title: The evolution of the Milky Way: New insights from open clusters

abstract:
  We have collected high-dispersion echelle spectra of red giant members in the
twelve open clusters (OCs) and derived stellar parameters and chemical
abundances for 26 species by either line equivalent widths or synthetic
spectrum analyses. We confirm the lack of an age-metallicity relation for OCs
but argue that such a lack of trend for OCs arise from the limited coverage in
metallicity compared to that of field stars which span a wide range in
metallicity and age. We confirm that the radial metallicity gradient of OCs is
steeper (flatter) for Rgc < 12 kpc (> 12 kpc). We demonstrate that the sample
of clusters constituting a steep radial metallicity gradient of slope
$-$0.052$\pm$0.011 dex kpc$^{-1}$ at Rgc < 12 kpc are younger than 1.5 Gyr and
located close to the Galactic midplane (|z| < 0.5 kpc) with kinematics typical
of the thin disc. Whereas the clusters describing a shallow slope of
$-$0.015$\pm$0.007 dex kpc$^{-1}$ at Rgc > 12 kpc are relatively old, thick
disc members with a striking spread in age and height above the midplane (0.5 <
|z| < 2.5 kpc). Our investigation reveals that the OCs and field stars yield
consistent radial metallicity gradients if the comparison is limited to samples
drawn from the similar vertical heights. We argue via the computation of
Galactic orbits that all the outer disc clusters were actually born inward of
12 kpc but the orbital eccentricity has taken them to present locations very
far from their birthplaces.


title: Soap-bubble Optimization of Gaits

abstract:
  In this paper, we present a geometric variational algorithm for optimizing
the gaits of kinematic locomoting systems. The dynamics of this algorithm are
analogous to the physics of a soap bubble, with the system's Lie bracket
supplying an "inflation pressure" that is balanced by a "surface tension" term
derived from a Riemannian metric on the system's shape space. We demonstrate
this optimizer on a variety of system geometries (including Purcell's swimmer)
and for optimization criteria that include maximizing displacement and
efficiency of motion for both translation and turning motions.


title: Memory Remains: Understanding Collective Memory in the Digital Age

abstract:
  Recently developed information communication technologies, particularly the
Internet, have affected how we, both as individuals and as a society, create,
store, and recall information. Internet also provides us with a great
opportunity to study memory using transactional large scale data, in a
quantitative framework similar to the practice in statistical physics. In this
project, we make use of online data by analysing viewership statistics of
Wikipedia articles on aircraft crashes. We study the relation between recent
events and past events and particularly focus on understanding memory
triggering patterns. We devise a quantitative model that explains the flow of
viewership from a current event to past events based on similarity in time,
geography, topic, and the hyperlink structure of Wikipedia articles. We show
that on average the secondary flow of attention to past events generated by
such remembering processes is larger than the primary attention flow to the
current event. We are the first to report these cascading effects.

categories: physics.soc-ph cs.CY cs.SI physics.data-an


title: Identifying Community Structures in Dynamic Networks

abstract:
  Most real-world social networks are inherently dynamic, composed of
communities that are constantly changing in membership. To track these evolving
communities, we need dynamic community detection techniques. This article
evaluates the performance of a set of game theoretic approaches for identifying
communities in dynamic networks. Our method, D-GT (Dynamic Game Theoretic
community detection), models each network node as a rational agent who
periodically plays a community membership game with its neighbors. During game
play, nodes seek to maximize their local utility by joining or leaving the
communities of network neighbors. The community structure emerges after the
game reaches a Nash equilibrium. Compared to the benchmark community detection
methods, D-GT more accurately predicts the number of communities and finds
community assignments with a higher normalized mutual information, while
retaining a good modularity.


title:
The weak coupling limit for the random Schr\"odinger equation: The
  average wave function

abstract:
  We consider the Schr\"odinger equation with a time-independent weakly random
potential of a strength $\epsilon\ll 1$, with Gaussian statistics. We prove
that when the initial condition varies on a scale much larger than the
correlation length of the potential, the compensated wave function converges to
a deterministic limit on the time scale $t\sim\epsilon^{-2}$. This is shown
under the sharp assumption that the correlation function $R(x)$ of the random
potential decays slower than $1/|x|^2$, which ensures that the effective
potential is finite. When $R(x)$ decays slower than $1/|x|^2$ we establish an
anomalous diffusive behavior for the averaged wave function on a time scale
shorter than $\epsilon^{-2}$, as long as the initial condition is "sufficiently
macroscopic". We also consider the kinetic regime when the initial condition
varies on the same scale as the random potential and obtain the limit of the
averaged wave function for potentials with the correlation functions decaying
faster than $1/|x|^2$. We use random potentials of the Schonberg class which
allows us to bypass the oscillatory phase estimates.


