title:
Yield correlations and $p_T$ dependence of charm hadrons in Pb + Pb
  collisions at $\sqrt{s_{NN}}= 2.76$ TeV

abstract:
  Recently the ALICE Collaboration has published a few data of charm hadrons in
Pb + Pb collisions at the CERN Large Hadron Collider (LHC). We extend the quark
combination to the charm sector and point out that the measurement of charm
hadron yields can provide important insights into charm quark hadronization
mechanism and properties of the hot and dense matter produced in high energy
reactions. We propose several types of yield ratios, e.g. $D^{*+}/D^0$,
$D_s^+/D^+$ and $\Lambda_c^+/D_s^+$, to measure various properties of low $p_T$
charm quark hadronization. We argue that ratios $D_s^+/D^0$ and
$2D_s^+/(D^0+D^+)$ as the function of transverse momentum can serve as good
probes for the dynamics of charm quark hadronization. We further make
predictions for the yields and $p_T$ spectra of identified charm hadrons in
central Pb + Pb collisions at $\sqrt{s_{NN}}= 2.76$ TeV.


title:
Associated symmetric pair and multiplicities of admissible restriction
  of Discrete Series

abstract:
  Let $(G, H)$ be a symmetric pair for a real semisimple Lie group $G$ and $(G,
H_0)$ its associated pair. For each irreducible square integrable
representation $\pi$ of $G$ so that its restriction to $H$ is admissible, we
find an irreducible square integrable representation $\pi_0$ of $H_0$ which
allows to compute the Harish-Chandra parameter of each irreducible
$H-$subrepresentation of $\pi$ as well as its multiplicity. The computation is
based on the spectral analysis of the restriction of $\pi_0$ to a maximal
compact subgroup of $H_0.$


title:
Problems in Systematic Application of Software Metrics and Possible
  Solution

abstract:
  Systematic application of software metric techniques can lead to significant
improvements of the quality of a final software product. However, there is
still the evident lack of wider utilization of software metrics techniques and
tools due to many reasons. In this paper we investigate some limitations of
contemporary software metrics tools and then propose construction of a new tool
that would solve some of the problems. We describe the promising prototype, its
internal structure, and then focus on its independency of the input language.


title: Lower bounds on the Graver complexity of $M$-fold matrices

abstract:
  In this paper, we present a construction that turns certain relations on
Graver basis elements of an $M$-fold matrix $A^{(M)}$ into relations on Graver
basis elements of an $(M+1)$-fold matrix $A^{(M+1)}$. In doing so, we
strengthen the bound on the Graver complexity of the $M$-fold matrix
$A_{3\times M}$ from $g(A_{3\times M})\geq 17\cdot 2^{M-3}-7$ (Berstein and
Onn) to $g(A_{3\times M})\geq 24\cdot 2^{M-3}-21$, for $M\geq 4$. Moreover, we
give a lower bound on the Graver complexity $g(A^{(M)})$ of general $M$-fold
matrices $A^{(M)}$ and we prove that the bound for $g(A_{3\times M})$ is not
tight.


title: Fractional Charge and Confinement of Quarks

abstract:
  In quantum chromodynamics with static quarks the confinement-deconfinement
phase transition is connected to the spontaneous breaking of the global Z3
center symmetry. This symmetry is lost when one considers dynamical quarks.
Owing to the fractional electric charge of quarks, we recover a global Z6
center symmetry when QCD is regarded as a part of the Standard Model. We
present results from QCD-like theories extended by electromagnetic interactions
and show that the weak coupling limit of the QED part of the model results in a
center-like symmetry with disorder in the vacuum. This can be seen explicitly
in a character expansion of the fermion determinant. Further, we show that
corresponding center averages project the fermion determinant on N-ality zero
and discuss whether the additional center symmetry can be used to eliminate the
fermion sign problem in QCD with fundamental quarks.


title: Cauchy-Schwarz inequality and particle entanglement

abstract:
  The Glauber-Sudarshan $P$-representation is used in quantum optics to
distinguish between semi-classical and genuinely quantum electromagnetic
fields. We employ the analog of the $P$-representation to show that the
violation of the Cauchy-Schwarz inequality for the second-order correlation
function is a proof of entanglement between identical massive bosons. The
presented derivation is valid both in systems with fixed and fluctuating number
of particles. Thanks to the recent advances in techniques of detecting
positions of separate particles, the violation of the Cauchy-Schwarz inequality
can be used as a simple entanglement criterion in various many-body quantum
systems.


title: Cosmological evidence for leptonic asymmetry after Planck

abstract:
  Recently, the Planck satellite found a larger and most precise value of the
matter energy density, that impacts on the present values of other cosmological
parameters such as the Hubble constant, the present cluster abundances and the
age of the Universe. The existing tension between Planck determination of these
parameters in the frame of the base LambdaCDM model and their direct
measurements generated lively discussions and several interpretations. In this
paper we quantify this tension by exploring several extensions of the base
LambdaCDM model that include the leptonic asymmetry. We set bounds on the
radiation content of the Universe and neutrino properties by using the latest
cosmological measurements, imposing also self-consistent BBN constraints on the
primordial helium abundance. For all cosmological asymmetric models we find the
preference of cosmological data for smaller values of active and sterile
neutrino masses. This increases the tension between cosmological and short
baseline neutrino oscillation data that favor a sterile neutrino with the mass
of around 1 eV. For the case of degenerate massive neutrinos, we find that the
discrepancies with direct determinations of the Hubble constant, the present
cluster abundances and the age of the Universe are alleviated at ~ 1.3 sigma
for all leptonic asymmetric models. We also find ~2 sigma statistical evidence
of the preference of cosmological data for the normal neutrino hierarchy. This
is more evident for the case of cosmological models involving leptonic
asymmetry and three massive neutrino species. We conclude that the current
cosmological data favor the leptonic asymmetric extension of the base LambdaCDM
model and normal neutrino mass hierarchy over the models with additional
sterile neutrino species and/or inverted neutrino mass hierarchy.


title:
A liquid-gas transition for bosons with attractive interaction in one
  dimension

abstract:
  We consider a one dimensional system of $N$ bosons interacting via an
attractive Dirac delta function potential. We place the bosonic quantum
particles at thermal equilibrium in a box of length $L$ with periodic boundary
conditions. At large $N$ and for $L$ much larger than the diameter of a two
particle bound state, we predict by numerical and analytical studies of a
simple model derived from first principles that the system exhibits a first
order phase transition in a high temperature, non-degenerate regime. The higher
temperature phase is an almost pure atomic gas, with a small fraction of
dimers, a smaller fraction of trimers, etc. The lower temperature phase is a
mesoscopic or macroscopic bound state that collects all the particles of the
system with the exception of a small gaseous fraction composed mainly of atoms.
We term this phase, which is the quantum equivalent of the classical bright
soliton, a liquid.---Nous considerons, en dimension un, une assemblee de $N$
particules quantiques bosoniques interagissant par un potentiel de Dirac
attractif, a l'equilibre thermique dans une boite de quantification de longueur
L avec des conditions aux limites periodiques. Pour de grandes valeurs de N, et
lorsque L est bien superieur au diametre de l'etat dimere dans l'espace reel,
nous predisons, par etude numerique et analytique d'un modele simple mais
deduit des premiers principes, que le systeme presente, a haute temperature
c'est-a-dire dans le regime non degenere, une transition du premier ordre entre
deux phases. La phase privilegiee a haute temperature est un gaz presque pur
d'atomes, avec une faible fraction de dimeres, et des fractions encore plus
faibles de trimeres, etc. La phase qui la supplante a moins haute temperature
est un etat lie mesoscopique ou macroscopique que nous qualifions de liquide,
equivalent quantique du soliton brillant de la theorie de champ classique, et
qui renferme toutes les particules du systeme, a l'exception d'une petite
fraction gazeuse composee essentiellement d'atomes.


title:
Un algorithme de d\'ebruitage Non-Local means espace-fr\'equence (A
  space-frequency Non-Local means image denoising algorithm)

abstract:
  The efficiency of the Non-Local means (NLM) image denoising algorithm relies
on the identification of similar original pixels from noisy similar patches.
Hence fine details and low-contrasted structures are badly recovered after the
application of NLM. But as these structures tend to correspond to redundant
ones in the Fourier domain, NLM filtering in this domain allows one to better
denoise them. A mixed space-frequency approach improves the denoising
performances of NLM because it ensures that the information is redundant
enough, in the spatial domain or in the frequency domain. Our approach is
simple : it consists in running two times the NLM algorithm (firstly in the
frequency domain and secondly in the spatial domain). For fine textures and
isolated points we get a better visual reconstruction than with the original
NLM. In terms of PSNR, the improvement can be over 1 dB. Our approach gives
intermediate results between the original NLM and state-of-the-art methods
while at the same time having moderate complexity and leading to few visual
artifacts.


title: Mapping cognitive ontologies to and from the brain

abstract:
  Imaging neuroscience links brain activation maps to behavior and cognition
via correlational studies. Due to the nature of the individual experiments,
based on eliciting neural response from a small number of stimuli, this link is
incomplete, and unidirectional from the causal point of view. To come to
conclusions on the function implied by the activation of brain regions, it is
necessary to combine a wide exploration of the various brain functions and some
inversion of the statistical inference. Here we introduce a methodology for
accumulating knowledge towards a bidirectional link between observed brain
activity and the corresponding function. We rely on a large corpus of imaging
studies and a predictive engine. Technically, the challenges are to find
commonality between the studies without denaturing the richness of the corpus.
The key elements that we contribute are labeling the tasks performed with a
cognitive ontology, and modeling the long tail of rare paradigms in the corpus.
To our knowledge, our approach is the first demonstration of predicting the
cognitive content of completely new brain images. To that end, we propose a
method that predicts the experimental paradigms across different studies.


title:
Transport properties of Ag5Pb2O6: a three-dimensional electron-gas-like
  system with low-carrier-density

abstract:
  We report normal-state transport properties of the single-crystalline samples
of the silver-lead oxide superconductor Ag5Pb2O6, including the electrical
resistivity, magnetoresistance, and Hall coefficient. From the Hall coefficient
measurement, we confirmed that the carrier density of this oxide is as low as
5x10^{21} cm^{-3}, one order of magnitude smaller than those for ordinary
alkali metals and noble metals. The magnetoresistance behavior is well
characterized by the axial symmetry of the Fermi surface and by a single
relaxation time. The T^2 term of the resistivity is scaled with the specific
heat coefficient, based on the recent theory for the electron-electron
scattering. The present results provide evidence that Ag5Pb2O6 is a
low-carrier-density three-dimensional electron-gas-like system with enhanced
electron-electron scatterings.


