ TDAs for different cases are given. Numerical values for the
$\pi$-$\gamma$ TDAs in different models are compared. GPD's features are
extended to TDAs and the role of PCAC highlighted. We give hints for the
evaluation of cross sections for meson pair production in our approach.


title: Integral structures on $p$-adic Fourier theory

abstract:
  In this article, we give an explicit construction of the $p$-adic Fourier
transform by Schneider and Teitelbaum, which allows for the investigation of
the integral property. As an application, we give a certain integral basis of
the space of $K$-locally analytic functions on the ring of integers
$\mathcal{O}_K$ for any finite extension $K$ of $\mathbb{Q}_p$, generalizing
the basis constructed by Amice for locally analytic functions on
$\mathbb{Z}_p$. We also use our result to prove congruences of
Bernoulli-Hurwitz numbers at non-ordinary (i.e. supersingular) primes
originally investigated by Katz and Chellali.


title:
On Torsion-free Vacuum Solutions of the Model of de Sitter Gauge Theory
  of Gravity

abstract:
  It is shown that all vacuum solutions of Einstein field equation with a
positive cosmological constant are the solutions of a model of dS gauge theory
of gravity. Therefore, the model is expected to pass the observational tests on
the scale of solar system and explain the indirect evidence of gravitational
wave from the binary pulsars PSR1913+16.


title: Dark energy and dust matter phases from an exact $f(R)$-cosmology model

abstract:
  We show that dust matter-dark energy combined phases can be achieved by the
exact solution derived from a power law $f(R)$ cosmological model. This example
answers the query by which a dust-dominated decelerated phase, before
dark-energy accelerated phase, is needed in order to form large scale
structures.


title:
Size-selective optical forces for microspheres using evanescent wave
  excitation of whispering gallery modes

abstract:
  We show that when a microsphere is illuminated by an evanescent wave, the
optical forces on- and off- whispering gallery mode (WGM) resonance can differ
by several orders of magnitude. Such size selective force allows one to
selectively manipulate the resonating particles, while leaving those particles
at off-resonance untouched. As WGM resonances have very high-Q's, this kind of
force could be deployed for size-selective manipulation with a very high
accuracy (~1/Q), as well as simultaneous particle-sorting according to their
size or resonant frequency.


title:
Conductance Fluctuations in Disordered Wires with Perfectly Conducting
  Channels

abstract:
  We study conductance fluctuations in disordered quantum wires with unitary
symmetry focusing on the case in which the number of conducting channels in one
propagating direction is not equal to that in the opposite direction. We
consider disordered wires with $N+m$ left-moving channels and $N$ right-moving
channels. In this case, $m$ left-moving channels become perfectly conducting,
and the dimensionless conductance $g$ for the left-moving channels behaves as
$g \to m$ in the long-wire limit. We obtain the variance of $g$ in the
diffusive regime by using the Dorokhov-Mello-Pereyra-Kumar equation for
transmission eigenvalues. It is shown that the universality of conductance
fluctuations breaks down for $m \neq 0$ unless $N$ is very large.


title: The effect of modified gravity on weak lensing

abstract:
  We study the effect of modified gravity on weak lensing in a class of
scalar-tensor theory that includes $f(R)$ gravity as a special case. These
models are designed to satisfy local gravity constraints by having a large
scalar-field mass in a region of high curvature. Matter density perturbations
in these models are enhanced at small redshifts because of the presence of a
coupling $Q$ that characterizes the strength between dark energy and
non-relativistic matter. We compute a convergence power spectrum of weak
lensing numerically and show that the spectral index and the amplitude of the
spectrum in the linear regime can be significantly modified compared to the
$\Lambda$CDM model for large values of $|Q|$ of the order of unity. Thus weak
lensing provides a powerful tool to constrain such large coupling scalar-tensor
models including $f(R)$ gravity.


title:
Computation with Coherent States via Teleportations to and from a
  Quantum Bus

abstract:
  In this paper we present results illustrating the power and flexibility of
one-bit teleportations in quantum bus computation. We first show a scheme to
perform a universal set of gates on continuous variable modes, which we call a
quantum bus or qubus, using controlled phase-space rotations, homodyne
detection, ancilla qubits and single qubit measurement. The resource usage for
this scheme is lower than any previous scheme to date. We then illustrate how
one-bit teleportations into a qubus can be used to encode qubit states into a
quantum repetition code, which in turn can be used as an efficient method for
producing GHZ states that can be used to create large cluster states. Each of
these schemes can be modified so that teleportation measurements are
post-selected to yield outputs with higher fidelity, without changing the
physical parameters of the system.


title: The "Quantum Mousetrap": Entangled States and Gravitational Waves

abstract:
  We propose a "thought technique" for detecting Gravitational Waves using
Einstein-Podolski-Rosen photon Entangled States. GWs decohere the entangled
photon pairs, introduce a relative rotation and de-synchronize Alice and Bob's
reference frames thus reducing the measured non-locality of correlated quanta
described by Bell's inequalities. Gravitational Waves, distorting quantum
encryption key statistics away from a pure white noise, act then as shadow
eavesdroppers. The deviation from the intrinsic white-noise randomness of a
Quantum Key Distribution process can reveal the presence of a gravitational
wave by analyzing the emerging color distortions in the key. Photon entangled
states provide the key advantage of revealing the polarization rotation
introduced by GWs without the need of previously fixed reference frames


title: On the Kerr Quantum Area Spectrum

abstract:
  Suppose that there is a quantum operator that describes the horizon area of a
black hole. Then what would be the form of the ensuing quantum spectrum? In
this regard, it has been conjectured that the characteristic frequencies of the
black hole oscillations can be used to calibrate the spacing between the
spectral levels. The current article begins with a brief review of this
conjecture and some of its subsequent developments. We then suggest a simple
but vital modification to a recent treatment on the Kerr (or rotating black
hole) spectrum. As a consequence of this refinement, we are able to rectify a
prior inconsistency (as was found between two distinct calculations) and to
establish, unambiguously, a universal form for the Kerr and Schwarzschild
spectra.


title: Nonorthogonal Bases and Phase Decomposition: Properties and Applications

abstract:
  In a previous paper [1] it was discussed the viability of functional analysis
using as a basis a couple of generic functions, and hence vectorial
decomposition. Here we complete the paradigm exploiting one of the analysis
methodologies developed there, but applied to phase coordinates, so needing
only one function as a basis. It will be shown that, thanks to the novel
iterative analysis, any function satisfying a rather loose requisite is
ontologically a basis. This in turn generalizes the polar version of the
Fourier theorem to an ample class of nonorthogonal bases. The main advantage of
this generalization is that it inherits some of the properties of the original
Fourier theorem. As a result the new transform has a wide range of applications
and some remarkable consequences. The new tool will be compared with wavelets
and frames. Examples of analysis and reconstruction of functions using the
developed algorithms and generic bases will be given. Some of the properties,
and applications that can promptly benefit from the theory, will be discussed.
The implementation of a matched filter for noise suppression will be used as an
example of the potential of the theory.


title: Cascade Birth of Universes in Multidimensional Spaces

abstract:
  The formation mechanism of universes with distinctly different properties is
considered within the framework of pure gravity in a space of D > 4 dimensions.
The emergence of the Planck scale and its relationship to the inflaton mass are
discussed.


title: State discrimination with error margin and its locality

abstract:
  There are two common settings in a quantum-state discrimination problem. One
is minimum-error discrimination where a wrong guess (error) is allowed and the
discrimination success probability is maximized. The other is unambiguous
discrimination where errors are not allowed but the inconclusive result "I
don't know" is possible. We investigate discrimination problem with a finite
margin imposed on the error probability. The two common settings correspond to
the error margins 1 and 0. For arbitrary error margin, we determine the optimal
discrimination probability for two pure states with equal occurrence
probabilities. We also consider the case where the states to be discriminated
are multipartite, and show that the optimal discrimination probability can be
achieved by local operations and classical communication.


title: Physics of Supernovae: theory, observations, unresolved problems

abstract:
  The main observational properties and resulting classification of supernovae
(SNe) are briefly reviewed. Then we discuss the progress in modeling of two
basic types of SNe - the thermonuclear and core-collapse ones, with special
emphasis being placed on difficulties relating to a consistent description of
thermonuclear flame propagation and the detachment of supernova envelope from
the collapsing core (a nascent neutron star). The properties of the neutrino
flux expected from the corecollapse SNe, and the lessons of SN1987A, exploded
in the Large Magellanic Cloud, are considered as well.