title: Regularity for Shape Optimizers: The Nondegenerate Case

abstract:
  We consider minimizers of
  \[
  F(\lambda_1(\Omega),\ldots,\lambda_N(\Omega)) + |\Omega|,
  \] where $F$ is a function strictly increasing in each parameter, and
$\lambda_k(\Omega)$ is the $k$-th Dirichlet eigenvalue of $\Omega$. Our main
result is that the reduced boundary of the minimizer is composed of
$C^{1,\alpha}$ graphs, and exhausts the topological boundary except for a set
of Hausdorff dimension at most $n-3$. We also obtain a new regularity result
for vector-valued Bernoulli type free boundary problems.


title:
Multifractal Solar EUV Intensity Fluctuations and their Implications for
  Coronal Heating Models

abstract:
  We investigate the scaling properties of the long-range temporal evolution
and intermittency of SDO/AIA intensity observations in four solar environments:
an active region core, a weak emission region, and two core loops. We use two
approaches: the probability distribution function (PDF) of time series
increments, and multifractal detrended fluctuation analysis (MF-DFA). Noise
taints the results, so we focus on the 171 Angstrom waveband , which has the
highest signal-to-noise ratio. The lags between pairs of wavebands distinguish
between coronal versus transition region (TR) emission. In all physical regions
studied, scaling in the range 15-45 min is multifractal, and the time series
are anti-persistent on the average. The degree of anti-correlation in the TR
time series is greater than for coronal emission. The multifractality stems
from long term correlations in the data rather than the wide distribution of
intensities. Observations in the 335 Angstrom waveband can be described in
terms of a multifractal with added noise. The multiscaling of the EUV data
agrees qualitatively with the radiance from a phenomenological model of
impulsive bursts plus noise, and also from ohmic dissipation in a reduced
magnetohydrodynamics (RMHD) model for coronal loop heating. The parameter space
must be further explored to seek quantitative agreement. Thus, the
observational signatures obtained by the combined tests of the PDF of
increments and the MF-DFA offer strong constraints which can systematically
discriminate among models for coronal heating.


title:
Extremely large magnetoresistance in a topological semimetal candidate
  pyrite PtBi2

abstract:
  While pyrite-type PtBi2 with face-centered cubic structure has been predicted
to be a three-dimensional (3D) Dirac semimetal, experimental study on its
physical properties remains absent. Here we report the angular-dependent
magnetoresistance (MR) measurements of PtBi2 single-crystal under high magnetic
fields. We observed extreme large unsaturated magnetoresistance (XMR) up to
11.2 million percent at T = 1.8 K in a magnetic field of 33 T, which surpasses
the previously reported Dirac materials, such as WTe2, LaSb and NbP. The
crystals exhibit an ultrahigh mobility and significant Shubnikov-de Hass (SdH)
quantum oscillations with nontrivial Berry's phase. Analysis of Hall
resistivity indicates that the XMR can be ascribed to the nearly compensated
electron and hole. Our experimental results associated with the ab initio
calculations suggest that pyrite PtBi2 is a topological semimetal candidate
which might provide a platform for exploring topological materials with XMR in
noble metal alloys.


title: Coloring trees in reverse mathematics

abstract:
  The tree theorem for pairs ($\mathsf{TT}^2_2$), first introduced by Chubb,
Hirst, and McNicholl, asserts that given a finite coloring of pairs of
comparable nodes in the full binary tree $2^{<\omega}$, there is a set of nodes
isomorphic to $2^{<\omega}$ which is homogeneous for the coloring. This is a
generalization of the more familiar Ramsey's theorem for pairs
($\mathsf{RT}^2_2$), which has been studied extensively in computability theory
and reverse mathematics. We answer a longstanding open question about the
strength of $\mathsf{TT}^2_2$, by showing that this principle does not imply
the arithmetic comprehension axiom ($\mathsf{ACA}_0$) over the base system,
recursive comprehension axiom ($\mathsf{RCA}_0$), of second-order arithmetic.
In addition, we give a new and self-contained proof of a recent result of Patey
that $\mathsf{TT}^2_2$ is strictly stronger than $\mathsf{RT}^2_2$. Combined,
these results establish $\mathsf{TT}^2_2$ as the first known example of a
natural combinatorial principle to occupy the interval strictly between
$\mathsf{ACA}_0$ and $\mathsf{RT}^2_2$. The proof of this fact uses an
extension of the bushy tree forcing method, and develops new techniques for
dealing with combinatorial statements formulated on trees, rather than on
$\omega$.


title:
Investigating the correlations of flow harmonics in 2.76A TeV Pb--Pb
  collisions

abstract:
  This proceeding briefly summarizes our recent investigations on the
correlations of flow harmonics in 2.76A TeV Pb--Pb collisions with viscous
hydrodynamics {\tt VISH2+1}. We calculated both the symmetric cumulants
$SC^{v}(m, n)$ and the normalized symmetric cumulants $NSC^{v}(m, n)$, and
found $v_{2}$ and $v_{4}$, $v_{2}$ and $v_{5}$, $v_{3}$ and $v_{5}$ are
correlated, $v_{2}$ and $v_{3}$, $v_{3}$ and $v_{4}$ are anti-correlated. We
also found $NSC^{v}(3, 2)$ are insensitive to the QGP viscosity, which are
mainly determined by the initial conditions.