title: Deformation of Gabor systems

abstract:
  We introduce a new notion for the deformation of Gabor systems. Such
deformations are in general nonlinear and, in particular, include the standard
jitter error and linear deformations of phase space. With this new notion we
prove a strong deformation result for Gabor frames and Gabor Riesz sequences
that covers the known perturbation and deformation results. Our proof of the
deformation theorem requires a new characterization of Gabor frames and Gabor
Riesz sequences. It is in the style of Beurling's characterization of sets of
sampling for bandlimited functions and extends significantly the known
characterization of Gabor frames "without inequalities" from lattices to
non-uniform sets.


title:
Generalized oscillator representations for generalized Calogero
  Hamiltonians

abstract:
  This paper is a natural continuation of the previous paper \cite{TyuVo13}
where generalized oscillator representations for Calogero Hamiltonians with
potential $V(x)=\alpha/x^2$, $\alpha\geq-1/4$, were constructed. In this paper,
we present generalized oscillator representations for all generalized Calogero
Hamiltonians with potential $V(x)=g_{1}/x^2+g_{2}x^2$, $g_{1}\geq-1/4$,
$g_{2}>0$. These representations are generally highly nonunique, but there
exists an optimum representation for each Hamiltonian, representation that
explicitly determines the ground state and the ground-state energy. For
generalized Calogero Hamiltonians with coupling constants $g_1<-1/4$ or
$g_2<0$, generalized oscillator representations do not exist in agreement with
the fact that the respective Hamiltonians are not bounded from below.


title:
Influence of the ab-initio nd cross sections in the critical heavy-water
  benchmarks

abstract:
  The n-d elastic and breakup cross sections are computed by solving the
three-body Faddeev equations for realistic and semi-realistic Nucleon-Nucleon
potentials. These cross sections are inserted in the Monte Carlo simulation of
the nuclear processes considered in the International Handbook of Evaluated
Criticality Safety Benchmark Experiments (ICSBEP). The results obtained using
thes ab initio n-d cross sections are compared with those provided by the most
renown international libraries.


title:
Frequency-based image analysis of random patterns: an alternative way to
  classical stereocorrelation

abstract:
  The paper presents an alternative way to classical stereocorrelation. First,
2D image processing of random patterns is described. Sub-pixel displacements
are determined using phase analysis. Then distortion evaluation is presented.
The distortion is identified without any assumption on the lens model because
of the use of a grid technique approach. Last, shape measurement and shape
variation is caught by fringe projection. Analysis is based on two pin-hole
assumptions for the video-projector and the camera. Then, fringe projection is
coupled to in-plane displacement to give rise to 3D measurement set-up.
Metrological characterization shows a resolution comparable to classical
(stereo) correlation technique (1/100th pixel). Spatial resolution seems to be
an advantage of the method, because of the use of temporal phase stepping
(shape measurement, 1 pixel) and windowed Fourier transform (in plane
displacements measurement, 9 pixels). Two examples are given. First one is the
study of skin properties; second one is a study on leather fabric. In both
cases, results are convincing, and have been exploited to give mechanical
interpretation.


title: The gas-phase chemistry of carbon chains in dark cloud chemical models

abstract:
  We review the reactions between carbon chain molecules and radicals, namely
Cn, CnH, CnH2, C2n+1O, CnN, HC2n+1N, with C, N and O atoms. Rate constants and
branching ratios for these processes have been re-evaluated using experimental
and theoretical literature data. In total 8 new species have been introduced,
41 new reactions have been proposed and 122 rate coefficients from
kida.uva.2011 (Wakelam et al. 2012) have been modified. We test the effect of
the new rate constants and branching ratios on the predictions of gas-grain
chemical models for dark cloud conditions using two different C/O elemental
ratios. We show that the new rate constants produce large differences in the
predicted abundances of carbon chains since the formation of long chains is
less effective. The general agreement between the model predictions and
observed abundances in the dark cloud TMC-1 (CP) is improved by the new network
and we find that C/O ratios of 0.7 and 0.95 both produce a similar agreement
for different times. The general agreement for L134N (N) is not significantly
changed. The current work specifically highlights the importance of O + CnH and
N + CnH reactions. As there are very few experimental or theoretical data for
the rate constants of these reactions we highlight the need for experimental
studies of the O + CnH and N + CnH reactions, particularly at low temperature.


title: Short and biased introduction to groupoids

abstract:
  The algebraic part of approach to groupoids started by S. Zakrzewski is
presented.


title: The Robber Locating game

abstract:
  We consider a game in which a cop searches for a moving robber on a graph
using distance probes, studied by Carragher, Choi, Delcourt, Erickson and West,
which is a slight variation on one introduced by Seager. Carragher, Choi,
Delcourt, Erickson and West show that for any fixed graph $G$ there is a
winning strategy for the cop on the graph $G^{1/m}$, obtained by replacing each
edge of $G$ by a path of length $m$, if $m$ is sufficiently large. They
conjecture that the cop does not have a winning strategy on $K_n^{1/m}$ if
$m<n$; we show that in fact the cop wins if and only if $m\geqslant n/2$, for
all but a few small values of $n$. They also show that the robber can avoid
capture on any graph of girth 3, 4 or 5, and ask whether there is any graph of
girth 6 on which the cop wins. We show that there is, but that no such graph
can be bipartite; in the process we give a counterexample for their conjecture
that the set of graphs on which the cop wins is closed under the operation of
subdividing edges. We also give a complete answer to the question of when the
cop has a winning strategy on $K_{a,b}^{1/m}$.


title: On the automorphism groups of binary linear codes

abstract:
  Let C be a binary linear code and suppose that its automorphism group
contains a non trivial subgroup G. What can we say about C knowing G? In this
paper we collect some answers to this question in the cases G=C_p, G=C_2p and
G=D_2p (p an odd prime), with a particular regard to the case in which C is
self-dual. Furthermore we generalize some methods used in other papers on this
subject. Finally we give a short survey on the problem of determining the
automorphism group of a putative self-dual [72,36,16] code, in order to show
where these methods can be applied.


title:
The effect of the substrate on the Raman and photoluminescence emission
  of single layer MoS2

abstract:
  We quantitatively study the Raman and photoluminescence (PL) emission from
single layer molybdenum disulfide (MoS2) on dielectric (SiO2, hexagonal boron
nitride, mica and the polymeric dielectric Gel-Film) and conducting substrates
(Au and few-layer graphene). We find that the substrate can affect the Raman
and PL emission in a twofold manner. First, the absorption and emission
intensities are strongly modulated by the constructive/destructive interference
within the different substrates. Second, the position of the A1g Raman mode
peak and the spectral weight between neutral and charged excitons in the PL
spectra are modified by the substrate. We attribute this effect to
substrate-induced changes in the doping level and in the decay rates of the
excitonic transitions. Our results provide a method to quantitatively study the
Raman and PL emission from MoS2-based vertical heterostructures and represent
the first step in ad-hoc tuning the PL emission of 1L MoS2 by selecting the
proper substrate.


title:
New Exclusion Limits on Dark Gauge Forces from Proton Bremsstrahlung in
  Beam-Dump Data

abstract:
  We re-analyze published proton beam dump data taken at the U70 accelerator at
IHEP Serpukhov with the $\nu$-calorimeter I experiment in 1989 to set
mass-coupling limits for dark gauge forces. The corresponding data have been
used for axion and light Higgs particle searches in Refs.
\cite{Blumlein:1990ay,Blumlein:1991xh} before. More recently, limits on dark
gauge forces have been derived from this data set, considering a dark photon
production from $\pi^0$-decay \cite{Blumlein:2011mv}. Here we determine
extended mass and coupling exclusion bounds for dark gauge bosons ranging to
masses $m_{\gamma'}$ of 624 MeV at admixture parameters $\varepsilon \simeq
10^{-6}$ considering high-energy Bremsstrahlung of the $U$-boson off the
initial proton beam and different detection mechanisms.


title: Financial interaction networks inferred from traded volumes

abstract:
  In order to use the advanced inference techniques available for Ising models,
we transform complex data (real vectors) into binary strings, by local
averaging and thresholding. This transformation introduces parameters, which
must be varied to characterize the behaviour of the system. The approach is
illustrated on financial data, using three inference methods -- equilibrium,
synchronous and asynchronous inference -- to construct functional connections
between stocks. We show that the traded volume information is enough to obtain
well known results about financial markets, which use however the presumably
richer price information: collective behaviour ("market mode") and strong
interactions within industry sectors. Synchronous and asynchronous Ising
inference methods give results which are coherent with equilibrium ones, and
more detailed since the obtained interaction networks are directed.


title: Lyapunov functions, shadowing, and topological stability

abstract:
  We use Lyapunov type functions to give new conditions under which a
homeomorphism of a compact metric space has the shadowing property. These
conditions are applied to establish the topological stability of some
homeomorphisms with nonhyperbolic behavior.


title: Updated constraints on non-standard neutrino interactions from Planck

abstract:
  We provide updated bounds on non-standard neutrino interactions based on data
from the Planck satellite as well as auxiliary cosmological measurements. Two
types of models are studied - A Fermi-like 4-point interaction and an
interaction mediated by a light pseudoscalar - and we show that these two
models are representative of models in which neutrinos either decouple or
recouple in the early Universe. Current cosmological data constrain the
effective 4-point coupling to be $G_X \leq \left(0.06 \, {\rm
GeV}\right)^{-2}$, corresponding to $G_X \leq 2.5 \times 10^7 G_F$. For
non-standard pseudoscalar interactions we set a limit on the diagonal elements
of the dimensionless coupling matrix, $g_{ij}$, of $g_{ii} \leq 1.2 \times
10^{-7}$. For the off-diagonal elements which induce neutrino decay the bound
is significantly stronger, corresponding to $g_{ij} \leq 2.3 \times
10^{-11}(m/0.05 \, {\rm eV})^{-2}$, or a lifetime constraint of $\tau \geq 1.2
\times 10^{9} \, {\rm s} \, (m/0.05 \, {\rm eV})^{3} \,$. This is currently the
strongest known bound on this particular type of neutrino decay. We finally
note that extremely strong neutrino self-interactions which completely suppress
anisotropic stress over all of cosmic history are very highly disfavored by
current data ($\Delta \chi^2 \sim 10^4$).


