title: Crafting Adversarial Input Sequences for Recurrent Neural Networks

abstract:
  Machine learning models are frequently used to solve complex security
problems, as well as to make decisions in sensitive situations like guiding
autonomous vehicles or predicting financial market behaviors. Previous efforts
have shown that numerous machine learning models were vulnerable to adversarial
manipulations of their inputs taking the form of adversarial samples. Such
inputs are crafted by adding carefully selected perturbations to legitimate
inputs so as to force the machine learning model to misbehave, for instance by
outputting a wrong class if the machine learning task of interest is
classification. In fact, to the best of our knowledge, all previous work on
adversarial samples crafting for neural network considered models used to solve
classification tasks, most frequently in computer vision applications. In this
paper, we contribute to the field of adversarial machine learning by
investigating adversarial input sequences for recurrent neural networks
processing sequential data. We show that the classes of algorithms introduced
previously to craft adversarial samples misclassified by feed-forward neural
networks can be adapted to recurrent neural networks. In a experiment, we show
that adversaries can craft adversarial sequences misleading both categorical
and sequential recurrent neural networks.


title: Stochastic Komatu-Loewner evolutions and SLEs

abstract:
  Let $D={\mathbb H}\setminus \bigcup_{j=1}^N C_j$ be a standard slit domain,
where ${\mathbb H}$ is the upper half plane and $C_j,1\le j\le N,$ are mutually
disjoint horizontal line segments in ${\mathbb H}$. A stochastic Komatu-Loewner
evolution denoted by ${\rm SKLE}_{\alpha,b}$ has been introduced in \cite{CF}
as a family $\{F_t\}$ of random growing hulls with $F_t\subset D$ driven by a
diffusion process $\xi(t)$ on $\partial {\mathbb H}$ that is determined by
certain continuous homogeneous functions $\alpha$ and $b$ defined on the space
${\cal S}$ of all labelled standard slit domains. We aim at identifying the
distribution of a suitably reparametrized ${\rm SKLE}_{\alpha,b}$ with that of
the Loewner evolution on ${\mathbb H}$ driven by the path of a certain
continuous semimartingale and thereby relating the former to the distribution
of ${\rm SLE}_{\alpha^2}$ when $\alpha$ is a constant. We then prove that, when
$\alpha$ is a constant, ${\rm SKLE}_{\alpha,b}$ up to some random hitting time
and modulo a time change has the same distribution as ${\rm SLE}_{\alpha^2}$
under a suitable Girsanov transformation. We further show that a reparametrized
${\rm SKLE}_{\sqrt{6},-b_{\rm BMD}}$ has the same distribution as ${\rm
SLE}_6$, where $b_{\rm BMD}$ is the BMD-domain constant indicating the
discrepancy of $D$ from ${\mathbb H}$ relative to Brownian motion with darning
(BMD in abbreviation). A key ingredient of the proof is a hitting time analysis
for the absorbing Brownian motion on ${\mathbb H}.$ We also revisit and examine
the locality property of ${\rm SLE}_6$ in several canonical domains. Finally
K-L equations and SKLEs for other canonical multiply connected planar domains
than the standard slit one are recalled and examined.


title:
Vanishing ranges for the mod $p$ cohomology of alternating subgroups of
  Coxeter groups

abstract:
  We obtain vanishing ranges for the mod $p$ cohomology of alternating
subgroups of finite $p$-free Coxeter groups. Here a Coxeter group $W$ is
$p$-free if the order of the product $st$ is prime to $p$ for every pair of
Coxeter generators $s,t$ of $W$. Our result generalizes those for alternating
groups formerly proved by Kleshchev-Nakano and Burichenko. As a byproduct, we
obtain vanishing ranges for the twisted cohomology of finite $p$-free Coxeter
groups with coefficients in the sign representations. In addition, a weak
version of the main result is proved for a certain class of infinite Coxeter
groups.


title:
Salt Effects on the Thermodynamics of a Frameshifting RNA Pseudoknot
  under Tension

abstract:
  Because of the potential link between -1 programmed ribosomal frameshifting
and response of a pseudoknot (PK) RNA to force, a number of single molecule
pulling experiments have been performed on PKs to decipher the mechanism of
programmed ribosomal frameshifting. Motivated in part by these experiments, we
performed simulations using a coarse-grained model of RNA to describe the
response of a PK over a range of mechanical forces ($f$s) and monovalent salt
concentrations ($C$s). The coarse-grained simulations quantitatively reproduce
the multistep thermal melting observed in experiments, thus validating our
model. The free energy changes obtained in simulations are in excellent
agreement with experiments. By varying $f$ and $C$, we calculated the phase
diagram that shows a sequence of structural transitions, populating distinct
intermediate states. As $f$ and $C$ are changed, the stem-loop tertiary
interactions rupture first, followed by unfolding of the $3^{\prime}$-end
hairpin ($\textrm{I}\rightleftharpoons\textrm{F}$). Finally, the
$5^{\prime}$-end hairpin unravels, producing an extended state
($\textrm{E}\rightleftharpoons\textrm{I}$). A theoretical analysis of the phase
boundaries shows that the critical force for rupture scales as $\left(\log
C_{\textrm{m}}\right)^{\alpha}$ with $\alpha=1\,(0.5)$ for
$\textrm{E}\rightleftharpoons\textrm{I}$
($\textrm{I}\rightleftharpoons\textrm{F}$) transition. This relation is used to
obtain the preferential ion-RNA interaction coefficient, which can be
quantitatively measured in single-molecule experiments, as done previously for
DNA hairpins. A by-product of our work is the suggestion that the frameshift
efficiency is likely determined by the stability of the $5^{\prime}$-end
hairpin that the ribosome first encounters during translation.

categories: q-bio.BM cond-mat.soft physics.bio-ph physics.chem-ph


title: Hypotheses for near-surface exchange of methane on Mars

abstract:
  The Curiosity rover recently detected a background of 0.7 ppb and spikes of 7
ppb of methane on Mars. This in situ measurement reorients our understanding of
the Martian environment and its potential for life, as the current theories do
not entail any geological source or sink of methane that varies sub-annually.
In particular, the 10-fold elevation during the southern winter indicates
episodic sources of methane that are yet to be discovered. Here we suggest a
near-surface reservoir could explain this variability. Using the temperature
and humidity measurements from the rover, we find that perchlorate salts in the
regolith deliquesce to form liquid solutions, and deliquescence progresses to
deeper subsurface in the season of the methane spikes. We therefore formulate
the following three testable hypotheses. The first scenario is that the
regolith in Gale Crater adsorbs methane when dry and releases this methane to
the atmosphere upon deliquescence. The adsorption energy needs to be 36 kJ/mol
to explain the magnitude of the methane spikes, higher than existing laboratory
measurements. The second scenario is that microorganisms convert organic matter
in the soil to methane when they are in liquid solutions. This scenario does
not require regolith adsorption, but entails extant life on Mars. The third
scenario is that deep subsurface aquifers produce the bursts of methane.
Continued in situ measurements of methane and water, as well as laboratory
studies of adsorption and deliquescence, will test these hypotheses and inform
the existence of the near-surface reservoir and its exchange with the
atmosphere.


title: Universal Symmetry-Protected Resonances in a Spinful Luttinger Liquid

abstract:
  We study the problem of resonant tunneling through a quantum dot in a spinful
Luttinger liquid. For a range of repulsive interactions, we find that for
symmetric barriers there exist resonances with a universal peak conductance
$2g^* e^2/h$ that are controlled by a non-trivial intermediate fixed point.
This fixed point is also a quantum critical point separating symmetry-protected
topological phases. By tuning the system through resonance, all SPT phases can
be accessed. For a particular interaction strength with Luttinger parameters
$g_\rho=1/3$ and $g_\sigma=1$, we show that the problem is equivalent to a two
channel $SU(3)$ Kondo problem($SU(3)_2$ CFT). At the Toulouse limit, both
problems can be mapped to a quantum Brownian motion model on a Kagome lattice,
which in turn is related to the quantum Brownian motion on a honeycomb lattice
and the three-channel $SU(2)$ Kondo problem($SU(2)_3$ CFT). "Level-rank
duality" in the quantum Brownian motion model relating $SU(2)_k$ CFT to
$SU(k)_2$ CFT is also explored. Utilizing the boundary conformal field theory,
the on-resonance conductance of our resonant tunneling problem is calculated as
well as the scaling dimension of the leading relevant operator. This allows us
to compute the scaling behavior of the resonance line-shape as a function of
temperature.


title:
Violation of Cluster Decomposition and Absence of Light-Cones in Local
  Integer and Half-Integer Spin Chains

abstract:
  We compute the ground state correlation functions of an exactly solvable
chain of integer spins, recently introduced in [R. Movassagh and P. W. Shor,
arXiv:1408.1657], whose ground-state can be expressed in terms of a uniform
superposition of all colored Motzkin paths. Our analytical results show that
for spin s$\ge$2 there is a violation of the cluster decomposition property.
This has to be contrasted with s=1, where the cluster property holds.
Correspondingly, for s=1 one gets a light-cone profile in the propagation of
excitations after a local quench, while the cone is absent for s=2, as shown by
time dependent density-matrix-renormalization-group. Moreover, we introduce an
original solvable model of half-integer spins which we refer to as Fredkin spin
chain, whose ground-state can be expressed in terms of superposition of all
Dyck paths. For this model we exactly calculate the magnetization and
correlation functions, finding that for s=1/2, a cone-like propagation occurs
while for higher spins, s$\ge$3/2, the colors prevent any cone formation and
clustering is violated, together with square root deviation from the area law
for the entanglement entropy.

categories: cond-mat.str-el cond-mat.stat-mech math-ph math.MP quant-ph


title: AdS and Lifshitz Scalar Hairy Black Holes in Gauss-Bonnet Gravity

abstract:
  We consider Gauss-Bonnet (GB) gravity in general dimensions, which is
non-minimally coupled to a scalar field. By choosing the scalar potential of
the type $V(\phi)=2\Lambda_0+\fft 12m^2\phi^2+\gamma_4\phi^4$, we first obtain
large classes of scalar hairy black holes with spherical/hyperbolic/planar
topologies that are asymptotic to locally anti-de Sitter (AdS) space-times. We
derive the first law of black hole thermodynamics using Wald formalism. In
particular, for one class of the solutions, the scalar hair forms a
thermodynamic conjugate with the graviton and nontrivially contributes to the
thermodynamical first law. We observe that except for one class of the planar
black holes, all these solutions are constructed at the critical point of GB
gravity where there exists an unique AdS vacua. In fact, Lifshitz vacuum is
also allowed at the critical point. We then construct many new classes of
neutral and charged Lifshitz black hole solutions for a either minimally or
non-minimally coupled scalar and derive the thermodynamical first laws. We also
obtain new classes of exact dynamical AdS and Lifshitz solutions which describe
radiating white holes. The solutions eventually become an AdS or Lifshitz vacua
at late retarded times. However, for one class of the solutions the final state
is an AdS space-time with a globally naked singularity.