title: Inferring social structure from continuous-time interaction data

abstract:
  Relational event data, which consist of events involving pairs of actors over
time, are now commonly available at the finest of temporal resolutions.
Existing continuous-time methods for modeling such data are based on point
processes and directly model interaction "contagion," whereby one interaction
increases the propensity of future interactions among actors, often as dictated
by some latent variable structure. In this article, we present an alternative
approach to using temporal-relational point process models for continuous-time
event data. We characterize interactions between a pair of actors as either
spurious or that resulting from an underlying, persistent connection in a
latent social network. We argue that consistent deviations from expected
behavior, rather than solely high frequency counts, are crucial for identifying
well-established underlying social relationships. This study aims to explore
these latent network structures in two contexts: one comprising of college
students and another involving barn swallows.


title:
A Characterization of the Boolean Prime Ideal Theorem in Terms of
  Forcing Notions

abstract:
  For certain weak versions of the Axiom of Choice (most notably, the Boolean
Prime Ideal theorem), we obtain equivalent formulations in terms of partial
orders, and filter-like objects within them intersecting certain dense sets or
antichains. This allows us to prove some consequences of the Boolean Prime
Ideal theorem using arguments in the style of those that use Zorn's Lemma, or
Martin's Axiom.


title:
Distributed Processing of Biosignal-Database for Emotion Recognition
  with Mahout

abstract:
  This paper investigates the use of distributed processing on the problem of
emotion recognition from physiological sensors using a popular machine learning
library on distributed mode. Specifically, we run a random forests classifier
on the biosignal-data, which have been pre-processed to form exclusive groups
in an unsupervised fashion, on a Cloudera cluster using Mahout. The use of
distributed processing significantly reduces the time required for the offline
training of the classifier, enabling processing of large physiological datasets
through many iterations.


title: Orbital classification in an N-body bar

abstract:
  The dynamics and evolution of any galactic structure are strongly influenced
by the properties of the orbits that constitute it. In this paper, we compare
two orbit classification schemes, one by Laskar (NAFF) , and the other by
Carpintero and Aguilar (CA), by applying both of them to orbits obtained by
following individual particles in a numerical simulation of a barred galaxy. We
find that, at least for our case and some provisos, the main frequencies
calculated by the two methods are in good agreement: for $80\%$ of the orbits
the difference between the results of the two methods is less than $5\%$ for
all three main frequencies. However, it is difficult to evaluate the amount of
regular or chaotic bar orbits in a given system. The fraction of regular orbits
obtained by the NAFF method strongly depends on the critical frequency drift
parameter, while in the CA method the number of fundamental frequencies
strongly depends on the frequency difference parameter $L_{\rm r}$ and the
maximum integer used for searching the linear independence of the fundamental
frequencies. We also find that, for a given particle, in general the projection
of its motion along the bar minor axis is more regular than the other two
projections, while the projection along the intermediate axis is the least
regular.


title:
On a Question of Hamkins and L\"owe on the modal logic of collapse
  forcing

abstract:
  Hamkins and L\"{o}we asked whether there can be a model $N$ of set theory
with the property that $N\equiv N[g]$ whenever $g$ is a generic collapse of a
cardinal of $N$ onto $\omega$. We give equiconsistency results for two weaker
versions of this property. We also include a proof of Woodin's result that the
consistency of the full Hamkins-L\"{o}we property follows from that of a Woodin
cardinal with an inaccessible above.


title: The efficient computation of Fourier transforms on semisimple algebras

abstract:
  We present a general diagrammatic approach to the construction of efficient
algorithms for computing a Fourier transform on a semisimple algebra. This
extends previous work wherein we derive best estimates for the computation of a
Fourier transform for a large class of finite groups. We continue to find
efficiencies by exploiting a connection between Bratteli diagrams and the
derived path algebra and construction of Gel'fand-Tsetlin bases. Particular
results include highly efficient algorithms for the Brauer, Temperley-Lieb
algebras, and Birman-Murakami-Wenzl algebras.


title:
The SAMI Galaxy Survey: Spatially resolving the environmental quenching
  of star formation in GAMA galaxies