title: An Algorithm to Solve the Equal-Sum-Product Problem

abstract:
  A recursive algorithm is constructed which finds all solutions to a class of
Diophantine equations connected to the problem of determining ordered n-tuples
of positive integers satisfying the property that their sum is equal to their
product. An examination of the use of Binary Search Trees in implementing the
algorithm into a working program is given. In addition an application of the
algorithm for searching possible extra exceptional values of the
equal-sum-product problem is explored after demonstrating a link between these
numbers and the Sophie Germain primes.


title: Some thoughts on dynamic effective properties -- a working document

abstract:
  The main purpose of this work is to address the question of the utility of
"effective constitutive relations" for problems in dynamics. This is done in
the context of longitudinal shear waves in an elastic medium that is
periodically laminated, with attention restricted to plane waves propagating in
the direction normal to the interfaces. The properties of such waves can be
found by employing Floquet theory, implemented via a "transfer matrix"
formulation. Problems occur at frequencies beyond those that define the first
pass band, associated in part with the difficulty of assigning a unique
wavenumber to the wave. This problem is examined, paying careful attention to
the requirements of causality and passivity. The transmission of waves into a
half-space is discussed by studying the impedance of the half-space, both
directly and in the "effective medium" approximation, and an alternative way of
looking at this problem, based on construction of the Green's function, is
developed.


title:
Optimizing the basis of B -> K* l+l- observables and understanding its
  tensions

abstract:
  We discuss the impact of recent LHCb data on the B -> K* mu+mu- decay for New
Physics searches. We use an optimised set of observables with a limited
sensitivity to hadronic inputs (form factors), leading to a significant
deviation from the Standard Model for the semileptonic operator O9. We
ascertain the robustness of our results with respect to models of power
corrections, charm-loop effects, factorisation approaches, possible effects
from resonance tails at low-recoil, choice of observables and binnings. We
explain some contradictory results obtained for the chirality-flipped operator
O9prime by different analyses by focusing on the sensitivity of observables at
low recoil afflicted by the psi(4160) and possibly other resonances for B+-> K+
mu+mu- and illustrating the need for a finely binned analysis at large recoil
(rather than a wide [1-6] bin). Finally, we present updated results including
experimental correlations in B -> K* mu+ mu- observables, confirming the
deviation seen with respect to the SM hypothesis (4.2 sigma for large-recoil
data, 3.5 sigma for large- and low-recoil data).


title: Optimal Networks from Error Correcting Codes

abstract:
  To address growth challenges facing large Data Centers and supercomputing
clusters a new construction is presented for scalable, high throughput, low
latency networks. The resulting networks require 1.5-5 times fewer switches,
2-6 times fewer cables, have 1.2-2 times lower latency and correspondingly
lower congestion and packet losses than the best present or proposed networks
providing the same number of ports at the same total bisection. These advantage
ratios increase with network size. The key new ingredient is the exact
equivalence discovered between the problem of maximizing network bisection for
large classes of practically interesting Cayley graphs and the problem of
maximizing codeword distance for linear error correcting codes. Resulting
translation recipe converts existent optimal error correcting codes into
optimal throughput networks.


title:
Solutions to position-dependent mass quantum mechanics for a new class
  of hyperbolic potentials

abstract:
  We analytically solve the position-dependent mass (PDM) 1D Schr\"odinger
equation for a new class of hyperbolic potentials $V_q^p(x) =
-V_0\frac{\sinh^px}{\cosh^qx}, \, p= -2, 0, \dots q$ [see C. A. Downing, J.
Math. Phys. 54 072101 (2013)] among which several hyperbolic single- and
double-wells. For a solitonic mass distribution, $m(x)=m_0\,\text{sech}^2(x)$,
we obtain exact analytic solutions to the resulting differential equations. For
several members of the class, the quantum mechanical problems map into
confluent Heun differential equations. The PDM Poschl-Teller potential is
considered and exactly solved as a particular case.


title: Answering SPARQL queries modulo RDF Schema with paths

abstract:
  SPARQL is the standard query language for RDF graphs. In its strict
instantiation, it only offers querying according to the RDF semantics and would
thus ignore the semantics of data expressed with respect to (RDF) schemas or
(OWL) ontologies. Several extensions to SPARQL have been proposed to query RDF
data modulo RDFS, i.e., interpreting the query with RDFS semantics and/or
considering external ontologies. We introduce a general framework which allows
for expressing query answering modulo a particular semantics in an homogeneous
way. In this paper, we discuss extensions of SPARQL that use regular
expressions to navigate RDF graphs and may be used to answer queries
considering RDFS semantics. We also consider their embedding as extensions of
SPARQL. These SPARQL extensions are interpreted within the proposed framework
and their drawbacks are presented. In particular, we show that the PSPARQL
query language, a strict extension of SPARQL offering transitive closure,
allows for answering SPARQL queries modulo RDFS graphs with the same complexity
as SPARQL through a simple transformation of the queries. We also consider
languages which, in addition to paths, provide constraints. In particular, we
present and compare nSPARQL and our proposal CPSPARQL. We show that CPSPARQL is
expressive enough to answer full SPARQL queries modulo RDFS. Finally, we
compare the expressiveness and complexity of both nSPARQL and the corresponding
fragment of CPSPARQL, that we call cpSPARQL. We show that both languages have
the same complexity through cpSPARQL, being a proper extension of SPARQL graph
patterns, is more expressive than nSPARQL.


title: Groupoid Actions on Fractafolds

abstract:
  We define a bundle over a totally disconnected set such that each fiber is
homeomorphic to a fractal blowup. We prove that there is a natural action of a
Renault-Deaconu groupoid on our fractafold bundle and that the resulting action
groupoid is a Renault-Deaconu groupoid itself. We also show that when the
bundle is locally compact the associated $C^*$-algebra is primitive and has a
densely defined lower-semicontinuous trace.


title: Functional Ito Calculus, Path-dependence and the Computation of Greeks

abstract:
  Dupire's functional It\^o calculus provides an alternative approach to the
classical Malliavin calculus for the computation of sensitivities, also called
Greeks, of path-dependent derivatives prices. In this paper, we introduce a
measure of path-dependence of functionals within the functional It\^o calculus
framework. Namely, we consider the Lie bracket of the space and time functional
derivatives, which we use to classify functionals accordingly to their degree
of path-dependence. We then revisit the problem of efficient numerical
computation of Greeks for path-dependent derivatives using integration by parts
techniques. Special attention is paid to path-dependent functionals with zero
Lie bracket, called locally weakly path-dependent functionals in our
classification. Hence, we derive the weighted-expectation formulas for their
Greeks. In the more general case of fully path-dependent functionals, we show
that, equipped with the functional It\^o calculus, we are able to analyze the
effect of the Lie bracket on the computation of Greeks. Moreover, we are also
able to consider the more general dynamics of path-dependent volatility. These
were not achieved using Malliavin calculus.


title: Sampling Content Distributed Over Graphs

abstract:
  Despite recent effort to estimate topology characteristics of large graphs
(i.e., online social networks and peer-to-peer networks), little attention has
been given to develop a formal methodology to characterize the vast amount of
content distributed over these networks. Due to the large scale nature of these
networks, exhaustive enumeration of this content is computationally
prohibitive. In this paper, we show how one can obtain content properties by
sampling only a small fraction of vertices. We first show that when sampling is
naively applied, this can produce a huge bias in content statistics (i.e.,
average number of content duplications). To remove this bias, one may use
maximum likelihood estimation to estimate content characteristics. However our
experimental results show that one needs to sample most vertices in the graph
to obtain accurate statistics using such a method. To address this challenge,
we propose two efficient estimators: special copy estimator (SCE) and weighted
copy estimator (WCE) to measure content characteristics using available
information in sampled contents. SCE uses the special content copy indicator to
compute the estimate, while WCE derives the estimate based on meta-information
in sampled vertices. We perform experiments to show WCE and SCE are cost
effective and also ``{\em asymptotically unbiased}''. Our methodology provides
a new tool for researchers to efficiently query content distributed in large
scale networks.


title: SU(3)F in nonleptonic charm decays

abstract:
  We present updated results of an SU(3)-flavor analysis of D->P P decay data
including linear breaking and no further assumptions. The global fit is
consistent with nominal (~ 30%) SU(3)F breaking and returns enhanced penguin
(triplet) contributions. Their size is driven, in addition to Delta A_{CP}, by
the CP asymmetries of D_0->K_S K_S, D_s->K_S pi^+ and D_s->K^+ pi^0 decays. It
is therefore especially important to improve these measurements.


title: Pattern Transitions in Unstable Viscous Convective Medium

abstract:
  Convection in a thin layer of liquid (gas) with temperature dependent
viscosity between poorly heat conducting boundaries is studied within framework
of the Proctor-Sivashinsky model. This model is examined in order to study both
the flow pattern formation and the second-order structural phase transitions as
between patterns with translational invariance as well as between structures
with broken translational invariance but keeping a long-range order. The
spatial spectrum of arising patterns and estimation of their visual
defectiveness are analyzed. The relation between the density of pattern defects
and spectral characteristics of the pattern is found. We also discuss the noise
effects on the formation of pattern defects. The influence of temperature
dependence of viscosity on the process of pattern formation and structure
transformations is also discussed. It is shown that the temperature dependence
of viscosity inhibits structural transition from regular rolls to square cells.


title:
Leading-order hadronic contribution to the anomalous magnetic moment of
  the muon from N_f=2+1+1 twisted mass fermions

abstract:
  We present results for the leading order QCD correction to the anomalous
magnetic moment of the muon including the first two generations of quarks as
dynamical degrees of freedom. Several light quark masses are examined in order
to yield a controlled extrapolation to the physical pion mass. We analyse
ensembles for three different lattice spacings and several volumes in order to
investigate lattice artefacts and finite-size effects, respectively. We also
provide preliminary results for this quantity for two flavours of
mass-degenerate quarks at the physical value of the pion mass.


title:
Pressure Distribution and Critical Exponent in Statically Jammed and
  Shear-Driven Frictionless Disks

abstract:
  We numerically study the distributions of global pressure that are found in
ensembles of statically jammed and quasistatically sheared systems of
bidisperse, frictionless, disks at fixed packing fraction $\phi$ in two
dimensions. We use these distributions to address the question of how pressure
increases as $\phi$ increases above the jamming point $\phi_J$, $p\sim |\phi -
\phi_J|^y$. For statically jammed ensembles, our results are consistent with
the exponent $y$ being simply related to the power law of the interparticle
soft-core interaction. For sheared systems, however, the value of $y$ is
consistent with a non-trivial value, as found previously in rheological
simulations.