title:
The Clusters AgeS Experiment (CASE). III. Analysis of the Eccentric
  Eclipsing Binary V32 in the Globular Cluster NGC 6397

abstract:
  We present spectroscopic and photometric observations of the eclipsing binary
V32 located in the central field of the globular cluster NGC 6397. The variable
is a single-line spectroscopic binary with an orbital period of 9.8783d and a
large eccentricity of e=0.32. Its systemic velocity (gamma=20.7 km/s) and
metallicity ([Fe/H] -1.9) are both consistent with cluster membership. The
primary component of the binary is located at the top of the main-sequence
turn-off on the cluster color-magnitude diagram. Only a shallow primary eclipse
is observed in the light curve. Based on stellar models for an age of 12Gyr and
the mass-function derived from the radial velocity curve, we estimate the
masses to be M_p=0.79 Msun and M_s=0.23 Msun. The light curve of V32 can be
reproduced by adopting R_p=1.569 Rsun and R_s=0.236 Rsun for the radii and
i=85.44 deg for the system inclination. The system geometry precludes
observations of the secondary eclipse. The large eccentricity of the orbit is
puzzling given that for metal poor, halo binaries the transition from circular
to eccentric orbit occurs at an orbital period of about 20 days. We suppose
that the orbit of V32 was modified relatively recently by dynamical interaction
with other cluster star(s).An alternative explanation of the observed
eccentricity calls for the presence of a third body in the system.


title: Latest results from the PHOBOS experiment

abstract:
  Over the past years PHOBOS has continued to analyze the large datasets
obtained from the first five runs of the Relativistic Heavy Ion Collider (RHIC)
at Brookhaven National Laboratory. The two main analysis streams have been
pursued. The first one aims to obtain a broad and systematic survey of global
properties of particle production in heavy ion collisions. The second class
includes the study of fluctuations and correlations in particle production.
Both type of studies have been performed for a variety of the collision
systems, covering a wide range in collision energy and centrality. The uniquely
large angular coverage of the PHOBOS detector and its ability to measure
charged particles down to very low transverse momentum is exploited. The latest
physics results from PHOBOS, as presented at Quark Matter 2008 Conference, are
contained in this report.


title:
Structural Properties of Ultra-Compact Dwarf Galaxies in the Fornax and
  Virgo Clusters

abstract:
  We present a detailed analysis of two-band HST/ACS imaging of 21
ultra-compact dwarf (UCD) galaxies in the Virgo and Fornax Clusters. The aim of
this work is to test two formation hypotheses for UCDs--whether they are bright
globular clusters (GCs) or "threshed'' early-type dwarf galaxies--by comparison
of UCD structural parameters and colors with GCs and galaxy nuclei. We find
that the UCD surface brightness profiles can be described by a range of models
and that the luminous UCDs can not be described by standard King models with
tidal cutoffs as they have extended outer halos. This is not expected from
traditional King models of GCs, but is consistent with recent results for
massive GCs. The total luminosities, colors and sizes of the UCDs are
consistent with them being either luminous GCs or threshed nuclei of both
early-type and late-type galaxies (not just early-type dwarfs). For the most
luminous UCDs we estimate color gradients over a limited range of radius. These
are systematically positive in the sense of getting redder outwards: mean
Delta(F606W-F814W)=0.14 mag per 100 pc with rms=0.06 mag per 100 pc. The
positive gradients found in the bright UCDs are consistent with them being
either bright GCs or threshed early-type dwarf galaxies (except VUCD3). In
contrast to the above results we find a very significant difference in the
sizes of UCDs and early-type galaxy nuclei: the effective radii of UCDs are 2.2
times larger than those of early-type galaxy nuclei at the same luminosity.
This result suggests an important test can be made of the threshing hypothesis
by simulating the process and predicting what size increase is expected.


title: A note on solitary waves solutions of classical wave equations

abstract:
  The goal of this work is to determine whole classes of solitary wave
solutions general for wave equations.


title: Spectroscopic Mode Identification in Slowly Pulsating Subdwarf-B Stars

abstract:
  Mode identification is crucial for an asteroseismological study of any
significance. Contrarily to spectroscopic techniques, methods such as
period-fitting and multi-colour photometry do not provide a full reconstruction
of non-radial pulsations. We present a new method of spectroscopic mode
identification and test it on time-series of synthetic spectra appropriate for
pulsating subdwarf-B stars. We then apply it to the newly discovered slowly
pulsating subdwarf-B star HD 4539.


title: Community Evolution of Social Network: Feature, Algorithm and Model

abstract:
  Researchers have devoted themselves to exploring static features of social
networks and further discovered many representative characteristics, such as
power law in the degree distribution and assortative value used to
differentiate social networks from nonsocial ones. However, people are not
satisfied with these achievements and more and more attention has been paid on
how to uncover those dynamic characteristics of social networks, especially how
to track community evolution effectively. With these interests, in the paper we
firstly display some basic but dynamic features of social networks. Then on its
basis, we propose a novel core-based algorithm of tracking community evolution,
CommTracker, which depends on core nodes to establish the evolving
relationships among communities at different snapshots. With the algorithm, we
discover two unique phenomena in social networks and further propose two
representative coefficients: GROWTH and METABOLISM by which we are also able to
distinguish social networks from nonsocial ones from the dynamic aspect. At
last, we have developed a social network model which has the capabilities of
exhibiting two necessary features above.


title:
Some more proofs from the Book: solvability and insolvability of
  equations in radicals

abstract:
  This paper is purely expository. We present short elementary proofs of
  * the Gauss Theorem on constructibility of regular polygons;
  * the existence of a cubic equation unsolvable in real radicals;
  * the existence of a quintic equation unsolvable in complex radicals (Galois
Theorem).
  The statements of these celebrated results are simple and well-known.
However, their proofs given in most textbooks rely upon much unmotivated
material and are far from being economic. We do not use the terms `Galois
group' or even `group'. The paper is accessible for students familiar with
polynomials and complex numbers, and could be an interesting easy reading for
professional mathematicians. Short English version is followed by an extended
Russian version where before presenting the proofs we illustrate the main ideas
by sequences of problems with hints or solutions.


title: The $C^{\a}$ regularity of a class hypoelliptic ultraparabolic equations

abstract:
  We obtained the $C^{\a}$ continuity for weak solutions of a class of
ultraparabolic equations with measurable coefficients of the form ${\ptl_t u}=
\sum_{i,j=1}^{m_0}X_i(a_{ij}(x,t)X_j u)+X_0 u$. The result is proved by
simplifying and generalizing our earlier arguments for the $C^{\a}$ regularity
of homogeneous ultraparabolic equations.


title:
Evolution of the genetic code. Why are there strong and weak letter
  doublets? The first gene, the first protein. Early (ancient) biosynthesis of
  protein

abstract:
  The idea of the evolution of the genetic code from the CG to the CGUA
alphabet has been developed further. The assumption of the originally triplet
structure of the genetic code has been substantiated. The hypothesis of the
emergence of stop codons at the early stage of the evolution of the genetic
code has been additionally supported. The existence of strong and weak letter
doublets of codons and the symmetry of strong doublets in the genetic code
table, discovered by Rumer, have been explained. A hypothesis concerning the
primary structure of the first gene and the first protein has been proposed.


title: Lattice Resistance to Dislocation Motion at the Nanoscale

abstract:
  In this letter we propose a model that demonstrates the effect of free
surface on the lattice resistance experienced by a moving dislocation in
nanodimensional systems. This effect manifests in an enhanced velocity of
dislocation due to the proximity of the dislocation line to the surface. To
verify this finding, molecular dynamics simulations for an edge dislocation in
bcc molybdenum are performed and the results are found to be in agreement with
the numerical implementations of this model. The reduction in this effect at
higher stresses and temperatures, as revealed by the simulations, confirms the
role of lattice resistance behind the observed change in the dislocation
velocity.


title: Improving Coverage Accuracy of Block Bootstrap Confidence Intervals

abstract:
  The block bootstrap confidence interval based on dependent data can
outperform the computationally more convenient normal approximation only with
non-trivial Studentization which, in the case of complicated statistics, calls
for highly specialist treatment. We propose two different approaches to
improving the accuracy of the block bootstrap confidence interval under very
general conditions. The first calibrates the coverage level by iterating the
block bootstrap. The second calculates Studentizing factors directly from block
bootstrap series and requires no non-trivial analytic treatment. Both
approaches involve two nested levels of block bootstrap resampling and yield
high-order accuracy with simple tuning of block lengths at the two resampling
levels. A simulation study is reported to provide empirical support for our
theory.


title:
Ergodic Optimal Quadratic Control for an Affine Equation with Stochastic
  and Stationary Coefficients

abstract:
  We study ergodic quadratic optimal stochastic control problems for an affine
state equation with state and control dependent noise and with stochastic
coefficients. We assume stationarity of the coefficients and a finite cost
condition. We first treat the stationary case and we show that the optimal cost
corresponding to this ergodic control problem coincides with the one
corresponding to a suitable stationary control problem and we provide a full
characterization of the ergodic optimal cost and control.


title: System size and energy dependence of $\phi$ meson production at RHIC

abstract:
  We present a system size and energy dependence of $\phi$ meson production in
Cu+Cu and Au+Au collisions at $\sqrt{s_{NN}}$=62.4 GeV and 200 GeV measured by
the STAR experiment at RHIC. We find that the number of participant scaled
$\phi$ meson yields in heavy ion collisions over that of p+p collisions are
larger than 1 and increase with collision energy. We compare the results with
those of open-strange particles and discuss the physics implication.


