title:
Parallel Repetition of Entangled Games with Exponential Decay via the
  Superposed Information Cost

abstract:
  In a two-player game, two cooperating but non communicating players, Alice
and Bob, receive inputs taken from a probability distribution. Each of them
produces an output and they win the game if they satisfy some predicate on
their inputs/outputs. The entangled value $\omega^*(G)$ of a game $G$ is the
maximum probability that Alice and Bob can win the game if they are allowed to
share an entangled state prior to receiving their inputs.
  The $n$-fold parallel repetition $G^n$ of $G$ consists of $n$ instances of
$G$ where the players receive all the inputs at the same time and produce all
the outputs at the same time. They win $G^n$ if they win each instance of $G$.
  In this paper we show that for any game $G$ such that $\omega^*(G) = 1 -
\varepsilon < 1$, $\omega^*(G^n)$ decreases exponentially in $n$. First, for
any game $G$ on the uniform distribution, we show that $\omega^*(G^n) = (1 -
\varepsilon^2)^{\Omega\left(\frac{n}{\log(|I||O|)} -
|\log(\varepsilon)|\right)}$, where $|I|$ and $|O|$ are the sizes of the input
and output sets. From this result, we show that for any entangled game $G$,
$\omega^*(G^n) \le (1 - \varepsilon^2)^{\Omega(\frac{n}{Q\log(|I||O|)} -
\frac{|\log(\varepsilon)|}{Q})}$ where $p$ is the input distribution of $G$ and
$Q= \frac{|I|^2 \max_{xy} p_{xy}^2 }{\min_{xy} p_{xy} }$. This implies parallel
repetition with exponential decay as long as $\min_{xy} \{p_{xy}\} \neq 0$ for
general games. To prove this parallel repetition, we introduce the concept of
\emph{Superposed Information Cost} for entangled games which is inspired from
the information cost used in communication complexity.


title:
Nature of synchronization transitions in random networks of coupled
  oscillators

abstract:
  We consider a system of phase oscillators with random intrinsic frequencies
coupled through sparse random networks, and investigate how the connectivity
disorder affects the nature of collective synchronization transitions. Various
distribution types of intrinsic frequencies are considered: uniform, unimodal,
and bimodal distribution. We employ a heterogeneous mean-field approximation
based on the annealed networks and also perform numerical simulations on the
quenched Erdos-Renyi networks. We find that the connectivity disorder
drastically changes the nature of the synchronization transitions. In
particular, the quenched randomness completely wipes away the diversity of the
transition nature and only a continuous transition appears with the same
mean-field exponent for all types of frequency distributions. The physical
origin of this unexpected result is discussed.


title: Computing isogenies between supersingular elliptic curves over F_p

abstract:
  Let p>3 be a prime and let E, E' be supersingular elliptic curves over F_p.
We want to construct an isogeny phi: E --> E'. The currently fastest algorithm
for finding isogenies between supersingular elliptic curves solves this problem
by performing a "meet-in-the-middle" breadth-first search in the full
supersingular 2-isogeny graph over F_{p^2}. In this paper we consider the
structure of the isogeny graph of supersingular elliptic curves over F_p. We
give an algorithm to construct isogenies between such supersingular elliptic
curves that works faster than the usual algorithm. We then discuss how this
results can be used to obtain an improved algorithm for the general
supersingular isogeny problem.


title: Spectral transfer morphisms for unipotent affine Hecke algebras

abstract:
  In this paper we will give a complete classification of the spectral transfer
morphisms between the unipotent affine Hecke algebras of the various inner
forms of a given quasi-split absolutely simple algebraic group, defined over a
non-archimidean local field $\textbf{k}$ and split over an unramified extension
of $\textbf{k}$. As an application of these results, the results of [O4] on the
spectral correspondences associated with such morphisms and some results of
Ciubotaru, Kato and Kato [CKK] we prove a conjecture of Hiraga, Ichino and
Ikeda [HII] on the formal degrees and adjoint gamma factors for all unipotent
discrete series characters of unramified simple groups of adjoint type defined
over $\bf{k}$.


title:
Three-dimensional hydrodynamical CO5BOLD model atmospheres of red giant
  stars. III. Line formation in the atmospheres of giants located close to the
  base of RGB

abstract:
  We utilize state-of-the-art 3D hydrodynamical and classical 1D stellar model
atmospheres to study the influence of convection on the formation properties of
various atomic and molecular spectral lines in the atmospheres of four red
giant stars, located close to the base of the red giant branch, RGB
($T_{\mathrm eff}\approx5000$ K, $\log g=2.5$), and characterized by four
different metallicities, [M/H] = 0.0, -1.0, -2.0, -3.0. The role of convection
in the spectral line formation is assessed with the aid of abundance
corrections, i.e., the differences in abundances predicted for a given
equivalent width of a particular spectral line with the 3D and 1D model
atmospheres. We find that for lines of certain neutral atoms the abundance
corrections strongly depend both on metallicity of a given model atmosphere and
the line excitation potential. While abundance corrections for all lines of
both neutral and ionized elements tend to be small at solar metallicity, for
lines of neutral elements with low ionization potential and low-to-intermediate
$\chi$ they quickly increase with decreasing metallicity, reaching in their
extremes to -0.6...-0.8 dex. In all such cases the large abundance corrections
are due to horizontal temperature fluctuations in the 3D hydrodynamical models.
Abundance corrections of molecular lines are very sensitive to metallicity of
the underlying model atmosphere and may be larger (in absolute value) than -0.5
dex at [M/H] = -3.0 (-1.5 dex in the case of CO). We also find that an
approximate treatment of scattering in the 3D model calculations leads to the
abundance corrections that are altered by less than ~0.1 dex, both for atomic
and molecular (CO) lines, with respect to the model where scattering is treated
as true absorption throughout the entire atmosphere, with the largest
differences for the resonance and low-excitation lines.


title:
Evaluating Cache Coherent Shared Virtual Memory for Heterogeneous
  Multicore Chips

abstract:
  The trend in industry is towards heterogeneous multicore processors (HMCs),
including chips with CPUs and massively-threaded throughput-oriented processors
(MTTOPs) such as GPUs. Although current homogeneous chips tightly couple the
cores with cache-coherent shared virtual memory (CCSVM), this is not the
communication paradigm used by any current HMC. In this paper, we present a
CCSVM design for a CPU/MTTOP chip, as well as an extension of the pthreads
programming model, called xthreads, for programming this HMC. Our goal is to
evaluate the potential performance benefits of tightly coupling heterogeneous
cores with CCSVM.


title: On complete monomial ideals

abstract:
  In dimension two, we study complete monomial ideals combinatorially, their
Rees algebras and develop effective means to find their defining equations.


title:
Energy Efficiency Optimization in Relay-Assisted MIMO Systems with
  Perfect and Statistical CSI

abstract:
  A framework for energy-efficient resource allocation in a single-user,
amplify-and-forward relay-assisted MIMO system is devised in this paper.
Previous results in this area have focused on rate maximization or sum power
minimization problems, whereas fewer results are available when bits/Joule
energy efficiency (EE) optimization is the goal. The performance metric to
optimize is the ratio between the system's achievable rate and the total
consumed power. The optimization is carried out with respect to the source and
relay precoding matrices, subject to QoS and power constraints. Such a
challenging non-convex problem is tackled by means of fractional programming
and and alternating maximization algorithms, for various CSI assumptions at the
source and relay. In particular the scenarios of perfect CSI and those of
statistical CSI for either the source-relay or the relay-destination channel
are addressed. Moreover, sufficient conditions for beamforming optimality are
derived, which is useful in simplifying the system design. Numerical results
are provided to corroborate the validity of the theoretical findings.


title:
An Unsupervised Feature Learning Approach to Improve Automatic Incident
  Detection

abstract:
  Sophisticated automatic incident detection (AID) technology plays a key role
in contemporary transportation systems. Though many papers were devoted to
study incident classification algorithms, few study investigated how to enhance
feature representation of incidents to improve AID performance. In this paper,
we propose to use an unsupervised feature learning algorithm to generate higher
level features to represent incidents. We used real incident data in the
experiments and found that effective feature mapping function can be learnt
from the data crosses the test sites. With the enhanced features, detection
rate (DR), false alarm rate (FAR) and mean time to detect (MTTD) are
significantly improved in all of the three representative cases. This approach
also provides an alternative way to reduce the amount of labeled data, which is
expensive to obtain, required in training better incident classifiers since the
feature learning is unsupervised.


title: Finite Sample Bernstein -- von Mises Theorem for Semiparametric Problems

abstract:
  The classical parametric and semiparametric Bernstein -- von Mises (BvM)
results are reconsidered in a non-classical setup allowing finite samples and
model misspecification. In the case of a finite dimensional nuisance parameter
we obtain an upper bound on the error of Gaussian approximation of the
posterior distribution for the target parameter which is explicit in the
dimension of the nuisance and target parameters. This helps to identify the so
called \emph{critical dimension} $ p $ of the full parameter for which the BvM
result is applicable. In the important i.i.d. case, we show that the condition
"$ p^{3} / n $ is small" is sufficient for BvM result to be valid under general
assumptions on the model. We also provide an example of a model with the phase
transition effect: the statement of the BvM theorem fails when the dimension $
p $ approaches $ n^{1/3} $. The results are extended to the case of infinite
dimensional parameters with the nuisance parameter from a Sobolev class. In
particular we show near normality of the posterior if the smoothness parameter
$s$ exceeds 3/2.


title: Set-reconstructibility of Post classes

abstract:
  The clones of Boolean functions are classified in regard to
set-reconstructibility via a strong dichotomy result: the clones containing
only affine functions, conjunctions, disjunctions or constant functions are
set-reconstructible, whereas the remaing clones are not weakly reconstructible.


title: Parastatistical Factors for Cascade Emission of a Pair of Paraparticles

abstract:
  The empirical absence to date of particles obeying parastatistics in high
energy collider experiments might be due to their large masses and lack of
gauge couplings. If there is a portal to such particles, they might be cascade
emitted as a pair of para-Majorana neutrinos or as a pair of scalar
paraparticles. In this paper, for an assumed portal Lagrangian, the associated
parastatistical factors are obtained for the case of order p=2 parastatistics
and the, in general differing factors, for the cases of emission of a
non-degenerate or a degenerate pair of particles which obey normal statistics.