abstract:
  We use data from the Sydney-AAO Multi-Object Integral Field Spectrograph
(SAMI) Galaxy Survey and the Galaxy And Mass Assembly (GAMA) survey to
investigate the spatially-resolved signatures of the environmental quenching of
star formation in galaxies. Using dust-corrected measurements of the
distribution of H$\alpha$ emission we measure the radial profiles of star
formation in a sample of 201 star-forming galaxies covering three orders of
magnitude in stellar mass (M$_{*}$; $10^{8.1}$-$10^{10.95}\, $M$_{\odot}$) and
in $5^{th}$ nearest neighbour local environment density ($\Sigma_{5}$;
$10^{-1.3}$-$10^{2.1}\,$Mpc$^{-2}$). We show that star formation rate gradients
in galaxies are steeper in dense ($\log_{10}(\Sigma_{5}/$Mpc$^{2})>0.5$)
environments by $0.58\pm 0.29\, dex\, $r$_{e}^{-1}$ in galaxies with stellar
masses in the range $10^{10}<$M$_{*}/$M$_{\odot}<10^{11}$ and that this
steepening is accompanied by a reduction in the integrated star formation rate.
However, for any given stellar mass or environment density the star-formation
morphology of galaxies shows large scatter. We also measure the degree to which
the star formation is centrally concentrated using the unitless scale-radius
ratio ($r_{50,H\alpha}/r_{50,cont}$), which compares the extent of ongoing star
formation to previous star formation. With this metric we find that the
fraction of galaxies with centrally concentrated star formation increases with
environment density, from $\sim 5\pm 4\%$ in low-density environments
($\log_{10}(\Sigma_{5}/$Mpc$^{2})<0.0$) to $30\pm 15\%$ in the highest density
environments ($\log_{10}(\Sigma_{5}/$Mpc$^{2})>1.0$). These lines of evidence
strongly suggest that with increasing local environment density the star
formation in galaxies is suppressed, and that this starts in their outskirts
such that quenching occurs in an outside-in fashion in dense environments and
is not instantaneous.


title: Picture groups of finite type and cohomology in type $A_n$

abstract:
  For every quiver (valued) of finite representation type we define a finitely
presented group called a picture group. This group is very closely related to
the cluster theory of the quiver. For example, positive expressions for the
Coxeter element in the group are in bijection with maximal green sequences
[IT17]. The picture group is derived from the semi-invariant picture for the
quiver. We use this picture to construct a finite CW complex which (by [IT16])
is a $K(\pi,1)$ for this group. The cells are in bijection with cluster tilting
objects. For example, in type $A_n$ there are a Catalan number of cells.
  The main result of this paper is the computation of the cohomology ring of
all picture groups of type $A_n$ with any orientation and any coefficient ring.


title:
Robustness of indispensable nodes in controlling protein-protein
  interaction network

abstract:
  Recently, the structural controllability theory has been introduced to
analyze the Protein-Protein Interaction (PPI) network. The indispensable nodes,
which their removal increase the number of driver nodes to control the network,
are found essential in PPI network. However, the PPI network is far from
complete and there may exist many false-positive or false-negative
interactions, which promotes us to question: are these indispensable nodes
robust to structural change? Here we systematically investigate the robustness
of indispensable nodes of PPI network by removing and adding possible
interactions. We found that the indispensable nodes are sensitive to the
structural change and very few edges can change the type of many indispensable
nodes. The finding may promote our understanding to the control principle of
PPI network.


title:
Robust Structure from Motion in the Presence of Outliers and Missing
  Data

abstract:
  Structure from motion is an import theme in computer vision. Although great
progress has been made both in theory and applications, most of the algorithms
only work for static scenes and rigid objects. In recent years, structure and
motion recovery of non-rigid objects and dynamic scenes have received a lot of
attention. In this paper, the state-of-the-art techniques for structure and
motion factorization of non-rigid objects are reviewed and discussed. First, an
introduction of the structure from motion problem is presented, followed by a
general formulation of non-rigid structure from motion. Second, an augmented
affined factorization framework, by using homogeneous representation, is
presented to solve the registration issue in the presence of outlying and
missing data. Third, based on the observation that the reprojection residuals
of outliers are significantly larger than those of inliers, a robust
factorization strategy with outlier rejection is proposed by means of the
reprojection residuals, followed by some comparative experimental evaluations.
Finally, some future research topics in non-rigid structure from motion are
discussed.


title:
Absolute Determination of Optical Constants by a Direct Physical
  Modeling of Reflection Electron Energy Loss Spectra

abstract:
  We present an absolute extraction method of optical constants of metal from
the measured reflection electron energy loss (REELS) spectra by using the
recently developed reverse Monte Carlo (RMC) technique. The method is based on
a direct physical modeling of electron elastic and electron inelastic
scattering near the surface region where the surface excitation becomes
important to fully describe the spectrum loss feature intensity in relative to
the elastic peak intensity. An optimization procedure of oscillator parameters
appeared in the energy loss function (ELF) for describing electron inelastic
scattering due to the bulk- and surface-excitations was performed with the
simulated annealing method by a successive comparison between the measured and
Monte Carlo simulated REELS spectra. The ELF and corresponding optical
constants of Fe were obtained from the REELS spectra measured at incident
energies of 1000, 2000 and 3000 eV. The validity of the present optical data
has been verified with the f- and ps-sum rules showing the accuracy and
applicability of the present approach. Our data are also compared with previous
optical data from other sources.