title: Period mappings for noncommutative algebras

abstract:
  We construct a period mapping for deformations of a differential graded
algebra, that generalizes Griffiths' period mapping. It is constructed as a
morphism between differential graded Lie algebras which has a moduli-theoretic
interpretation, where the domain of the morphism is the shifted Hochschild
cocohain complex. We then use this period mapping to give some applications
such as unobstructedness of deformations.


title:
Talk&Learn: Improving Conversation Experience and Creating Opportunities
  for Foreign Language Learning

abstract:
  Existing Real-Time Translation Interfaces (RTTI) do not provide experience as
natural and efficient as monolingual communication. Also, such systems do not
provide functions supporting language learning. This results in the waste of
both time and potential language context. In order to overcome the above
limitations, we propose a solution named "Talk&Learn". Its core idea is to
rearrange ("Delay-Match") the real-time videos and translated texts or
speeches, so as to gain better naturalness and efficiency. At the same time,
this will create extra free time for users. So we further propose to utilize
the free time for contextual language learning.


title:
Estimate of the radius responsible for quasinormal modes in the extreme
  Kerr limit and asymptotic behavior of the Sasaki-Nakamura transformation

abstract:
  The Sasaki-Nakamura transformation gives a short-ranged potential and a
convergent source term for the master equation of perturbations in the Kerr
space-time. In this paper, we study the asymptotic behavior of the
transformation, and present a new relaxed necessary and sufficient condition of
the transformation to obtain the short-ranged potential in the assumption that
the transformation converges in the far distance. Also, we discuss quasinormal
mode frequencies which are determined by the information around the peak of the
potential in the WKB analysis. Finally, in the extreme Kerr limit, $a/M \to 1$,
where $M$ and $a$ denote the mass and spin parameter of a Kerr black hole,
respectively, we find the peak location of the potential, $r_p/M \lesssim 1 +
1.8 \,(1-a/M)^{1/2}$ by using the new transformation. The uncertainty of the
location is as large as that expected from the equivalence principle.


title:
Polarization measurements of hot dust stars and the local interstellar
  medium

abstract:
  Debris discs are typically revealed through excess emission at infrared
wavelengths. Most discs exhibit excess at mid- and far-infrared wavelengths,
analogous to the solar system's Asteroid and Edgeworth-Kuiper belts. Recently,
stars with strong (1 per cent) excess at near-infrared wavelengths were
identified through interferometric measurements. Using the HIgh Precision
Polarimetric Instrument (HIPPI), we examined a sub-sample of these hot dust
stars (and appropriate controls) at parts-per-million sensitivity in SDSS g'
(green) and r' (red) filters for evidence of scattered light. No detection of
strongly polarized emission from the hot dust stars is seen. We therefore rule
out scattered light from a normal debris disk as the origin of this emission. A
wavelength dependent contribution from multiple dust components for hot dust
stars is inferred from the dispersion (difference in polarization angle in red
and green) of southern stars. Contributions of 17 ppm (green) and 30 ppm (red)
are calculated, with strict 3 sigma upper limits of 76 and 68 ppm,
respectively. This suggests weak hot dust excesses consistent with thermal
emission, although we cannot rule out contrived scenarios, e.g. dust in a
spherical shell or face on discs. We also report on the nature of the local
interstellar medium, obtained as a byproduct of the control measurements.
Highlights include the first measurements of the polarimetric colour of the
local interstellar medium and discovery of a southern sky region with a
polarization per distance thrice the previous maximum. The data suggest the
wavelength of maximum polarization is bluer than typical.


title: Scaling limits for a family of unrooted trees

abstract:
  We introduce weights on the unrooted unlabelled plane trees as follows: let
$\mu$ be a probability measure on the set of nonnegative integers whose mean is
no larger than $1$; then the $\mu$-weight of a plane tree $t$ is defined as
$\Pi \, \mu (degree (v) -1)$, where the product is over the set of vertices $v$
of $t$. We study the random plane tree with a fixed diameter $p$ sampled
according to probabilities proportional to these $\mu$-weights and we prove
that, under the assumption that the sequence of laws $\mu_p$, $p\! \geq \! 1$,
belongs to the domain of attraction of an infinitely divisible law, the scaling
limits of such random plane trees are random compact real trees called the
unrooted Levy trees, which have been introduced in Duquense & Wang.


title:
Large-scale Ising spin network based on degenerate optical parametric
  oscillators

abstract:
  Simulating a network of Ising spins with physical systems is now emerging as
a promising approach for solving mathematically intractable problems. Here we
report a large-scale network of artificial spins based on degenerate optical
parametric oscillators (DOPO), paving the way towards a photonic Ising machine
capable of solving difficult combinatorial optimization problems. We generated
>10,000 time-division-multiplexed DOPOs using dual-pump four-wave mixing (FWM)
in a highly nonlinear fibre (HNLF) placed in a fibre cavity. Using those DOPOs,
a one-dimensional (1D) Ising model was simulated by introducing
nearest-neighbour optical coupling. We observed the formation of spin domains
and found that the domain size diverged near the DOPO threshold, which suggests
that the DOPO network can simulate the behavior of low-temperature Ising spins.


title:
Construction of quantum states with special properties by projection
  methods

abstract:
  We use projection methods to construct (global) quantum states with
prescribed reduced (marginal) states, and possibly with some special properties
such as having specific eigenvalues, having specific rank and extreme von
Neumann or Renyi entropy. Using convex analysis, optimization techniques on
matrix manifolds, we obtain algorithms to solve the problem. Matlab programs
are written based on these algorithms and numerical examples are illustrated.
The numerical results reveal new patterns leading to new insights and research
problems on the topic.


title: Chirality-driven Hall Transport Phenomena of Spins

abstract:
  Experimental and theoretical aspects of Hall-type transport of spins in
magnetic insulators are reviewed, with emphasis on their spin chirality origin.
A general formalism for linear response theory of thermal Hall transport in the
spin model is developed, which can be applied to both the magnon and the
paramagnetic, spin-liquid regimes. Recent experiments on magnon-mediated
thermal Hall transport in the two-dimensional kagome, and three-dimensional
pyrochlore ferromagnetic insulators are reviewed in light of the multi-band
magnon theory of Hall transport, and compared to the more mysterious thermal
Hall transport found in the putative quantum spin ice material. As realizations
of spin-chirality driven magnon transport in the real space, we review the
general theory of emergent gauge fields governing the magnon dynamics in the
textured magnet, and discuss its application to the magnon-Skyrmion scattering
problem. Topological magnon Hall effect driven by the Skyrmion texture is
discussed.


title: Streaming View Learning

abstract:
  An underlying assumption in conventional multi-view learning algorithms is
that all views can be simultaneously accessed. However, due to various factors
when collecting and pre-processing data from different views, the streaming
view setting, in which views arrive in a streaming manner, is becoming more
common. By assuming that the subspaces of a multi-view model trained over past
views are stable, here we fine tune their combination weights such that the
well-trained multi-view model is compatible with new views. This largely
overcomes the burden of learning new view functions and updating past view
functions. We theoretically examine convergence issues and the influence of
streaming views in the proposed algorithm. Experimental results on real-world
datasets suggest that studying the streaming views problem in multi-view
learning is significant and that the proposed algorithm can effectively handle
streaming views in different applications.


title:
Position-sensitive detection of ultracold neutrons with an imaging
  camera and its implications to spectroscopy

abstract:
  Position-sensitive detection of ultracold neutrons (UCNs) is demonstrated
using an imaging charge-coupled device (CCD) camera. A spatial resolution less
than 15 $\mu$m has been achieved, which is equivalent to an UCN energy
resolution below 2 pico-electron-volts through the relation $\delta E = m_0g
\delta x$. Here, the symbols $\delta E$, $\delta x$, $m_0$ and $g$ are the
energy resolution, the spatial resolution, the neutron rest mass and the
gravitational acceleration, respectively. A multilayer surface convertor
described previously is used to capture UCNs and then emits visible light for
CCD imaging. Particle identification and noise rejection are discussed through
the use of light intensity profile analysis. This method allows different types
of UCN spectroscopy and other applications.


title:
Pressure induced re-emergence of superconductivity in superconducting
  topological insulator Sr0.065Bi2Se3

abstract:
  The recent-discovered Sr$_x$Bi$_2$Se$_3$ superconductor provides an
alternative and ideal material base for investigating possible topological
superconductivity. Here, we report that in Sr$_{0.065}$Bi$_{2}$Se$_3$, the
ambient superconducting phase is gradually depressed upon the application of
external pressure. At high pressure, a second superconducting phase emerges at
above 6 GPa, with a maximum $T_c$ value of $\sim$8.3 K. The joint
investigations of the high-pressure synchrotron x-ray diffraction and
electrical transport properties reveal that the re-emergence of
superconductivity in Sr$_{0.065}$Bi$_{2}$Se$_3$ is closely related to the
structural phase transition from ambient rhombohedral phase to high-pressure
monoclinic phase around 6 GPa, and further to another high-pressure tetragonal
phase above 25 GPa.


title:
An Adaptive-to-Model Test for Parametric Single-Index
  Errors-in-Variables Models

abstract:
  This paper provides some useful tests for fitting a parametric single-index
regression model when covariates are measured with error and validation data is
available. We propose two tests whose consistency rates do not depend on the
dimension of the covariate vector when an adaptive-to-model strategy is
applied. One of these tests has a bias term that becomes arbitrarily large with
increasing sample size but its asymptotic variance is smaller, and the other is
asymptotically unbiased with larger asymptotic variance. Compared with the
existing local smoothing tests, the new tests behave like a classical local
smoothing test with only one covariate, and still are omnibus against general
alternatives. This avoids the difficulty associated with the curse of
dimensionality. Further, a systematic study is conducted to give an insight on
the effect of the values of the ratio between the sample size and the size of
validation data on the asymptotic behavior of these tests. Simulations are
conducted to examine the performance in several finite sample scenarios.


title:
Eigenpairs of Toeplitz and disordered Toeplitz matrices with a
  Fisher-Hartwig symbol

abstract:
  Toeplitz matrices have entries that are constant along diagonals. They model
directed transport, are at the heart of correlation function calculations of
the two-dimensional Ising model, and have applications in quantum information
science. We derive their eigenvalues and eigenvectors when the symbol is
singular Fisher-Hartwig. We then add diagonal disorder and study the resulting
eigenpairs. We find that there is a "bulk" behavior that is well captured by
second order perturbation theory of non-Hermitian matrices. The
non-perturbative behavior is classified into two classes: Runaways type I leave
the complex-valued spectrum and become completely real because of eigenvalue
attraction. Runaways type II leave the bulk and move very rapidly in response
to perturbations. These have high condition numbers and can be predicted.
Localization of the eigenvectors are then quantified using entropies and
inverse participation ratios . Eigenvectors corresponding to Runaways type II
are most localized (i.e., super-exponential), whereas Runaways type I are less
localized than the unperturbed counterparts and have most of their probability
mass in the interior with algebraic decays. The results are corroborated by
applying free probability theory and various other supporting numerical
studies.