title:
Backhaul Limited Asymmetric Cooperation for MIMO Cellular Networks via
  Semidefinite Relaxation

abstract:
  Multicell cooperation has recently attracted tremendous attention because of
its ability to eliminate intercell interference and increase spectral
efficiency. However, the enormous amount of information being exchanged,
including channel state information and user data, over backhaul links may
deteriorate the network performance in a realistic system. This paper adopts a
backhaul cost metric that considers the number of active directional
cooperation links, which gives a first order measurement of the backhaul
loading required in asymmetric Multiple-Input Multiple-Output (MIMO)
cooperation. We focus on a downlink scenario for multi-antenna base stations
and single-antenna mobile stations. The design problem is minimizing the number
of active directional cooperation links and jointly optimizing the beamforming
vectors among the cooperative BSs subject to
signal-to-interference-and-noise-ratio (SINR) constraints at the mobile
station. This problem is non-convex and solving it requires combinatorial
search. A practical algorithm based on smooth approximation and semidefinite
relaxation is proposed to solve the combinatorial problem efficiently. We show
that semidefinite relaxation is tight with probability 1 in our algorithm and
stationary convergence is guaranteed. Simulation results show the saving of
backhaul cost and power consumption is notable compared with several baseline
schemes and its effectiveness is demonstrated.


title: Simulation of Stray Light Contamination on CHEOPS Detector

abstract:
  The aim of this work is to quantify the amount of Earth stray light that
reaches the CHEOPS (CHaracterising ExOPlanets Satellite) detector. It will
carry out follow-up measurements on transiting planets. This requires exquisite
data that can be acquired only by a space-borne observatory and by well
understood and mitigated sources of noise. Earth stray light is one of them
which becomes the most prominent noise for faint stars.
  A software suite was developed to evaluate the contamination by the stray
light. As the satellite will be launched in late 2017, the year 2018 is
analysed for three different altitudes. Given an visible region at any time,
the stray light contamination is simulated at the entrance of the telescope.
The amount that reaches the detector is, however, much lower, as it is reduced
by the point source transmittance function.
  Information about the faintest star visible in any direction in the sky is
therefore available and is compared to a potential list of targets. The
influence of both the visibility region and the unavoidable South Atlantic
Anomaly are also studied as well as the effect of a changing optical assembly.
A methodology to compute the visible region of the sky and the stray light flux
is described. Techniques to prepare the scheduling of the observation and a
possible way of calibrating the dark current and the map of hot pixels are
presented.
  The simulations show that there are seasonal variations on the amount of flux
received and on the altitude. However, the South Atlantic Anomaly impacts more
direly higher orbits. This high radiation region demand the interruption of the
science operations. Even if the viewing zone at low altitude is smaller, the
availability of instrument is greater. There exist two favoured regions for the
observations. The field of view is the widest then as the plane of the orbit
and of the terminator merge.


title:
EPOBF: Energy Efficient Allocation of Virtual Machines in High
  Performance Computing Cloud

abstract:
  Cloud computing has become more popular in provision of computing resources
under virtual machine (VM) abstraction for high performance computing (HPC)
users to run their applications. A HPC cloud is such cloud computing
environment. One of challenges of energy efficient resource allocation for VMs
in HPC cloud is tradeoff between minimizing total energy consumption of
physical machines (PMs) and satisfying Quality of Service (e.g. performance).
On one hand, cloud providers want to maximize their profit by reducing the
power cost (e.g. using the smallest number of running PMs). On the other hand,
cloud customers (users) want highest performance for their applications. In
this paper, we focus on the scenario that scheduler does not know global
information about user jobs and user applications in the future. Users will
request shortterm resources at fixed start times and non interrupted durations.
We then propose a new allocation heuristic (named Energy-aware and Performance
per watt oriented Bestfit (EPOBF)) that uses metric of performance per watt to
choose which most energy-efficient PM for mapping each VM (e.g. maximum of MIPS
per Watt). Using information from Feitelson's Parallel Workload Archive to
model HPC jobs, we compare the proposed EPOBF to state of the art heuristics on
heterogeneous PMs (each PM has multicore CPU). Simulations show that the EPOBF
can reduce significant total energy consumption in comparison with state of the
art allocation heuristics.


title:
Can we predict the mutation rate at the single nucleotide scale in the
  human genome?

abstract:
  It has been recently claimed that it is possible to predict the rate of de
novo mutation of each site in the human genome with almost perfect accuracy
(Michaelson et al. (2012) Cell, 151, 1431-1442). We show that this claim is
unwarranted. By considering the correlation between the rate of de novo
mutation and the predictions from the model of Michaelson et al., we show that
there could be substantial unexplained variance in the mutation rate. We also
demonstrate that the model of Michaelson et al. fails to capture a major
component of the variation in the mutation rate, that which is local but not
associated with simple context.


title:
Swinging between rotation and accretion power in a binary millisecond
  pulsar

abstract:
  We present the discovery of IGR J18245-2452, the first millisecond pulsar
observed to swing between a rotation-powered, radio pulsar state, and an
accretion-powered X-ray pulsar state (Papitto et al. 2013, Nature, 501, 517).
This transitional source represents the most convincing proof of the
evolutionary link shared by accreting neutron stars in low mass X-ray binaries,
and radio millisecond pulsars. It demonstrates that swings between these two
states take place on the same time-scales of luminosity variations of X-ray
transients, and are therefore most easily interpreted in terms of changes in
the rate of mass in-flow.
  While accreting mass, the X-ray emission of IGR J18245-2452 varies
dramatically on time-scales ranging from a second to a few hours. We interpret
a state characterised by a lower flux and pulsed fraction, and by sudden
increases of the hardness of the X-ray emission, in terms of the onset of a
magnetospheric centrifugal inhibition of the accretion flow. Prospects of
finding new members of the newly established class of transitional pulsars are
also briefly discussed.


title:
Spin correlations and Dzyaloshinskii-Moriya interaction in
  Cs$_2$CuCl$_4$

abstract:
  We report on electron spin resonance (ESR) studies of the spin relaxation in
Cs$_2$CuCl$_4$. The main source of the ESR linewidth at temperatures $T \leq
150$ K is attributed to the uniform Dzyaloshinskii-Moriya interaction. The
vector components of the Dzyaloshinskii-Moriya interaction are determined from
the angular dependence of the ESR spectra using a high-temperature
approximation. Both the angular and temperature dependence of the ESR linewidth
have been analyzed using a self-consistent quantum-mechanical approach. In
addition analytical expressions based on a quasi-classical picture for spin
fluctuations are derived, which show good agreement with the quantum-approach
for temperatures $T \geq 2J/k_{\rm B} \approx 15$ K. A small modulation of the
ESR linewidth observed in the $ac$-plane is attributed to the anisotropic
Zeeman interaction, which reflects the two magnetically nonequivalent Cu
positions.


title: Hadronic Gamma-Ray and Neutrino Emission from Cygnus X-3

abstract:
  Cygnus X-3 (Cyg X-3) is a remarkable Galactic microquasar (X-ray binary)
emitting from radio to $\gamma$-ray energies. In this paper, we consider
hadronic model of emission of $\gamma$-rays above 100 MeV and their
implications. We focus here on the joint $\gamma$-ray and neutrino production
resulting from proton-proton interactions within the binary system. We find
that the required proton injection kinetic power, necessary to explain the
$\gamma$-ray flux observed by AGILE and Fermi-LAT, is $L_p \sim
10^{38}\:\rm{erg\:s^{-1}}$, a value in agreement with the average bolometric
luminosity of the hypersoft state (when Cygnus X-3 was repeatedly observed to
produce transient $\gamma$-ray activity). If we assume an increase of the wind
density at the superior conjunction, the asymmetric production of $\gamma$-rays
along the orbit can reproduce the observed modulation. According to
observational constraints and our modelling, a maximal flux of high-energy
neutrinos would be produced for an initial proton distribution with a power-law
index $\alpha=2.4$. The predicted neutrino flux is almost two orders of
magnitude less than the 2-month IceCube sensitivity at $\sim$1 TeV. If the
protons are accelerated up to PeV energies, the predicted neutrino flux for a
prolonged "soft X-ray state" would be a factor of about 3 lower than the 1-year
IceCube sensitivity at $\sim$10 TeV. This study shows that, for a prolonged
soft state (as observed in 2006) possibly related with $\gamma$-ray activity
and a hard distribution of injected protons, Cygnus X-3 might be close to being
detectable by cubic-kilometer neutrino telescopes such as IceCube.


title:
Unidirectional laning and migrating cluster crystals in confined
  self-propelled particle systems

abstract:
  One standard approach to describe the collective behaviour of self-propelled
particles is the Vicsek model: point-like self-propelled particles tend to
align their migration directions to the ones of their nearer neighbours at each
time-step. Here we use a variant of the Vicsek model that includes pairwise
repulsive interactions. Confining the system between parallel walls can
qualitatively change its appearance: a laning state can emerge that is
different from the ones previously reported. All lanes show on average the same
migration direction of the contained particles with a finite separation
distance between the lanes. Furthermore, in certain parameter ranges we observe
collectively migrating clusters that arrange in an approximately hexagonal way.
We suggest that the mechanism behind these regular textures is an overreaction
in the alignment mechanism. Considering the more realistic scenario of
non-point-like particles in the presence of confining surfaces is generally
important for the comparison to experimental systems.


title:
Pressure-induced quantum critical and multicritical points in a
  frustrated spin liquid

abstract:
  The quantum spin liquid compound (C$_4$H$_{12}$N$_2$)Cu$_2$Cl$_6$ (PHCC) is
studied by $\mu$SR under hydrostatic pressures up to 23.6 kbar. At low
temperatures, pressure-induced incommensurate magnetic order is detected beyond
a quantum critical point at $P_c\sim4.3$ kbar. An additional phase transition
to a different ordered phase is observed at $P_1\sim 13.4$ kbar. The data
indicate that the high-pressure phase may be a commensurate one. The
established $(P-T)$ phase diagram reveals the corresponding pressure-induced
multicritical point at $P_1$, $T_1=2.0$ K.


title:
Two and Three-Pion Quantum Statistics Correlations in Pb-Pb Collisions
  at $\sqrt{s_{\rm NN}}=2.76$ TeV at the LHC

abstract:
  Correlations induced by quantum statistics are sensitive to the
spatio-temporal extent as well as dynamics of particle emitting sources in
heavy-ion collisions. In addition, such correlations can be used to search for
the presence of a coherent component of pion production. Two and three-pion
correlations of same and mixed-charge are measured at low relative momentum to
estimate the coherent fraction of charged pions in Pb-Pb collisions at
$\sqrt{s_{\rm NN}}=2.76$ TeV at the LHC with ALICE. The genuine three-pion
quantum statistics correlation is found to be suppressed relative to the
two-pion correlation based on the assumption of fully chaotic pion emission.
The suppression is observed to decrease with triplet momentum. The observed
suppression at low triplet momentum may correspond to a coherent fraction in
charged pion emission of 23% $\pm$ 8%.