title:
Relating different quantum generalizations of the conditional Renyi
  entropy

abstract:
  Recently a new quantum generalization of the Renyi divergence and the
corresponding conditional Renyi entropies was proposed. Here we report on a
surprising relation between conditional Renyi entropies based on this new
generalization and conditional Renyi entropies based on the quantum relative
Renyi entropy that was used in previous literature. Our result generalizes the
well-known duality relation H(A|B) + H(A|C) = 0 of the conditional von Neumann
entropy for tripartite pure states to Renyi entropies of two different kinds.
  As a direct application, we prove a collection of inequalities that relate
different conditional Renyi entropies and derive a new entropic uncertainty
relation.


title: Spline approximations to conditional Archimedean copula

abstract:
  We propose a flexible copula model to describe changes with a covariate in
the dependence structure of (conditionally exchangeable) random variables. The
starting point is a spline approximation to the generator of an Archimedean
copula. Changes in the dependence structure with a covariate $x$ are modelled
by flexible regression of the spline coefficients on $x$. The performances and
properties of the spline estimate of the reference generator and the abilities
of these conditional models to approximate conditional copulas are studied
through simulations. Inference is made using Bayesian arguments with posterior
distributions explored using importance sampling or adaptive MCMC algorithms.
The modelling strategy is illustrated with two examples.


title: The thermodynamic and the continuum limit of meson screening masses

abstract:
  We present results on the thermodynamic and continuum limit of meson
screening masses in the deconfined phase, using standard staggered and
non-perturbatively clover-improved Wilson fermions in the quenched
approximation with light quark masses.
  For two temperatures, 1.5 Tc and 3.0 Tc, it is found that on finite lattices
screening masses differ between the actions. We study if both actions reproduce
the same masses in the continuum by employing different methods of
extrapolation to the thermodynamic and continuum limit.


title:
Probing the Statistical Validity of the Ductile-to-Brittle Transition in
  Metallic Nanowires Using GPU Computing

abstract:
  We perform a large-scale statistical analysis (> 2000 independent
simulations) of the elongation and rupture of gold nanowires, probing the
validity and scope of the recently proposed ductile-to-brittle transition that
occurs with increasing nanowire length [Wu et. al., Nano Lett., 12, 910-914
(2012)]. To facilitate a high-throughput simulation approach, we implement the
second-moment approximation to the tight-binding (TB-SMA) potential within
HOOMD-Blue, a molecular dynamics package which runs on massively parallel
graphics processing units (GPUs). In a statistical sense, we find that the
nanowires obey the ductile-to-brittle model quite well; however, we observe
several unexpected features from the simulations that build on our
understanding of the ductile-to-brittle transition. First, occasional failure
behavior is observed that qualitatively differs from that predicted by the
model prediction; this is attributed to stochastic thermal motion of the Au
atoms and occurs at temperatures as low as 10 K. In addition, we also find that
the ductile-to-brittle model, which was developed using classical dislocation
theory, holds for nanowires as small as 3 nm in diameter. Finally, we
demonstrate that the nanowire critical length is higher at 298 K relative to 10
K, a result that is not predicted by the ductile-to-brittle model. These
results offer practical design strategies for adjusting nanowire failure and
structure, and also demonstrate that GPU computing is an excellent tool for
studies requiring a large number independent trajectories in order to fully
characterize a system's behavior.


title:
Bulk Viscosity of dual Fluid at Finite Cutoff Surface via Gravity/Fluid
  correspondence in Einstein-Maxwell Gravity

abstract:
  Based on the previous paper arXiv:1207.5309, we investigate the possibility
to find out the bulk viscosity of dual fluid at the finite cutoff surface via
gravity/fluid correspondence in Einstein-Maxwell gravity. We find that if we
adopt new conditions to fix the undetermined parameters contained in the stress
tensor and charged current of the dual fluid, two new terms appear in the
stress tensor of the dual fluid. One new term is related to the bulk viscosity
term, while the other can be related to the perturbation of energy density. In
addition, since the parameters contained in the charged current are the same,
the charged current is not changed.


title: Route to observing topological edge modes in ultracold fermions

abstract:
  We show how to exploit the rich hyperfine structure of fermionic alkali atoms
to produce a quasi-1D topological superfluid while avoiding excessive heating
from off-resonant scattering. We model interacting fermions where four
hyperfine states are coupled by a variety of optical and microwave fields. We
calculate the local density of states in a trap, finding regimes with zero
energy topological edge modes. Heating rates in this system are significantly
suppressed compared to simple Raman-induced spin-orbit coupling approaches.


title: Performance of the LHCb Outer Tracker

abstract:
  The LHCb Outer Tracker is a gaseous detector covering an area of 5x6 m2 with
12 double layers of straw tubes. The detector with its services are described
together with the commissioning and calibration procedures. Based on data of
the first LHC running period from 2010 to 2012, the performance of the readout
electronics and the single hit resolution and efficiency are presented. The
efficiency to detect a hit in the central half of the straw is estimated to be
99.2%, and the position resolution is determined to be approximately 200 um.
The Outer Tracker received a dose in the hottest region corresponding to 0.12
C/cm, and no signs of gain deterioration or other ageing effects are observed.


title:
CHANG-ES III: UGC10288 -- An Edge-on Galaxy with a Background
  Double-lobed Radio Source

abstract:
  This 3rd paper in the CHANG-ES series shows the first results from our
regular data taken with the Karl G. Jansky Very Large Array (JVLA). The edge-on
galaxy, UGC 10288, has been observed in the B, C, and D configurations at
L-band (1.5 GHz) and in the C and D configurations at C-band (6 GHz) in all
polarization products. We show the first spatially resolved images in these
bands,the first polarization images, and the first composed image at an
intermediate frequency (4.1 GHz) which has been formed from a combination of
all data sets.
  A surprising new result is the presence of a strong, polarized, double-lobed
extragalactic radio source ({\it CHANG-ES A}) almost immediately behind the
galaxy and perpendicular to its disk. The core of {\it CHANG-ES A} has an
optical counterpart at a photometric redshift of $z_{phot}\,=\,0.39$; the
southern radio lobe is behind the disk of UGC 10288 and the northern lobe is
behind the halo region. This background `probe' has allowed us to do a
preliminary Faraday Rotation analysis of the foreground galaxy, putting limits
on the regular magnetic field and electron density in the halo of UGC 10288 in
regions in which there is no direct detection of a radio continuum halo.
  We have revised the flux densities of the two sources individually as well as
the star formation rate (SFR) for UGC 10288. UGC 10288 would have fallen well
below the CHANG-ES flux density cutoff, had it been considered without the
brighter contribution of the background source.
  UGC 10288 shows discrete high-latitude radio continuum features, but it does
not have a {\it global} radio continuum halo. The total minimum magnetic field
strength at a sample position in the arc is $\sim$ 10 $\mu$G. Thus, this galaxy
still appears to be able to form substantial high latitude, localized features
in spite of its relatively low SFR.


title: Inverse problems in multifractal analysis

abstract:
  Multifractal formalism is designed to describe the distribution at small
scales of the elements of $\mathcal M^+_c(\R^d)$, the set of positive, finite
and compactly supported Borel measures on $\R^d$. It is valid for such a
measure $\mu$ when its Hausdorff spectrum is the upper semi-continuous function
given by the concave Legendre-Fenchel transform of the free energy function
$\tau_\mu$ associated with $\mu$; this is the case for fundamental classes of
exact dimensional measures.
  For any function $\tau$ candidate to be the free energy function of some
$\mu\in \mathcal M^+_c(\R^d)$, we build such a measure, exact dimensional, and
obeying the multifractal formalism. This result is extended to a refined
formalism considering jointly Hausdorff and packing spectra. Also, for any
upper semi-continuous function candidate to be the lower Hausdorff spectrum of
some exact dimensional $\mu\in\mathcal M^+_c(\R^d)$, we build such a measure.
  Our results transfer to the analoguous inverse problems in multifractal
analysis of H\"older continuous functions.


title: Rates of convergence towards the Fr\'echet distribution

abstract:
  We develop Stein's method for the Fr\'echet distribution and apply it to
compute rates of convergence in distribution of renormalized sample maxima to
the Fr\'echet distribution.


title: Connectivity of soft random geometric graphs

abstract:
  Consider a graph on $n$ uniform random points in the unit square, each pair
being connected by an edge with probability $p$ if the inter-point distance is
at most $r$. We show that as $n\to\infty$ the probability of full connectivity
is governed by that of having no isolated vertices, itself governed by a
Poisson approximation for the number of isolated vertices, uniformly over all
choices of $p,r$. We determine the asymptotic probability of connectivity for
all $(p_n,r_n)$ subject to $r_n=O(n^{-\varepsilon})$, some $\varepsilon >0$. We
generalize the first result to higher dimensions and to a larger class of
connection probability functions.


title: Queuing Networks with Varying Topology -- A Mean-Field Approach

abstract:
  We consider the queuing networks, which are made from servers, exchanging
their positions. The customers, using the network, try to reach their
destinations, which is complicated by the movements of the servers, taking
their customers with them, while they wait for the service. We develop the
general theory of such networks, and we establish the convergence of the
symmetrized version of the network to the Non-Linear Markov Process.


title: Deciding first-order properties of nowhere dense graphs

abstract:
  Nowhere dense graph classes, introduced by Nesetril and Ossona de Mendez,
form a large variety of classes of "sparse graphs" including the class of
planar graphs, actually all classes with excluded minors, and also bounded
degree graphs and graph classes of bounded expansion.
  We show that deciding properties of graphs definable in first-order logic is
fixed-parameter tractable on nowhere dense graph classes. At least for graph
classes closed under taking subgraphs, this result is optimal: it was known
before that for all classes C of graphs closed under taking subgraphs, if
deciding first-order properties of graphs in C is fixed-parameter tractable,
then C must be nowhere dense (under a reasonable complexity theoretic
assumption).
  As a by-product, we give an algorithmic construction of sparse neighbourhood
covers for nowhere dense graphs. This extends and improves previous
constructions of neighbourhood covers for graph classes with excluded minors.
At the same time, our construction is considerably simpler than those. Our
proofs are based on a new game-theoretic characterisation of nowhere dense
graphs that allows for a recursive version of locality-based algorithms on
these classes. On the logical side, we prove a "rank-preserving" version of
Gaifman's locality theorem.