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


title: Holographic Picture of Heavy Vector Meson Melting

abstract:
  The fraction of heavy vector mesons produced in a heavy ion collision, as
compared to a proton proton collision, serves as an important indication of the
formation of a thermal medium, the quark gluon plasma. This sort of analysis
strongly depends on understanding the thermal effects of a medium like the
plasma on the states of heavy mesons. In particular, it is crucial to know the
temperature ranges where they undergo a thermal dissociation, or melting.
AdS/QCD models are know to provide an important tool for the calculation of
hadronic masses, but in general are not consistent with the observation that
decay constants of heavy vector mesons decrease with excitation level. It has
recently been shown that this problem can be overcome using a soft wall
background and introducing an extra energy parameter, through the calculation
of correlation functions at a finite position of anti-de Sitter space. This
approach leads to the evaluation of masses and decay constants of S wave
quarkonium states with just one flavor dependent and one flavor independent
parameters. Here we extend this more realistic model to finite temperatures and
analyse the thermal behavior of the states $1S, 2S$ and $ 3S$ of bottomonium
and charmonium. The corresponding spectral function exhibits a consistent
picture for the melting of the states where, for each flavor, the higher
excitations melt at lower temperatures. We estimate for these six states, the
energy ranges in which the heavy vector mesons undergo a transition from a well
defined peak in the spectral function to complete melting in the thermal
medium. A very clear distinction between the heavy flavors emerges, with
bottomonium state $\Upsilon (1S)$ surviving deconfinemet transition at
temperatures much larger than the critical deconfinement temperature of the
medium.


title:
Collective, Coherent, and Ultrastrong Coupling of 2D Electrons with
  Terahertz Cavity Photons

abstract:
  Nonperturbative coupling of light with condensed matter in an optical cavity
is expected to reveal a host of coherent many-body phenomena and states. In
addition, strong coherent light-matter interaction in a solid-state environment
is of great interest to emerging quantum-based technologies. However, creating
a system that combines a long electronic coherence time, a large dipole moment,
and a high cavity quality ($Q$) factor has been a challenging goal. Here, we
report collective ultrastrong light-matter coupling in an ultrahigh-mobility
two-dimensional electron gas in a high-$Q$ terahertz photonic-crystal cavity in
a quantizing magnetic field, demonstrating a cooperativity of $\sim$360. The
splitting of cyclotron resonance (CR) into the lower and upper polariton
branches exhibited a $\sqrt{n_\mathrm{e}}$-dependence on the electron density
($n_\mathrm{e}$), a hallmark of collective vacuum Rabi splitting. Furthermore,
a small but definite blue shift was observed for the polariton frequencies due
to the normally negligible $A^2$ term in the light-matter interaction
Hamiltonian. Finally, the high-$Q$ cavity suppressed the superradiant decay of
coherent CR, which resulted in an unprecedentedly narrow intrinsic CR linewidth
of 5.6 GHz at 2 K. These results open up a variety of new possibilities to
combine the traditional disciplines of many-body condensed matter physics and
cavity-based quantum optics.


title:
Ground and bound state solutions for a Schr\"odinger system with linear
  and nonlinear couplings in $\mathbb{R}^N$

abstract:
  We study the existence of ground and bound state solutions for a system of
coupled Schr\"odinger equations with linear and nonlinear couplings in
$\mathbb{R}^N$. By studying the limit system and using concentration
compactness arguments, we prove the existence of ground and bound state
solutions under suitable assumptions. Our results are new even for the limit
system.


title: On the clique number of a strongly regular graph

abstract:
  We determine new upper bounds for the clique numbers of strongly regular
graphs in terms of their parameters. These bounds improve on the Delsarte bound
for infinitely many feasible parameter tuples for strongly regular graphs,
including infinitely many parameter tuples that correspond to Paley graphs.


title:
Factorization of Radiative Leptonic Decays of $B^-$ and $D^-$ Mesons
  Including the Soft Photon Region

abstract:
  In this work, we study the radiative leptonic decays of $B^-$ and $D^-$
mesons using factorization approach. Factorization is proved to be valid
explicitly at 1-loop level at any order of $O(\Lambda_{\rm
QCD}\left/m_Q\right.)$. We consider the contribution in the soft photon region
that $E_{\gamma} \sim \left. \Lambda^2_{\rm QCD} /\right. m_Q$. The numerical
results shows that, the soft photon region is very important for both the $B$
and $D$ mesons. The branching ratios of $B\to \gamma e\nu_e$ is $5.21\times
10^{-6}$, which is about $3$ times of the result obtained by only considering
the hard photon region $E_{\gamma}\sim m_Q$. And for the case of $D\to \gamma
e\nu_e$, the result of the branching ratio is $1.92\times 10^{-5}$.


title: The Galactic Center: A PeV Cosmic Ray Acceleration Factory

abstract:
  The multi-TeV $\gamma$-rays from the Galactic Center (GC) have a cutoff at
tens of TeV, whereas the diffuse emission has no such cutoff, which is regarded
as an indication of PeV proton acceleration by the HESS experiment. It is
important to understand the inconsistency and study the possibility that PeV
cosmic-ray acceleration could account for the apparently contradictory point
and diffuse $\gamma$-ray spectra. In this work, we propose that the cosmic rays
are accelerated up to $>$PeV in GC. The interaction between cosmic rays and
molecular clouds is responsible for the multi-TeV $\gamma$-ray emissions from
both the point source and diffuse sources today. Enhanced by the small volume
filling factor (VFF) of the clumpy structure, the absorption of the
$\gamma$-rays leads to a sharp cutoff spectrum at tens of TeV produced in the
GC. Away from galactic center, the VFF grows and the absorption enhancement
becomes negligible. As a result, the spectra of $\gamma$-ray emissions for both
point source and diffuse sources can be successfully reproduced under such
self-consistent picture. In addition, a "surviving-tail" at $\sim$100 TeV is
expected from the point source, which can be observed by future projects CTA
and LHAASO. Neutrinos are simultaneously produced during proton-proton (PP)
collision. With 5-10 years observations, the KM3Net experiment will be able to
detect the PeV source according to our calculation.


title: Superradiance from few emitters with non-radiative decay

abstract:
  Description of superradiance of few quantum emitters with non-radiative decay
in terms of quantum states is presented. Quantum efficiencies (QE) of SR of two
and three emitters are calculated and compared with the case of two and three
independent emitters. Maximum increase in QE is 8% for two emitters and 16% for
three emitters, it is reached at certain ratios between non-radiative and
radiative rates. Approach can be generalized with inclusion of the incoherent
pump, dephasing and delay in emitter-emitter interaction.


title: On Irreducible Polynomials of the Form $b(x^d)$

abstract:
  Let $p$ be a prime and $b(x)$ be an irreducible polynomial of degree $k$ over
$\mathbb{F}_p$. Let $d\geq 1$ be an integer. Consider the following question:
Is $b(x^d)$ irreducible? We derive necessary conditions for $b(x^d)$ to be
irreducible. Further, when the necessary conditions are satisfied, we obtain
the probability for $b(x^d)$ to be irreducible.


title: Stochastic $R$ matrix for $U_q(A^{(1)}_n)$

abstract:
  We show that the quantum $R$ matrix for symmetric tensor representations of
$U_q(A^{(1)}_n)$ satisfies the sum rule required for its stochastic
interpretation under a suitable gauge. Its matrix elements at a special point
of the spectral parameter are found to factorize into the form that naturally
extends Povolotsky's local transition rate in the $q$-Hahn process for $n=1$.
Based on these results we formulate new discrete and continuous time integrable
Markov processes on a one-dimensional chain in terms of $n$ species of
particles obeying asymmetric stochastic dynamics. Bethe ansatz eigenvalues of
the Markov matrices are also given.


title: Complex martingales and asymptotic enumeration

abstract:
  Many enumeration problems in combinatorics, including such fundamental
questions as the number of regular graphs, can be expressed as high-dimensional
complex integrals. Motivated by the need for a systematic study of the
asymptotic behaviour of such integrals, we establish explicit bounds on the
exponentials of complex martingales. Those bounds applied to the case of
truncated normal distributions are precise enough to include and extend many
enumerative results of Barvinok, Canfield, Gao, Greenhill, Hartigan, Isaev,
McKay, Wang, Wormald, and others. Our method applies to sums as well as
integrals.
  As a first illustration of the power of our theory, we considerably
strengthen existing results on the relationship between random graphs or
bipartite graphs with specified degrees and the so-called $\beta$-model of
random graphs with independent edges, which is equivalent to the Rasch model in
the bipartite case.


title: Far-infrared and sub-millimetre imaging of HD~76582's circumstellar disk

abstract:
  Debris disks, the tenuous rocky and icy remnants of planet formation, are
believed to be evidence for planetary systems around other stars. The
JCMT/SCUBA-2 debris disk legacy survey 'SCUBA-2 Observations of Nearby Stars'
(SONS) observed 100 nearby stars, amongst them HD~76582, for evidence of such
material. Here we present imaging observations by JCMT/SCUBA-2 and
\textit{Herschel}/PACS at sub-millimetre and far-infrared wavelengths,
respectively. We simultaneously model the ensemble of photometric and imaging
data, spanning optical to sub-millimetre wavelengths, in a self-consistent
manner. At far-infrared wavelengths, we find extended emission from the
circumstellar disk providing a strong constraint on the dust spatial location
in the outer system, although the angular resolution is too poor to constrain
the interior of the system. In the sub-millimetre, photometry at 450 and
850~$\mu$m reveal a steep fall-off that we interpret as a disk dominated by
moderately-sized dust grains ($a_{\rm min}~=~36~\mu$m), perhaps indicative of a
non-steady-state collisional cascade within the disk. A disk architecture of
three distinct annuli, comprising an unresolved component at $\sim$ 20 au and
outer components at 80 and 270 au, along with a very steep particle size
distribution ($\gamma~=~5$), is proposed to match the observations.


title:
Probing the origin of 750 GeV diphoton excess with the precision
  measurements at the ILC

abstract:
  The recently reported diphoton excess at the LHC may imply the existence of a
new resonance with a mass of about 750 GeV which couples to photons via loops
of new charged particles. In this letter, we study the possibility to test such
models at the ILC, paying attention to the new charged particles responsible
for the diphoton decay of the resonance. We show that they affect the
scattering processes $e^+e^- \to f\bar{f}$ (with $f$ denoting Standard Model
fermions) at the ILC, which makes it possible to indirectly probe the new
charged particles even if they are out of the kinematical reach. We also show
that the discriminations of the diphoton models may be possible based on a
study of the angular distributions of $f\bar{f}$.