title: O(f) Bi-Approximation for Capacitated Covering with Hard Capacities

abstract:
  We consider capacitated vertex cover with hard capacity constraints (VC-HC)
on hypergraphs. In this problem we are given a hypergraph $G=(V,E)$ with a
maximum edge size $f$. Each edge is associated with a demand and each vertex is
associated with a weight (cost), a capacity, and an available multiplicity. The
objective is to find a minimum-weight vertex multiset such that the demands of
the edges can be covered by the capacities of the vertices and the multiplicity
of each vertex does not exceed its available multiplicity.
  In this paper we present an $O(f)$ bi-approximation for VC-HC that gives a
trade-off on the number of augmented multiplicity and the cost of the resulting
cover. In particular, we show that, by augmenting the available multiplicity by
a factor of $k \ge 2$, a~cover with a cost ratio of
$\Big(1+\frac{1}{k-1}\Big)(f-1)$ to the optimal cover for the original instance
can be obtained. This improves over a previous result, which has a cost ratio
of $f^2$ via augmenting the available multiplicity by a factor of $f$.


title:
Optical Signatures of Quantum Emitters in Suspended Hexagonal Boron
  Nitride

abstract:
  Hexagonal boron nitride (h-BN) is a tantalizing material for solid-state
quantum engineering. Analogously to three-dimensional wide-bandgap
semiconductors like diamond, h-BN hosts isolated defects exhibiting visible
fluorescence, and the ability to position such quantum emitters within a
two-dimensional material promises breakthrough advances in quantum sensing,
photonics, and other quantum technologies. Critical to such applications,
however, is an understanding of the physics underlying h-BN's quantum emission.
We report the creation and characterization of visible single-photon sources in
suspended, single-crystal, h-BN films. The emitters are bright and stable over
timescales of several months in ambient conditions. With substrate interactions
eliminated, we study the spectral, temporal, and spatial characteristics of the
defects' optical emission, which offer several clues about their electronic and
chemical structure. Analysis of the defects' spectra reveals similarities in
vibronic coupling despite widely-varying fluorescence wavelengths, and a
statistical analysis of their polarized emission patterns indicates a
correlation between the optical dipole orientations of some defects and the
primitive crystallographic axes of the single-crystal h-BN film. These
measurements constrain possible defect models, and, moreover, suggest that
several classes of emitters can exist simultaneously in free-standing h-BN,
whether they be different defects, different charge states of the same defect,
or the result of strong local perturbations.


title:
X-ray microtomographic visualization of Escherichia coli by
  metalloprotein overexpression

abstract:
  This paper reports X-ray microtomographic visualization of the microorganism
Escherichia coli overexpressing a metalloprotein ferritin. The
three-dimensional distribution of linear absorption coefficients determined
using a synchrotron radiation microtomograph with a simple projection geometry
revealed that the X-ray absorption was homogeneously distributed, suggesting
that every E. coli cell was labeled with the ferritin. The ferritin-expressing
E. coli exhibited linear absorption coefficients comparable to those of
phosphotungstic-acid stained cells. The submicrometer structure of the
ferritin-expressing E. coli cells was visualized by Zernike phase contrast
using an imaging microtomograph equipped with a Fresnel zone plate. The
obtained images revealed curved columnar or bunching oval structures
corresponding to the E. coli cells. These results indicate that the
metalloprotein overexpression facilitates X-ray visualization of
three-dimensional cellular structures of biological objects.


title: Chaos induced by sliding phenomena in Filippov systems

abstract:
  In this paper we provide a full topological and ergodic description of the
dynamics of Filippov systems nearby a sliding Shilnikov orbit. More
specifically we prove that the first return map, defined nearby this orbit, is
topologically conjugate to a Bernoulli shift with infinite topological entropy.
In particular, we see that for each natural number m it has infinitely many
periodic points with period m.


title:
Deformations of fundamental group representations and earthquakes on
  $SO(n,1)$ surface groups

abstract:
  In this article we construct a type of deformations of representations
$\pi_1(M)\rightarrow G$ where $G$ is an arbitrary lie group and $M$ is a large
class of manifolds including CAT(0) manifolds. The deformations are defined
based on codimension 1 hypersurfaces with certain conditions, and also on
disjoint union of such hypersurfaces, i.e. multi-hypersurfaces. We show
commutativity of deforming along disjoint hypersurfaces. As application, we
consider Anosov surface groups in $SO(n,1)$ and show that the construction can
be extended continuously to measured laminations, thus obtaining earthquake
deformations on these surface groups.


title:
Boosting the charged Higgs search prospects using jet substructure at
  the LHC

abstract:
  Charged Higgs bosons are predicted in variety of theoretically well-motivated
new physics models with extended Higgs sectors. In this study, we focus on a
type-II two Higgs doublet model (2HDM-II) and consider a heavy charged Higgs
with its mass ranging from 500 GeV to 1 TeV as dictated by the $b\to s\gamma$
constraints which render $M_{H^\pm}>480$ GeV. We study the dominant production
mode $H^\pm t$ associated production with $H^\pm \to W^\pm A$ being the
dominant decay channel when the pseudoscalar $A$ is considerably lighter. For
such a heavy charged Higgs, both the decay products $W^\pm$ and $A$ are
relatively boosted. In such a scenario, we apply the jet substructure analysis
of tagging the fat pseudoscalar and $W$ jets in order to eliminate the standard
model background efficiently. We perform a detailed detector simulation for the
signal and background processes at the 14 TeV LHC. We introduce various
kinematical cuts to determine the signal significance for a number of benchmark
points with charged Higgs boson mass from 500 GeV to 1 TeV in the $W^\pm A$
decay channel. Finally we perform a multivariate analysis utilizing a boosted
decision tree algorithm to optimize these significances.