title:
A desingularization of the moduli space of rank 2 Higgs bundles over a
  curve

abstract:
  Let $X$ be a smooth complex projective curve of genus $g\geq 3$. Let
$\mathbf{M}_2$ be the moduli space of semistable rank $2$ Higgs bundles with
trivial determinant over $X$. We construct a desingularization $\mathbf{S}$ of
$\mathbf{M}_2$ as a closed subvariety of a moduli space. We prove that
$\mathbf{S}$ is a nonsingular variety containing the stable locus of
$\mathbf{M}_2$ as an open dense subvariety. On the other hand, there is another
desingularization $\mathbf{K}$ of $\mathbf{M}_2$ obtained from Kirwan's
algorithm. We show that $\mathbf{S}$ can be obtained after two blow-downs of
$\mathbf{K}$.


title: A valence bond liquid on the honeycomb lattice

abstract:
  The honeycomb lattice material Li2RuO3 undergoes a dimerization of Ru4+
cations on cooling below 270C, where the magnetic susceptibility vanishes. We
use density functional theory calculations to show that this reflects the
formation of a 'valence bond crystal', with a strong bond disproportionation.
On warming, x-ray diffraction shows that discrete three-fold symmetry is
regained on average, and the dimerization apparently disappears. In contrast,
local structural measurements using high-energy x-rays, show that disordered
dimers survive at the nanoscale up to at least 650C. The high temperature phase
of Li2RuO3 is thus an example of a valence bond liquid, where thermal
fluctuations drive resonance between different dimer coverages, a classic
analogue of the resonating valence bond state often discussed in connection
with high T$_c$ cuprates.


title: Special functions and reversible three-term recurrence formula (R3TRF)

abstract:
  In the previous series "Special functions and three term recurrence formula
(3TRF)", I generalize the three term recurrence relation in the linear
differential equation for the infinite series and polynomial which makes B_n
term terminated including all higher terms of A_n's. In this series I will show
how to obtain the formula for the polynomial which makes A_n term terminated
including all higher terms of B_n's and infinite series of its power series
expansion. In the future series I will show you for the polynomial which makes
A_n and B_n terms terminated at same time; the power series, integral formalism
and generating function such as Heun, Mathieu, Lame and GCH equations will be
constructed analytically. In chapter 1, I will generalize the three term
recurrence relation in linear differential equation in a backward for the
infinite series and polynomial which makes A_n term terminated including all
higher terms of B_n's. In chapters 2-9, I will apply reversible three term
recurrence formula to (1) the power series expansion in closed forms, (2) its
integral representation and (3) generating functions of Heun, Confluent Heun,
GCH, Lame and Mathieu equations that consist of three term recursion relation
for the infinite series and polynomial which makes A_n term terminated.


title:
Bright soliton quantum superpositions: signatures of high- and
  low-fidelity states

abstract:
  Scattering quantum bright solitons off barriers has been predicted to lead to
nonlocal quantum superpositions, in particular the NOON-state. The focus of
this paper lies on signatures of both high- and low-fidelity quantum
superposition states. We numerically demonstrate that a one-dimensional
geometry with the barrier potential situated in the middle of an additional -
experimentally typical - harmonic confinement gives rise to particularly
well-observable signatures. In the elastic scattering regime we investigate
signatures of NOON-states on the $N$-particle level within an effective
potential approach. We show that removing the barrier potential and
subsequently recombining both parts of the quantum superposition leads to a
high-contrast interference pattern in the center-of-mass coordinate for narrow
and broad potential barriers. We demonstrate that the presented signatures can
be used to clearly distinguish quantum superpositions states from statistical
mixtures and are sufficiently robust against experimentally relevant
excitations of the center-of-mass wave function to higher lying oscillator
states. For two-particle solitons we extend these considerations to
low-fidelity superposition states: even for strong deviations from the
two-particle NOON-state we find interference patterns with high contrast.


title:
Smoothness-Constrained Image Recovery from Block-Based Random
  Projections

abstract:
  In this paper we address the problem of visual quality of images
reconstructed from block-wise random projections. Independent reconstruction of
the blocks can severely affect visual quality, by displaying artifacts along
block borders. We propose a method to enforce smoothness across block borders
by modifying the sensing and reconstruction process so as to employ partially
overlapping blocks. The proposed algorithm accomplishes this by computing a
fast preview from the blocks, whose purpose is twofold. On one hand, it allows
to enforce a set of constraints to drive the reconstruction algorithm towards a
smooth solution, imposing the similarity of block borders. On the other hand,
the preview is used as a predictor of the entire block, allowing to recover the
prediction error, only. The quality improvement over the result of independent
reconstruction can be easily assessed both visually and in terms of PSNR and
SSIM index.


title:
A Validation Framework for the Long Term Preservation of High Energy
  Physics Data

abstract:
  The study group on data preservation in high energy physics, DPHEP, is moving
to a new collaboration structure, which will focus on the implementation of
preservation projects, such as those described in the group's large scale
report published in 2012. One such project is the development of a validation
framework, which checks the compatibility of evolving computing environments
and technologies with the experiments software for as long as possible, with
the aim of substantially extending the lifetime of the analysis software, and
hence of the usability of the data. The framework is designed to automatically
test and validate the software and data of an experiment against changes and
upgrades to the computing environment, as well as changes to the experiment
software itself. Technically, this is realised using a framework capable of
hosting a number of virtual machine images, built with different configurations
of operating systems and the relevant software, including any necessary
external dependencies.


title:
Efficient and automatic methods for flexible regression on
  spatiotemporal data, with applications to groundwater monitoring

abstract:
  Fitting statistical models to spatiotemporal data requires finding the right
balance between imposing smoothness and following the data. In the context of
p-splines, we propose a Bayesian framework for choosing the smoothing parameter
which allows the construction of fully-automatic data-driven methods for
fitting flexible models to spatiotemporal data. A computationally efficient
implementation, exploiting the sparsity of the arising design and penalty
matrices, is proposed. The findings are illustrated using a simulation and two
examples, all concerned with the modelling of contaminants in groundwater,
which suggest that the proposed strategy is more stable that competing
strategies based on the use of criteria such as GCV and AIC.


title:
Searches for rare and forbidden kaon decays at the NA62 experiment at
  CERN

abstract:
  The decay $K^+ \to \pi^+\nu\bar{\nu}$ is highly suppressed in the Standard
Model (SM), while its rate can be predicted with minimal theoretical
uncertainty. The branching ratio (BR) for this decay is thus a sensitive probe
of the flavor sector of the SM; its measurement, however, is a significant
experimental challenge. The primary goal of the NA62 experiment is to measure
${\rm BR}(K^+ \to \pi^+\nu\bar{\nu})$ with $\sim$10% precision. This will
require the observation of $10^{13}$ $K^+$ decays in the experiment's fiducial
volume, as well as the use of high-performance systems for precision tracking,
particle identification, and photon vetoing. These aspects of the experiment
will also allow NA62 to carry out a rich program of searches for lepton flavor
and/or number violating $K^+$ decays. Part of the experimental apparatus was
commissioned during a technical run in 2012; installation continues and data
taking is expected to begin in late 2014. The physics prospects and the status
of the NA62 experiment are reviewed.


title: Influence of sample geometry on inductive damping measurement methods

abstract:
  We study the precession frequency and effective damping of patterned
permalloy thin films of different geometry using integrated inductive test
structures. The test structures consist of coplanar wave guides fabricated onto
patterned permalloy stripes of different geometry. The width, length and
position of the permalloy stripe with respect to the center conductor of the
wave guide are varied. The precession frequency and effective damping of the
different devices is derived by inductive measurements in time and frequency
domain in in-plane magnetic fields. While the precession frequencies do not
reveal a significant dependence on the sample geometry we find a decrease of
the measured damping with increasing width of the permalloy centered underneath
the center conductor of the coplanar wave guide. We attribute this effect to an
additional damping contribution due to inhomogeneous line broadening at the
edges of the permalloy stripes which does not contribute to the inductive
signal provided the permalloy stripe is wider than the center conductor.
Consequences for inductive determination of the effective damping using such
integrated reference samples are discussed.


title: Thermal field theories and shifted boundary conditions

abstract:
  The analytic continuation to an imaginary velocity of the canonical partition
function of a thermal system expressed in a moving frame has a natural
implementation in the Euclidean path-integral formulation in terms of shifted
boundary conditions. The Poincare' invariance underlying a relativistic theory
implies a dependence of the free-energy on the compact length L_0 and the shift
xi only through the combination beta=L_0(1+xi^2)^(1/2). This in turn implies
that the energy and the momentum distributions of the thermal theory are
related, a fact which is encoded in a set of Ward identities among the
correlators of the energy-momentum tensor. The latter have interesting
applications in lattice field theory: they offer novel ways to compute
thermodynamic potentials, and a set of identities to renormalize
non-perturbatively the energy-momentum tensor. At fixed bare parameters the
shifted boundary conditions also provide a simple method to vary the
temperature in much smaller steps than with the standard procedure.


title:
Quantum limit for nuclear spin polarization in semiconductor quantum
  dots

abstract:
  A recent experiment [E. A. Chekhovich et al., Phys. Rev. Lett. 104, 066804
(2010)] has demonstrated that high nuclear spin polarization can be achieved in
self-assembled quantum dots by exploiting an optically forbidden transition
between a heavy hole and a trion state. However, a fully polarized state is not
achieved as expected from a classical rate equation. Here, we theoretically
investigate this problem with the help of a quantum master equation and we
demonstrate that a fully polarized state cannot be achieved due to formation of
a nuclear dark state. Moreover, we show that the maximal degree of polarization
depends on structural properties of the quantum dot.


title: On stable reconstructions from nonuniform Fourier measurements

abstract:
  We consider the problem of recovering a compactly-supported function from a
finite collection of pointwise samples of its Fourier transform taking
nonuniformly. First, we show that under suitable conditions on the sampling
frequencies - specifically, their density and bandwidth - it is possible to
recover any such function $f$ in a stable and accurate manner in any given
finite-dimensional subspace; in particular, one which is well suited for
approximating $f$. In practice, this is carried out using so-called nonuniform
generalized sampling (NUGS). Second, we consider approximation spaces in one
dimension consisting of compactly supported wavelets. We prove that a linear
scaling of the dimension of the space with the sampling bandwidth is both
necessary and sufficient for stable and accurate recovery. Thus wavelets are up
to constant factors optimal spaces for reconstruction.