title:
Bimodal abundance pattern in M51: evidence for corotation resonance
  effects

abstract:
  A chemical evolution model for the bimodal-like abundance distribution in the
external galaxy M51 recently derived on the basis of HST data for more than a
half million red supergiants is developed. It is shown that, like in our
Galaxy, formation of fine structure of the radial abundance pattern -- a rather
steep gradient in the internal part of the disc and a plateau in the middle
part -- is due to the influence of the spiral arms, the bend in the slope of
the distribution being arose near the corotation resonance. Our model strongly
suggests that M51 is surrounded by overabundant gas infalling onto its disc.


title:
Periodic solutions for a class of nonlinear partial differential
  equations in higher dimension

abstract:
  We prove the existence of periodic solutions in a class of nonlinear partial
differential equations, including the nonlinear Schroedinger equation, the
nonlinear wave equation, and the nonlinear beam equation, in higher dimension.
Our result covers cases where the bifurcation equation is infinite-dimensional,
such as the nonlinear Schroedinger equation with zero mass, for which solutions
which at leading order are wave packets are shown to exist.


title: High frequency dynamics in liquid nickel: an IXS study

abstract:
  Owing to their large relatively thermal conductivity, peculiar,
non-hydrodynamic features are expected to characterize the acoustic-like
excitations observed in liquid metals. We report here an experimental study of
collective modes in molten nickel, a case of exceptional geophysical interest
for its relevance in Earth interior science. Our result shed light on
previously reported contrasting evidences: in the explored energy-momentum
region no deviation from the generalized hydrodynamic picture describing non
conductive fluids are observed. Implications for high frequency transport
properties in metallic fluids are discussed.


title: The complex light-curve of the afterglow of GRB071010A

abstract:
  We present and discuss the results of an extensive observational campaign
devoted to GRB071010A, a long-duration gamma-ray burst detected by the Swift
satellite. This event was followed for almost a month in the
optical/near-infrared (NIR) with various telescopes starting from about 2min
after the high-energy event. Swift-XRT observations started only later at about
0.4d. The light-curve evolution allows us to single out an initial rising phase
with a maximum at about 7min, possibly the afterglow onset in the context of
the standard fireball model, which is then followed by a smooth decay
interrupted by a sharp rebrightening at about 0.6d. The rebrightening was
visible in both the optical/NIR and X-rays and can be interpreted as an episode
of discrete energy injection, although various alternatives are possible. A
steepening of the afterglow light curve is recorded at about 1d. The entire
evolution of the optical/NIR afterglow is consistent with being achromatic.
This could be one of the few identified GRB afterglows with an achromatic break
in the X-ray through the optical/NIR bands. Polarimetry was also obtained at
about 1d, just after the rebrightening and almost coincident with the
steepening. This provided a fairly tight upper limit of 0.9% for the
polarized-flux fraction.


title: Coherent spin relaxation in molecular magnets

abstract:
  Numerical modelling of coherent spin relaxation in nanomagnets, formed by
magnetic molecules of high spins, is accomplished. Such a coherent spin
dynamics can be realized in the presence of a resonant electric circuit coupled
to the magnet. Computer simulations for a system of a large number of
interacting spins is an efficient tool for studying the microscopic properties
of such systems. Coherent spin relaxation is an ultrafast process, with the
relaxation time that can be an order shorter than the transverse spin dephasing
time. The influence of different system parameters on the relaxation process is
analysed. The role of the sample geometry on the spin relaxation is
investigated.


title: Long Wave Dynamics along a Convex Bottom

abstract:
  Long linear wave transformation in the basin of varying depth is studied for
a case of a convex bottom profile in the framework of one-dimensional shallow
water equation. The existence of travelling wave solutions in this geometry and
the uniqueness of this wave class is established through construction of a 1:1
transformation of the general 1D wave equation to the analogous wave equation
with constant coefficients. The general solution of the Cauchy problem consists
of two travelling waves propagating in opposite directions. It is found that
generally a zone of a weak current is formed between these two waves. Waves are
reflected from the coastline so that their profile is inverted with respect to
the calm water surface. Long wave runup on a beach with this profile is studied
for sine pulse, KdV soliton and N-wave. Shown is that in certain cases the
runup height along the convex profile is considerably larger than for beaches
with a linear slope. The analysis of wave reflection from the bottom containing
a shallow coastal area of constant depth and a section with the convex profile
shows that a transmitted wave always has a sign-variable shape.


title: Matter on granular space-time

abstract:
  We develop further the formalism of the non-Abelian gauge field theory on a
cell complex space-time and show how the gauge-invariant action and the
equations of motion for gauge fields interacting with spinors can be written
without a reference to the geometrical nature of the cells of the cell complex.
The general results are illustrated with examples of solutions of equations of
motion for U(N) and SU(N) gauge groups.


title: Challenges for asteroseismic analysis of Sun-like stars

abstract:
  Asteroseismology of Sun-like stars is undergoing rapid expansion with, for
example, new data from the CoRoT mission and continuation of ground-based
campaigns. There is also the exciting upcoming prospect of NASA's Kepler
mission, which will allow the asteroseismic study of several hundred Sun-like
targets, in some cases for periods lasting up to a few years. The seismic mode
parameters are the input data needed for making inference on stars and their
internal structures. In this paper we discuss the ease with which it will be
possible to extract estimates of individual mode parameters, dependent on the
mass, age, and visual brightness of the star. Our results are generally
applicable; however, we look at mode detectability in the context of the
upcoming Kepler observations. To inform our discussions we make predictions of
various seismic parameters. To do this we use simple empirical scaling
relations and detailed pulsation computations of the stochastic excitation and
damping characteristics of the Sun-like p modes. The issues related to
parameter extraction on individual p modes discussed here are mode
detectability, the detectability and impact of stellar activity cycles, and the
ability to measure properties of rotationally split components, which is
dependent on the relative importance of the rotational characteristics of the
star and the damping of the stochastically excited p modes.


title:
Inferring population history with DIYABC: a user-friendly approach to
  Approximate Bayesian Computation

abstract:
  Genetic data obtained on population samples convey information about their
evolutionary history. Inference methods can extract this information (at least
partially) but they require sophisticated statistical techniques that have been
made available to the biologist community (through computer programs) only for
simple and standard situations typically involving a small number of samples.
We propose here a computer program (DIYABC) for inference based on Approximate
Bayesian Computation (ABC), in which scenarios can be customized by the user to
fit many complex situations involving any number of populations and samples.
Such scenarios involve any combination of population divergences, admixtures
and stepwise population size changes. DIYABC can be used to compare competing
scenarios, estimate parameters for one or more scenarios, and compute bias and
precision measures for a given scenario and known values of parameters (the
current version applies to unlinked microsatellite data). This article
describes key methods used in the program and provides its main features. The
analysis of one simulated and one real data set, both with complex evolutionary
scenarios, illustrates the main possibilities of DIYABC


title: Noncommutative topological entropy of endomorphisms of Cuntz algebras

abstract:
  Noncommutative topological entropy estimates are obtained for polynomial
gauge invariant endomorphisms of Cuntz algebras, generalising known results for
the canonical shift endomorphisms. Exact values for the entropy are computed
for a class of permutative endomorphisms related to branching function systems
introduced and studied by Bratteli, Jorgensen and Kawamura.


title:
Wave function of particle and the coordinates distribution in
  relativistic quantum theory

abstract:
  The conditions for observation of the particle coordinates, required by logic
of the Special Relativity and filtering the quantum field effects, are
described. A general relation between the corresponding density of probability
and the wave function is found. It is a relativistic invariant describing
probability of the particle emergences in space -time. This density is
concretized for bosons, both scalar and vector (including photon), charged and
neutral, also electron. The Heisenberg's uncertainty relations have been
approved in regards to relativistic particle. As applied to the quantum field,
this new construction is transformed to new characteristic of the particles
distribution in space-time, which complete distribution throughout impulses.
The operators of these distributions and the invariant relativistic description
for free quantum fields have been obtained. These new properties of the
particles and fields are proposed for experimental investigations.


title: A Fast and Flexible Method for the Segmentation of aCGH Data

abstract:
  Motivation: Array Comparative Genomic Hybridization (aCGH) is used to scan
the entire genome for variations in DNA copy number. A central task in the
analysis of aCGH data is the segmentation into groups of probes sharing the
same DNA copy number. Some well known segmentation methods suffer from very
long running times, preventing interactive data analysis. Results: We suggest a
new segmentation method based on wavelet decomposition and thresholding, which
detects significant breakpoints in the data. Our algorithm is over 1,000 times
faster than leading approaches, with similar performance. Another key advantage
of the proposed method is its simplicity and flexibility. Due to its intuitive
structure it can be easily generalized to incorporate several types of side
information. Here we consider two extensions which include side information
indicating the reliability of each measurement, and compensating for a changing
variability in the measurement noise. The resulting algorithm outperforms
existing methods, both in terms of speed and performance, when applied on real
high density CGH data. Availability: Implementation is available under software
tab at: http://www.ee.technion.ac.il/Sites/People/YoninaEldar/ Contact:
yonina@ee.technion.ac.il


title: Fractional Brownian flows

abstract:
  We consider stochastic flow on n-dimensional Euclidean space driven by
fractional Brownian motion with Hurst parameter H greater than half, and study
tangent flow and the growth of the Hausdorff measure of sub-manifolds of the
ambient n-dimensional Euclidean space, as they evolve under the flow. The main
result is a bound on the rate of (global) growth in terms of the (local) Holder
norm of the flow.