title:
The Stabilizing Role of Global Alliances in the Dynamics of Coalition
  Forming

abstract:
  Coalition forming is investigated among countries, which are coupled with
short range interactions, under the influence of external fields produced by
the existence of global alliances. The model rests on the natural model of
coalition forming inspired from Statistical Physics, where instabilities are a
consequence of decentralized maximization of the individual benefits of actors
within their long horizon of rationality as the ability to envision a way
through intermediate loosing states, to a better configuration. The effects of
those external incentives on the interactions between countries and the
eventual stabilization of coalitions are studied. The results shed a new light
on the understanding of the complex phenomena of stabilization and
fragmentation in the coalition dynamics and on the possibility to design stable
coalitions. In addition to the formal implementation of the model, the
phenomena is illustrated through some historical cases of conflicts in Western
Europe.


title:
Phase-dependent spectral control of pulsed modulation instability via
  dichromatic seed fields

abstract:
  We investigated experimentally and numerically the spectral control of
modulation instability (MI) dynamics via the initial phase relation of two weak
seed fields. Specifically, we show how second-order modulation instability
dynamics exhibit phase-dependent anti-correlated growth rates of adjacent
spectral sidebands. This effect enables a novel method to control MI-based
frequency conversion: in contrast to first-order MI dynamics, which exhibit a
uniform phase dependence of the growth rates, second-order MI dynamics allow to
redistribute the spectral energy, leading to an asymmetric spectrum. Therefore,
the presented findings should be very attractive to different applications,
such as phase-sensitive amplification or supercontinuum generation initiated by
MI.


title:
Modeling magnetized star-planet interactions: boundary conditions
  effects

abstract:
  We model the magnetized interaction between a star and a close-in planet
(SPMIs), using global, magnetohydrodynamic numerical simulations. In this
proceedings, we study the effects of the numerical boundary conditions at the
stellar surface, where the stellar wind is driven, and in the planetary
interior. We show that is it possible to design boundary conditions that are
adequate to obtain physically realistic, steady-state solutions for cases with
both magnetized and unmagnetized planets. This encourages further development
of numerical studies, in order to better constrain and understand SPMIs, as
well as their effects on the star-planet rotational evolution.


title: A Categorical Theory of Patches

abstract:
  When working with distant collaborators on the same documents, one often uses
a version control system, which is a program tracking the history of files and
helping importing modifications brought by others as patches. The
implementation of such a system requires to handle lots of situations depending
on the operations performed by users on files, and it is thus difficult to
ensure that all the corner cases have been correctly addressed. Here, instead
of verifying the implementation of such a system, we adopt a complementary
approach: we introduce a theoretical model, which is defined abstractly by the
universal property that it should satisfy, and work out a concrete description
of it. We begin by defining a category of files and patches, where the
operation of merging the effect of two coinitial patches is defined by pushout.
Since two patches can be incompatible, such a pushout does not necessarily
exist in the category, which raises the question of which is the correct
category to represent and manipulate files in conflicting state. We provide an
answer by investigating the free completion of the category of files under
finite colimits, and give an explicit description of this category: its objects
are finite sets labeled by lines equipped with a transitive relation and
morphisms are partial functions respecting labeling and relations.


title: On graded polynomial identities of $sl_{2}(F)$ over a finite field

abstract:
  Let $F$ be a finite field of $char F > 3$ and $sl_{2}(F)$ be the Lie algebra
of traceless $2\times 2$ matrices over $F$. This paper aims for the following
goals:
  Find a basis for the $\mathbb{Z}_{2}$-graded identities of $sl_{2}(F)$;
  Find a basis for the $\mathbb{Z}_{3}$-graded identities of $sl_{2}(F)$ when
$F$ contains a primitive 3rd root of one;
  Find a basis for the $\mathbb{Z}_{2}\times \mathbb{Z}_{2}$-graded identities
of $sl_{2}(F)$.


title: Physics Items and Student's Performance at Enem

abstract:
  The Brazilian National Assessment of Secondary Education (ENEM, Exame
Nacional do Ensino M\'edio) has changed in 2009: from a self-assessment of
competences at the end of high school to an assessment that allows access to
college and student financing. From a single general exam, now there are tests
in four areas: Mathematics, Language, Natural Sciences and Social Sciences. A
new Reference Matrix is build with components as cognitive domains,
competencies, skills and knowledge objects; also, the methodological framework
has changed, using now Item Response Theory to provide scores and allowing
longitudinal comparison of results from different years, providing conditions
for monitoring high school quality in Brazil. We present a study on the issues
discussed in Natural Science Test of ENEM over the years 2009, 2010 and 2011.
Qualitative variables are proposed to characterize the items, and data from
students' responses in Physics items were analysed. The qualitative analysis
reveals the characteristics of the exam in these years: long items, only a few
of them demanding more complex reasoning, a characteristic of problem solving
skills. The analysis of student performance also reveals that learning physics
is not attained, with a percentage of correct answers on items that is almost
always small, and that items that require some type of disciplinary knowledge
or require use of mathematical reasoning presents a performance significantly
weaker.


title: Finite primitive permutation groups and regular cycles of their elements

abstract:
  We conjecture that if $G$ is a finite primitive group and if $g$ is an
element of $G$, then either the element $g$ has a cycle of length equal to its
order, or for some $r,m$ and $k$, the group $G\leq S_m\wr S_r$, preserving a
product structure of $r$ direct copies of the natural action of $S_m$ or $A_m$
on $k$-sets. In this paper we reduce this conjecture to the case that $G$ is an
almost simple group with socle a classical group.


title: Endomorphisms of quantum generalized Weyl algebras

abstract:
  We prove that every endomorphism of a simple quantum generalized Weyl algebra
$A$ over a commutative Laurent polynomial ring in one variable is an
automorphism. This is achieved by obtaining an explicit classification of all
endomorphisms of $A$. Our main result applies to minimal primitive factors of
the quantized enveloping algebra of $U_q(\mathfrak{sl}_2)$ and certain minimal
primitive quotients of the positive part of $U_q(\mathfrak{so}_5)$.


title: A characterization theorem for matrix variances

abstract:
  Some recent papers formulated sufficient conditions for the decomposition of
matrix variances. A statement was that if we have one or two observables, then
the decomposition is possible. In this paper we consider an arbitrary finite
set of observables and we present a necessary and sufficient condition for the
decomposition of the matrix variances.


title: Higher Order Theories and its Relationship with Noncommutativity

abstract:
  We present a relationship between noncommutativity and higher order time
derivative theories using a method perturbative. We introduce a generalization
of the Chern-Simons Quantum Mechanics for higher order time derivatives. This
model presents noncommutativity in a natural way when we project to states of
low energy. Compared with the usual model, our system presents noncommutativity
without the necessity of taking the limit of strong field. We quantized the
theory using a Bopp's shift of the noncommutative variables and we obtain an
spectrum without negatives energies. In addition we extend the model to high
order derivatives and noncommutativity with variable dependent parameter.


title:
Equation of state in the generalized density scaling regime studied from
  ambient to ultra-high pressure conditions

abstract:
  In this paper, based on the effective intermolecular potential with well
separated density and configuration contributions and the definition of the
isothermal bulk modulus, we derive two similar equations of state dedicated to
describe volumetric data of supercooled liquids studied in the extremely wide
pressure range related to the extremely wide density range. Both the equations
comply with the generalized density scaling law of molecular dynamics versus
$h(\rho ) / T$ at different densities $\rho $ and temperatures $T$, where the
scaling exponent can be in general only a density function $\gamma(\rho ) =
\it{d} \rm{ln} \it{h / d} \rm{ln}\rho $ as recently argued by the theory of
isomorphs. We successfully verify these equations of state by using data
obtained from molecular dynamics simulations of the Kob-Andersen binary
Lennard-Jones liquid. As a very important result, we find that the
one-parameter density function $h(\rho )$ analytically formulated in the case
of this prototypical model of supercooled liquid, which implies the
one-parameter density function $\gamma(\rho )$, is able to scale the structural
relaxation times with the value of this function parameter determined by
fitting the volumetric simulation data to the equations of state. We also show
that these equations of state properly describe the pressure dependences of the
isothermal bulk modulus and the configurational isothermal bulk modulus in the
extremely wide pressure range investigated by the computer simulations.
Moreover, we discuss the possible forms of the density functions $h(\rho )$ and
$\gamma(\rho )$ for real glass formers, which are suggested to be different
from those valid for the model of supercooled liquid based on the Lennard-Jones
intermolecular potential.


title: Distributed SUSY Breaking: Dark Energy, Newton's Law and the LHC

abstract:
  We identify the underlying symmetry mechanism that suppresses the low-energy
effective 4D cosmological constant within 6D supergravity models, leading to
results suppressed by powers of the KK scale relative to the much larger masses
associated with particles localized on codimension-2 branes. In these models
the conditions for unbroken supersymmetry can be satisfied locally everywhere
within the extra dimensions, but are obstructed by global conditions like flux
quantization or the mutual inconsistency of boundary conditions at the various
branes. Consequently quantities forbidden by supersymmetry cannot be nonzero
until wavelengths of order the KK scale are integrated out, since only such
long wavelength modes see the entire space and so know that supersymmetry
breaks. We verify these arguments by extending earlier rugby-ball calculations
of one-loop vacuum energies to more general pairs of branes within two warped
extra dimensions. The predicted effective 4D vacuum energy density can be of
order C (m Mg/4 pi Mp)^4, where Mg (Mp) is the rationalized 6D (4D) Planck
scale and m is the heaviest brane-localized particle. Numerically this is C
(5.6 x 10^{-5} eV)^4 if we take m = 173 GeV and take Mg as small as possible
(10 TeV corresponding to KK size r < 1 micron), consistent with supernova
bounds. C is a constant depending on details of the bulk spectrum, which could
be ~ 500 for each of hundreds of fields. The value C ~ 6 x 10^6 gives the
observed Dark Energy density.


title: A covariant causal set approach to discrete quantum gravity

abstract:
  A covariant causal set (c-causet) is a causal set that is invariant under
labeling. Such causets are well-behaved and have a rigid geometry that is
determined by a sequence of positive integers called the shell sequence. We
first consider the microscopic picture. In this picture, the vertices of a
c-causet have integer labels that are unique up to a label isomorphism. This
labeling enables us to define a natural metric $d(a,b)$ between time-like
separated vertices $a$ and $b$. The time metric $d(a,b)$ results in a natural
definition of a geodesic from $a$ to $b$. It turns out that there can be $n\ge
1$ such geodesics. Letting $a$ be the origin (the big bang), we define the
curvature $K(b)$ of $b$ to be $n-1$. Assuming that particles tend to move along
geodesics, $K(b)$ gives the tendency that vertex $b$ is occupied. In this way,
the mass distribution is determined by the geometry of the c-causet. We next
consider the macroscopic picture which describes the growth process of
c-causets. We propose that this process is governed by a quantum dynamics given
by complex amplitudes. At present, these amplitudes are unknown. But if they
can be found, they will determine the (approximate) geometry of the c-causet
describing our particular universe. As an illustration, we present a simple
example of an amplitude process that may have physical relevance. We also give
a discrete analogue of Einstein's field equations.