title:
Gravitational bending angle of light for finite distance and the
  Gauss-Bonnet theorem

abstract:
  We discuss a possible extension of calculations of the bending angle of light
in a static, spherically symmetric and asymptotically flat spacetime to a
non-asymptotically flat case. We examine a relation between the bending angle
of light and the Gauss-Bonnet theorem by using the optical metric. A
correspondence between the deflection angle of light and the surface integral
of the Gaussian curvature may allow us to take account of the finite distance
from a lens object to a light source and a receiver. Using this relation, we
propose a method for calculating the bending angle of light for such cases.
Finally, this method is applied to two examples of the non-asymptotically flat
spacetimes to suggest finite-distance corrections: Kottler (Schwarzschild-de
Sitter) solution to the Einstein equation and an exact solution in Weyl
conformal gravity.


title: Effects of Mg/Si on Exoplanetary Refractory Oxygen Budget

abstract:
  Solar photospheric abundances of refractory elements mirror the Earth's to
within ~10 mol% when normalized to the dominant terrestrial planet-forming
elements Mg, Si and Fe. This allows for the adoption of Solar composition as an
order-of-magnitude proxy for Earth's. It is not known, however, the degree to
which this mirroring of stellar and terrestrial planet abundances holds true
for other star-planet systems without determination of the composition of
initial planetesimals via condensation sequence calculations and post
condensation processes. We present the open-source Arbitrary Composition
Condensation Sequence calculator (ArCCoS) to assess how the elemental
composition of a parent star affects that of the planet-building material,
including the extent of oxidation within the planetesimals. We demonstrate the
utility of ArCCoS by showing how variations in the abundance of the stellar
refractory elements Mg and Si affect the condensation of oxygen, a controlling
factor in the relative proportions of planetary core and silicate mantle
material. This, thereby, removes significant degeneracy in the interpretation
of the structures of exoplanets as well as providing observational tests for
the validity of this model.


title: Plasmonic Superradiance of Two Emitters Near Metal Nanorod

abstract:
  Quantum emitters, such as q-dots and dye molecules, in the immediate vicinity
of plasmonic nanostructures, resonantly excite surface plasmon-polaritons
(SPPs) under incoherent pump. The efficiency in the excitation of SPPs
increases as the number of the emitters, because the SPP field synchronizes
emission of the coupled emitters, in analogy with the superadiance (SR) of
coupled emitters in free space. Using fully quantum mechanical model for two
emitters coupled to a single gold nanorod, we predict up to 15% increase in the
emission yield of single emitter compared to only one emitter coupled to the
nanorod due to plasmonic SR. (XW: I use emission yield because the quantum
efficiency is one for emitters in free space and there is no room for
enhancement). Such emission enhancement is stationary and should be observable
even with strong dissipation and dephasing under incoherent pump. Solid-state
quantum emitters with blinking behaviors may be utilized to demonstrate such
plasmonic SR emission enhancement. Plasmonic SR may find implications in the
excitation of non-radiative modes in plasmonic waveguides; and lowing threshold
of plasmonic nanolasers.


title:
Reaction Mechanisms of Synthesis of 3,4-Epoxybutyric Acid from
  3-Hydroxy-{\gamma}-Butyrolactone by Density Functional Theory

abstract:
  In this paper, carried out were the investigations on the synthetic reaction
mechanisms of 3,4-epoxybutyric acid (EBA) from 3-hydroxy-{\gamma}-butyrolactone
(HBL) with two different activating agents, methanesulfonyl chloride (MC) or
acetic acid (AA), respectively, and on the convertion of EBA to L-carnitine by
density functional theory (DFT/B3LYP). The theoretical calculations showed that
the two reaction mechanisms of EBA synthesis with MC or AA as an activating
agent were nearly the same. If activated HBL is hydrolysed, not only ring
cleavage reaction, but also reverse reaction to HBL can take place. In the case
of AA as the activating agent, the activation energy ( energy barrier ) for EBA
synthesis is 1.8 times larger than that with MC. It means that the synthesis of
EBA with AA may make more by-products with less yield of EBA than that with MC,
that can be one reason why AA gave the less yield than MC in EBA synthesis, as
reported in the previous experimental study.


title:
Adaptive multiscale model reduction with Generalized Multiscale Finite
  Element Methods

abstract:
  In this paper, we discuss a general multiscale model reduction framework
based on multiscale finite element methods. We give a brief overview of related
multiscale methods. Due to page limitations, the overview focuses on a few
related methods and is not intended to be comprehensive. We present a general
adaptive multiscale model reduction framework, the Generalized Multiscale
Finite Element Method. Besides the method's basic outline, we discuss some
important ingredients needed for the method's success. We also discuss several
applications. The proposed method allows performing local model reduction in
the presence of high contrast and no scale separation.


title: Jet-dilepton conversion from an anisotropic quark-gluon plasma

abstract:
  We calculate the yield of lepton pair production from jet-plasma interaction
where the plasma is anisotropic in momentum space. We compare both the $M$ and
$p_T$ distributions from such process with the Drell-Yan contribution. It is
observed that the invariant mass distribution of lepton pair from such process
dominate over the Drell-Yan up to $3$ GeV at RHIC and up to $10$ GeV at LHC.
Moreover, it is found that the contribution from anistropic quark gluon plasma
(AQGP) increases marginally compared to the isotropic QGP. In case of
$p_T$-distribution we observe an increase by a factor of $3-4$ in the entire
$p_T$-range at RHIC for AQGP. However, at LHC the change in the
$p_T$-distribution is marginal as compared to the isotropic case.


title: A hybrid algorithm for coupling PDE and compartment-based dynamics

abstract:
  Stochastic simulation methods can be applied successfully to model exact
spatio-temporally resolved reaction-diffusion systems. However, in many cases,
these methods can quickly become extremely computationally intensive with
increasing particle numbers. An alternative description of many of these
systems can be derived in the diffusive limit as a deterministic, continuum
system of partial differential equations. Although the numerical solution of
such partial differential equations is, in general, much more efficient than
the full stochastic simulation, the deterministic continuum description is
generally not valid when copy numbers are low and stochastic effects dominate.
Therefore, to take advantage of the benefits of both of these types of models,
each of which may be appropriate in different parts of a spatial domain, we
have developed an algorithm that can be used to couple these two types of model
together. This hybrid coupling algorithm uses an overlap region between the two
modelling regimes. By coupling fluxes at one end of the interface and using a
concentration-matching condition at the other end, we ensure that mass is
appropriately transferred between PDE- and compartment-based regimes. Our
methodology gives notable reductions in simulation time in comparison with
using a fully stochastic model, whilst maintaining the important stochastic
features of the system and providing detail in appropriate areas of the domain.
We test our hybrid methodology robustly by applying it to several biologically
motivated problems including diffusion and morphogen gradient formation. Our
analysis shows that the resulting error is small, unbiased and does not grow
over time.


title: Index Modulation Techniques for 5G Wireless Networks

abstract:
  The increasing demand for higher data rates, better quality of service, fully
mobile and connected wireless networks lead the researchers to seek new
solutions beyond 4G wireless systems. It is anticipated that 5G wireless
networks, which are expected to be introduced around 2020, will achieve ten
times higher spectral and energy efficiency than current 4G wireless networks
and will support data rates up to 10 Gbps for low mobility users. The ambitious
goals set for 5G wireless networks require dramatic changes in the design of
different layers for next generation communications systems. Massive
multiple-input multiple-output (MIMO) systems, filter bank multi-carrier (FBMC)
modulation, relaying technologies, and millimeter-wave communications have been
considered as some of the strong candidates for the physical layer design of 5G
networks. In this article, we shed light on the potential and implementation of
index modulation (IM) techniques for MIMO and multi-carrier communications
systems which are expected to be two of the key technologies for 5G systems.
Specifically, we focus on two promising applications of IM: spatial modulation
(SM) and orthogonal frequency division multiplexing with IM (OFDM-IM), and we
discuss the recent advances and future research directions in IM technologies
towards spectral and energy-efficient 5G wireless networks.


title:
Information gain versus interference in Bohr's principle of
  complementarity

abstract:
  Based on modern quantum measurement theory, we use Zurek's "triple model" to
study, from the viewpoint of quantum information theory, the wave and particle
nature of a photon in a symmetric Mach-Zehnder interferometer. In the process
of quantum measurement, the state of both the system and the detector is not an
entangled state but a correlated state. We find that the information gain about
the photon is related to the correlations (including classical and quantum
correlations) between the photon and the detector. We also derive the
relationship between the information gain and the fringe visibility. We find
that the classical correlations remain consistent with the path
distinguishability and can be used to describe the particle-like property of
the photon. Quantum correlations are not exactly the same as fringe visibility,
but both can represent the quantum coherence of the photon. Finally, we provide
an analytical expression for quantum correlations of one type of two-qubit
separable states.


title: On the deformation of inversive distance circle packings

abstract:
  In this paper, we generalize Chow-Luo's combinatorial Ricci flow to inversive
distance circle packing setting. Although the solution to the generalized flow
may develop singularities in finite time, we can always extend the solution so
as it exists for all time and converges exponentially fast. Thus the
generalized flow can be used to deform any inversive distance circle packing to
a unique packing with prescribed cone angle. We also give partial results on
the range of all admissible cone angles, which generalize the classical
Andreev-Thurston's theorem.


title: On the deformation of discrete conformal factors on surfaces

abstract:
  In \cite{Luo0}, Feng Luo conjectured that the discrete Yamabe flow will
converge to the constant curvature PL-metric after finite number of surgeries
on the triangulation. In this paper, we prove that the flow can always be
extended (without surgeries) to a solution that converges exponentially fast to
the constant curvature PL-metric.


title: Capacity-Achieving Iterative LMMSE Detection for MIMO-NOMA Systems

abstract:
  This paper considers a Iterative Linear Minimum Mean Square Error (LMMSE)
detection for the uplink Multiuser Multiple-Input and Multiple-Output (MU-MIMO)
systems with Non-Orthogonal Multiple Access (NOMA), in which all the users
interfere with each other both in the time domain and frequency domain. It is
well known that the Iterative LMMSE detection greatly reduces the system
computational complexity by departing the overall processing into many
low-complexity distributed calculations that can be executed in parallel.
However, it is generally considered to be suboptimal and achieves relatively
poor performance due to its sub-optimal detector. In this paper, we firstly
present the matching conditions and area theorems for the iterative detection
of the MIMO-NOMA systems. Based on the matching conditions and area theorems,
the achievable rate region of the Iterative LMMSE detection is analysed.
Interestingly, we prove that by properly design the Iterative LMMSE detection,
it can achieve (i) the optimal capacity of symmetric MIMO-NOMA system, (ii) the
optimal sum capacity of asymmetric MIMO-NOMA system, (iii) all the maximal
extreme points in the capacity region of asymmetric MIMO-NOMA system, (iv) the
whole capacity region of two-user and three-user asymmetric MIMO-NOMA systems,
in a distributed manner for all cases. Finally, a practical Iterative LMMSE
detection design is also proposed for the general asymmetric MIMO-NOMA systems.