title:
The role of carbon segregation on nanocrystallisation of pearlitic
  steels processed by severe plastic deformation

abstract:
  The nanostructure and the carbon distribution in a pearlitic steel processed
by torsion under high pressure was investigated by three-dimensional atom
probe. In the early stage of deformation (shear strain of 62),
off-stoichiometry cementite was analysed close to interphase boundaries and a
strong segregation of carbon atoms along dislocation cell boundaries was
observed in the ferrite. At a shear strain of 300, only few nanoscaled
off-stoichiometry cementite particles remain and a nanoscaled equiaxed grain
structure with a grain size of about 20 nm was revealed. 3D-AP data clearly
point out a strong segregation of carbon atoms along grain boundaries. The
influence of this carbon atom segregation on the nanostructure formation is
discussed and a scenario accounting for the nanocrystallisation during severe
plastic deformation is proposed.


title:
Nanostructure and properties of a Cu-Cr composite processed by severe
  plastic deformation

abstract:
  A Cu-Cr composite was processed by severe plastic deformation to investigate
the role of interphase boundaries on the grain size reduction mechanisms. The
as-deformed material exhibits a grain size of only 20nm. This gives rise to a
dramatic increase of the hardness. Some deformation induced Cu super saturated
solid solutions were clearly exhibited and it is shown that they decrease the
hardness. The formation of such supersaturated solid solution and their
influence on the mechanical properties are discussed.


title: A unique quasi-probability for projective yes-no measurements

abstract:
  From an analysis of projective measurements, it is shown that the Wigner rule
is the unique operational quasi-probability for the post-measurement state. A
unique pre-measurement quasi-probability is derived from a principle of
invariance of measurement disturbance under orthogonal projector
complementation. Physical arguments for this principle are given. The
informationally complete complex extension of the quasi-probability is also
derived. Nonclassicality of this quasi-probability is due to measurement
disturbance. The same quasi-probability follows from weak measurements.


title:
Tachyon Vacuum Solution in Open String Field Theory with Constant B
  Field

abstract:
  We show that Schnabl's tachyon vacuum solution is an exact solution of the
equation of motion of Witten's open bosonic string field theory in the
background of constant antisymmetric two-form field. The action computed at the
vacuum solution is given by the Dirac-Born-Infeld factor multiplied to that
without the antisymmetric tensor field.


title:
Anisotropy of Galactic Cosmic Rays and New Discoveries in Its
  Measurements

abstract:
  We discuss recently published results of two-dimensional measurements of the
cosmic ray anisotropy in the energy range 1-100 TeV. It is demonstrated that,
in spite of pretence of the authors to measure the anisotropy in more detail
than it was done in one-dimensional measurements of the first harmonic of CR
intensity in sidereal time, new measurements give nothing essentially new.
Moreover, two-dimensional picture is misleading creating an illusion that the
true direction of the anisotropy is observed, while, as before, only the
projection of the anisotropy onto the equatorial plane is measured and the
phase of the anisotropy remains to be the only directly measured parameter. The
sophisticated interpretations of the results of 2D measurements made by their
authors are invalid, since they are based on the false assumption that the
equatorial excess and deficit of CR intensity seen on the difference maps
represent the real anisotropy.


title: Boundary Shape and Casimir Energy

abstract:
  Casimir energy changes are investigated for geometries obtained by small but
arbitrary deformations of a given geometry for which the vacuum energy is
already known for the massless scalar field. As a specific case, deformation of
a spherical shell is studied. From the deformation of the sphere we show that
the Casimir energy is a decreasing function of the surface to volume ratio. The
decreasing rate is higher for less smooth deformations.


title:
Practical Automated Partial Verification of Multi-Paradigm Real-Time
  Models

abstract:
  This article introduces a fully automated verification technique that permits
to analyze real-time systems described using a continuous notion of time and a
mixture of operational (i.e., automata-based) and descriptive (i.e.,
logic-based) formalisms. The technique relies on the reduction, under
reasonable assumptions, of the continuous-time verification problem to its
discrete-time counterpart. This reconciles in a viable and effective way the
dense/discrete and operational/descriptive dichotomies that are often
encountered in practice when it comes to specifying and analyzing complex
critical systems. The article investigates the applicability of the technique
through a significant example centered on a communication protocol. More
precisely, concurrent runs of the protocol are formalized by parallel instances
of a Timed Automaton, while the synchronization rules between these instances
are specified through Metric Temporal Logic formulas, thus creating a
multi-paradigm model. Verification tests run on this model using a bounded
validity checker implementing the technique show consistent results and
interesting performances.


title: Linear-Programming Decoding of Nonbinary Linear Codes

abstract:
  A framework for linear-programming (LP) decoding of nonbinary linear codes
over rings is developed. This framework facilitates linear-programming based
reception for coded modulation systems which use direct modulation mapping of
coded symbols. It is proved that the resulting LP decoder has the
'maximum-likelihood certificate' property. It is also shown that the decoder
output is the lowest cost pseudocodeword. Equivalence between pseudocodewords
of the linear program and pseudocodewords of graph covers is proved. It is also
proved that if the modulator-channel combination satisfies a particular
symmetry condition, the codeword error rate performance is independent of the
transmitted codeword. Two alternative polytopes for use with linear-programming
decoding are studied, and it is shown that for many classes of codes these
polytopes yield a complexity advantage for decoding. These polytope
representations lead to polynomial-time decoders for a wide variety of
classical nonbinary linear codes. LP decoding performance is illustrated for
the [11,6] ternary Golay code with ternary PSK modulation over AWGN, and in
this case it is shown that the performance of the LP decoder is comparable to
codeword-error-rate-optimum hard-decision based decoding. LP decoding is also
simulated for medium-length ternary and quaternary LDPC codes with
corresponding PSK modulations over AWGN.


title: Some global minimizers of a symplectic Dirichlet energy

abstract:
  The variational problem for the functional
$F=\frac12\|\phi^*\omega\|_{L^2}^2$ is considered, where $\phi:(M,g)\to
(N,\omega)$ maps a Riemannian manifold to a symplectic manifold. This
functional arises in theoretical physics as the strong coupling limit of the
Faddeev-Hopf energy, and may be regarded as a symplectic analogue of the
Dirichlet energy familiar from harmonic map theory. The Hopf fibration
$\pi:S^3\to S^2$ is known to be a locally stable critical point of $F$. It is
proved here that $\pi$ in fact minimizes $F$ in its homotopy class and this
result is extended to the case where $S^3$ is given the metric of the Berger's
sphere. It is proved that if $\phi^*\omega$ is coclosed then $\phi$ is a
critical point of $F$ and minimizes $F$ in its homotopy class. If $M$ is a
compact Riemann surface, it is proved that every critical point of $F$ has
$\phi^*\omega$ coclosed. A family of holomorphic homogeneous projections into
Hermitian symmetric spaces is constructed and it is proved that these too
minimize $F$ in their homotopy class.


title: Early dynamics of transversally thermalized matter

abstract:
  We argue that the idea that the parton system created in relativistic
heavy-ion collisions is formed in a state with transverse momenta close to
thermodynamic equilibrium and its subsequent dynamics at early times is
dominated by pure transverse hydrodynamics of the perfect fluid is compatible
with the data collected at RHIC. This scenario of early parton dynamics may
help to solve the problem of early equilibration.


title:
Interfacial contribution to the dielectric response in semiconducting
  LaBiMn4/3Co2/3O6

abstract:
  Impedance measurements have been performed on a sintered polycrystalline
sample of the perovskite LaBiMn4/3Co2/3O6. Colossal dielectric permittivity
often is measured in this class of semiconducting materials as a result of
extrinsic factors. Our results show that a large offset in the capacitance,
measured on a series of samples with different thickness, is due to the
interfacial polarization. This contribution then can be removed from the data,
creating a general procedure for dielectric measurements in semiconducting
samples.


title: On the Finsler metrics obtained as limits of chessboard structures

abstract:
  We study the geodesics in a planar chessboard structure with two values 1 and
$\beta>1$. The results for a fixed structure allow us to infer the properties
of the Finsler metrics obtained, with an homogenization procedure, as limit of
oscillating chessboard structures.


title: NLO QCD corrections to pp -> top anti-top + jet + X

abstract:
  We discuss the production of top--anti-top quark pairs in association with a
hard jet at the Tevatron and at the LHC and we report on the calculation of the
next-to-leading order QCD corrections to this process. Numerical results for
the top--anti-top+jet cross section and the forward--backward charge asymmetry
are presented. The corrections stabilize the leading-order prediction for the
cross section. In contrast, the charge asymmetry receives large corrections.
The dependence of the cross section as well as the asymmetry on the minimum
transverse momenta used to define the additional jet is studied in detail for
the Tevatron.