title: Polytope Expansion of Lie Characters and Applications

abstract:
  The weight systems of finite-dimensional representations of complex, simple
Lie algebras exhibit patterns beyond Weyl-group symmetry. These patterns occur
because weight systems can be decomposed into lattice polytopes in a natural
way. Since lattice polytopes are relatively simple, this decomposition is
useful, in addition to being more economical than the decomposition into single
weights. An expansion of characters into polytope sums follows from the
polytope decomposition of weight systems. We study this polytope expansion
here. A new, general formula is given for the polytope sums involved. The
combinatorics of the polytope expansion are analyzed; we point out that they
are reduced from those of the Weyl character formula (described by the Kostant
partition function) in an optimal way. We also show that the weight
multiplicities can be found easily from the polytope multiplicities, indicating
explicitly the equivalence of the two descriptions. Finally, we demonstrate the
utility of the polytope expansion by showing how polytope multiplicities can be
used in the calculation of tensor product decompositions, and subalgebra
branching rules.


title: Strong approximation and descent

abstract:
  We introduce descent methods to the study of strong approximation on
algebraic varieties. We apply them to two classes of varieties defined by
P(t)=N_{K/k}(z): firstly for quartic extensions of number fields K/k and
quadratic polynomials P(t) in one variable, and secondly for k=Q, an arbitrary
number field K and P(t) a product of linear polynomials over Q in at least two
variables. Finally, we illustrate that a certain unboundedness condition at
archimedean places is necessary for strong approximation.


title: Correcting Correlation Function Measurements

abstract:
  Correlation functions measured as a function of $\Delta \eta, \Delta \phi$
have emerged as a powerful tool to study the dynamics of particle production in
nuclear collisions at high energy. They are however subject, like any other
observables, to instrumental effects which must be properly accounted for to
extract meaningful physics results. We compare the merits of several techniques
used towards measurement of these correlation functions in nuclear collisions.
We discuss and distinguish the effects of finite acceptance, and detection
efficiency that may vary with collision parameters such as the position of the
event in the detector and the instantaneous luminosity of the beam. We focus in
particular on instrumental effects which break the factorization of the
particle pair detection efficiency, and describe a technique to recover the
robustness of correlation observables. We finally introduce a multi-dimensional
weight method to correct for efficiencies that vary simultaneously with
particle pseudo rapidity, azimuthal angle, transverse momentum, and the
collision vertex position. The method can be generalized to account for any
number of "event variables" that may break the factorability of the pair
efficiency.


title: Survivability of dust in tokamaks: dust transport in the divertor sheath

abstract:
  The survivability of dust being transported in the magnetized sheath near the
divertor plate of a tokamak and its impact on the desired balance of erosion
and redeposition for a steady-state reactor are investigated. Two different
divertor scenarios are considered. The first is characterized by an energy flux
perpendicular to the plate $q_0\simeq 1$ MW/m$^2$ typical of current
short-pulse tokamaks. The second has $q_0\simeq 10$ MW/m$^2$ and is relevant to
long-pulse machines like ITER or DEMO.
  It is shown that micrometer dust particles can survive rather easily near the
plates of a divertor plasma with $q_0\simeq 1$ MW/m$^2$ because thermal
radiation provides adequate cooling for the dust particle. On the other hand,
the survivability of micrometer dust particles near the divertor plates is
drastically reduced when $q_0\simeq 10$ MW/m$^2$. Micrometer dust particles
redeposit their material non-locally, leading to a net poloidal mass migration
across the divertor. Smaller particles (with radius $\sim 0.1$ $\mu$m) cannot
survive near the divertor and redeposit their material locally. Bigger particle
(with radius $\sim 10$ $\mu$m) can instead survive partially and move outside
the divertor strike points, thus causing a net loss of divertor material to
dust accumulation inside the chamber and some non-local redeposition. The
implications of these results for ITER are discussed.


title:
Preliminary study for the measurement of the Lense-Thirring effect with
  the Galileo satellites

abstract:
  The precession of the orbital node of a particle orbiting a rotating mass is
known as Lense-Thirring effect (LTE) and is a manifestation of the general
relativistic phenomenon of dragging of inertial frames or frame-dragging. The
LTE has already been measured by using the node drifts of the LAGEOS satellites
and GRACE-based Earth gravity field models with an accuracy of about 10% and
will be improved down to a few percent with the recent LARES experiment. The
Galileo system will provide 27 new node observables for the LTE estimation and
their combination with the LAGEOS and LARES satellites can potentially reduce
even more the error due to the mismodeling in Earth's gravity field. However,
the accurate determination of the Galileo orbits requires the estimation of
many different parameters, which can absorb the LTE on the orbital nodes.
Moreover, the accuracy of the Galileo orbits and hence, of their node drifts,
is mainly limited by the mismodeling in the Solar Radiation Pressure (SRP).
Using simulated data we analyze the effects of the mismodeling in the SRP on
the Galileo nodes and propose optimal orbit parameterizations for the
measurement of the LTE from the future Galileo observations.


title: Sum Secrecy Rate in Full-Duplex Wiretap Channel with Imperfect CSI

abstract:
  In this paper, we consider the achievable sum secrecy rate in full-duplex
wiretap channel in the presence of an eavesdropper and imperfect channel state
information (CSI). We assume that the users participating in full-duplex
communication and the eavesdropper have single antenna each. The users have
individual transmit power constraints. They also transmit jamming signals to
improve the secrecy rates. We obtain the achievable perfect secrecy rate region
by maximizing the sum secrecy rate. We also obtain the corresponding optimum
powers of the message signals and the jamming signals. Numerical results that
show the impact of imperfect CSI on the achievable secrecy rate region are
presented.


title: The Landau--Zener Problem with Decay and with Dephasing

abstract:
  Two aspects of the classic two-level Landau--Zener (LZ) problem are
considered. First, we address the LZ problem when one or both levels decay,
i.e., $\veps_j(t) \to \veps_j(t)-i \Gamma_j/2$. We find that if the system
evolves from an initial time $-T$ to a final time $+T$ such that $|\veps_1(\pm
T)-\veps_2(\pm T)|$ is not too large, the LZ survival probability of a state $|
j \ra$ can {\em increase} with increasing decay rate of the other state $|i \ne
j \ra$. This surprising result occurs because the decay results in crossing of
the two eigenvalues of the instantaneous non-Hermitian Hamiltonian. On the
other hand, if $|\veps_1(\pm T)-\veps_2(\pm T)| \to \infty$ as $T \to \infty$,
the probability is {\em independent} of the decay rate. These results are based
on analytic solutions of the time-dependent Schr\"odinger equations for two
cases: (a) the energy levels depend linearly on time, and (b) the energy levels
are bounded and of the form $\veps_{1,2}(t) = \pm \veps \tanh (t/{\cal T})$.
Second, we study LZ transitions affected by dephasing by formulating the
Landau--Zener problem with noise in terms of a Schr\"{o}dinger-Langevin
stochastic coupled set of differential equations. The LZ survival probability
then becomes a random variable whose probability distribution is shown to
behave very differently for long and short dephasing times. We also discuss the
combined effects of decay and dephasing on the LZ probability.


title:
High-harmonic probing of electronic coherence in dynamically aligned
  molecules

abstract:
  We introduce and demonstrate a new approach to measuring coherent electron
wave packets using high-harmonic spectroscopy. By preparing a molecule in a
coherent superposition of electronic states, we show that electronic coherence
opens previously unobserved high-harmonic-generation channels that connect
distinct but coherently related electronic states. Performing the measurements
in dynamically aligned nitric oxide (NO) molecules we observe the complex
temporal evolution of the electronic coherence under coupling to nuclear
motion. Choosing a weakly allowed transition to prepare the wave packet, we
demonstrate an unprecedented sensitivity that arises from optical interference
between coherent and incoherent pathways. This mechanism converts a 0.1 $%$
excitation fraction into a $\sim$20 $%$ signal modulation.


title: On extended sign-changeable interactions in the dark sector

abstract:
  We extend the cosmological couplings proposed in Sun et al. and Wei, where
they suggested interactions with change of signs along the cosmological
evolution. Our extension liberates the changes of sign of the interaction from
the deceleration parameter and from the relation of energy densities of the
dark sector and considers the presence of non interactive matter. In three
cases we obtain the general solutions and the results obtained in models fitted
with Hubble's function and SNe Ia data, are analyzed regarding the problem of
the cosmological coincidence, the problem of the crisis of the cosmological age
and the magnitude of the energy density of dark energy at early universe. Also
we graphically study the range of variation of, the actual dark matter density
parameter, the effective equation of state of the dark energy and the redshift
of transition to the accelerated regimen, generated by variations at order
$1\sigma$ in the coupling parameters.


title: Counting smaller elements in the Tamari and m-Tamari lattices

abstract:
  We introduce new combinatorial objects, the interval- posets, that encode
intervals of the Tamari lattice. We then find a combinatorial interpretation of
the bilinear operator that appears in the functional equation of Tamari
intervals described by Chapoton. Thus, we retrieve this functional equation and
prove that the polynomial recursively computed from the bilinear operator on
each tree T counts the number of trees smaller than T in the Tamari order. Then
we show that a similar m + 1-linear operator is also used in the functionnal
equation of m-Tamari intervals. We explain how the m-Tamari lattices can be
interpreted in terms of m+1-ary trees or a certain class of binary trees. We
then use the interval-posets to recover the functional equation of m-Tamari
intervals and to prove a generalized formula that counts the number of elements
smaller than or equal to a given tree in the m-Tamari lattice.


title:
Two-pulse field-free orientation reveals anisotropy of molecular shape
  resonance

abstract:
  We report the observation of macroscopic field-free orientation, i.e. more
than 73 % of CO molecules pointing in the same direction. This is achieved
through an all-optical scheme operating at high particle densities
($>10^{17}$cm$^{-3}$) that combines a one-color ($\omega$) and a two-color
($\omega + 2\omega$) non-resonant femtosecond laser pulses. We show that the
achieved orientation solely relies on the hyperpolarizability interaction as
opposed to an ionization-depletion mechanism thus opening a wide range of
applications. The achieved strong orientation enables us to reveal the
molecular-frame anisotropies of the photorecombination amplitudes and phases
caused by a shape resonance. The resonance appears as a local maximum in the
even-harmonic emission around 28~eV. In contrast, the odd-harmonic emission is
suppressed in this spectral region through the combined effects of an
asymmetric photorecombination phase and a sub-cycle Stark effect, generic for
polar molecules, that we experimentally identify.