title: Beyond Landauer erasure

abstract:
  In thermodynamics one considers thermal systems and the maximization of
entropy subject to the conservation of energy. A consequence is Landauer's
erasure principle, which states that the erasure of 1 bit of information
requires a minimum energy cost equal to $kT\ln(2)$ where $T$ is the temperature
of a thermal reservoir used in the process and $k$ is Boltzmann's constant.
Jaynes, however, argued that the maximum entropy principle could be applied to
any number of conserved quantities which would suggest that information erasure
may have alternative costs. Indeed we showed recently that by using a reservoir
comprising energy degenerate spins and subject to conservation of angular
momentum, the cost of information erasure is in terms of angular momentum
rather than energy. Here we extend this analysis and derive the minimum cost of
information erasure for systems where different conservation laws operate. We
find that, for each conserved quantity, the minimum resource needed to erase 1
bit of memory is $\lambda^{-1}\ln(2)$ where $\lambda$ is related to the average
value of the conserved quantity. The costs of erasure depend, fundamentally, on
both the nature of the physical memory element and the reservoir with which it
is coupled.


title:
Development of multi-platform control and instrumentation communications
  to increase operational reliability - application to MAST

abstract:
  Improving the reliability and reducing the maintenance time to give increased
availability is a key feature of developing control & instrumentation (C&I)
systems relevant to future fusion devices such as DEMO and to fusion power
plants. Standardising access to the multiple platforms comprising C&I systems
on working plant including software that analyses data is one aspect of
achieving this. This has been realised on the MAST Neutral Beam Injection
system (MNBI) following an extensive upgrade to the C&I, to improve the
operational reliability of the neutral beam plant.


title: Explicit rank bounds for cyclic covers

abstract:
  Let $M$ be a closed, orientable hyperbolic 3-manifold and $\phi$ a
homomorphism of its fundamental group onto $\mathbb{Z}$ that is not induced by
a fibration over the circle. For each natural number $n$ we give an explicit
lower bound, linear in $n$, on rank of the fundamental group of the cover of
$M$ corresponding to $\phi^{-1}(n\mathbb{Z})$. The key new ingredient is the
following result: for such a manifold $M$ and a connected, two-sided
incompressible surface of genus $g$ in $M$ that is not a fiber or semi-fiber, a
reduced homotopy in $(M,S)$ has length at most $14g-12$.


title: Spontaneous tensor properties for multiferroic phases

abstract:
  We have constructed dichromatic matrices of property coefficients for all
1601 Aizu species. This involves 122 non-magnetic Aizu species and extends the
work to the 773 species of phase transitions from disordered magnetic
prototypic (parent) phases and the 616 species from ordered magnetic prototypic
phases. In addition to coefficients describing the non-magnetic effects we have
included the coefficients of pyromagnetic, magnetoelectric, piezomagnetic
effects, and magnetic susceptibility. All components of these property tensors
are displayed in 13 by 13 matrices; non-zero components of the prototypic phase
are given in black and the spontaneous coefficients, that are non-zero in the
ferroic phase and zero in the prototypic phase, are given in red.


title: Quantifying Networks Complexity from Information Geometry Viewpoint

abstract:
  We consider a Gaussian statistical model whose parameter space is given by
the variances of random variables. Underlying this model we identify networks
by interpreting random variables as sitting on vertices and their correlations
as weighted edges among vertices. We then associate to the parameter space a
statistical manifold endowed with a Riemannian metric structure (that of
Fisher-Rao). Going on, in analogy with the microcanonical definition of entropy
in Statistical Mechanics, we introduce an entropic measure of networks
complexity. We prove that it is invariant under networks isomorphism. Above
all, considering networks as simplicial complexes, we evaluate this entropy on
simplexes and find that it monotonically increases with their dimension.


title:
On Grioli's minimum property and its relation to Cauchy's polar
  decomposition

abstract:
  The unitary polar factor of a matrix F is the unitary matrix Q realizing the
minimum of the norm of F-Q over all unitary matrices Q. Tracing back the
development on the optimality of the polar factor to its presumable roots, in
this paper we present a commented translation of a note by G. Grioli from 1940
(Boll.Un.Math.Ital.2,452-455(1940)) showing the minimization property for the
Frobenius norm in dimension 3; in his words:
  "We show that for the homogeneous displacement, tangent to any finite
displacement, there exists a minimum property completely analogous to a well
known property valid for infinitesimal displacements."
  Keywords: polar decomposition, optimality of the polar factor, Euclidean
distance, geodesic distance, Euclidean movement


title: A $N_F$-Dependent VFNS for Heavy Flavors: Merging the FFNS and VFNS

abstract:
  We introduce a Hybrid Variable Flavor Number Scheme (H-VFNS) for heavy
flavors, which incorporates the advantages of both the traditional Variable
Flavor Number Scheme (VFNS) as well as the Fixed Flavor Number Scheme (FFNS).
We include an explicit dependence on number of active flavors $N_F$ in both the
Parton Distribution Functions (PDFs) and the strong coupling constant
$\alpha_{S}$. This results in sets of coexisting PDFs and $\alpha_{S}$ for
$N_F=\{3,4,5,6\}$, that are related analytically by the $\overline{\rm MS}$
matching conditions. The H-VFNS resums the heavy quark contributions and
provides the freedom to choose the optimal $N_F$ for each particular data set.
Thus, we can fit selected HERA data in a FFNS framework, while retaining the
benefits of the VFNS to analyze LHC data at high scales. We illustrate how such
a fit can be implemented for the case of both HERA and LHC data.


title: A Complete Parameterized Complexity Analysis of Bounded Planning

abstract:
  The propositional planning problem is a notoriously difficult computational
problem, which remains hard even under strong syntactical and structural
restrictions. Given its difficulty it becomes natural to study planning in the
context of parameterized complexity. In this paper we continue the work
initiated by Downey, Fellows and Stege on the parameterized complexity of
planning with respect to the parameter "length of the solution plan." We
provide a complete classification of the parameterized complexity of the
planning problem under two of the most prominent syntactical restrictions,
i.e., the so called PUBS restrictions introduced by Baeckstroem and Nebel and
restrictions on the number of preconditions and effects as introduced by
Bylander. We also determine which of the considered fixed-parameter tractable
problems admit a polynomial kernel and which don't.


title: About Summarization in Large Fuzzy Databases

abstract:
  Moved by the need increased for modeling of the fuzzy data, the success of
the systems of exact generation of summary of data, we propose in this paper, a
new approach of generation of summary from fuzzy data called Fuzzy-SaintEtiQ.
This approach is an extension of the SaintEtiQ model to support the fuzzy data.
It presents the following optimizations such as 1) the minimization of the
expert risk; 2) the construction of a more detailed and more precise summaries
hierarchy, and 3) the co-operation with the user by giving him fuzzy summaries
in different hierarchical levels


title:
Revealing A Universal Planet-Metallicity Correlation For Planets of
  Different Sizes Around Solar-Type Stars

abstract:
  The metallicity of exoplanet systems serves as a critical diagnostic of
planet formation mechanisms. Previous studies have demonstrated the
planet-metallicity correlation for large planets ($R_P\ \geq\ 4\ R_E$);
however, a correlation has not been found for smaller planets. With a sample of
406 $Kepler$ Objects of Interest whose stellar properties are determined
spectroscopically, we reveal a universal planet-metallicity correlation: not
only gas-giant planets ($3.9\ R_E\ < R_P\ \leq\ 22.0\ R_E$) but also gas-dwarf
($1.7\ R_E\ < R_P\ \leq\ 3.9\ R_E$) and terrestrial planets ($R_P\ \leq\ 1.7\
R_E$) occur more frequently in metal-rich stars. The planet occurrence rates of
gas-giant planets, gas-dwarf planets, and terrestrial planets are
$9.30^{+5.62}_{-3.04}$, $2.03^{+0.29}_{-0.26}$, and $1.72^{+0.19}_{-0.17}$
times higher for metal-rich stars than for metal-poor stars, respectively.


title: Accretion onto a higher dimensional black hole

abstract:
  We examine the steady-state spherically symmetric accretion of relativistic
fluids, with a polytropic equation of state, onto a higher dimensional
Schwarzschild black hole. The mass accretion rate, critical radius, and flow
parameters are determined and compared with results obtained in standard four
dimensions. The accretion rate, $\dot{M}$, is an explicit function of the black
hole mass, $M$, as well as the gas boundary conditions and the dimensionality,
$D$, of the spacetime. We also find the asymptotic compression ratios and
temperature profiles below the accretion radius and at the event horizon. This
analysis is a generalization of Michel's solution to higher dimensions and of
the Newtonian expressions of Giddings and Mangano which considers the accretion
of TeV black holes.


title: Exploring Higgs Sector Spectroscopy

abstract:
  The Higgs sector of the standard model is field-theoretically a very
interesting theory. Because strong and weak coupling domains are continuously
connected, only quantitative changes distinguish the various regions.
Especially, this is true for the asymptotic spectrum, which can only consist
out of gauge-invariant composite, i. e. bound, states. Since in some regions of
parameter space even Regge trajectories are expected to exist, there is
immediately the possibility that resonances may also be present in the
parameter region characteristic of the standard model Higgs sector. This
possibility is discussed in some detail, starting from the definition of the
theory to spectroscopy, including excited state analysis, to some
considerations whether this could have experimental consequences. The strongest
limitation for this exploration turns out to be that the gauge coupling without
fermions runs much faster, and the gauge sector is therefore potentially
affected.


title:
Charged lepton flavour violation in supersymmetric and holographic
  composite Higgs models with flavour symmetries

abstract:
  We discuss charged lepton flavour violating processes such as mu -> e gamma
in supersymmetric extensions of the Standard Model and in models with
gauge-Higgs unification and a warped extra dimension. In both classes of models
the processes turn out to be compatible with present experimental bounds, but
can be detected by future experiments, thanks to the presence of a flavour
symmetry G_f which constrains the form of the relevant couplings. The symmetry
G_f is chosen to be finite, discrete and non-abelian and also helps to predict
the peculiar lepton mixing pattern.


title:
Improved Approximation Algorithms for Matroid and Knapsack Median
  Problems and Applications

abstract:
  We consider the {\em matroid median} problem \cite{KrishnaswamyKNSS11},
wherein we are given a set of facilities with opening costs and a matroid on
the facility-set, and clients with demands and connection costs, and we seek to
open an independent set of facilities and assign clients to open facilities so
as to minimize the sum of the facility-opening and client-connection costs. We
give a simple 8-approximation algorithm for this problem based on LP-rounding,
which improves upon the 16-approximation in \cite{KrishnaswamyKNSS11}. Our
techniques illustrate that much of the work involved in the rounding algorithm
of in \cite{KrishnaswamyKNSS11} can be avoided by first converting the LP
solution to a half-integral solution, which can then be rounded to an integer
solution using a simple uncapacitated-facility-location (UFL) style clustering
step. We illustrate the power of these ideas by deriving: (a) a
24-approximation algorithm for matroid median with penalties, which is a vast
improvement over the 360-approximation obtained in \cite{KrishnaswamyKNSS11};
and (b) an 8-approximation for the {\em two-matroid median} problem, a
generalization of matroid median that we introduce involving two matroids. We
show that a variety of seemingly disparate facility-location problems
considered in the literature---data placement problem, mobile facility
location, $k$-median forest, metric uniform minimum-latency UFL---in fact
reduce to the matroid median or two-matroid median problems, and thus obtain
improved approximation guarantees for all these problems. Our techniques also
yield an improvement for the knapsack median problem.