title: Properties of the Dwarf Galaxy Population in Galaxy Clusters

abstract:
  We present the observational properties of the dwarf galaxy population (Mr >
M*+1) corresponding to one of the largest samples of spectroscopically
confirmed galaxy cluster members reported in the literature. We have observed
that red dwarf galaxies (u-r > 2.22) share the same cluster environment as the
brightest cluster members (Mr < -21), but are not in dynamical equilibrium. We
computed the dwarf-to-giant ratio (DGR) using a spectroscopically selected
sample. The DGR was found to vary with clustercentric distance, essentially due
to the blue dwarf population (u-r < 2.22). The u-r color of red dwarf galaxies
was independent of their environment and similar to the color of red isolated
dwarfs. Blue dwarf galaxies located outside r200 show similar u-r colors to
those of the field population, while strong reddening was observed toward the
cluster center. We also present evidence that the fraction of red to blue dwarf
galaxies in clusters is larger in the innermost cluster regions. We conclude
that the present red dwarf population observed in the central regions of nearby
galaxy clusters could be related to the blue dwarf population observed in
clusters at high redshift.


title: A Lower Bound on the Bayesian MSE Based on the Optimal Bias Function

abstract:
  A lower bound on the minimum mean-squared error (MSE) in a Bayesian
estimation problem is proposed in this paper. This bound utilizes a well-known
connection to the deterministic estimation setting. Using the prior
distribution, the bias function which minimizes the Cramer-Rao bound can be
determined, resulting in a lower bound on the Bayesian MSE. The bound is
developed for the general case of a vector parameter with an arbitrary
probability distribution, and is shown to be asymptotically tight in both the
high and low signal-to-noise ratio regimes. A numerical study demonstrates
several cases in which the proposed technique is both simpler to compute and
tighter than alternative methods.


title:
Current without bias and diode effect in shuttling transport of
  nanoshafts

abstract:
  A row of parallely ordered and coupled molecular nanoshafts is shown to
develop a shuttling transport of charges at finite temperature. The appearance
of a cu rrent without applying an external bias voltage is reported as well as
a natura l diode effect allowing unidirectional charge transport along one
field directi on while blocking the opposite direction. The zero-bias voltage
current appears above a threshold of initial thermal and/or dislocation energy.


title:
Color intensity projections provides a fast, simple and robust method of
  summarizing the grayscale images from a renal scan in a single color image

abstract:
  To assess its usefulness, the peak version of color intensity projections
(CIPs) was used to display a summary of the grayscale images composing a
renogram as a single color image. Method For each pixel in a renogram, the time
point with the maximum intensity was used to control the hue of the color of
the corresponding pixel in the CIPs image. The hue ranged over
red-yellow-green-light blue-blue with red representing the earliest time.
Results For subjects with normal appearing kidneys, the injection site shows up
in red, the kidneys in a red-yellow and the bladder in a green-blue. A late
fill kidney typically appeared greener or bluer than a normal kidney indicating
it reached its peak intensity at a later time point than normal. Conclusions
Having the time and intensity information summarized in a single image promises
to speed up the initial impression of patients by less experienced interpreters
and should also provide a valuable training tool.


title: An Optical Counterpart Candidate for the Isolated Neutron Star RBS1774

abstract:
  Multiwavelength studies of the seven identified X-ray dim isolated neutron
stars (XDINSs) offer a unique opportunity to investigate their surface thermal
and magnetic structure and the matter-radiation interaction in presence of
strong gravitational and magnetic fields. As a part of an ongoing campaign
aimed at a complete identification and spectral characterization of XDINSs in
the optical band, we performed deep imaging with the ESO Very Large Telescope
(VLT) of the field of the XDINS RBS1774 (1RXS J214303.7 +065419). The recently
upgraded FORS1 instrument mounted on the VLT provided the very first detection
of a candidate optical counterpart in the B band. The identification is based
on a very good positional coincidence with the X-ray source (chance probability
~2E-3). The source has B=27.4 +/- 0.2 (1 sigma confidence level), and the
optical flux exceeds the extrapolation of the X-ray blackbody at optical
wavelengths by a factor ~35 (+/- 20 at 3sigma confidence level). This is barely
compatible with thermal emission from the neutron star surface, unless the
source distance is d~200-300 pc, and the star is an almost aligned rotator or
its spin axis is nearly aligned with the line of sight. At the same time, such
a large optical excess appears difficult to reconcile with rotation-powered
magnetospheric emission, unless the source has an extremely large optical
emission efficiency. The implications and possible similarities with the
optical spectra of other isolated NSs are discussed.


title:
Development of a peristaltic micropump for bio-medical applications
  based on mini LIPCA

abstract:
  This paper presents the design, fabrication, and experimental
characterization of a peristaltic micropump. The micropump is composed of two
layers fabricated from polydimethylsiloxane (PDMS) material. The first layer
has a rectangular channel and two valve seals. Three rectangular mini
lightweight piezo-composite actuators are integrated in the second layer, and
used as actuation parts. Two layers are bonded, and covered by two polymethyl
methacrylate (PMMA) plates, which help increase the stiffness of the micropump.
A maximum flow rate of 900 mokroliter per min and a maximum backpressure of 1.8
kPa are recorded when water is used as pump liquid. We measured the power
consumption of the micropump. The micropump is found to be a promising
candidate for bio-medical application due to its bio-compatibility,
portability, bidirectionality, and simple effective design.


title:
Efficient ion blocking in gaseous detectors and its application to
  gas-avalanche photomultipliers sensitive in the visible-light range

abstract:
  A novel concept for ion blocking in gas-avalanche detectors was developed,
comprising cascaded micro-hole electron multipliers with patterned electrodes
for ion defocusing. This leads to ion blocking at the 10^{-4} level, in DC
mode, in operation conditions adequate for TPCs and for gaseous
photomultipliers. The concept was validated in a cascaded visible-sensitive gas
avalanche photomultiplier operating at atmospheric pressure of Ar/CH_{4} (95/5)
with a bi-alkali photocathode. While in previous works high gain, in excess of
10^{5}, was reached only in a pulse-gated cascaded-GEM gaseous photomultiplier,
the present device yielded, for the first time, similar gain in DC mode. We
describe shortly the physical processes involved in the charge transport within
gaseous photomultipliers and the ion blocking method. We present results of ion
backflow fraction and of electron multiplication in cascaded
patterned-electrode gaseous photomultiplier with K-Cs-Sb, Na-K-Sb and Cs-Sb
visible-sensitive photocathodes, operated in DC mode.


title:
Symmetry and holomorphy of the third-order ordinary differential
  equation satisfied by the third Painlev\'e Hamiltonian

abstract:
  We study symmetry and holomorphy of the third-order ordinary differential
equation satisfied by the third Painlev\'e Hamiltonian.


title:
Op\'erateurs d'entrelacement et alg\`ebres de Hecke avec param\`etres
  d'un groupe r\'eductif $p$-adique - le cas des groupes classiques

abstract:
  For $G$ a symplectic or orthogonal $p$-adic group (not necessarily split), or
an inner form of a general linear $p$-adic group, we compute the endomorphism
algebras of some induced projective generators \`a la Bernstein of the category
of smooth representations of $G$ and show that these algebras are isomorphic to
the semi-direct product of a Hecke algebra with parameters by a finite group
algebra. Our strategy and parts of our intermediate results apply to a general
reductive connected $p$-adic group.


title: Mixed Hodge Structures and Renormalization in Physics

abstract:
  We relate renormalization in perturbative quantum field theory to the theory
of limiting mixed Hodge structures using parametric representations of Feynman
graphs.


title: Tensor Operators in Noncommutative Quantum Mechanics

abstract:
  Some consequences of promoting the object of noncommutativity ${\mathbf
\theta}^{ij}$ to an operator in Hilbert space are explored. Consequently, a
consistent algebra involving the enlarged set of canonical operators is
obtained, which permits us to construct theories that are dynamically invariant
under the action of the rotation group. In this framework it is also possible
to give dynamics to the noncommutativity operator sector, resulting in new
features.


title: Higgs at LHC

abstract:
  An overview of recent theoretical results on the Higgs boson and its
discovery strategy at ATLAS and CMS will be presented, focusing on the main
Higgs analysis effective with low integrated luminosity (less than 30 fb^-1).


title:
Complete inclusion of parity-dependent level densities in the
  statistical description of astrophysical reaction rates

abstract:
  Microscopic calculations show a strong parity dependence of the nuclear level
density at low excitation energy of a nucleus. Previously, this dependence has
either been neglected or only implemented in the initial and final channels of
Hauser-Feshbach calculations. We present an indirect way to account for a full
parity dependence in all steps of a reaction, including the one of the compound
nucleus formed in a reaction. To illustrate the impact on astrophysical
reaction rates, we present rates for neutron captures in isotopic chains of Ni
and Sn. Comparing with the standard assumption of equipartition of both
parities, we find noticeable differences in the energy regime of astrophysical
interest caused by the parity dependence of the nuclear level density found in
the compound nucleus even at sizeable excitation energies.