title:
Measurements of t t-bar spin correlations and top-quark polarization
  using dilepton final states in pp collisions at sqrt(s) = 7 TeV

abstract:
  Spin correlations in the top quark-antiquark system and the polarization of
the top quark are measured using dilepton final states produced in pp
collisions at the LHC at sqrt(s) = 7 TeV. The data correspond to an integrated
luminosity of 5.0 inverse femtobarns collected with the CMS detector. The
measurements are performed using events with two oppositely charged leptons
(electrons or muons), a significant imbalance in transverse momentum, and two
or more jets, where at least one of the jets is identified as originating from
a b quark. The spin correlations and polarization are measured through
asymmetries in angular distributions of the two selected leptons, unfolded to
the parton level. All measurements are found to be in agreement with
predictions of the standard model.


title:
On point-like interaction of three particles: two fermions and another
  particle. II

abstract:
  This work continues \cite{bib1} where the construction of Hamiltonian $H$ for
the system of three quantum particles is considered. Namely the system consists
of two fermions with mass $1$ and another particle with mass $m>0$. In the
present paper, like in \cite{bib1}, we study the part $T_{l=1}$ of auxilliary
operator $T = \oplus_{l=0}^{\infty} T_l$ involving the construction of the
resolvent for the operator $H$. In this work together with the previous one two
constants $0<m_1<m_0<\infty$ were found such that: 1) for $m>m_0$ the operator
$T_{l=1}$ is selfadjoint but for $m \leqslant m_0$ it has the deficiency
indexes $(1,1)$; 2) for $m_1<m<m_0$ any selfadjoint extension of $T_{l=1}$ is
semibounded below; 3) for $0<m<m_1$ any selfadjoint extension of $T_{l=1}$ has
the sequence of eigenvalues $\{\lambda_n <0, n> n_0\}$ with the asymptotics \[
\lambda_n = \lambda_0 e^{\delta n} + O(1),\quad n\to\infty, \] where $\lambda_0
<0$, $\delta >0$, $n_0>0$ and there is'nt other spectrum on the interval
$\lambda < \lambda_{n_0}$.


title: Weak lensing using only galaxy position angles

abstract:
  We develop a method for performing a weak lensing analysis using only
measurements of galaxy position angles. By analysing the statistical properties
of the galaxy orientations given a known intrinsic ellipticity distribution, we
show that it is possible to obtain estimates of the shear by minimizing a
$\chi^2$ statistic. The method is demonstrated using simulations where the
components of the intrinsic ellipticity are taken to be Gaussian distributed.
Uncertainties in the position angle measurements introduce a bias into the
shear estimates which can be reduced to negligible levels by introducing a
correction term into the formalism. We generalize our approach by developing an
algorithm to obtain direct shear estimators given any azimuthally symmetric
intrinsic ellipticity distribution. We introduce a method of measuring the
position angles of the galaxies from noisy pixelized images, and propose a
method to correct for biases which arise due to pixelization and correlations
between measurement errors and galaxy ellipticities. We also develop a method
to constrain the sample of galaxies used to obtain an estimate of the intrinsic
ellipticity distribution such that fractional biases in the resulting shear
estimates are below a given threshold value. We demonstrate the angle only
method by applying it to simulations where the ellipticities are taken to
follow a log-normal distribution. We compare the performance of the position
angle only method with the standard method based on full ellipticity
measurements by reconstructing lensing convergence maps from both numerical
simulations and from the CFHTLenS data. We find that the difference between the
convergence maps reconstructed using the two methods is consistent with noise.


title: On differential characteristic classes

abstract:
  In this paper we give explicit formulas of differential characteristic
classes of principal $G$-bundles with connections and prove their expected
properties. In particular, we obtain explicit formulas for differential Chern
classes, differential Pontryagin classes and differential Euler class.
Furthermore, we show that the differential Chern class is the unique natural
transformation from (Simons-Sullivan) differential $K$-theory to
(Cheeger-Simons) differential characters that is compatible with curvature and
characteristic class. We also give the explicit formula for the differential
Chern class on Freed-Lott differential $K$-theory. Finally we discuss the odd
differential Chern classes.


title: HS06 Benchmark for an ARM Server

abstract:
  We benchmarked an ARM cortex-A9 based server system with a four-core CPU
running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the
HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on
the system. The benchmark was run for various settings of the relevant gcc
compiler options. We did not find significant influence from the compiler
options on the benchmark result. The final HS06 benchmark result is 10.4.


title: Structure Trees and Networks

abstract:
  In this paper it is shown that for any network there is a uniquely determined
network based on a structure tree that provides a convenient way of determining
a minimal cut separating a pair $s, t$ where each of $s, t$ is either a vertex
or an end in the original network. A Max-Flow Min-Cut Theorem is proved for any
network. In the case of a Cayley Graph for a finitely generated group the
theory provides another proof of Stallings' Theorem on the structure of groups
with more than one end.


title: An adaptive finite element method for the infinity Laplacian

abstract:
  We construct a finite element method (FEM) for the infinity Laplacian.
Solutions of this problem may be singular, which has prompted us to conduct an
a posteriori analysis of the method deriving residual based estimators to drive
an adaptive algorithm. It is numerically shown that the optimal convergence
rates are regained upon using the adaptive procedure.


title:
Theory of metal-intercalated phenacenes: Why molecular valence 3 is
  special

abstract:
  We develop a correlated-electron minimal model for the normal state of
charged phenanthrene ions in the solid state, within the reduced space of the
two lowest antibonding molecular orbitals of phenanthrene. Our model is general
and can be easily extended to study the normal states of other polycyclic
aromatic hydrocarbon superconductors. The main difference between our approach
and previous correlated-electron theories of phenacenes is that our
calculations are exact within the reduced basis space, albeit for finite
clusters. The enhanced exchange of electron populations between these molecular
orbitals, driven by Coulomb interactions over and above the bandwidth effects,
gives a theoretical description of the phenanthrene trianions that is very
different from previous predictions. Exact many-body finite cluster
calculations show that while the systems with molecular charges of $-$1 and
$-$2 are one- and two-band Mott-Hubbard semiconductors, respectively, molecular
charge $-$3 gives two nearly $\frac{3}{4}$-filled bands, rather than a
completely filled lower band and a $\frac{1}{2}$-filled upper band. The carrier
density per active molecular orbital is thus nearly the same in the normal
state of the superconducting aromatics and organic charge-transfer solids, and
may be the key to understanding unconventional superconductivity in these
molecular superconductors.


title: MetaPar: Metagenomic Sequence Assembly via Iterative Reclassification

abstract:
  We introduce a parallel algorithmic architecture for metagenomic sequence
assembly, termed MetaPar, which allows for significant reductions in assembly
time and consequently enables the processing of large genomic datasets on
computers with low memory usage. The gist of the approach is to iteratively
perform read (re)classification based on phylogenetic marker genes and
assembler outputs generated from random subsets of metagenomic reads. Once a
sufficiently accurate classification within genera is performed, de novo
metagenomic assemblers (such as Velvet or IDBA-UD) or reference based
assemblers may be used for contig construction. We analyze the performance of
MetaPar on synthetic data consisting of 15 randomly chosen species from the
NCBI database through the effective gap and effective coverage metrics.


title: Two-Baryon Correlation Functions in 2-flavour QCD

abstract:
  We present first results for two-baryon correlation functions, computed using
$N_f=2$ flavours of O($a$) improved Wilson quarks, with the aim of explaining
potential dibaryon bound states, specifically the H-dibaryon. In particular, we
use a GEVP to isolate the groundstate using two-baryon (hyperon-hyperon)
correlation functions $\big(\langle C_{XY}(t)C_{XY}(0) \rangle$, where
$XY=\Lambda\Lambda, \Sigma\Sigma, N\Xi, \cdots\big)$, each of which has an
overlap with the H-dibaryon. We employ a `blocking' algorithm to handle the
large number of contractions, which may easily be extended to N-baryon
correlation functions. We also comment on its application to the analysis of
single baryon masses ($n$, $\Lambda$, $\Xi$, $\cdots$). This study is performed
on an isotropic lattice with $m_\pi = 460$ MeV, $m_\pi L = 4.7$ and $a = 0.063$
fm.


title:
Comparing the WFC3 IR Grism Stare and Spatial-Scan Observations for
  Exoplanet Characterization

abstract:
  We report on a detailed study of the measurement stability for WFC3 IR grism
stare and spatial scan observations. The excess measurement noise for both
modes is established by comparing the observed and theoretical measurement
uncertainties. We find that the stare-mode observations produce differential
measurements that are consistent and achieve $\sim\,1.3$ times photon-limited
measurement precision. In contrast, the spatial-scan mode observations produce
measurements which are inconsistent, non-Gaussian, and have higher excess noise
corresponding to $\sim\,2$ times the photon-limited precision. The inferior
quality of the spatial scan observations is due to spatial-temporal variability
in the detector performance which we measure and map. The non-Gaussian nature
of spatial scan measurements makes the use of $\chi^2$ and the determination of
formal confidence intervals problematic and thus renders the comparison of
spatial scan data with theoretical models or other measurements difficult. With
better measurement stability and no evidence for non-Gaussianity, stare mode
observations offer a significant advantage for characterizing transiting
exoplanet systems.


title: Numerical Approximations for Fractional Differential Equations

abstract:
  The Gr\"unwald and shifted Gr\"unwald formulas for the function $y(x)-y(b)$
are first order approximations for the Caputo fractional derivative of the
function $y(x)$ with lower limit at the point $b$. We obtain second and third
order approximations for the Gr\"unwald and shifted Gr\"unwald formulas with
weighted averages of Caputo derivatives when sufficient number of derivatives
of the function $y(x) $ are equal to zero at $b$, using the estimate for the
error of the shifted Gr\"unwald formulas. We use the approximations to
determine implicit difference approximations for the sub-diffusion equation
which have second order accuracy with respect to the space and time variables,
and second and third order numerical approximations for ordinary fractional
differential equations.


title: Numerical Stochastic Perturbation Theory and the Gradient Flow

abstract:
  We study the Yang-Mills gradient flow using numerical stochastic perturbation
theory. As an application of the method we consider the recently proposed
gradient flow coupling in the Schr\"odinger functional for the pure SU(3) gauge
theory.