title:
Sequential Bayesian optimal experimental design via approximate dynamic
  programming

abstract:
  The design of multiple experiments is commonly undertaken via suboptimal
strategies, such as batch (open-loop) design that omits feedback or greedy
(myopic) design that does not account for future effects. This paper introduces
new strategies for the optimal design of sequential experiments. First, we
rigorously formulate the general sequential optimal experimental design (sOED)
problem as a dynamic program. Batch and greedy designs are shown to result from
special cases of this formulation. We then focus on sOED for parameter
inference, adopting a Bayesian formulation with an information theoretic design
objective. To make the problem tractable, we develop new numerical approaches
for nonlinear design with continuous parameter, design, and observation spaces.
We approximate the optimal policy by using backward induction with regression
to construct and refine value function approximations in the dynamic program.
The proposed algorithm iteratively generates trajectories via exploration and
exploitation to improve approximation accuracy in frequently visited regions of
the state space. Numerical results are verified against analytical solutions in
a linear-Gaussian setting. Advantages over batch and greedy design are then
demonstrated on a nonlinear source inversion problem where we seek an optimal
policy for sequential sensing.


title:
Optical study of the antiferromagnetic ordered state in
  electron-overdoped Ca0.77Nd0.23FeAs2

abstract:
  In Ca1-xRExFeAs2 (RE= rare earth), an antiferromagnetic (AFM) phase as well
as a structural transition has been reported, even in the electron-overdoped
regime. Here we investigated the temperature-dependent in-plane optical
spectroscopy of overdoped Ca0.77Nd0.23FeAs2. Upon entering the AFM state, we
found an abrupt reduction of low-frequency (500-2 000 cm-1) spectral weight in
the optical conductivity. In sharp contrast to the parent compounds of 122
system, where spin-density-wave gaps have been clearly observed in the AFM
state, a gap signature is absent in Ca0.77Nd0.23FeAs2. This may be a
consequence of the poor nesting condition between hole and electron pockets.
However, a spectral weight analysis shows that the reduced spectral weight at
low frequency is transferred to the high frequency range (> 4 000 cm-1),
pointing to a localization effect. These observations suggest that the AFM
order in Ca0.77Nd0.23FeAs2 is most likely to originate from a localized nature
rather than Fermi surface nesting.


title: Development of a wearable haptic game interface

abstract:
  This paper outlines the development and evaluation of a wearable haptic game
interface. The device differs from many traditional haptic feedback
implementation in that it combines vibrotactile feedback with gesture based
input, thus becoming a two way conduit between the user and the virtual
environment. The device is intended to challenge what is considered an
"interface" and sets out to purposefully blur the boundary between man and
machine. This allows for a more immersive experience, and a user evaluation
shows that the intuitive interface allows the user to become the aircraft that
is controlled by the movements of the user's hand.


title:
Dynamics near the ground state for the energy critical nonlinear heat
  equation in large dimensions

abstract:
  We consider the energy critical semilinear heat equation $$\partial_tu=\Delta
u+|u|^{\frac{4}{d-2}}u, \ \ x\in \mathbb R^d$$ and give a complete
classification of the flow near the ground state solitary wave
$$Q(x)=\frac{1}{\left( 1+\frac{|x|^2}{d(d-2)}\right)^{\frac{d-2}{2}}}$$ in
dimension $d\ge 7$, in the energy critical topology and without radial symmetry
assumption. Given an initial data $Q+\varepsilon_0$ with $\parallel \nabla
\varepsilon_0\parallel_{L^2}\ll 1$, the solution either blows up in the ODE
type I regime, or dissipates, and these two open sets are separated by a
codimension one set of solutions asymptotically attracted by the solitary wave.
In particular, non self similar type II blow up is ruled out in dimension $d\ge
7$ near the solitary wave even though it is known to occur in smaller
dimensions. Our proof is based on sole energy estimates deeply and draws a
route map for the classification of the flow near the solitary wave in the
energy critical setting. A by-product of our method is the classification of
minimal elements around $Q$ belonging to the unstable manifold.


title: Numerical Bifurcation for the Capillary Whitham Equation

abstract:
  The so-called Whitham equation arises in the modeling of free surface water
waves, and combines a generic nonlinear quadratic term with the exact linear
dispersion relation for gravity waves on the free surface of a fluid with
finite depth.
  In this work, the effect of incorporating capillarity into the Whitham
equation is in focus. The capillary Whitham equation is a nonlocal equation
similar to the usual Whitham equation, but containing an additional term with a
coefficient depending on the Bond number T which measures the relative strength
of capillary and gravity effects on the wave motion.
  A spectral collocation scheme for computing approximations to periodic
traveling waves for the capillary Whitham equation is put forward. Numerical
approximations of periodic traveling waves are computed using a bifurcation
approach, and a number of bifurcation curves are found. Our analysis uncovers a
rich structure of bifurcation patterns, including subharmonic bifurcations, as
well as connecting and crossing branches. Indeed, for some values of the Bond
number T, the bifurcation diagram features distinct branches of solutions which
intersect at a secondary bifurcation point. The same branches may also cross
without connecting, and some bifurcation curves feature self-crossings without
self-connections.


title:
Cohomology of $\mathfrak {aff}(1)$ and $\mathfrak {aff}(1|1)$ acting on
  the space of $n$-ary differential operators on the superspace
  $\mathbb{R}^{1|1}$

abstract:
  We consider the $\mu$-densities spaces $\mathcal{F}_\mu$ with
$\mu\in\mathbb{R}$, we compute the space
$\mathrm{H}^1_\mathrm{diff}(\mathfrak{aff}(1),\mathrm{D}_{\lambda,\mu})$ where
$\lambda=(\lambda_1,\dots,\lambda_n)\in\mathbb{R}^n$ and
$\mathrm{D}_{\lambda,\mu}$ is the space of $n$-ary differential operators from
$\mathcal{F}_{\lambda_1}\otimes\cdots\otimes\mathcal{F}_{\lambda_n}$ to
$\mathcal{F}_\mu$. We also compute the super analog space
$\mathrm{H}^1_\mathrm{diff}(\mathfrak{aff}(1|1),\mathfrak{D}_{\lambda,\mu})$.


title: Random walks with the minimum degree local rule have $O(n^2)$ cover time

abstract:
  For a simple (unbiased) random walk on a connected graph with $n$ vertices,
the cover time (the expected number of steps it takes to visit all vertices) is
at most $O(n^3)$. We consider locally biased random walks, in which the
probability of traversing an edge depends on the degrees of its endpoints. We
confirm a conjecture of Abdullah, Cooper and Draief [2015] that the min-degree
local bias rule ensures a cover time of $O(n^2)$. For this we formulate and
prove the following lemma about spanning trees.
  Let $R(e)$ denote for edge $e$ the minimum degree among its two endpoints. We
say that a weight function $W$ for the edges is feasible if it is nonnegative,
dominated by $R$ (for every edge $W(e) \le R(e)$) and the sum over all edges of
the ratios $W(e)/R(e)$ equals $n-1$. For example, in trees $W(e) = R(e)$, and
in regular graphs the sum of edge weights is $d(n-1)$.
  {\bf Lemma:} for every feasible $W$, the minimum weight spanning tree has
total weight $O(n)$.
  For regular graphs, a similar lemma was proved by Kahn, Linial, Nisan and
Saks [1989].


title: Functional flows in QED and the modified Ward-Takahashi identity

abstract:
  In the functional renormalisation group approach to gauge theory, the
Ward-Takahashi identity is modified due to the presence of an infrared cutoff
term. It take the most accessible form for the Wilsonian effective action.
  In the present work we solve these identities, partially, for the Wilson
effective action of QED. In particular, we compute the longitudinal part of the
photon two point vertex function as a momentum- dependent function in the
presence of the cutoff k. The resultant Wilsonian effective action carries form
factors that originate from the modified Ward-Takahashi identity. We show how
this result carries over to the one-particle-irreducible effective action.


title:
Masses of Third Family Vector-like Quarks and Leptons in Yukawa-Unified
  $E_6$

abstract:
  In supersymmetric $E_6$ the masses of the third family quarks and charged
lepton, $t-b-\tau$, as well as the masses of the vector-like quarks and
leptons, $D-\bar{D}$ and $ L-\bar{L}$, may arise from the coupling $27_3$ x
$27_3$ x $27_H$, where $27_3$ and $27_H$ denote the third family matter and
Higgs multiplets respectively. We assume that the SO(10) singlet component in
$27_H$ acquires a TeV scale VEV which spontaneously breaks U(1)$_\psi$ and
provides masses to the vector-like particles in $27_3$, while the MSSM doublets
in $27_H$ provide masses to $ t, b$ and $\tau$. Imposing Yukawa coupling
unification $h_t=h_b=h_{\tau}=h_D=h_L$ at $M_{GUT}$ and employing the ATLAS and
CMS constraints on the $Z'_\psi$ boson mass, we estimate the lower bounds on
the third family vector-like particles $D-\bar{D}$ and $L-\bar{L}$ masses to be
around 5.85 TeV and 2.9 TeV respectively. These bounds apply in the
supersymmetric limit.


title: Wavelength mismatch effect in electromagnetically induced absorption

abstract:
  We present a theoretical investigation of the phenomenon of
electromagnetically induced absorption (EIA) in a 4-level system consisting of
vee and ladder subsystems. The four levels are coupled using one weak probe
field, and two strong control fields. We consider an experimental realization
using energy levels of Rb. This necessitates dealing with different conditions
of wavelength mismatch---near-perfect match where all three wavelengths are
approximately equal; partial mismatch where the wavelength of one control field
is less than the other fields; and complete mismatch where all three
wavelengths are unequal. We present probe absorption profiles with Doppler
averaging at room temperature to account for experiments in a room temperature
Rb vapor cell. Our analysis shows that EIA resonances can be studied using
Rydberg states excited with diode lasers.


title:
Server Consolidation for Internet Applications in Virtualized Data
  Centers

abstract:
  Server consolidation based on virtualization technology simplifies system
administration and improves energy efficiency by improving resource
utilizations and reducing the physical machine (PM) number in contemporary
service-oriented data centers. The elasticity of Internet applications changes
the consolidation technologies from addressing virtual machines (VMs) to PMs
mapping schemes which must know the VMs statuses, i.e. the number of VMs and
the profiling data of each VM, into providing the application-to-VM-to-PM
mapping. In this paper, we study on the consolidation of multiple Internet
applications, minimizing the number of PMs with required performance. We first
model the consolidation providing the application-to-VM-to-PM mapping to
minimize the number of PMs as an integer linear programming problem, and then
present a heuristic algorithm to solve the problem in polynomial time.
Extensive experimental results show that our heuristic algorithm consumes less
than 4.3% more resources than the optimal amounts with few overheads. Existing
consolidation technologies using the input of the VM statuses output by our
heuristic algorithm consume 1.06% more PMs.