title:
Change of variables as a method to study general $\beta$-models: bulk
  universality

abstract:
  We consider $\beta$ matrix models with real analytic potentials. Assuming
that the corresponding equilibrium density $\rho$ has a one-interval support
(without loss of generality $\sigma=[-2,2]$), we study the transformation of
the correlation functions after the change of variables
  $\lambda_i\to\zeta(\lambda_i)$ with $\zeta(\lambda)$ chosen from the equation
$\zeta'(\lambda)\rho(\zeta(\lambda))=\rho_{sc}(\lambda)$, where
$\rho_{sc}(\lambda)$ is the standard semicircle density. This gives us the
"deformed" $\beta$-model which has an additional "interaction" term. Standard
transformation with the Gaussian integral allows us to show that the "deformed"
$\beta$-model may be reduced to the standard Gaussian $\beta$-model with a
small perturbation $n^{-1}h(\lambda)$. This reduces most of the problems of
local and global regimes for $\beta$-models to the corresponding problems for
the Gaussian $\beta$-model with a small perturbation. In the present paper we
prove the bulk universality of local eigenvalue statistics for both one-cut and
multi-cut cases.


title: Effective mass signatures in multiphoton pair production

abstract:
  Electron-positron pair production in oscillating electric fields is
investigated in the nonperturbative threshold regime. Accurate numerical
solutions of quantum kinetic theory for corresponding observables are presented
and analyzed in terms of a proposed model for an effective mass of electrons
and positrons acquired within the given strong electric field. Although this
effective mass cannot provide an exact description of the collective
interaction of a charged particle with the strong field, physical observables
are identified which carry direct and sensitive signatures of the effective
mass.


title:
The counterpart/s of IGR J20159+3713/SWIFT J2015.9+3715: dissecting a
  complex region with emission from keV to TeV

abstract:
  We report on the identification of a new soft gamma-ray source, namely IGR
J20159+3713/SWIFT J2015.9+3715, first detected by INTEGRAL/IBIS and then
confirmed by Swift/BAT. The source, which has an observed 20-100 keV flux in
the range (0.7-1.4) x 10^(-11) erg cm^(-2) s^(-1), encloses a Fermi variable
source (2FGL J2015.6+3709) and is spatially close to a TeV emitter (VER
J2016+372). Thanks to X-ray follow-up observations performed with the X-ray
telescope on board Swift, we have been able to identify the new IBIS/BAT
detection with the combined emission of the blazar B2013+370 and the
cataclysmic variable RX J2015.6+3711. Both objects show variability in X-rays,
with the CV being the most variable of the two. At high energies (above 20 keV)
the emission is likely dominated by B2013+370, but the contribution from RX
J2015.6+3711 is not negligible. The blazar emits up to GeV frequencies where it
is seen by Fermi, while the cataclysmic variable has a bremsstrahlung
temperature which is too low to provide any contribution at these high
energies. These findings also indicate that the INTEGRAL/Swift source is not
associated with the TeV emission, which is most likely due to the supernova
remnant (SNR)/pulsar wind nebula (PWN) CTB 87.


title: A spectral mean for point sampled closed curves

abstract:
  We propose a spectral mean for closed curves described by sample points on
its boundary subject to mis-alignment and noise. First, we ignore mis-alignment
and derive maximum likelihood estimators of the model and noise parameters in
the Fourier domain. We estimate the unknown curve by back-transformation and
derive the distribution of the integrated squared error. Then, we model
mis-alignment by means of a shifted parametric diffeomorphism and minimise a
suitable objective function simultaneously over the unknown curve and the
mis-alignment parameters. Finally, the method is illustrated on simulated data
as well as on photographs of Lake Tana taken by astronauts during a Shuttle
mission.


title:
Achieving maximum energy-efficiency in multi-relay OFDMA cellular
  networks: a fractional programming approach

abstract:
  In this paper, the joint power and subcarrier allocation problem is solved in
the context of maximizing the energy-efficiency (EE) of a multi-user,
multi-relay orthogonal frequency division multiple access (OFDMA) cellular
network, where the objective function is formulated as the ratio of the
spectral-efficiency (SE) over the total power dissipation. It is proven that
the fractional programming problem considered is quasi-concave so that
Dinkelbach's method may be employed for finding the optimal solution at a low
complexity. This method solves the above-mentioned master problem by solving a
series of parameterized concave secondary problems. These secondary problems
are solved using a dual decomposition approach, where each secondary problem is
further decomposed into a number of similar subproblems. The impact of various
system parameters on the attainable EE and SE of the system employing both EE
maximization (EEM) and SE maximization (SEM) algorithms is characterized. In
particular, it is observed that increasing the number of relays for a range of
cell sizes, although marginally increases the attainable SE, reduces the EE
significantly. It is noted that the highest SE and EE are achieved, when the
relays are placed closer to the BS to take advantage of the resultant
line-of-sight link. Furthermore, increasing both the number of available
subcarriers and the number of active user equipment (UE) increases both the EE
and the total SE of the system as a benefit of the increased frequency and
multi-user diversity, respectively. Finally, it is demonstrated that as
expected, increasing the available power tends to improve the SE, when using
the SEM algorithm. By contrast, given a sufficiently high available power, the
EEM algorithm attains the maximum achievable EE and a suboptimal SE.


title: A New Push-Relabel Algorithm for Sparse Networks

abstract:
  In this paper, we present a new push-relabel algorithm for the maximum flow
problem on flow networks with $n$ vertices and $m$ arcs. Our algorithm computes
a maximum flow in $O(mn)$ time on sparse networks where $m = O(n)$. To our
knowledge, this is the first $O(mn)$ time push-relabel algorithm for the $m =
O(n)$ edge case; previously, it was known that push-relabel implementations
could find a max-flow in $O(mn)$ time when $m = \Omega(n^{1+\epsilon})$ (King,
et. al., SODA `92). This also matches a recent flow decomposition-based
algorithm due to Orlin (STOC `13), which finds a max-flow in $O(mn)$ time on
sparse networks.
  Our main result is improving on the Excess-Scaling algorithm (Ahuja & Orlin,
1989) by reducing the number of nonsaturating pushes to $O(mn)$ across all
scaling phases. This is reached by combining Ahuja and Orlin's algorithm with
Orlin's compact flow networks. A contribution of this paper is demonstrating
that the compact networks technique can be extended to the push-relabel family
of algorithms. We also provide evidence that this approach could be a promising
avenue towards an $O(mn)$-time algorithm for all edge densities.


title: Tunneling Magneto-Thermopower in Magnetic Tunnel Junctions

abstract:
  Thermally induced spin-dependent transport across magnetic tunnel junctions
is theoretically investigated. We analyze the thermal analog of Slonczewski's
model (as well as its limiting case---Julliere's model) of tunneling
magnetoresistance and obtain analytical expressions for the junction
thermopower and the tunneling magneto-thermopower (TMT). The analytical model
is tested numerically for the special case of an Al$_2$O$_3$-based MTJ, for
which we analyze the dependence of the thermopower and TMT on the relative
magnetization orientations, as well as on the barrier height and thickness. We
show that at a certain barrier height TMT vanishes, separating the region of
positive and negative TMT. As its electrical prototype, this thermal spin
transport model should serve as a phenomenological benchmark for analyzing
experimental and first-principles calculations of thermopower in magnetic
tunnel junctions. The analytical expressions can be used as a first estimate of
the magneto-thermopower of the junctions using {\it ab initio} band structure
data of the junction ferromagnets.


title: Optically Controlled Excitonic Transistor

abstract:
  Optical control of exciton fluxes is realized for indirect excitons in a
crossed-ramp excitonic device. The device demonstrates experimental proof of
principle for all-optical excitonic transistors with a high ratio between the
excitonic signal at the optical drain and the excitonic signal due to the
optical gate. The device also demonstrates experimental proof of principle for
all-optical excitonic routers.


title: Mathieu subspaces of codimension less than n of Mat_n(K)

abstract:
  We classify all Mathieu subspaces of ${\rm Mat}_n(K)$ of codimension less
than $n$, under the assumption that ${\rm char\,} K = 0$ or ${\rm char\,} K \ge
n$.
  More precisely, we show that any proper Mathieu subspace of ${\rm Mat}_n(K)$
of codimension less than $n$ is a subspace of $\{M \in {\rm Mat}_n(K) \mid {\rm
tr\,} M = 0\}$ if ${\rm char\,} K = 0$ or ${\rm char\,} K \ge n$. On the other
hand, we show that every subspace of $\{M \in {\rm Mat}_n(K) \mid {\rm tr\,} M
= 0\}$ of codimension less than $n$ in ${\rm Mat}_n(K)$ is a Mathieu subspace
of ${\rm Mat}_n(K)$ if ${\rm char\,} K = 0$ or ${\rm char\,} K \ge n+1$.


title:
A note on invariant subspaces and the solution of some classical
  functional equations

abstract:
  We study the continuous solutions of several classical functional equations
by using the properties of the spaces of continuous functions which are
invariant under some elementary linear trans-formations. Concretely, we use
that the sets of continuous solutions of certain equations are closed vector
subspaces of $C(\mathbb{C}^d,\mathbb{C})$ which are invariant under affine
transformations $T_{a,b}(f)(z)=f(az+b)$, or closed vector subspaces of
$C(\mathbb{R}^d,\mathbb{R})$ which are translation and dilation invariant.
These spaces have been recently classified by Sternfeld and Weit, and Pinkus,
respectively, so that we use this information to give a direct characterization
of the continuous solutions of the corresponding functional equations.


title:
Kullback-Leibler Approximation for Probability Measures on Infinite
  Dimensional Spaces

abstract:
  In a variety of applications it is important to extract information from a
probability measure $\mu$ on an infinite dimensional space. Examples include
the Bayesian approach to inverse problems and possibly conditioned) continuous
time Markov processes. It may then be of interest to find a measure $\nu$, from
within a simple class of measures, which approximates $\mu$. This problem is
studied in the case where the Kullback-Leibler divergence is employed to
measure the quality of the approximation. A calculus of variations viewpoint is
adopted and the particular case where $\nu$ is chosen from the set of Gaussian
measures is studied in detail. Basic existence and uniqueness theorems are
established, together with properties of minimising sequences. Furthermore,
parameterisation of the class of Gaussians through the mean and inverse
covariance is introduced, the need for regularisation is explained, and a
regularised minimisation is studied in detail. The calculus of variations
framework resulting from this work provides the appropriate underpinning for
computational algorithms.