title: Deciding Isomorphy using Dehn fillings, the splitting case

abstract:
  We solve Dehn's isomorphism problem for virtually torsion-free relatively
hyperbolic groups with nilpotent parabolic subgroups.
  We do so by reducing the isomorphism problem to three algorithmic problems in
the parabolic subgroups, namely the isomorphism problem, separation of torsion
(in their outer automorphism groups) by congruences, and the mixed Whitehead
problem, an automorphism group orbit problem. The first step of the reduction
is to compute canonical JSJ decompositions. Dehn fillings and the given
solutions of the algorithmic problems in the parabolic groups are then used to
decide if the graphs of groups have isomorphic vertex groups and, if so,
whether a global isomorphism can be assembled.
  For the class of finitely generated nilpotent groups, we give solutions to
these algorithmic problems by using the arithmetic nature of these groups and
of their automorphism groups.


title: Probing nonlinear adiabatic paths with a universal integrator

abstract:
  We apply a flexible numerical integrator to the simulation of adiabatic
quantum computation with nonlinear paths. We find that a nonlinear path may
significantly improve the performance of adiabatic algorithms versus the
conventional straight-line interpolations. The employed integrator is suitable
for solving the time-dependent Schr\"odinger equation for any qubit
Hamiltonian. Its flexible storage format significantly reduces cost for storage
and matrix-vector multiplication in comparison to common sparse matrix schemes.


title: Local computation mechanism design

abstract:
  We introduce the notion of Local Computation Mechanism Design - designing
game theoretic mechanisms which run in polylogarithmic time and space. Local
computation mechanisms reply to each query in polylogarithmic time and space,
and the replies to different queries are consistent with the same global
feasible solution. In addition, the computation of the payments is also done in
polylogarithmic time and space. Furthermore, the mechanisms need to maintain
incentive compatibility with respect to the allocation and payments.
  We present local computation mechanisms for a variety of classical
game-theoretical problems: 1. stable matching, 2. job scheduling, 3.
combinatorial auctions for unit-demand and k-minded bidders, and 4. the housing
allocation problem.
  For stable matching, some of our techniques may have general implications.
Specifically, we show that when the men's preference lists are bounded, we can
achieve an arbitrarily good approximation to the stable matching within a fixed
number of iterations of the Gale-Shapley algorithm.


title: A thick subcategory theorem for modules over certain ring spectra

abstract:
  We classify thick subcategories of the $\infty$-categories of perfect modules
over ring spectra which arise as functions on even periodic derived stacks
satisfying affineness and regularity conditions. For example, we show that the
thick subcategories of perfect modules over $\mathrm{TMF}$ are in natural
bijection with the subsets of the underlying space of the moduli stack of
elliptic curves which are closed under specialization.


title:
The effects of spatial resolution on Integral Field Spectrograph surveys
  at different redshifts. The CALIFA perspective

abstract:
  Over the past decade, 3D optical spectroscopy has become the preferred tool
for understanding the properties of galaxies and is now increasingly used to
carry out galaxy surveys. Low redshift surveys include SAURON, DiskMass,
ATLAS3D, PINGS and VENGA. At redshifts above 0.7, surveys such as MASSIV, SINS,
GLACE, and IMAGES have targeted the most luminous galaxies to study mainly
their kinematic properties. The on-going CALIFA survey ($z\sim0.02$) is the
first of a series of upcoming Integral Field Spectroscopy (IFS) surveys with
large samples representative of the entire population of galaxies. Others
include SAMI and MaNGA at lower redshift and the upcoming KMOS surveys at
higher redshift. Given the importance of spatial scales in IFS surveys, the
study of the effects of spatial resolution on the recovered parameters becomes
important. We explore the capability of the CALIFA survey and a hypothetical
higher redshift survey to reproduce the properties of a sample of objects
observed with better spatial resolution at lower redshift. Using a sample of
PINGS galaxies, we simulate observations at different redshifts. We then study
the behaviour of different parameters as the spatial resolution degrades with
increasing redshift.


title: The extended Brauer quotient for N-interior G-algebras

abstract:
  In this note we generalize the extended Brauer quotient defined by L. Puig
and Y. Zhou in [4, Section 3] to the case of N-interior G-algebras, where N is
a normal subgroup of a finite group G. We use this extended Brauer quotient on
permutation algebras to establish some correspondences that generalize known
results that hold in the group algebra case.


title: Investigation of the $U_A(1)$ in high temperature QCD on the lattice

abstract:
  In this project we study the effect of the $U_A(1)$ anomaly for (2+1)-flavour
QCD at high temperature. We apply the overlap operator as a tool to probe the
topological properties of gauge field configurations which have been generated
within the Highly Improved Staggered Quark (HISQ) discretization scheme on
lattices of size $32^3\times 8$ with $m_l/m_s=1/20$, commonly used for the
study of QCD thermodynamics. Although we have at present, only results for one
value of the quark masses and thus cannot monitor the change of the eigenvalue
distributions with the light quark mass, the distribution of the low-lying
eigenvalues of the overlap operator suggests that the $U_A(1)$ is not restored
effectively even at 1.5 times the pseudo critical temperature. The
corresponding low-lying eigenmodes show localization properties.


title:
A theorem of Mislin for cohomology of fusion systems and applications to
  block algebras of finite groups

abstract:
  We give an algebraic proof for a theorem of Mislin in the case of cohomology
of saturated fusion systems defined on p-groups when p is odd. Some
applications of this theorem to block algebras of finite groups are also given.


title: Thermal entanglement in a triple quantum dot system

abstract:
  We present studies of thermal entanglement of a three-spin system in
triangular symmetry. Spin correlations are described within an effective
Heisenberg Hamiltonian, derived from the Hubbard Hamiltonian, with
super-exchange couplings modulated by an effective electric field. Additionally
a homogenous magnetic field is applied to completely break the degeneracy of
the system. We show that entanglement is generated in the subspace of doublet
states with different pairwise spin correlations for the ground and excited
states. At low temperatures thermal mixing between the doublets with the same
spin destroys entanglement, however one can observe its restoration at higher
temperatures due to the mixing of the states with an opposite spin orientation
or with quadruplets (unentangled states) always destroys entanglement. Pairwise
entanglement is quantified using concurrence for which analytical formulae are
derived in various thermal mixing scenarios. The electric field plays a
specific role -- it breaks the symmetry of the system and changes spin
correlations. Rotating the electric field can create maximally entangled qubit
pairs together with a separate spin (monogamy) that survives in a relatively
wide temperature range providing robust pairwise entanglement generation at
elevated temperatures.


title: Untangling the Newman-Janis algorithm

abstract:
  Newman-Janis algorithm for Kerr-Newman geometry is reanalyzed in the light of
Cartan calculus.


title: On maximally inflected hyperbolic curves

abstract:
  In this note we study the distribution of real inflection points among the
ovals of a real non-singular hyperbolic curve of even degree. Using Hilbert's
method we show that for any integers $d$ and $r$ such that $4\leq r \leq
2d^2-2d$, there is a non-singular hyperbolic curve of degree $2d$ in $\mathbb
R^2$ with exactly $r$ line segments in the boundary of its convex hull. We also
give a complete classification of possible distributions of inflection points
among the ovals of a maximally inflected non-singular hyperbolic curve of
degree $6$.


title: Subword complexes and nil-Hecke moves

abstract:
  For a finite Coxeter group W, a subword complex is a simplicial complex
associated with a pair (Q, \rho), where Q is a word in the alphabet of simple
reflections, \rho is a group element. We describe the transformations of such a
complex induced by nil-moves and inverse operations on Q in the nil-Hecke
monoid corresponding to W. If the complex is polytopal, we also describe such
transformations for the dual polytope. For W simply-laced, these descriptions
and results of \cite{Go} provide an algorithm for the construction of the
subword complex corresponding to (Q, \rho) from the one corresponding to
(\delta(Q), \rho), for any sequence of elementary moves reducing the word Q to
its Demazure product \delta(Q). The former complex is spherical if and only if
the latter one is the (-1)-sphere.


title: Gyromagnetically Induced Transparency of Meta-Surfaces

abstract:
  We demonstrate that the violation of the time-reversal (TR) symmetry in the
presence of a gyromagnetic substrate can produce an analog of
electromagnetically induced transparency in metallic meta-molecules. The
simplest implementation of such gyromagnetically induced transparency (GIT) in
a meta-surface comprised of an array of resonant antenna pairs placed on a
gyromagnetic substrate and illuminated by a normally incident electromagnetic
wave is analyzed. TR symmetry breaking introduced by the magnetic field makes
meta-molecules bi-anisotropic and causes spectrally-sharp Fano interference
between the otherwise uncoupled electric and magnetic dipolar resonances of the
meta-molecules. The applied magnetic field results in a sharp transmission peak
through the otherwise reflective meta-surface. We show that, for oblique wave
incidence, one-way GIT can be achieved by the combination of spatial dispersion
and TR symmetry breaking. These theoretically predicted phenomena pave the way
to non-reciprocal switches and isolators that can be dynamically controlled by
electric currents.


title: A non-Abelian Chern-Simons--Yang-Mills-Higgs system in 3+1 dimensions

abstract:
  We study spherically symmetric solutions of an $SO(5)$
Chern-Simons--Yang-Mills-Higgs system in $3+1$ dimensions. The Chern-Simons
densities are defined in terms of both Yang-Mills fields and a $5$-component
isomultiplet Higgs. The $SO(3)\times{SO(2)}$ solutions are analysed in a
systematic way, by employing numerical methods. These finite energy
configurations possess both electric and magnetic global charges, differing
radically, however, from Julia-Zee dyons. When two or more of these
Chern-Simons densities are present in the Lagrangian, solutions with vanishing
electric charge but nonvanishing electrostatic potential may exist.


title: Long-range interacting systems and the Gibbs-Duhem equation

abstract:
  The generalized Gibbs-Duhem equation is obtained for systems with long-range
interactions in $d$ spatial dimensions. We consider that particles in the
system interact through a slowly decaying pair potential of the form $1/r^\nu$
with $0\leq\nu\leq d$. The local equation of state is obtained by computing the
local entropy per particle and using the condition of local thermodynamic
equilibrium. This local equation of state turns out to be that of an ideal gas.
Integrating the relation satisfied by local thermodynamic variables over the
volume, the equation involving global magnitudes is derived. Thus, the Euler
relation is found and we show that it is modified by the addition of a term
proportional to the total potential energy. This term is responsible for the
modification of the Gibbs-Duhem equation. We also point out a close
relationship between the thermodynamics of long-range interacting systems and
the thermodynamics of small systems introduced by Hill.