title: Families of vector fields which generate the group of diffeomorphisms

abstract:
  Given a compact manifold M, we prove that any bracket generating and
invariant under multiplication on smooth functions family of vector fields on M
generates the connected component of unit of the group Diff(M).


title:
A weak energy identity and the length of necks for a Sacks-Uhlenbeck
  $\alpha$-harmonic map sequence

abstract:
  We will give a weak energy identity for Sacks-Uhlenbeck approximation of
harmonic maps and calculate the length of the necks.


title: Tensor Coordinates in Noncommutative Mechanics

abstract:
  A consistent classical mechanics formulation is presented in such a way that,
under quantization, it gives a noncommutative quantum theory with interesting
new features. The Dirac formalism for constrained Hamiltonian systems is
strongly used, and the object of noncommutativity ${\mathbf \theta}^{ij}$ plays
a fundamental rule as an independent quantity. The presented classical theory,
as its quantum counterpart, is naturally invariant under the rotation group
$SO(D)$.


title:
Evolution of spin entanglement and an entanglement witness in
  multiple-quantum NMR experiments

abstract:
  We investigate the evolution of entanglement in multiple-quantum (MQ) NMR
experiments in crystals with pairs of close nuclear spins-1/2. The initial
thermodynamic equilibrium state of the system in a strong external magnetic
field evolves under the non-secular part of the dipolar Hamiltonian. As a
result, MQ coherences of the zeroth and plus/minus second orders appear. A
simple condition for the emergence of entanglement is obtained. We show that
the measure of the spin pair entanglement, concurrence, coincides qualitatively
with the intensity of MQ coherences of the plus/minus second order and hence
the entanglement can be studied with MQ NMR methods. We introduce an
Entanglement Witness using MQ NMR coherences of the plus/minus second order.


title:
Search for direct photons in p+Pb and p+C collisions at sqrt(sNN) = 17.4
  GeV

abstract:
  Upper limits on direct photon production were determined as a function of the
transverse momentum for 0.7 < pT <= 3.2 GeV/c with the WA98 experiment in p+C
and p+Pb collisions at sqrt(sNN) = 17.4 GeV. The results are compared to direct
photon measurements in Pb+Pb collisions at sqrt(sNN) = 17.3 GeV by WA98.
Implications for a possible thermal direct photon contribution are discussed.


title: Jet Propagation and Mach Cones in (3+1)d Ideal Hydrodynamics

abstract:
  The observation of jet quenching and associated away--side Mach cone--like
correlations at RHIC provide powerful ``external'' probes of the sQGP produced
in A+A reactions, but it simultaneously raises the question where the jet
energy was deposited. The nearly perfect bulk fluidity observed via elliptic
flow suggests that Mach cone--like correlations may also be due to rapid local
equilibration in the wake of penetrating jets. Multi-particle correlations lend
further support to this possibility. However, a combined study of energy
deposition and fluid response is needed. We solve numerically 3--dimensional
ideal hydrodynamical equations to compute the flow correlation patterns
resulting from a variety of possible energy-momentum deposition models.
Mach--cone correlations are shown to depend critically on the energy and
momentum deposition mechanisms. They only survive for a special limited class
of energy--momentum loss models, which assume significantly less longitudinal
momentum loss than energy loss per unit length. We conclude that the correct
interpretation of away--side jet correlations will require improved
understanding and independent experimental constraints on the jet
energy--momentum loss to fluid couplings.


title:
Thermal conductivity and phase separation of the crust of accreting
  neutron stars

abstract:
  Recently, crust cooling times have been measured for neutron stars after
extended outbursts. These observations are very sensitive to the thermal
conductivity $\kappa$ of the crust and strongly suggest that $\kappa$ is large.
We perform molecular dynamics simulations of the structure of the crust of an
accreting neutron star using a complex composition that includes many
impurities. The composition comes from simulations of rapid proton capture
nucleosynthesys followed by electron captures. We find that the thermal
conductivity is reduced by impurity scattering. In addition, we find phase
separation. Some impurities with low atomic number $Z$ are concentrated in a
subregion of the simulation volume. For our composition, the solid crust must
separate into regions of different compositions. This could lead to an
asymmetric star with a quadrupole deformation that radiates gravitational
waves. Observations of crust cooling can constrain impurity concentrations.


title: An Equivalence Relation on A Set of Words of Finite Length

abstract:
  In this work, we study several equivalence relations induced from the
partitions of the sets of words of finite length. We have results on words over
finite fields extending the work of Bacher (2002, Europ. J. Combinatorics, {\bf
23}, 141-147). Cardinalities of its equivalence classes and explicit
relationships between two words are determined. Moreover, we deal with words of
finite length over the ring $\mathbb{Z}/N\mathbb{Z}$ where $N$ is a positive
integer. We have arithmetic results parallel to Bacher's.


title: Experimental quantum tossing of a single coin

abstract:
  The cryptographic protocol of coin tossing consists of two parties, Alice and
Bob, that do not trust each other, but want to generate a random bit. If the
parties use a classical communication channel and have unlimited computational
resources, one of them can always cheat perfectly. Here we analyze in detail
how the performance of a quantum coin tossing experiment should be compared to
classical protocols, taking into account the inevitable experimental
imperfections. We then report an all-optical fiber experiment in which a single
coin is tossed whose randomness is higher than achievable by any classical
protocol and present some easily realisable cheating strategies by Alice and
Bob.


title: Angular Distributions in the Decays B -> K* l+l-

abstract:
  We use a sample of 384 million BBbar events collected with the Babar detector
at the PEP-II e+e- collider to study angular distributions in the rare decays B
-> K* l+l-, where l+l- is either e+e- or mu+mu-. For low dilepton invariant
masses, m(l+l-)<2.5 GeV/c^2, we measure a lepton forward-backward asymmetry
AFB=0.24 (+0.18,-0.23) +/- 0.05 and K* longitudinal polarization FL=0.35 +/-
0.16 +/- 0.04$. For m(l+l-)>3.2$ GeV/c^2, we measure AFB=0.76 (+0.52,-0.32) +/-
0.07 FL=0.71 (+0.20,-0.22) +/- 0.04.


title: Recombination limited energy relaxation in a BCS superconductor

abstract:
  We study quasiparticle energy relaxation at sub-kelvin temperatures by
injecting hot electrons into an aluminium island and measuring the energy flux
from electrons into phonons both in the superconducting and in the normal
state. The data show strong reduction of the flux at low temperatures in the
superconducting state, in qualitative agreement with the presented
quasiclassical theory for clean superconductors. Quantitatively, the energy
flux exceeds that from the theory both in the superconducting and in the normal
state, possibly suggesting an enhanced or additional relaxation process.


title: Schnabl's Solution and Boundary States in Open String Field Theory

abstract:
  We discuss that Schnabl's solution is an off-shell extension of the boundary
state describing a D-brane in the closed string sector. It gives the physical
meaning of the gauge invariant overlaps for the solution in our previous paper
and supports Ellwood's recent proposal in the operator formalism.


title: Eppstein's bound on intersecting triangles revisited

abstract:
  Let S be a set of n points in the plane, and let T be a set of m triangles
with vertices in S. Then there exists a point in the plane contained in
Omega(m^3 / (n^6 log^2 n)) triangles of T. Eppstein (1993) gave a proof of this
claim, but there is a problem with his proof. Here we provide a correct proof
by slightly modifying Eppstein's argument.


title: Jahn-Teller systems from a cavity QED perspective

abstract:
  Jahn-Teller systems and the Jahn-Teller effect are discussed in terms of
cavity QED models. By expressing the field modes in a quadrature
representation, it is shown that certain setups of a two-level system
interacting with a bimodal cavity is described by the Jahn-Teller
$E\times\epsilon$ Hamiltonian. We identify the corresponding adiabatic
potential surfaces and the conical intersection. The effects of a non-zero
geometrical Berry phase, governed by encircling the conical intersection, are
studied in detail both theoretically and numerically. The numerical analysis is
carried out by applying a wave packet propagation method, more commonly used in
molecular or chemical physics, and analytic expressions for the characteristic
time scales are presented. It is found that the collapse-revival structure is
greatly influenced by the geometrical phase and as a consequence, the field
intensities contain direct information about this phase. We also mention the
link between the Jahn-Teller effect and the Dicke phase transition in cavity
QED.


title:
Identifying the underlying physics of the ridge via 3-particle
  $\Delta\eta-\Delta\eta$ correlations

abstract:
  We present the first results on 3-particle $\Delta\eta$-$\Delta\eta$
correlations in minimum bias $d$+Au, peripheral and central Au+Au collisions at
$\sqrt{{\it s}_{NN}}$ = 200 GeV measured by the STAR experiment. The analysis
technique is described in detail. The ridge particles, observed at large
$\Delta\eta$ in dihadron correlations in central Au+Au collisions, appear to be
uniformly distributed over the measured $\Delta\eta$-$\Delta\eta$ region in
3-particle correlation. The results, together with theoretical models, should
help further our understanding of the underlying physics of the ridge.