title:
Long-range and short-range multiparticle correlation in collisions of
  $_{79}Au^{197}$ 10.7 A GeV with photoemulsion nuclei

abstract:
  A search and research of long-range and short-range multiparticle
correlations in pseudorapidity distribution of secondary particles on the base
of analysis of individual interaction of nuclei of $^{197}Au$ at energy 10.7
AGeV with photoemulsion nuclei, is carried out. Events with long-range
multiparticle correlations (LC), short-range multiparticle correlations (SC)
and mixed type (MT) in pseudorapidity distribution of secondary particles, are
selected by Hurst method in accordance of Hurst curve behavior. These types
have significantly different characteristics. At first, they have different
parameters of fragmentation. Events of LC type are processes of full
destruction of projectile nucleus, in which multicharge fragments are absent.
In events of mixed type several multicharge fragments of projectile nucleus are
discovered. Secondly, these two types have significantly different multiplicity
distribution. Mean multiplicity of LC type events is significantly more than in
events of mixed type.
  On the basis of research of dependence of multiplicity versus target-nuclei
fragments number for events of various types it is revealed, that the most
considerable multiparticle correlations are observed in interactions of mixed
type, which correspond to the central collisions of gold nuclei and nuclei of
CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge,
etc. Such events are characterised by full destruction of target-nucleus and
disintegration of projectile-nucleus on several multi-charged fragments.


title: Self-Quenching of Nuclear Spin Dynamics in Central Spin Problem

abstract:
  We consider, in the framework of the central spin $s=1/2$ model, driven
dynamics of two electrons in a double quantum dot subject to hyperfine
interaction with nuclear spins and spin-orbit coupling. The nuclear subsystem
dynamically evolves in response to Landau-Zener singlet-triplet transitions of
the electronic subsystem controlled by external gate voltages. Without noise
and spin-orbit coupling, subsequent Landau-Zener transitions die out after
about $10^4$ sweeps, the system self-quenches, and nuclear spins reach one of
the numerous glassy dark states. We present an analytical model that captures
this phenomenon. We also account for the multi-nuclear-specie content of the
dots and numerically determine the evolution of around $10^7$ nuclear spins in
up to $2\times10^5$ Landau-Zener transitions. Without spin-orbit coupling,
self-quenching is robust and sets in for arbitrary ratios of the nuclear spin
precession times and the waiting time between Landau-Zener sweeps as well as
under moderate noise. In presence of spin-orbit coupling of a moderate
magnitude, and when the waiting time is in resonance with the precession time
of one of the nuclear species, the dynamical evolution of nuclear polarization
results in stroboscopic screening of spin-orbit coupling. However, small
deviations from the resonance or strong spin-orbit coupling destroy this
screening. We suggest that the success of the feedback loop technique for
building nuclear gradients is based on the effect of spin-orbit coupling.


title: Waveguide-Coupled Photonic Crystal Cavity for Quantum Dot Spin Readout

abstract:
  We present a waveguide-coupled photonic crystal H1 cavity structure in which
the orthogonal dipole modes couple to spatially separated photonic crystal
waveguides. Coupling of each cavity mode to its respective waveguide with equal
efficiency is achieved by adjusting the position and orientation of the
waveguides. The behavior of the optimized device is experimentally verified for
where the cavity mode splitting is larger and smaller than the cavity mode
linewidth. In both cases, coupled Q-factors up to 1600 and contrast ratios up
to 10 are achieved. This design may allow for spin state readout of a
self-assembled quantum dot positioned at the cavity center or function as an
ultra-fast optical switch operating at the single photon level.


title:
Reply to "Comment on `Quantum versus classical instability of scalar
  fields in curved backgrounds'"

abstract:
  We show that the reasoning which led the author of arXiv:1310.6252 to reach
his conclusions relies on an incorrect criterion for the existence of
normalizable bound solutions. We reinforce that the general result derived in
the Appendix of our paper (arXiv:1310.2185), namely, that "there are no
tachyonic (i.e., unstable) modes for minimally coupled scalar fields in
asymptotically flat spherically symmetric static spacetimes containing no
horizons" is indeed correct.


title: Fundamental Limits of Nonintrusive Load Monitoring

abstract:
  Provided an arbitrary nonintrusive load monitoring (NILM) algorithm, we seek
bounds on the probability of distinguishing between scenarios, given an
aggregate power consumption signal. We introduce a framework for studying a
general NILM algorithm, and analyze the theory in the general case. Then, we
specialize to the case where the error is Gaussian. In both cases, we are able
to derive upper bounds on the probability of distinguishing scenarios. Finally,
we apply the results to real data to derive bounds on the probability of
distinguishing between scenarios as a function of the measurement noise, the
sampling rate, and the device usage.


title: Algebraic analysis of linear systems with double type of perturbations

abstract:
  Linear systems under the influence of nonlinear and random linear
perturbations, and with random initial and boundary conditions, are discussed.
The notion of states of a system is substituted by the notion of the generating
vectors for n-point information (n-pi), n=0,1,2,..., characterizing a system at
different space-time points. A complete system of equations for physical n-pi
are derived and certain universal expansions are proposed.


title: Conditional Entropy based User Selection for Multiuser MIMO Systems

abstract:
  We consider the problem of user subset selection for maximizing the sum rate
of downlink multi-user MIMO systems. The brute-force search for the optimal
user set becomes impractical as the total number of users in a cell increase.
We propose a user selection algorithm based on conditional differential
entropy. We apply the proposed algorithm on Block diagonalization scheme.
Simulation results show that the proposed conditional entropy based algorithm
offers better alternatives than the existing user selection algorithms.
Furthermore, in terms of sum rate, the solution obtained by the proposed
algorithm turns out to be close to the optimal solution with significantly
lower computational complexity than brute-force search.


title:
The dynamical behaviour of a jet in an on-disk coronal hole observed
  with AIA/SDO

abstract:
  EUV jets situated in coronal holes are thought to play an important role in
supplying heated material to the corona and solar wind. The multi-wavelength
capabilities and high signal-to-noise of detectors on-board SDO allows for
detailed study of these jet's evolution. We aim to exploit SDO's capabilities
to reveal information on the jet dynamics and obtain estimates for plasma
properties associated with the jet. We study the dynamics an EUV jet with
AIA/SDO at a coronal hole boundary. The details of the jet evolution are
discussed and measurements of the jet's parameters, e.g. length, width, life
time, outward speed, are obtained. Further, automated emission measure analysis
is exploited to determine estimates for the temperature and density of the jet.
A propagating transverse wave supported by the jet spire is also observed.
Measurement of the wave properties are exploited for magneto-seismology and are
used in conjunction with the emission measure results to estimate the magnetic
field strength of the jet. We present a detailed description of the jet's
evolution, with new evidence for plasma flows, prior to the jet's initiation,
along the loops at the base of the jet and also find further evidence that
flows along the jet spire consist of multiple, quasi-periodic small-scale
plasma ejection events. In addition, DEM analysis suggests that the jet has
temperatures of $\log{5.89\pm0.08}$ K and electron densities of
$\log{8.75\pm0.05}$ cm$^{-3}$. Measured properties of the transverse wave
suggest the wave is heavily damped as it propagates along the jet spire with
speeds of $\sim110$ km/s. The magneto-seismological inversion of the wave
parameters provides values of $B=1.21\pm0.2$ G along the jet spire, which is in
line with previous estimates for open fields in coronal holes.}


title:
Classical and Quantum Transport in One-Dimensional Periodically Kicked
  Systems

abstract:
  This paper is a brief review of classical and quantum transport phenomena, as
well as related spectral properties, exhibited by one-dimensional periodically
kicked systems. Two representative and fundamentally different classes of
systems will be considered, those satisfying the classical
Kolmogorov-Arnol'd-Moser scenario and those which not. The experimental
realization of some of these systems using atom-optics methods will be
mentioned.


title: A comparison of bandwidth selectors for mean shift clustering

abstract:
  We explore the performance of several automatic bandwidth selectors,
originally designed for density gradient estimation, as data-based procedures
for nonparametric, modal clustering. The key tool to obtain a clustering from
density gradient estimators is the mean shift algorithm, which allows to obtain
a partition not only of the data sample, but also of the whole space. The
results of our simulation study suggest that most of the methods considered
here, like cross validation and plug in bandwidth selectors, are useful for
cluster analysis via the mean shift algorithm.


title:
Ultrarelativistic electron states in a general background
  electromagnetic field

abstract:
  The feasibility of obtaining exact analytical results in the realm of QED in
the presence of a background electromagnetic field is almost exclusively
limited to a few tractable cases, where the Dirac equation in the corresponding
background field can be solved analytically. This circumstance has restricted,
in particular, the theoretical analysis of QED processes in intense laser
fields to within the plane-wave approximation even at those high intensities,
achievable experimentally only by tightly focusing the laser energy in space.
Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we
construct analytically single-particle electron states in the presence of a
background electromagnetic field of general space-time structure in the
realistic assumption that the initial energy of the electron is the largest
dynamical energy scale in the problem. The relatively compact expression of
these states opens, in particular, the possibility of investigating
analytically strong-field QED processes in the presence of spatially focused
laser beams, which is of particular relevance in view of the upcoming
experimental campaigns in this field.


title: Sticky continuous processes have consistent price systems

abstract:
  Under proportional transaction costs, a price process is said to have a
consistent price system, if there is a semimartingale with an equivalent
martingale measure that evolves within the bid-ask spread. We show that a
continuous, multi-asset price process has a consistent price system, under
arbitrarily small proportional transaction costs, if it satisfies a natural
multi-dimensional generalization of the stickiness condition introduced by
Guasoni [Math. Finance 16(3), 569-582 (2006)].


title: Neutrino oscillations

abstract:
  In the last decades, a very important breakthrough has been brought in the
elementary particle physics by the discovery of the phenomenon of the neutrino
oscillations, which has shown neutrino properties beyond the Standard Model.
But a full understanding of the various aspects of the neutrino oscillations is
far to be achieved. In this paper the theoretical background of the neutrino
oscillation phenomenon is described, referring in particular to the
paradigmatic models. Then the various techniques and detectors which studied
neutrinos from different sources are discussed, starting from the pioneering
ones up to the detectors still in operation and to those in preparation. The
physics results are finally presented adopting the same research path which has
crossed this long saga. The problems not yet fixed in this field are discussed,
together with the perspectives of their solutions in the near future.