title: Some Advances in Role Discovery in Graphs

abstract:
  Role discovery in graphs is an emerging area that allows analysis of complex
graphs in an intuitive way. In contrast to other graph prob- lems such as
community discovery, which finds groups of highly connected nodes, the role
discovery problem finds groups of nodes that share similar graph topological
structure. However, existing work so far has two severe limitations that
prevent its use in some domains. Firstly, it is completely unsupervised which
is undesirable for a number of reasons. Secondly, most work is limited to a
single relational graph. We address both these lim- itations in an intuitive
and easy to implement alternating least squares framework. Our framework allows
convex constraints to be placed on the role discovery problem which can provide
useful supervision. In par- ticular we explore supervision to enforce i)
sparsity, ii) diversity and iii) alternativeness. We then show how to lift this
work for multi-relational graphs. A natural representation of a
multi-relational graph is an order 3 tensor (rather than a matrix) and that a
Tucker decomposition allows us to find complex interactions between collections
of entities (E-groups) and the roles they play for a combination of relations
(R-groups). Existing Tucker decomposition methods in tensor toolboxes are not
suited for our purpose, so we create our own algorithm that we demonstrate is
pragmatically useful.


title:
Metalorganic chemical vapor deposition of hexagonal boron nitride on
  (001) sapphire substrates for thermal neutron detector applications

abstract:
  This paper reports on the growth and characterization of hexagonal boron
nitride (hBN) and its use for solid-state thermal neutron detection. The hBN
epilayers were grown by metalorganic chemical vapor deposition on sapphire
substrates at a temperature of 1350 C. X-ray diffraction peak from the (002)
hBN plane at a 2theta angle of 26.7 deg exhibited the c-lattice constant of
6.66 {\AA} for these films. A strong peak corresponding to the high frequency
Raman active mode of hBN was found for the films at 1370.5/cm. hBN-based
solid-state neutron detectors were fabricated and tested with a
metal-semiconductor-metal configuration with an electrode spacing of 1 mm and
hBN thickness of 2.5 micron. Fabricated detectors showed strong response to
deep UV light as well. An intrinsic thermal neutron detection efficiency of
0.86% was measured, which is close to the theoretically expected efficiency of
0.87%. These results demonstrate that epitaxial hBN films are promising for
thermal neutron detection applications.


title:
Experimental asymmetric Plug-and-Play Measurement-device-independent
  quantum key distribution

abstract:
  Measurement-device-independent quantum key distribution (MDI-QKD) is immune
to all security loopholes on detection. Previous experiments on MDI-QKD
required spatially separated signal lasers and complicated stabilization
systems. In this paper, we perform a proof-of-principle experimental
demonstration of plug-and-play MDI-QKD over an asymmetric channel setting with
a single signal laser, in which the whole system is automatically stabilized in
spectrum, polarization, arrival time and phase reference. Both the signal laser
and the single-photon detectors are in the possession of a common server. A
passive timing calibration technique is applied to ensure the precise and
stable overlap of signal pulses. The results pave the way for the realization
of a quantum network, in which the users only need the encoding devices.


title:
Molecular motions in glass and supercooled states of clotrimazole
  studied by broadband dielectric spectroscopy

abstract:
  The molecular mobility of glassy and supercooled liquid states of
clotrimazole is studied using broadband dielectric spectroscopy for a wide
range of temperatures and frequency. The dielectric loss data of clotrimazole
below T$_{g}$, do not show well resolved relaxation. Above T$_{g}$, dielectric
loss show the structural $\alpha$-relaxation which is reformed to shoulder like
shape at high frequencies due to the secondary relaxation. The relaxation time
of $\alpha$-process, $\tau_{\alpha}$ follows Vogel-Fulcher-Tammann equation.
The glass transition temperature, $T_{g}$=296K and fragility index, m=50 are
obtained from the thermal behaviour of the $\alpha$-process. At temperature
near T$_{g}$ the dielectric loss has Kohlrausch-Williams-Watts stretch
exponential parameter $\beta_{KWW}$=0.56. The primitive relaxation time
obtained from the coupling model coincides with the experimentally observed
secondary relaxation of clotrimazole. Hence the secondary relaxation is
considered to be the Johari-Goldstein (JG) process which may be the precursor
$\alpha$-process. The value of exponent $\beta_{KWW}$ increases with increase
of temperature and scaled dielectric loss do not form as single master curve.
The structural relaxation $\alpha$-relaxation and JG $\beta$-relaxation process
and its effects in clorimazole is discussed.