title: Infinitely many conservation laws in self-dual Yang--Mills theory

abstract:
  Using a nonlocal field transformation for the gauge field known as
Cho--Faddeev--Niemi--Shabanov decomposition as well as ideas taken from
generalized integrability, we derive a new family of infinitely many conserved
currents in the self-dual sector of SU(2) Yang-Mills theory. These currents may
be related to the area preserving diffeomorphisms on the reduced target space.
The calculations are performed in a completely covariant manner and, therefore,
can be applied to the self-dual equations in any space-time dimension with
arbitrary signature.


title: One-dimensional extended Hubbard model in the atomic limit

abstract:
  We present the exact solution of the one-dimensional extended Hubbard model
in the atomic limit within the Green's function and equation of motion
formalism. We provide a comprehensive and systematic analysis of the model by
considering all the relevant response and correlation functions as well as
thermodynamic quantities in the whole parameter space. At zero temperature we
identify four phases in the plane (U,n) [U is the onsite potential and n is the
filling] and relative phase transitions as well as different types of charge
ordering. These features are endorsed by investigating at T=0 the chemical
potential and pertinent local correlators, the particle and double occupancy
correlation functions, the entropy, and by studying the behavior in the limit T
going to zero of the charge and spin susceptibilities. A detailed study of the
thermodynamic quantities is also presented at finite temperature. This study
evidences that a finite-range order persists for a wide range of the
temperature, as shown by the behavior of the correlation functions and by the
two-peak structure exhibited by the charge susceptibility and by the entropy.
Moreover, the equation of motion formalism, together with the use of composite
operators, allows us to exactly determine the set of elementary excitations. As
a result, the density of states can be determined exactly and a detailed
analysis of the specific heat allows for identifying the excitations and for
ascribing its two-peak structure to a redistribution of the charge density.


title:
The diamond-alpha Riemann integral and mean value theorems on time
  scales

abstract:
  We study diamond-alpha integrals on time scales. A diamond-alpha version of
Fermat's theorem for stationary points is also proved, as well as Rolle's,
Lagrange's, and Cauchy's mean value theorems on time scales.


title:
Self-consistent simulations of Nuclear Cluster formation through
  Globular Cluster orbital decay and merging

abstract:
  We present results of fully self-consistent N-body simulations of the motion
of four globular clusters moving in the inner region of their parent galaxy.
With regard to previous simplified simulations, we confirm merging and
formation of an almost steady nuclear cluster, in a slightly shorter time. The
projected surface density profile shows strong similarity to that of resolved
galactic nuclei. This similarity reflects also in the velocity dispersion
profile which exhibits a central colder component as observed in many nucleated
galaxies.


title: Fermi Liquid instabilities in two-dimensional lattice models

abstract:
  We develop a procedure for detecting Fermi liquid instabilities by extending
the analysis of Pomeranchuk to two-dimensional lattice systems. The method is
very general and straightforward to apply, thus providing a powerful tool for
the search of exotic phases. We test it by applying it to a lattice electron
model with interactions leading to $s$ and d-wave instabilities.


title:
A closed-form energy-minimization basis for gravity field source
  estimation: DIDACKS IV

abstract:
  By building on the field energy minimization underpinnings of DIDACKS theory
and by making certain natural assumptions about the general nature of the
energy/density configuration of the Earth's interior it is shown that the
problem of estimating the Earth's interior density, either globally or locally,
can be naturally reframed as a energy minimization one. The basic idea is that
a static stable density configuration is a minimum energy configuration, which
tends to be unique (when all other things are equal); hence, a field energy
minimization approach can be counted on to generally lead to a physically
motivated unique solution. Techniques touched on should provide practical
implementation tools, or at least some helpful hints, for handling many of the
well-known ill-posedness issues associated with mass density estimation and
other related inverse-source Laplacian problems.


title:
Generalized parton distributions and Deeply Virtual Compton Scattering
  in Color Glass Condensate model

abstract:
  Within the framework of the Color Glass Condensate model, we evaluate quark
and gluon Generalized Parton Distributions (GPDs) and the cross section of
Deeply Virtual Compton Scattering (DVCS) in the small-$x_{B}$ region. We
demonstrate that the DVCS cross section becomes independent of energy in the
limit of very small $x_{B}$, which clearly indicates saturation of the DVCS
cross section. Our predictions for the GPDs and the DVCS cross section at
high-energies can be tested at the future Electron-Ion Collider and in
ultra-peripheral nucleus-nucleus collisions at the LHC.


title: A stochastic Keller-Segel model of chemotaxis

abstract:
  We introduce stochastic models of chemotaxis generalizing the deterministic
Keller-Segel model. These models include fluctuations which are important in
systems with small particle numbers or close to a critical point. Following
Dean's approach, we derive the exact kinetic equation satisfied by the density
distribution of cells. In the mean field limit where statistical correlations
between cells are neglected, we recover the Keller-Segel model governing the
smooth density field. We also consider hydrodynamic and kinetic models of
chemotaxis that take into account the inertia of the particles and lead to a
delay in the adjustment of the velocity of cells with the chemotactic gradient.
We make the connection with the Cattaneo model of chemotaxis and the telegraph
equation.


title: On homology classes not representable by products

abstract:
  This paper has been withdrawn, because it is subsumed by the new preprint
arXiv:0806.4540 .


title: The isometry group of L^{p}(\mu,\X) is SOT-contractible

abstract:
  We will show that if (\Omega,\Sigma,\mu) is an atomless positive measure
space, X is a Banach space and 1\leq p<\infty, then the group of isometric
automorphisms on the Bochner space L^{p}(\mu,X) is contractible in the strong
operator topology. We do not require \Sigma or X above to be separable.


title: The intrinsic asymmetry and inhomogeneity of Teichmuller space

abstract:
  Royden proved that any isometry of Teichmuller space in the Teichmuller
metric must be an element of the extended mapping class group M(S). He also
proved that the Teichmuller metric is not symmetric at any point. In this paper
we give extensions of Royden's theorems from the Teichmuller metric to an
arbitrary complete, finite covolume, M(S)-invariant Finsler (e.g. Riemannian)
metric on Teichmuller space. In particular this gives a new mechanism behind
Royden's original theorem.


title: Numerical simulations of rotating axisymmetric sunspots

abstract:
  A numerical model of axisymmetric convection in the presence of a vertical
magnetic flux bundle and rotation about the axis is presented. The model
contains a compressible plasma described by the nonlinear MHD equations, with
density and temperature gradients simulating the upper layer of the sun's
convection zone. The solutions exhibit a central magnetic flux tube in a
cylindrical numerical domain, with convection cells forming collar flows around
the tube. When the numerical domain is rotated with a constant angular
velocity, the plasma forms a Rankine vortex, with the plasma rotating as a
rigid body where the magnetic field is strong, as in the flux tube, while
experiencing sheared azimuthal flow in the surrounding convection cells,
forming a free vortex. As a result, the azimuthal velocity component has its
maximum value close to the outer edge of the flux tube. The azimuthal flow
inside the magnetic flux tube and the vortex flow are prograde relative to the
rotating cylindrical reference frame. A retrograde flow appears at the outer
wall. The most significant convection cell outside the flux tube is the
location for the maximum value of the azimuthal magnetic field component. The
azimuthal flow and magnetic structure are not generated spontaneously, but
decay exponentially in the absence of any imposed rotation of the cylindrical
domain.


title: Decoherence in dc SQUID phase qubits

abstract:
  We report measurements of Rabi oscillations and spectroscopic coherence times
in an Al/AlOx/Al and three Nb/AlOx/Nb dc SQUID phase qubits. One junction of
the SQUID acts as a phase qubit and the other junction acts as a
current-controlled nonlinear isolating inductor, allowing us to change the
coupling to the current bias leads in situ by an order of magnitude. We found
that for the Al qubit a spectroscopic coherence time T2* varied from 3 to 7 ns
and the decay envelope of Rabi oscillations had a time constant T' = 25 ns on
average at 80 mK. The three Nb devices also showed T2* in the range of 4 to 6
ns, but T' was 9 to 15 ns, just about 1/2 the value we found in the Al device.
For all the devices, the time constants were roughly independent of the
isolation from the bias lines, implying that noise and dissipation from the
bias leads were not the principal sources of dephasing and inhomogeneous
broadening.


title:
Volume Laws for Boxed Plane Partitions and Area Laws for Ferrers
  Diagrams

abstract:
  We asymptotically analyse the volume-random variables of general, symmetric
and cyclically symmetric plane partitions fitting inside a box. We consider the
respective symmetry class equipped with the uniform distribution. We also prove
area limit laws for two ensembles of Ferrers diagrams. Most of the limit laws
are Gaussian.


title: Branching Fractions for Transitions of psi(2S) to J/psi

abstract:
  We report determination of branching fractions for the decays psi(2S) --> h +
J/psi, where h=any, pi+pi-, pi0pi0, eta, pi0, and gamma gamma through
chi_{c0,1,2}. These measurements use 27M psi(2S) decays produced in e+e-
collision data collected with the CLEO detector. The resulting branching
fractions and ratios thereof improve upon previously achieved precision in all
cases, and in combination with other measurements permit determination of
B(chi_cJ --> gamma J/psi) and B(psi(2S) --> light hadrons).