title:
Search for $t\bar{t}$ resonances in semileptonic final states in pp
  collisions at $\sqrt{s}$ = 8 TeV

abstract:
  A search for the production of new heavy resonances produced in proton-proton
collisions at the CMS Experiment that decay into top quark pairs is presented.
Data was recorded at a center of mass energy of 8 TeV and corresponds to an
integrated luminosity of 19.6 fb$^{-1}$. Results are presented as a combination
of two dedicated searches, the first optimized for kinematic threshold
production of top quark pairs and the second optimized for a highly boosted
regime. No excess is observed above the expected yield from SM processes. In
the absence of any excess we set the following limits at 95% CL on the
production of non-SM particles. Top color Z' bosons with relative widths of
1.2% and 10% are excluded for masses below 2.10 TeV and 2.68 TeV. Upper limits
of 1.94 pb and 0.029 pb are set on the production cross section times branching
fraction for narrow resonances with masses of 0.5 TeV and 2 TeV. Likewise,
limits of 1.71 pb and 0.045 pb are set for wide resonances with masses of 0.5
TeV and 2 TeV. In addition, Kaluza-Klein excitations of a gluon with masses
below 2.54 TeV in the Randall-Sundrum model are excluded and an upper limit of
0.101 pb is set for a resonance mass of 2 TeV.


title:
High-resolution measurements of the spatial and temporal evolution of
  megagauss magnetic fields created in intense short-pulse laser-plasma
  interactions

abstract:
  A pump-probe polarimetric technique is demonstrated, which provides a
complete, temporally and spatially-resolved mapping of the megagauss magnetic
fields generated in intense short-pulse laser-plasma interactions. A
normally-incident time-delayed probe pulse reflected from its critical surface
undergoes a change in its ellipticity according to the magneto-optic
Cotton-Mouton effect due to the azimuthal nature of the ambient self-generated
megagauss magnetic fields. The temporal resolution of the magnetic field
mapping is of the order of the pulsewidth, whereas a spatial resolution of a
few microns is achieved by this optical technique. In addition, this technique
does not suffer from refraction effects due to the steep plasma density
gradients owing to the near-normal incidence of the probe pulse and
consequently, higher harmonics of the probe can be employed to penetrate deeper
into the plasma to even near-solid densities. The spatial and temporal
evolution of the megagauss magnetic fields at the target front as well as at
the target rear are presented. The micron-scale resolution of the magnetic
field mapping provides valuable information on the filamentary instabilities at
the target front, whereas probing the target rear mirrors the highly complex
fast electron transport in intense laser-plasma interactions.


title:
Hi-fi phenomenological description of eclipsing binary light variations
  as the basis for their period analysis

abstract:
  In-depth analysis of eclipsing binary (EB) observational data collected for
several decades can inform us about a lot of astrophysically interesting
processes taking place in the systems. We have developed a wide-ranging method
for the phenomenological modelling of eclipsing binary phase curves that
enables us to combine even very disparate sources of phase information. This
approach is appropriate for the processing of both standard photometric series
of eclipses and data from photometric surveys of all kind. We conclude that
mid-eclipse times, determined using the latest version of our 'hi-fi'
phenomenological light curve models, as well as their accuracy, are nearly the
same as the values obtained using much more complex standard physical EB
models.


title: A Heavy "Neutralino" in Warped Extra dimensions

abstract:
  Generic extensions of the Standard Model that respect baryon and lepton
numbers have accidentally stable particles. Typical examples are the lightest
exotic neutral fermion, or "neutralino", and fields with non-trivial lepton and
baryon charges. In this paper we show that an accidentally stable neutralino is
a natural dark matter candidate in models with warped extra dimensions. We find
that annihilation into other Kaluza-Klein resonances is often allowed and very
efficient. The observed dark matter abundance may then be obtained with
couplings of order unity and a compactification scale above the TeV. Light dark
matter is also possible in the presence of unsuppressed couplings to the Higgs
boson. In this latter case direct detection experiments will soon be able to
probe a significant portion of the parameter space.


title: L\'imites directos de prolongaciones de algebroides de Lie

abstract:
  We prove that direct limits of finite dimensional Lie algebroids and their
prolongations can be endowed with structures of convenient spaces.


title:
Linear bounds for Calder\'{o}n-Zygmund operators with even kernel on UMD
  spaces

abstract:
  It is well-known that several classical results about Calder\'{o}n-Zygmund
singular integral operators can be extended to \(X\)-valued functions if and
only if the Banach space \(X\) has the UMD property. The dependence of the norm
of an \(X\)-valued Calder\'{o}n-Zygmund operator on the UMD constant of the
space \(X\) is conjectured to be linear. We prove that this is indeed the case
for sufficiently smooth Calder\'{o}n-Zygmund operators with cancellation,
associated to an even kernel. Our method uses the Bellman function technique to
obtain the right estimates for the norm of dyadic Haar shift operators. We then
apply the representation theorem of T. Hyt\"{o}nen to extend the result to
general Calder\'{o}n-Zygmund operators.


title:
BACOM 2.0 facilitates absolute normalization and quantification of
  somatic copy number alterations in heterogeneous tumor

abstract:
  BACOM is a statistically principled and unsupervised method that detects copy
number deletion types (homozygous versus heterozygous), estimates normal cell
fraction, and recovers cancer specific copy number profiles, using allele
specific copy number signals. In a subsequent analysis of TCGA ovarian cancer
dataset, the average normal cell fraction estimated by BACOM was found higher
than expected. In this letter, we first discuss the advantages of the BACOM in
relation to alternative approaches. Then, we show that this elevated estimate
of normal cell fraction is the combined result of inaccurate signal modeling
and normalization. Lastly, we describe an allele specific signal modeling and
normalization scheme that can enhance BACOM applications in many biological
contexts. An open source MATLAB program was developed to implement our extended
method and it is publically available.


title:
The Plasma Simulation Code: A modern particle-in-cell code with
  load-balancing and GPU support

abstract:
  Recent increases in supercomputing power, driven by the multi-core revolution
and accelerators such as the IBM Cell processor, graphics processing units
(GPUs) and Intel's Many Integrated Core (MIC) technology have enabled kinetic
simulations of plasmas at unprecedented resolutions, but changing HPC
architectures also come with challenges for writing efficient numerical codes.
This paper describes the Plasma Simulation Code (PSC), an explicit,
electromagnetic particle-in-cell code with support for different order particle
shape functions. We focus on two distinguishing feature of the code:
patch-based load balancing using space-filling curves, and support for Nvidia
GPUs, which achieves substantial speed-up of up to more than 6x on the Cray XK7
architecture compared to a CPU-only implementation.


title: Multiple-time-scale Landau-Zener transitions in many-body systems

abstract:
  Motivated by recent cold atom experiments in optical lattices, we consider a
lattice version of the Landau-Zener problem. Every single site is described by
a Landau-Zener problem, but due to particle tunnelling between neighboring
lattice sites this onsite single particle Landau-Zener dynamics couples to the
particle motion within the lattice. The lattice, apart from having a dephasing
effect on single site Landau-Zener transitions, also implies, in the presence
of a confining trap, an inter-site particle flow induced by the Landau-Zener
sweeping. This gives rise to an interplay between intra- and inter-site
dynamics. The adiabaticity constrain is therefor not simply given by the
standard one; the Hamiltonian rate of change relative to the gap of the onsite
problem. In experimentally realistic situations, the full system evolution is
well described by Franck-Condon physics, e.g. non-adiabatic excitations are
predominantly external ones characterized by large phononic vibrations in the
atomic cloud, while internal excitations are very weak as close to perfect
onsite transitions take place.


title: Automatic Classification of Variable Stars in Catalogs with missing data

abstract:
  We present an automatic classification method for astronomical catalogs with
missing data. We use Bayesian networks, a probabilistic graphical model, that
allows us to perform inference to pre- dict missing values given observed data
and dependency relationships between variables. To learn a Bayesian network
from incomplete data, we use an iterative algorithm that utilises sampling
methods and expectation maximization to estimate the distributions and
probabilistic dependencies of variables from data with missing values. To test
our model we use three catalogs with missing data (SAGE, 2MASS and UBVI) and
one complete catalog (MACHO). We examine how classification accuracy changes
when information from missing data catalogs is included, how our method
compares to traditional missing data approaches and at what computational cost.
Integrating these catalogs with missing data we find that classification of
variable objects improves by few percent and by 15% for quasar detection while
keeping the computational cost the same.


title:
On the First Eigenfunction of the Symmetric Stable Process in a Bounded
  Lipschitz Domain

abstract:
  We give a proof that the first eigenfunction of the $\alpha$-symmetric stable
process on a bounded Lipschitz domain in $\R^d$, $d\geq 1$, is superharmonic
for $\alpha=2/m$, where $m>2$ is an integer. This result was first proved for
the ball by M. Ka{\ss}mann and L. Silvestre (personal communication) with
different methods. For $\alpha=1$, the result was proved in \cite[Theorem
4.7]{BanKul}.


title: NuSTAR and INTEGRAL observations of a low/hard state of 1E1740.7-2942

abstract:
  The microquasar 1E1740.7-2942, also known as the "Great Annihilator", was
observed by NuSTAR in the Summer of 2012. We have analyzed in detail two
observations taken ~2 weeks apart, for which we measure hard and smooth spectra
typical of the low/hard state. A few weeks later the source flux declined
significantly. Nearly simultaneous coverage by INTEGRAL is available from its
Galactic Center monitoring campaign lasting ~2.5 months. These data probe the
hard state spectrum from 1E1740.7-2942 before the flux decline. We find good
agreement between the spectra taken with IBIS/ISGRI and NuSTAR, with the
measurements being compatible with a change in flux with no spectral
variability. We present a detailed analysis of the NuSTAR spectral and timing
data and upper limits for reflection of the high energy emission. We show that
the high energy spectrum of this X-ray binary is well described by thermal
Comptonization.


title: Fibered Threefolds and Lang-Vojta's Conjecture over Function Fields

abstract:
  Using the techniques introduced by Corvaja and Zannier we solve the non-split
case of the geometric Lang-Vojta Conjecture for affine surfaces isomorphic to
the complement of a conic and two lines in the projective plane. In this
situation we deal with sections of an affine threefold fibered over a curve,
whose boundary, in the natural projective completion, is a quartic bundle over
the base whose fibers have three irreducible components. We prove that the
image of each section has bounded degree in terms of the Euler Characteristic
of the base curve.