title: On sectoriality of degenerate elliptic operators

abstract:
  Let $c_{kl} \in W^{1,\infty}(\Omega, \mathbb{C})$ for all $k,l \in \{1,
\ldots, d\}$ and $\Omega \subset \mathbb{R}^d$ be open with Lipschitz boundary.
We consider the divergence form operator $ A_p = - \sum_{k,l=1}^d \partial_l
(c_{kl} \, \partial_k) $ in $L_p(\Omega)$ when the coefficient matrix satisfies
$(C(x) \, \xi, \xi) \in \Sigma_\theta$ for all $x \in \Omega$ and $\xi \in
\mathbb{C}^d$, where $\Sigma_\theta$ be the sector with vertex 0 and semi-angle
$\theta$ in the complex plane. We show that a sectorial estimate hold for $A_p$
for all $p$ in a suitable range. We then apply these estimates to prove that
the closure of $-A_p$ generates a holomorphic semigroup under further
assumptions on the coefficients. The contractivity and consistency properties
of these holomorphic semigroups are also considered.


title: Decentralized Observability with Limited Communication between Sensors

abstract:
  In this paper, we study the problem of jointly retrieving the state of a
dynamical system, as well as the state of the sensors deployed to estimate it.
We assume that the sensors possess a simple computational unit that is capable
of performing simple operations, such as retaining the current state and model
of the system in its memory.
  We assume the system to be observable (given all the measurements of the
sensors), and we ask whether each sub-collection of sensors can retrieve the
state of the underlying physical system, as well as the state of the remaining
sensors. To this end, we consider communication between neighboring sensors,
whose adjacency is captured by a communication graph. We then propose a linear
update strategy that encodes the sensor measurements as states in an augmented
state space, with which we provide the solution to the problem of retrieving
the system and sensor states.
  The present paper contains three main contributions. First, we provide
necessary and sufficient conditions to ensure observability of the system and
sensor states from any sensor. Second, we address the problem of adding
communication between sensors when the necessary and sufficient conditions are
not satisfied, and devise a strategy to this end. Third, we extend the former
case to include different costs of communication between sensors. Finally, the
concepts defined and the method proposed are used to assess the state of an
example of approximate structural brain dynamics through linearized
measurements.


title: Applying polynomial filtering to mass preconditioned Hybrid Monte Carlo

abstract:
  The use of mass preconditioning or Hasenbusch filtering in modern Hybrid
Monte Carlo simulations is common. At light quark masses, multiple filters
(three or more) are typically used to reduce the cost of generating dynamical
gauge fields; however, the task of tuning a large number of Hasenbusch mass
terms is non-trivial. The use of short polynomial approximations to the inverse
has been shown to provide an effective UV filter for HMC simulations. In this
work we investigate the application of polynomial filtering to the mass
preconditioned Hybrid Monte Carlo algorithm as a means of introducing many time
scales into the molecular dynamics integration with a simplified parameter
tuning process. A generalized multi-scale integration scheme that permits
arbitrary step- sizes and can be applied to Omelyan-style integrators is also
introduced. We find that polynomial-filtered mass-preconditioning (PF-MP)
performs as well as or better than standard mass preconditioning, with
significantly less fine tuning required.


title:
Experimental Demonstration of Passive-Decoy-State
  Quantum-Key-Distribution with Two Independent Lasers

abstract:
  Decoy state method could effectively enhance the performance of quantum key
distribution (QKD) with practical phase randomized weak coherent source.
Although active modulation of the source intensity is effective and has been
implemented in many experiments, passive preparation of decoy states is also an
important addition to the family of decoy state QKD protocols. In this paper,
following the theory of Curty \emph{et al.} [PRA, 81, 022310 (2010)], we
experimentally demonstrate the phase-encoding passive-decoy-state QKD with only
linear optical setups and threshold single photon detectors. In our experiment,
two homemade independent pulsed lasers, with visibility of Hong-Ou-Mandel
interference $0.53(\pm 0.003)$, have been implemented and used to passively
generate the different decoy states. Finally, secret key rate $1.5\times
10^{-5}$/pulse is obtained with 10km commercial fiber between Alice and Bob.


title:
Optimal Disease Outbreak Detection in a Community Using Network
  Observability

abstract:
  Given a network, we would like to determine which subset of nodes should be
measured by limited sensing facilities to maximize information about the entire
network. The optimal choice corresponds to the configuration that returns the
highest value of a measure of observability of the system. Here, the
determinant of the inverse of the observability Gramian is used to evaluate the
degree of observability. Additionally, the effects of changes in the topology
of the corresponding graph of a network on the observability of the network are
investigated. The theory is illustrated on the problem of detection of an
epidemic disease in a community. The purpose here is to find the smallest
number of people who must be examined to predict the number of infected people
in an arbitrary community. Results are demonstrated in simulation.