title:
On the limits of measuring the bulge and disk properties of local and
  high-redshift massive galaxies

abstract:
  A considerable fraction of the massive quiescent galaxies at \emph{z}
$\approx$ 2, which are known to be much more compact than galaxies of
comparable mass today, appear to have a disk. How well can we measure the bulge
and disk properties of these systems? We simulate two-component model galaxies
in order to systematically quantify the effects of non-homology in structures
and the methods employed. We employ empirical scaling relations to produce
realistic-looking local galaxies with a uniform and wide range of
bulge-to-total ratios ($B/T$), and then rescale them to mimic the
signal-to-noise ratios and sizes of observed galaxies at \emph{z} $\approx$ 2.
This provides the most complete set of simulations to date for which we can
examine the robustness of two-component decomposition of compact disk galaxies
at different $B/T$. We confirm that the size of these massive, compact galaxies
can be measured robustly using a single S\'{e}rsic fit. We can measure $B/T$
accurately without imposing any constraints on the light profile shape of the
bulge, but, due to the small angular sizes of bulges at high redshift, their
detailed properties can only be recovered for galaxies with $B/T$ \gax\ 0.2.
The disk component, by contrast, can be measured with little difficulty.


title:
Revisiting van der Waals like behavior of f(R) AdS black holes via the
  two point correlation function

abstract:
  Van der Waals like behavior of $f(R)$ AdS black holes is revisited via two
point correlation function, which is dual to the geodesic length in the bulk.
The equation of motion constrained by the boundary condition is solved
numerically and both the effect of boundary region size and $f(R)$ gravity are
probed. Moreover, an analogous specific heat related to $\delta L$ is
introduced. It is shown that the $T-\delta L$ graphs of $f(R)$ AdS black holes
exhibit reverse van der Waals like behavior just as the $T-S$ graphs do. Free
energy analysis is carried out to determine the first order phase transition
temperature $T_*$ and the unstable branch in $T-\delta L$ curve is removed by a
bar $T=T_*$. It is shown that the first order phase transition temperature is
the same at least to the order of $10^{-10}$ for different choices of the
parameter $b$ although the values of free energy vary with $b$. Our result
further supports the former finding that charged $f(R)$ AdS black holes behave
much like RN-AdS black holes. We also check the analogous equal area law
numerically and find that the relative errors for both the cases $\theta_0=0.1$
and $\theta_0=0.2$ are small enough. The fitting functions between $ \log\mid T
-T_c\mid$ and $\log\mid\delta L-\delta L_c\mid $ for both cases are also
obtained. It is shown that the slope is around 3, implying that the critical
exponent is about $2/3$. This result is in accordance with those in former
literatures of specific heat related to the thermal entropy or entanglement
entropy.


title:
Cancellation of Infrared Divergence in Inclusive Production of Lepton
  Pair Near the Threshold of Heavy Quarkonia

abstract:
  The detailed proof of cancellation of topologically unfactorized infrared
divergences in the inclusive production of lepton pair close to the threshold
of heavy quarkonia is presented. To make the effects of transition between
states containing heavy quark pairs, which is important in such cancellation,
the final detected states are constrained to be lepton pair near the threshold
of the heavy quarkonia instead of heavy quarkonia themselves. Such cancellation
is crucial for the NRQCD factorization of these processes.


title: The VORTEX coronagraphic test bench

abstract:
  In this paper, we present the infrared coronagraphic test bench of the
University of Li\`ege named VODCA (Vortex Optical Demonstrator for
Coronagraphic Applications). The goal of the bench is to assess the
performances of the Annular Groove Phase Masks (AGPMs) at near- to mid-infrared
wavelengths. The AGPM is a subwavelength grating vortex coronagraph of charge
two (SGVC2) made out of diamond. The bench is designed to be completely
achromatic and will be composed of a super continuum laser source emitting in
the near to mid-infrared, several parabolas, diaphragms and an infrared camera.
This way, we will be able to test the different AGPMs in the M, L, K and H
bands. Eventually, the bench will also allow the computation of the incident
wavefront aberrations on the coronagraph. A reflective Lyot stop will send most
of the stellar light to a second camera to perform low-order wavefront sensing.
This second system coupled with a deformable mirror will allow the correction
of the wavefront aberrations. We also aim to test other pre- and/or
post-coronagraphic concepts such as optimal apodization.


title: Managing Deadline-constrained Bag-of-Tasks Jobs on Hybrid Clouds

abstract:
  Outsourcing jobs to a public cloud is a cost-effective way to address the
problem of satisfying the peak resource demand when the local cloud has
insufficient resources. In this paper, we study on managing
deadline-constrained bag-of-tasks jobs on hybrid clouds. We present a binary
nonlinear programming (BNP) problem to model the hybrid cloud management where
the utilization of physical machines (PMs) in the local cloud/cluster is
maximized when the local resources are enough to satisfy the deadline
constraints of jobs, while when not, the rent cost from the public cloud is
minimized. To solve this BNP problem in polynomial time, we proposed a
heuristic algorithm. Its main idea is assigning the task closest to its
deadline to current core until the core cannot finish any task within its
deadline. When there is no available core, the algorithm adds an available PM
with most capacity or rents a new VM with highest cost-performance ratio.
Extensive experimental results show that our heuristic algorithm saves
16.2%-76% rent cost and improves 47.3%-182.8% resource utilizations satisfying
deadline constraints, compared with first fit decreasing algorithm.


title:
An Autonomous Reactive Architecture for Efficient AUV Mission Time
  Management in Realistic Severe Ocean Environment

abstract:
  Today AUVs operation still remains restricted to very particular tasks with
low real autonomy due to battery restrictions. Efficient motion planning and
mission scheduling are principle requirement toward advance autonomy and
facilitate the vehicle to handle long-range operations. A single vehicle cannot
carry out all tasks in a large scale terrain; hence, it needs a certain degree
of autonomy in performing robust decision making and awareness of the
mission/environment to trade-off between tasks to be completed, managing the
available time, and ensuring safe deployment at all stages of the mission. In
this respect, this research introduces a modular control architecture including
higher/lower level planners, in which the higher level module is responsible
for increasing mission productivity by assigning prioritized tasks while
guiding the vehicle toward its final destination in a terrain covered by
several waypoints; and the lower level is responsible for vehicle's safe
deployment in a smaller scale encountering time-varying ocean current and
different uncertain static/moving obstacles similar to actual ocean
environment. Synchronization between higher and lower level modules is
efficiently configured to manage the mission time and to guarantee on-time
termination of the mission. The performance and accuracy of two higher and
lower level modules are tested and validated using ant colony and firefly
optimization algorithm, respectively. After all, the overall performance of the
architecture is investigated in 10 different mission scenarios. The analyze of
the captured results from different simulated missions confirm the efficiency
and inherent robustness of the introduced architecture in efficient time
management, safe deployment, and providing beneficial operation by proper
prioritizing the tasks in accordance with mission time.


title: Decomposition of integer-valued polynomial algebras

abstract:
  Let $D$ be a commutative domain with field of fractions $K$, let $A$ be a
torsion-free $D$-algebra, and let $B$ be the extension of $A$ to a $K$-algebra.
The set of integer-valued polynomials on $A$ is ${\rm Int}(A) = \{f \in B[X]
\mid f(A) \subseteq A\}$, and the intersection of ${\rm Int}(A)$ with $K[X]$ is
${\rm Int}_K(A)$, which is a commutative subring of $K[X]$. The set ${\rm
Int}(A)$ may or may not be a ring, but it always has the structure of a left
${\rm Int}_K(A)$-module.
  A $D$-algebra $A$ which is free as a $D$-module and of finite rank is called
${\rm Int}_K$-decomposable if a $D$-module basis for $A$ is also an ${\rm
Int}_K(A)$-module basis for ${\rm Int}(A)$; in other words, if ${\rm Int}(A)$
can be generated by ${\rm Int}_K(A)$ and $A$. A classification of such algebras
has been given when $D$ is a Dedekind domain with finite residue rings. In the
present article, we modify the definition of ${\rm Int}_K$-decomposable so that
it can be applied to $D$-algebras that are not necessarily free by defining $A$
to be ${\rm Int}_K$-decomposable when ${\rm Int}(A) \cong {\rm Int}_K(A)
\otimes_D A$. We then provide multiple characterizations of such algebras in
the case where $D$ is a discrete valuation ring or a Dedekind domain with
finite residue rings. In particular, if $D$ is the ring of integers of a number
field $K$, we show that ${\rm Int}_K$-decomposable algebras $A$ correspond to
maximal $D$-orders in a separable $K$-algebra $B$, whose simple components have
as center the same finite unramified Galois extension $F$ of $K$ and are
unramified at each finite place of $F$. Finally, when both $D$ and $A$ are
rings of integers in number fields, we show that ${\rm Int}_K$-decomposable
algebras correspond to unramified Galois extensions of $K$.


title: Quasistatic crack growth in 2d-linearized elasticity

abstract:
  In this paper we prove a two-dimensional existence result for a variational
model of crack growth for brittle materials in the realm of linearized
elasticity. Starting with a time-discretized version of the evolution driven by
a prescribed boundary load, we derive a time-continuous quasistatic crack
growth in the framework of generalized special functions of bounded deformation
(GSBD). As the time-discretization step tends to $0$, the major difficulty lies
in showing the stability of the static equilibrium condition, which is achieved
by means of a Jump Transfer Lemma generalizing the result of Francfort and
Larsen [Comm. Pure Appl. Math., 56 (2003), 1465--1500] to the GSBD setting.
Moreover, we present a general compactness theorem for this framework and prove
existence of the evolution without the necessity of a-priori bounds on the
displacements or applied body forces.


title:
Magnification relations of quad lenses and applications on Einstein
  crosses

abstract:
  In this work, we mainly study the magnification relations of quad lens models
for cusp, fold and cross configurations. By dividing and ray-tracing in
different image regions, we numerically derive the positions and magnifications
of the four images for a point source lying inside of the astroid caustic.
Then, based on the magnifications, we calculate the signed cusp and fold
relations for the singular isothermal elliptical lenses. The signed fold
relation map has positive and negative regions, and the positive region is
usually larger than the negative region as has been confirmed before. It can
also explain that for many observed fold image pairs, the fluxes of the Fermat
minimum images are apt to be larger than those of the saddle images. We define
a new quantity cross relation which describes the magnification discrepancy
between two minimum images and two saddle images. Distance ratio is also
defined as the ratio of the distance of two saddle images to that of two
minimum images. We calculate the cross relations and distance ratios for nine
observed Einstein crosses. In theory, for most of the quad lens models, the
cross relations decrease as the distance ratios increase. In observation, the
cross relations of the nine samples do not agree with the quad lens models very
well, nevertheless, the cross relations of the nine samples do not give obvious
evidence for anomalous flux ratio as the cusp and fold types do. Then, we
discuss several reasons for the disagreement, and expect good consistencies for
more precise observations and better lens models in the future.