title: SPACE: the SPectroscopic All-sky Cosmic Explorer

abstract:
  We describe the scientific motivations, the mission concept and the
instrumentation of SPACE, a class-M mission proposed for concept study at the
first call of the ESA Cosmic-Vision 2015-2025 planning cycle. SPACE aims to
produce the largest three-dimensional evolutionary map of the Universe over the
past 10 billion years by taking near-IR spectra and measuring redshifts for
more than half a billion galaxies at 0<z<2 down to AB~23 over 3\pi sr of the
sky. In addition, SPACE will also target a smaller sky field, performing a deep
spectroscopic survey of millions of galaxies to AB~26 and at 2<z<10+. These
goals are unreachable with ground-based observations due to the ~500 times
higher sky background. To achieve the main science objectives, SPACE will use a
1.5m diameter Ritchey-Chretien telescope equipped with a set of arrays of
Digital Micro-mirror Devices (DMDs) covering a total field of view of 0.4 deg2,
and will perform large-multiplexing multi-object spectroscopy (e.g. ~6000
targets per pointing) at a spectral resolution of R~400 as well as
diffraction-limited imaging with continuous coverage from 0.8mum to 1.8mum.


title: Probabilistic Embedding Of Discrete Sets As Continuous Metric Spaces

abstract:
  Any symmetric affinity function $w: V\times V \to \mathbb{R}_+$ defined on a
discrete set $V$ induces Euclidean space structure on $V$. In particular, an
undirected graph specified by an affinity (or adjacency) matrix can be
considered as a metric topological space. We have calculated the visual
representations of the probabilistic locus for a chain, a polyhedron, and a
finite 2-dimensional lattice.


title:
Spherically symmetric trapping horizons, the Misner-Sharp mass and black
  hole evaporation

abstract:
  Understood in terms of pure states evolving into mixed states, the
possibility of information loss in black holes is closely related to the global
causal structure of spacetime, as is the existence of event horizons. However,
black holes need not be defined by event horizons, and in fact we argue that in
order to have a fully unitary evolution for black holes, they should be defined
in terms of something else, such as a trapping horizon. The Misner-Sharp mass
in spherical symmetry shows very simply how trapping horizons can give rise to
black hole thermodynamics, Hawking radiation and singularities. We show how the
Misner-Sharp mass can also be used to give insights into the process of
collapse and evaporation of locally defined black holes.


title: Uniqueness Theorems for Point Source Expansions: DIDACKS V

abstract:
  Finite collections of point masses contained in some bounded domain produce a
unique field in the exterior domain, which means that the associated basis
functions (often called ``fundamental solutions'') are independent. A new proof
of this result is given in this paper that can be generalized to other finite
combinations of point source distributions. For example, this paper shows in
$\mathbb{R}^3$ that a finite combination of point dipoles produces a unique
field. The strategy employed in the paper is to develop results for analytic
functions in the complex plane and then carry them over to harmonic functions
in the real plane, and from there to harmonic functions in $\mathbb{R}^3$. More
results are shown for $\mathbb{R}^2$ and for $\mathbb{C}$ than are shown for
more general settings. For example, in the complex plane, the paper shows that
a finite combination of higher order poles of any order in the interior of a
unit disk always corresponds to a unique analytic function in the exterior of a
unit disk.


title:
Singlet-triplet dispersion reveals additional frustration in the
  triangular dimer compound Ba$_3$Mn$_2$O$_8$

abstract:
  We present single crystal inelastic neutron scattering measurements of the
S=1 dimerized quasi-two-dimensional antiferromagnet Ba$_3$Mn$_2$O$_8$. The
singlet-triplet dispersion reveals nearest-neighbor and next-nearest-neighbor
ferromagnetic interactions between adjacent bilayers that compete against each
other. Although the inter-bilayer exchange is comparable to the intra-bilayer
exchange, this additional frustration reduces the effective coupling along the
c-axis and leads to a quasi-two dimensional behavior. In addition, the obtained
exchange values are able to reproduce the four critical fields in the phase
diagram.


title: On the Chern number of a filtration

abstract:
  We study the first Hilbert coefficient (after the multiplicity) $e_1$ of a
local ring $(A,\m). $ Under various circumstances, it is also called the {\bf
Chern number} of the local ring $A.$ Starting from the work of D.G. Northcott
in the 60's, several results have been proved which give some relationships
between the Hilbert coefficients, but always assuming the Cohen-Macaulayness of
the basic ring. Recent papers of S. Goto, K. Nishida, A. Corso and W.
Vasconcelos pushed the interest toward a more general setting. In this paper we
extend an upper bound on $e_1$ proved by S. Huckaba and T. Marley. Thus we get
the Cohen-Macaulayness of the ring $A$ as a consequence of the extremal
behavior of the integer $e_1.$ The result can be considered a confirm of the
general philosophy of the paper of W. Vasconcelos where the Chern number is
conjectured to be a measure of the distance from the Cohen-Macaulyness of $A.$
This main result of the paper is a consequence of a nice and perhaps unexpected
property of superficial elements. It is essentially a kind of "Sally machine"
for local rings. In the last section we describe an application of these
results, concerning an upper bound on the multiplicity of the Sally module of a
good filtration of a module which is not necessarily Cohen-Macaulay. It is an
extension to the non Cohen-Macaulay case of a result of Vaz Pinto.


title:
Photometric and Spectroscopic study of a highly reddened type Ia
  supernova SN 2003hx in NGC 2076

abstract:
  We present $UBVRI$ CCD photometry and optical spectra of the type Ia
supernova SN 2003hx which appeared in the galaxy NGC 2076, obtained till $\sim$
146 days after the epoch of $B$ band maximum. The supernova reached at maximum
brightness in $B$ band on JD 245 2893 $\pm$ 1.0 with an apparent magnitude of
14.92 $\pm$ 0.01 mag which was estimated by making template fits to the light
curves. SN 2003hx is an example of a highly reddened supernova with $E(B-V)$ =
0.56 $\pm$ 0.23. We estimate $R_v$ = 1.97 $\pm$ 0.54 which indicates the small
size of dust particles as compared to their galactic counterparts. The
luminosity decline rate is $\Delta m_{15}(B)$ = 1.17 $\pm$ 0.12 mag and the
absolute $B$ band magnitude obtained from the luminosity versus decline rate
relation (Phillips et al. 1999) is $M^B_{max}$ = -19.20 $\pm$ 0.18 mag. The
peak bolometric luminosity indicates that $\sim$ 0.66 $M_\odot$ mass of $^{56}$
Ni was ejected by the supernova. The spectral evolution indicates the supernova
to be a normal type Ia event.


title: Palatini versus metric formulation in higher curvature gravity

abstract:
  We compare the metric and the Palatini formalism to obtain the Einstein
equations in the presence of higher-order curvature corrections that consist of
contractions of the Riemann tensor, but not of its derivatives. We find that
there is a class of theories for which the two formalisms are equivalent. This
class contains the Palatini version of Lovelock theory, but also more
Lagrangians that are not Lovelock, but respect certain symmetries. For the
general case, we find that imposing the Levi-Civita connection as an Ansatz,
the Palatini formalism is contained within the metric formalism, in the sense
that any solution of the former also appears as a solution of the latter, but
not necessarily the other way around. Finally we give the conditions the
solutions of the metric equations should satisfy in order to solve the Palatini
equations.


title:
Existence and regularity of a nonhomogeneous transition matrix under
  measurability conditions

abstract:
  This paper is about the existence and regularity of the transition
probability matrix of a nonhomogeneous continuous-time Markov process with a
countable state space. A standard approach to prove the existence of such a
transition matrix is to begin with a continuous (in t) and conservative matrix
Q(t)=[q_{ij}(t)] of nonhomogeneous transition rates q_{ij}(t), and use it to
construct the transition probability matrix. Here we obtain the same result
except that the q_{ij}(t) are only required to satisfy a mild measurability
condition, and Q(t) may not be conservative. Moreover, the resulting transition
matrix is shown to be the minimum transition matrix and, in addition, a
necessary and sufficient condition for it to be regular is obtained. These
results are crucial in some applications of nonhomogeneous continuous-time
Markov processes, such as stochastic optimal control problems and stochastic
games, which motivated this work in the first place.


title:
Minimal free resolution of a finitely generated module over a regular
  local ring

abstract:
  Numerical invariants of a minimal free resolution of a module $M$ over a
regular local ring $(R,\n)$ can be studied by taking advantage of the rich
literature on the graded case. The key is to fix suitable $\n$-stable
filtrations ${\mathbb M} $ of $M $ and to compare the Betti numbers of $M$ with
those of the associated graded module $ gr_{\mathbb M}(M). $ This approach has
the advantage that the same module $M$ can be detected by using different
filtrations on it. It provides interesting upper bounds for the Betti numbers
and we study the modules for which the extremal values are attained. Among
others, the Koszul modules have this behavior. As a consequence of the main
result, we extend some results by Aramova, Conca, Herzog and Hibi on the
rigidity of the resolution of standard graded algebras to the local setting.