title: A moment problem for random discrete measures

abstract:
  Let $X$ be a locally compact Polish space. A random measure on $X$ is a
probability measure on the space of all (nonnegative) Radon measures on $X$.
Denote by $\mathbb K(X)$ the cone of all Radon measures $\eta$ on $X$ which are
of the form $\eta=\sum_{i}s_i\delta_{x_i}$, where, for each $i$, $s_i>0$ and
$\delta_{x_i}$ is the Dirac measure at $x_i\in X$. A random discrete measure on
$X$ is a probability measure on $\mathbb K(X)$. The main result of the paper
states a necessary and sufficient condition (conditional upon a mild a priori
bound) when a random measure $\mu$ is also a random discrete measure. This
condition is formulated solely in terms of moments of the random measure $\mu$.
Classical examples of random discrete measures are completely random measures
and additive subordinators, however, the main result holds independently of any
independence property. As a corollary, a characterisation via a moments is
given when a random measure is a point process.


title: Lifting free divisors

abstract:
  Let $\varphi:X\to S$ be a morphism between smooth complex analytic spaces,
and let $f=0$ define a free divisor on $S$. We prove that if the deformation
space $T^1_{X/S}$ of $\varphi$ is a Cohen-Macaulay $\mathcal{O}_X$-module of
codimension 2, and all of the logarithmic vector fields for $f=0$ lift via
$\varphi$, then $f\circ \varphi=0$ defines a free divisor on $X$; this is
generalized in several directions.
  Among applications we recover a result of Mond-van Straten, generalize a
construction of Buchweitz-Conca, and show that a map
$\varphi:\mathbb{C}^{n+1}\to \mathbb{C}^n$ with critical set of codimension $2$
has a $T^1_{X/S}$ with the desired properties. Finally, if $X$ is a
representation of a reductive complex algebraic group $G$ and $\varphi$ is the
algebraic quotient $X\to S=X// G$ with $X// G$ smooth, we describe sufficient
conditions for $T^1_{X/S}$ to be Cohen-Macaulay of codimension $2$. In one such
case, a free divisor on $\mathbb{C}^{n+1}$ lifts under the operation of
"castling" to a free divisor on $\mathbb{C}^{n(n+1)}$, partially generalizing
work of Granger-Mond-Schulze on linear free divisors. We give several other
examples of such representations.


title:
Photoluminescence decay of silicon nanocrystals and L\'{e}vy stable
  distributions

abstract:
  Recent experiments have shown that photoluminescence decay of silicon
nanocrystals can be described by the stretched exponential function. We show
here that the associated decay probability rate is the one-sided Levy stable
distribution which describes well the experimental data. The relevance of these
conclusions to the underlying stochastic processes is discussed in terms of
Levy processes.


title: Partially twisted boundary conditions for scalar mesons

abstract:
  The possibility of imposing partially twisted boundary conditions in the
lattice study of the resonance states is investigated by using the effective
field theory (EFT) methods. In particular, it is demonstrated that - in certain
cases - it is possible to use partial twisting even in the presence of the
quark annihilation diagrams.


title:
Magnetic catalysis (and inverse catalysis) at finite temperature in
  two-color lattice QCD

abstract:
  Two-color lattice QCD with N_f=4 staggered fermion degrees of freedom (no
rooting trick is applied) with equal electric charge q is studied in a
homogeneous magnetic background field B and at non-zero temperature T. In order
to circumvent renormalization as a function of the bare coupling we apply a
fixed-scale approach. We study the influence of the magnetic field on the
critical temperature. At rather small pseudo-scalar meson mass ($m_{\pi}
\approx 175 \mathrm{MeV} \approx T_c(B=0)$) we confirm a monotonic rise of the
quark condensate $<\bar{\psi} \psi>$ with increasing magnetic field strength,
i.e. magnetic catalysis, as long as one is staying within the confinement or
deconfinement phase. In the transition region we find indications for a
non-monotonic behavior of $T_c(B)$ at low magnetic field strength ($qB<0.8
\mathrm{GeV}^2$) and a clear rise at stronger magnetic field. The conjectured
existence of a minimum value $T_c(B^{*}) < T_c(B=0)$ would leave a temperature
window for a decrease of $<\bar{\psi} \psi>$ with rising $B$ (inverse magnetic
catalysis) also in the present model.


title: Mixed braid group actions from deformations of surface singularities

abstract:
  We consider a set of toric Calabi-Yau varieties which arise as deformations
of the small resolutions of type A surface singularities. By careful analysis
of the heuristics of B-brane transport in the associated GLSMs, we predict the
existence of a mixed braid group action on the derived category of each
variety, and then prove that this action does indeed exist. This generalizes
the braid group action found by Seidel and Thomas for the undeformed
resolutions. We also show that the actions for different deformations are
related, in a way that is predicted by the physical heuristics.


title:
Radiatively induced symmetry breaking and the conformally coupled
  magnetic monopole in AdS space

abstract:
  We implement quantum corrections for a magnetic monopole in a classically
conformally invariant theory containing gravity. This yields the trace
(conformal) anomaly and introduces a length scale in a natural fashion via the
process of renormalization. We evaluate the one-loop effective potential and
extract the vacuum expectation value (VEV) from it; spontaneous symmetry
breaking is radiatively induced. The VEV is set at the renormalization scale
$M$ and we exchange the dimensionless scalar coupling constant for the
dimensionful VEV via dimensional transmutation. The asymptotic (background)
spacetime is anti-de Sitter (AdS) and its Ricci scalar is determined entirely
by the VEV. We obtain analytical asymptotic solutions to the coupled set of
equations governing gravitational, gauge and scalar fields that yield the
magnetic monopole in an AdS spacetime.


title:
FIRST, a fibered aperture masking instrument II. Spectroscopy of the
  Capella binary system at the diffraction limit

abstract:
  FIRST is a prototype instrument built to demonstrate the capabilities of the
pupil remapping technique, using single-mode fibers and working at visible
wavelengths. We report on observations of the binary system Capella at three
epochs over a period of 14 months with FIRST-18 (that recombines 2 sets of 9
fibers) mounted on the 3-m Shane telescope at Lick Observatory. The binary
separation during our observations ranges from 0.8 to 1.2 times the diffraction
limit of the telescope at the central wavelength. We successfully resolved the
Capella binary system with an astrometric precision as good as 1mas under the
best observing conditions. FIRST also gives access to the spectral flux ratio
between the two components directly measured with an unprecedented spectral
resolution (around 300) over the 600-850nm range. In particular, our data allow
to detect the well-known overall slope of the flux ratio spectrum, leading to
an estimation of the pivot wavelength of 0.64+/-0.01um, at which the cooler
component becomes the brightest. Spectral features arising from the difference
in effective temperature (specifically the Halpha line, TiO and CN bands) have
been used to constrain the stellar parameters. The effective temperatures we
derive for both components are slightly lower (5-7%) than the well-established
properties for this system. This difference mainly originates from deeper
molecular features than those predicted by state-of-the-art stellar atmospheric
models, suggesting that molecular line lists used in the photospheric models
are incomplete and/or oscillator strengths are underestimated (most likely
concerning the CN molecule). These results demonstrate the power of FIRST, a
fibered pupil remapping based instrument, in terms of high angular resolution
and show that the direct measurement of the spectral flux ratio provides
valuable information to characterize little known companions.


title:
Radial multipliers on arbitrary amalgamated free products of finite von
  Neumann algebras

abstract:
  Let $(M_i)_{i}$ be a (finite or infinite) family of finite von Neumann
algebras with a common subalgebra $P$. When $\varphi:\IN\rightarrow\IC$ is a
function, we define the radial multiplier $M_\varphi$ on the amalgamated free
product $M=M_1\free_P M_2\free_P\ldots$ setting $M_{\varphi}(x)=\varphi(n)x$
for every reduced expression $x$ of length $n$. In this paper we give a
sufficient condition on $\varphi$ to ensure that the corresponding radial
multiplier $M_\varphi$ is a completely bounded map, and moreover we give an
upper bound on its completely bounded norm. Our condition on $\varphi$ does not
depend on the choice of von Neumann algebras $(M_i)_i$ and $P$. This result
extends earlier results by Haagerup and M\"oller, who proved the same statement
for free products without amalgamation, and M\"oller showed that the same
statement holds when $P$ has finite index in each of the $M_i$.


title:
Unique Continuation for Fractional Schr\"odinger Equations with Rough
  Potential

abstract:
  This article deals with the weak and strong unique continuation principle for
fractional Schr\"odinger equations with scaling-critical and rough potentials
via Carleman estimates. Our methods allow to apply the results to variable
coefficient versions of fractional Schr\"odinger equations.


title: Localized Quantum States

abstract:
  Let X be a symplectic manifold and Aut(L) the automorphism group of a
Kostant-Souriau line bundle on X. *Quantum states for X*, as defined by J.-M.
Souriau in the 1990s, are certain positive-definite functions on Aut(L) or,
less ambitiously, on any "large enough" subgroup G of Aut(L). This definition
has two major drawbacks: when G=Aut(L) there are no known examples; and when G
is a Lie subgroup the notion is, as we shall see, far from selective enough. In
this paper we introduce the concept of a quantum state *localized at Y*, where
Y is a coadjoint orbit of a subgroup H of G. We show that such states exist,
and tend to be unique when Y has lagrangian preimage in X. This solves, in a
number of cases, A. Weinstein's "fundamental quantization problem" of attaching
state vectors to lagrangian submanifolds.


title: Global patterns of sex-biased migrations in humans

abstract:
  A series of studies have revealed the among-population components of genetic
variation are higher for the paternal Y chromosome than for the maternal
mitochondrial DNA (mtDNA), which indicates sex-biased migrations in human
populations. However, this phenomenon might be also an ascertainment bias due
to nonrandom sampling of SNPs. To eliminate the possible bias, we used the
whole Y chromosome and mtDNA sequence data of 491 individuals from the 1000
Genomes Project Phase I to address the sex-biased migration dispute. We found
that genetic differentiation between populations was higher for Y chromosome
than for the mtDNA at global scales. The migration rate of female might be
three times higher than that of male, assuming the effective population size is
the same for male and female.


title: Point-pushing in 3-manifolds

abstract: We study the Birman exact sequence for compact 3-manifolds.


title: Quantum Indeterminacy, Polar Duality, and Symplectic Capacities

abstract:
  The notion of polarity between sets, well-known from convex geometry, is a
geometric version of the Fourier transform. We exploit this analogy to propose
a new simple definition of quantum indeterminacy, using what we call
"hbar-polar quantum pairs", which can be viewed as pairs of position-momentum
indeterminacy with minimum spread. The existence of such pairs is guaranteed by
the usual uncertainty principle, but is at the same time more general. We use
recent advances in symplectic topology to show that this quantum indeterminacy
can be measured using a particular symplectic capacity related to action and
which reduces to area in the case of one degree of freedom. We show in addition
that polar quantum pairs are closely related to Hardy's uncertainty principle
about the localization of a function and its Fourier transform.