title: Semantic Reasoning for Context-aware Internet of Things Applications

abstract:
  Advances in ICT are bringing into reality the vision of a large number of
uniquely identifiable, interconnected objects and things that gather
information from diverse physical environments and deliver the information to a
variety of innovative applications and services. These sensing objects and
things form the Internet of Things (IoT) that can improve energy and cost
efficiency and automation in many different industry fields such as
transportation and logistics, health care and manufacturing, and facilitate our
everyday lives as well. IoT applications rely on real-time context data and
allow sending information for driving the behaviors of users in intelligent
environments.


title: Effects of the noise level on stochastic fractional heat equations

abstract:
  We consider the stochastic fractional heat equation
$\partial_{t}u=\triangle^{\alpha/2}u+\lambda\sigma(u)\dot{w}$ on $[0,L]$ with
Dirichlet boundary conditions, where $\dot{w}$ denotes the space-time white
noise. For any $\lambda>0$, we prove that the $p$th moment of $\sup_{x\in
[0,L]}|u(t,x)|$ grows at most exponentially. Moreover, we prove that the $p$th
moment of $\sup_{x\in [0,L]}|u(t,x)|$ is exponentially stable if $\lambda$ is
small. At last, We obtain the noise excitation index of $p$th energy of
$u(t,x)$ as $\lambda\rightarrow \infty$.


title:
Graph Minors for Preserving Terminal Distances Approximately - Lower and
  Upper Bounds

abstract:
  Given a graph where vertices are partitioned into $k$ terminals and
non-terminals, the goal is to compress the graph (i.e., reduce the number of
non-terminals) using minor operations while preserving terminal distances
approximately.The distortion of a compressed graph is the maximum
multiplicative blow-up of distances between all pairs of terminals. We study
the trade-off between the number of non-terminals and the distortion. This
problem generalizes the Steiner Point Removal (SPR) problem, in which all
non-terminals must be removed.
  We introduce a novel black-box reduction to convert any lower bound on
distortion for the SPR problem into a super-linear lower bound on the number of
non-terminals, with the same distortion, for our problem. This allows us to
show that there exist graphs such that every minor with distortion less than
$2~/~2.5~/~3$ must have $\Omega(k^2)~/~\Omega(k^{5/4})~/~\Omega(k^{6/5})$
non-terminals, plus more trade-offs in between. The black-box reduction has an
interesting consequence: if the tight lower bound on distortion for the SPR
problem is super-constant, then allowing any $O(k)$ non-terminals will not help
improving the lower bound to a constant.
  We also build on the existing results on spanners, distance oracles and
connected 0-extensions to show a number of upper bounds for general graphs,
planar graphs, graphs that exclude a fixed minor and bounded treewidth graphs.
Among others, we show that any graph admits a minor with $O(\log k)$ distortion
and $O(k^{2})$ non-terminals, and any planar graph admits a minor with
$1+\varepsilon$ distortion and $\widetilde{O}((k/\varepsilon)^{2})$
non-terminals.


title:
Universality of pseudogap and emergent order in lightly doped Mott
  insulators

abstract:
  It is widely believed that high-temperature superconductivity in the cuprates
emerges from doped Mott insulators. The physics of the parent state seems
deceivingly simple: The hopping of the electrons from site to site is
prohibited because their on-site Coulomb repulsion U is larger than the kinetic
energy gain t. When doping these materials by inserting a small percentage of
extra carriers, the electrons become mobile but the strong correlations from
the Mott state are thought to survive; inhomogeneous electronic order, a
mysterious pseudogap and, eventually, superconductivity appear. How the
insertion of dopant atoms drives this evolution is not known, nor whether these
phenomena are mere distractions specific to hole-doped cuprates or represent
the genuine physics of doped Mott insulators. Here, we visualize the evolution
of the electronic states of (Sr1-xLax)2IrO4, which is an effective spin-1/2
Mott insulator like the cuprates, but is chemically radically different. Using
spectroscopic-imaging STM, we find that for doping concentration of x=5%, an
inhomogeneous, phase separated state emerges, with the nucleation of pseudogap
puddles around clusters of dopant atoms. Within these puddles, we observe the
same glassy electronic order that is so iconic for the underdoped cuprates.
Further, we illuminate the genesis of this state using the unique possibility
to localize dopant atoms on topographs in these samples. At low doping, we find
evidence for much deeper trapping of carriers compared to the cuprates. This
leads to fully gapped spectra with the chemical potential at mid-gap, which
abruptly collapse at a threshold of around 4%. Our results clarify the melting
of the Mott state, and establish phase separation and electronic order as
generic features of doped Mott insulators.


title:
Group velocity locked vector dissipative solitons in a high repetition
  rate fiber laser

abstract:
  Vectorial nature of dissipative solitons (DSs) with high repetition rates is
studied for the first time in a normal-dispersion fiber laser. Despite the fact
that the formed DSs are strongly chirped and the repetition rate is greater
than 100 MHz, polarization locked and polarization rotating group velocity
locked vector DSs can be formed under 129.3 MHz fundamental mode-locking and
258.6 MHz harmonic mode-locking of the fiber laser, respectively. The two
orthogonally polarized components of these vector DSs possess distinctly
different central wavelengths and travel together at the same group velocity in
the laser cavity, resulting in a gradual spectral edge and small steps on the
optical spectra, which can be considered as an auxiliary indicator of the group
velocity locked vector DSs.


title: Advances in Property-Based Testing for $\alpha$Prolog

abstract:
  $\alpha$Check is a light-weight property-based testing tool built on top of
$\alpha$Prolog, a logic programming language based on nominal logic.
$\alpha$Prolog is particularly suited to the validation of the meta-theory of
formal systems, for example correctness of compiler translations involving
name-binding, alpha-equivalence and capture-avoiding substitution. In this
paper we describe an alternative to the negation elimination algorithm
underlying $\alpha$Check that substantially improves its effectiveness. To
substantiate this claim we compare the checker performances w.r.t. two of its
main competitors in the logical framework niche, namely the QuickCheck/Nitpick
combination offered by Isabelle/HOL and the random testing facility in
PLT-Redex.


title: A Fast Algorithm for Lattice Hyperonic Potentials

abstract:
  We describe an efficient algorithm to compute a large number of baryon-baryon
interactions from $NN$ to $\Xi\Xi$ by means of HAL QCD method, which lays the
groundwork for the nearly physical point lattice QCD calculation with volume
$(96a)^4\approx$($8.2$fm)$^4$. Preliminary results of $\Lambda N$ potential
calculated with quark masses corresponding to
($m_{\pi}$,$m_{K}$)$\approx$(146,525)MeV are presented.


title: Dynamics of skyrmionic states in confined helimagnetic nanostructures

abstract:
  In confined helimagnetic nanostructures, skyrmionic states in the form of
incomplete and isolated skyrmion states can emerge as the ground state in
absence of both external magnetic field and magnetocrystalline anisotropy. In
this work, we study the dynamic properties (resonance frequencies and
corresponding eigenmodes) of skyrmionic states in thin film FeGe disk samples.
We employ two different methods in finite-element based micromagnetic
simulation: eigenvalue and ringdown method. The eigenvalue method allows us to
identify all resonance frequencies and corresponding eigenmodes that can exist
in the simulated system. However, using a particular experimentally feasible
excitation can excite only a limited set of eigenmodes. Because of that, we
perform ringdown simulations that resemble the experimental setup using both
in-plane and out-of-plane excitations. In addition, we report the nonlinear
dependence of resonance frequencies on the external magnetic bias field and
disk sample diameter and discuss the possible reversal mode of skyrmionic
states. We compare the power spectral densities of incomplete skyrmion and
isolated skyrmion states and observe several key differences that can
contribute to the experimental identification of the state present in the
sample. We measure the FeGe Gilbert damping, and using its value we determine
what eigenmodes can be expected to be observed in experiments. Finally, we show
that neglecting the demagnetisation energy contribution or ignoring the
magnetisation variation in the out-of-film direction - although not changing
the eigenmode's magnetisation dynamics significantly - changes their resonance
frequencies substantially. Apart from contributing to the understanding of
skyrmionic states physics, this systematic work can be used as a guide for the
experimental identification of skyrmionic states in confined helimagnetic
nanostructures.


title: On the algebraic structure of Weihrauch degrees

abstract:
  We introduce two new operations (compositional products and implication) on
Weihrauch degrees, and investigate the overall algebraic structure. The
validity of the various distributivity laws is studied and forms the basis for
a comparison with similar structures such as residuated lattices and concurrent
Kleene algebras. Introducing the notion of an ideal with respect to the
compositional product, we can consider suitable quotients of the Weihrauch
degrees. We also prove some specific characterizations using the implication.
In order to introduce and study compositional products and implications, we
introduce and study a function space of multi-valued continuous functions. This
space turns out to be particularly well-behaved for effectively traceable
spaces that are closely related to admissibly represented spaces.


title:
Temperature evolution of magnetic structure of HoFeO$_3$ by single
  crystal neutron diffraction

abstract:
  We have investigated the temperature evolution of the magnetic structures of
HoFeO$_3$ by single crystal neutron diffraction. The three different magnetic
structures found as a function of temperature for \hfo\ are described by the
magnetic groups Pb$'$n$'2_1$, Pbn$2_1$ and Pbn$'2_1'$ and are stable in the
temperature ranges $\approx$ 600-55~K, 55-37~K and 35$>T>2$~K respectively. In
all three the fundamental coupling between the Fe sub-lattices remains the same
and only their orientation and the degree of canting away from the ideal axial
direction varies. The magnetic polarisation of the Ho sub-lattices in these two
higher temperature regions, in which the major components of the Fe moment lie
along $x$ and $y$, is very small. The canting of the moments from the axial
directions is attributed to the antisymmetric interactions allowed by the
crystal symmetry. They include contributions from single ion anisotropy as well
as the Dzyaloshinski antisymmetric exchange. In the low temperature phase two
further structural transitions are apparent in which the spontaneous
magnetisation changes sign with respect to the underlying antiferromagnetic
configuration. In this temperature range the antisymmetric exchange energy
varies rapidly as the the Ho sub-lattices begin to order. So long as the
ordered Ho moments are small the antisymmetric exchange is due only to Fe-Fe
interactions, but as the degree of Ho order increases the Fe-Ho interactions
take over whilst at the lowest temperatures, when the Ho moments approach
saturation the Ho-Ho interactions dominate. The reversals of the spontaneous
magnetisation found in this study suggest that in \hfo\ the sums of the Fe-Fe
and Ho-Ho antisymmetric interactions have the same sign as one another, but
that of the Ho-Fe terms is opposite.


title: Cut-and-paste restoration of entanglement transmission

abstract:
  The distribution of entangled quantum systems among two or more nodes of a
network is a key task at the basis of quantum communication, quantum
computation and quantum cryptography. Unfortunately the transmission lines used
in this procedure can introduce so much perturbations and noise in the
transmitted signal that prevent the possibility of restoring quantum
correlations in the received messages either by means of encoding optimization
or by exploiting local operations and classical communication. In this work we
present a procedure which allows one to improve the performance of some of
these channels. The mechanism underpinning this result is a protocol which we
dub cut-and-paste, as it consists in extracting and reshuffling the
sub-components of these communication lines, which finally succeed in
"correcting each other". The proof of this counterin- tuitive phenomenon, while
improving our theoretical understanding of quantum entanglement, has also a
direct application in the realization of quantum information networks based on
imperfect and highly noisy communication lines. A quantum optics experiment,
based on the transmission of single-photon polarization states, is also
presented which provides a proof-of-principle test of the proposed protocol.


title: On the semimartingale property of Brownian bridges on complete manifolds

abstract:
  I prove that every adapted Brownian bridge on a geodesically complete
connected Riemannian manifold is a semimartingale including its terminal time,
without any further assumptions on the geometry. In particular, it follows that
every such process can be horizontally lifted to a smooth principal fiber
bundle with connection, including its terminal time. The proof is based on a
localized Hamilton-type gradient estimate by Arnaudon/Thalmaier.


title:
Joint Line Segmentation and Transcription for End-to-End Handwritten
  Paragraph Recognition

abstract:
  Offline handwriting recognition systems require cropped text line images for
both training and recognition. On the one hand, the annotation of position and
transcript at line level is costly to obtain. On the other hand, automatic line
segmentation algorithms are prone to errors, compromising the subsequent
recognition. In this paper, we propose a modification of the popular and
efficient multi-dimensional long short-term memory recurrent neural networks
(MDLSTM-RNNs) to enable end-to-end processing of handwritten paragraphs. More
particularly, we replace the collapse layer transforming the two-dimensional
representation into a sequence of predictions by a recurrent version which can
recognize one line at a time. In the proposed model, a neural network performs
a kind of implicit line segmentation by computing attention weights on the
image representation. The experiments on paragraphs of Rimes and IAM database
yield results that are competitive with those of networks trained at line
level, and constitute a significant step towards end-to-end transcription of
full documents.


title:
Formation of high-order acoustic Bessel beams by spiral diffraction
  gratings

abstract:
  The formation of high-order Bessel beams by a passive acoustic device
consisting of an Archimedes' spiral diffraction grating is theoretically,
numerically and experimentally reported in this work. These beams are
propagation-invariant solutions of the Helmholtz equation and are characterized
by an azimuthal variation of the phase along its annular spectrum producing an
acoustic vortex in the near field. In our system, the scattering of plane
acoustic waves by the spiral grating leads to the formation of the acoustic
vortex with zero pressure on-axis and the angular phase dislocations
characterized by the spiral geometry. The order of the generated Bessel beam
and, as a consequence, the size of the generated vortex can be fixed by the
number of arms in the spiral diffraction grating. The obtained results allow to
obtain Bessel beams with controllable vorticity by a passive device, which has
potential applications in low-cost acoustic tweezers and acoustic radiation
force devices.


title: Inferring interaction partners from protein sequences

abstract:
  Specific protein-protein interactions are crucial in the cell, both to ensure
the formation and stability of multi-protein complexes, and to enable signal
transduction in various pathways. Functional interactions between proteins
result in coevolution between the interaction partners, causing their sequences
to be correlated. Here we exploit these correlations to accurately identify
which proteins are specific interaction partners from sequence data alone. Our
general approach, which employs a pairwise maximum entropy model to infer
couplings between residues, has been successfully used to predict the
three-dimensional structures of proteins from sequences. Thus inspired, we
introduce an iterative algorithm to predict specific interaction partners from
two protein families whose members are known to interact. We first assess the
algorithm's performance on histidine kinases and response regulators from
bacterial two-component signaling systems. We obtain a striking 0.93 true
positive fraction on our complete dataset without any a priori knowledge of
interaction partners, and we uncover the origin of this success. We then apply
the algorithm to proteins from ATP-binding cassette (ABC) transporter
complexes, and obtain accurate predictions in these systems as well. Finally,
we present two metrics that accurately distinguish interacting protein families
from non-interacting ones, using only sequence data.


title: Mid-IR AGPMs for ELT applications

abstract:
  The mid-infrared region is well suited for exoplanet detection thanks to the
reduced contrast between the planet and its host star with respect to the
visible and near-infrared wavelength regimes. This contrast may be further
improved with Vector Vortex Coronagraphs (VVCs), which allow us to cancel the
starlight. One flavour of the VVC is the AGPM (Annular Groove Phase Mask),
which adds the interesting properties of subwavelength gratings (achromaticity,
robustness) to the already known properties of the VVC. In this paper, we
present the optimized designs, as well as the expected performances of mid-IR
AGPMs etched onto synthetic diamond substrates, which are considered for the
E-ELT/METIS instrument.


title:
Characterization of specific nuclear reaction channels by deconvolution
  in the energy space of the total nuclear cross-section of protons -
  applications to proton therapy and technical problems (transmutations)

abstract:
  The total nuclear cross-section Qtot(E) resulting from the interaction of
protons with nuclei is decomposed in 3 different contributions: 1. elastic
scatter at the complete nucleus, which adopts a part of the proton kinetic
energy; 2. inelastic scatter at a nucleus, which changes its quantum numbers by
vibrations, rotations, transition to highly excited states; 3. proper nuclear
reactions with change of the mass and/or charge number. Then different
particles leave the hit nucleus (neutrons, protons, etc.), which is now
referred to as 'heavy recoil' nucleus. The scatter parts of Qtot(E) according
to points 1 and 2 can be removed by a deconvolution acting at Qtot(E) in the
energy space. The typical nuclear reaction channels are mainly characterized by
resonances of a reduced cross-section function Qred(E). The procedure is
applied to cross-sections of therapeutic protons and also to Cs55137 as an
example with technical relevance (transmutations with the goal to drastically
reduce its half-time).


title: A signaling protocol for service function localization

abstract:
  Current proposals for combining service functions (SFs) do not address some
critical management issues, such as the discovery of SF instances close to IP
data paths. This information is crucial for deploying complex services both in
large cloud networks, where SFs may be moved or replicated, and in the emerging
fog/mobile edge computing systems. For this purpose, in this letter we propose
the distributed off-path signaling protocol (OSP). We show the protocol
functions and demonstrate its scalability and effectiveness by experimental
results.


title:
Angular momentum and topological dependence of Kepler's Third Law in the
  Broucke-Hadjidemetriou-H\'enon family of periodic three-body orbits

abstract:
  We use 57 recently found topological satellites of
Broucke-Hadjidemetriou-Henon's periodic orbits with values of the topological
exponent $k$ ranging from $k$ = 3 to $k$ = 58 to plot the angular momentum $L$
as a function of the period $T$, with both $L$ and $T$ rescaled to energy
$E=-\frac12$. Upon plotting $L(T/k)$ we find that all our solutions fall on a
curve that is virtually indiscernible by naked eye from the $L(T)$ curve for
non-satellite solutions. The standard deviation of the satellite data from the
sixth-order polynomial fit to the progenitor data is $\sigma = 0.13$. This
regularity supports Henon's 1976 conjecture that the linearly stable
Broucke-Hadjidemetriou-Henon orbits are also perpetually, or
Kolmogorov-Arnold-Moser stable.


title:
Ideal convergent subsequences and rearrangements for divergent sequences
  of functions

abstract:
  Let $\I$ be an ideal on $\N$ which is either analytic or coanalytic. Assume
that $(f_n)$ is a sequence of functions with the Baire property from a Polish
space $X$ into a complete metric space $Z$, which is divergent on a comeager
set. We investigate the Baire category of $\I$-convergent subsequences and
rearrangements of $(f_n)$. Our result generalizes a theorem of Kallman. A
similar theorem for subsequences is obtained if $(X,\mu)$ is a $\sigma$-finite
complete measure space and a sequence $(f_n)$ of measurable functions from $X$
to $Z$ is $\I$-divergent $\mu$-almost everywhere. Then the set of subsequences
of $(f_n)$, $\I$-divergent $\mu$-almost everywhere, is of full product measure
on $\{ 0,1\}^\N$. Here we assume additionally that $\mathcal I$ has property
(G).


title:
Constraints on LISA Pathfinder's self-gravity: design requirements,
  estimates and testing procedures

abstract:
  LISA Pathfinder satellite has been launched on 3th December 2015 toward the
Sun-Earth first Lagrangian point (L1) where the LISA Technology Package (LTP),
which is the main science payload, will be tested. With its cutting-edge
technology, the LTP will provide the ability to achieve unprecedented geodesic
motion residual acceleration measurements down to the order of $3 \times
10^{-14}\,\mathrm{m/s^2/{Hz^{1/2}}}$ within the $1-30\,\mathrm{mHz}$ frequency
band. The presence of the spacecraft itself is responsible of the local
gravitational field which will interact with the two proof test-masses.
Potentially, such a force interaction might prevent to achieve the targeted
free-fall level originating a significant source of noise. We balanced this
gravitational force with sub $\mathrm{nm/s^2}$ accuracy, guided by a protocol
based on measurements of the position and the mass of all parts that constitute
the satellite, via finite element calculation tool estimates. In the following,
we will introduce requirements, design and foreseen on-orbit testing
procedures.


title:
Completely exceptional $2^\textrm{nd}$ order PDEs via conformal geometry
  and BGG resolution

abstract:
  By studying the development of shock waves out of discontinuity waves, in
1954 P. Lax discovered a class of PDEs, which he called 'completely
exceptional', where such a transition does not occur after a finite time. A
straightforward integration of the completely exceptionality conditions allowed
Boillat to show that such PDEs are actually of Monge-Ampere type. In this
paper, we first recast these conditions in terms of characteristics, and then
we show that the completely exceptional PDEs, with 2 or 3 independent
variables, can be described in terms of the conformal geometry of the
Lagrangian Grassmannian, where they are naturally embedded. Moreover, for an
arbitrary number of independent variables, we show that the space of r-th
degree sections of the Lagrangian Grassmannian can be resolved via a BGG
operator. In the particular case of 1st degree sections, i.e., hyperplane
sections or, equivalently, Monge-Ampere equations, such operator is a close
analog of the trace-free second fundamental form.