title:
Singularity structures and impacts on parameter estimation in finite
  mixtures of distributions

abstract:
  Singularities of a statistical model are the elements of the model's
parameter space which make the corresponding Fisher information matrix
degenerate. These are the points for which estimation techniques such as the
maximum likelihood estimator and standard Bayesian procedures do not admit the
root-$n$ parametric rate of convergence. We propose a general framework for the
identification of singularity structures of the parameter space of finite
mixtures, and study the impacts of the singularity structures on minimax lower
bounds and rates of convergence for the maximum likelihood estimator over a
compact parameter space. Our study makes explicit the deep links between model
singularities, parameter estimation convergence rates and minimax lower bounds,
and the algebraic geometry of the parameter space for mixtures of continuous
distributions. The theory is applied to establish concrete convergence rates of
parameter estimation for finite mixture of skew-normal distributions. This rich
and increasingly popular mixture model is shown to exhibit a remarkably complex
range of asymptotic behaviors which have not been hitherto reported in the
literature.


title: Effect of Nanodiamond surfaces on Drug Delivery Systems

abstract:
  The prospect of RNA nanotechnology is increasing because of its numerous
potential applications especially in medical science. The spherical
Nanodiamonds (NDs) are becoming popular because of their lesser toxicity,
desirable mechanical, optical properties, functionality and available surface
areas. On other hand RNAs are stable, flexible and easy to bind to the NDs. In
this work, we have studied the tRNA dynamics on ND surface by high-resolution
quasi-elastic neutron scattering spectroscopy and all atom molecular dynamics
simulation technique to understand how the tRNA motion is affected by the
presence of ND. The flexibly of the tRNA is analyzed by the Mean square
displacement analysis that shows tRNA have a sharp increase around 230K in its
hydrated form. The intermediate scattering function (ISF) representing the tRNA
dynamics follows the logarithmic decay as proposed by the Mode Coupling theory
(MCT). But most importantly the tRNA dynamics is found to be faster in presence
of ND within 220K to 310K compared to the freestanding ones. This is as we have
shown, is because of the swollen RNA molecule due the introduction of
hydrophilic ND surface.


title: Convex Independence in Permutation Graphs

abstract:
  A set C of vertices of a graph is P_3-convex if every vertex outside C has at
most one neighbor in C. The convex hull \sigma(A) of a set A is the smallest
P_3-convex set that contains A. A set M is convexly independent if for every
vertex x \in M, x \notin \sigma(M-x). We show that the maximal number of
vertices that a convexly independent set in a permutation graph can have, can
be computed in polynomial time.


title:
The extended Bloch Representation of Entanglement and Measurement in
  Quantum Mechanics

abstract:
  The quantum formalism can be completed by assuming that a density operator
can also represent a pure state. An 'extended Bloch representation' (EBR) then
results, in which not only states, but also the measurement-interactions can be
represented. The Born rule is obtained as an expression of the subjective lack
of knowledge about the measurement-interaction that is each time actualized.
Entanglement can also be consistently described in the EBR, as it remains
compatible with the principle according to which a composite entity exists only
if its components also exist, and therefore are in pure states.


title:
Vito Volterra and his commemoration for the centenary of Faraday's
  discovery of electromagnetic induction

abstract:
  The paper presents a memoir of 1931 written by Vito Volterra on the Italian
physicists of the nineteenth century and the researches these scientists made
after the discoveries of Michael Faraday on electromagnetism. Here, the memoir
entitled "I fisici italiani e le ricerche di Faraday" is translated from
Italian. It was written to commemorate the centenary of Faraday's discovery of
the electromagnetic induction. Besides being a remarkable article on the
history of science, it was also, in a certain extent, a political paper. In
fact, in 1931, the same year of the publication of this article, Mussolini
imposed a mandatory oath of loyalty to Italian academies. Volterra was one of
the very few professors who refused to take this oath of loyalty. Because of
the political situation in Italy, Volterra wanted to end his paper sending a
message to the scientists of the world, telling that the feeling of admiration
and gratitude that in Italy the scientists had towards "the great thinker and
British experimentalist" was profound and unanimous.


title:
RACE: A Rate Adaptive Channel Estimation Approach for Millimeter Wave
  MIMO Systems

abstract:
  In this paper, we consider the channel estimation problem in Millimeter wave
(mmWave) wireless systems with large antenna arrays. By exploiting the inherent
sparse nature of the mmWave channel, we develop a novel rate-adaptive channel
estimation (RACE) algorithm, which can adaptively adjust the number of required
channel measurements based on an expected probability of estimation error
(PEE). To this end, we design a maximum likelihood (ML) estimator to optimally
extract the path information and the associated probability of error from the
increasing number of channel measurements. Based on the ML estimator, the
algorithm is able to measure the channel using a variable number of beam
patterns until the receiver believes that the estimated direction is correct.
This is in contrast to the existing mmWave channel estimation algorithms, in
which the number of measurements is typically fixed. Simulation results show
that the proposed algorithm can significantly reduce the number of channel
estimation measurements while still retaining a high level of accuracy,
compared to existing multi-stage channel estimation algorithms.


title: Efficient Byzantine Sequential Change Detection

abstract:
  In the multisensor sequential change detection problem, a disruption occurs
in an environment monitored by multiple sensors. This disruption induces a
change in the observations of an unknown subset of sensors. In the Byzantine
version of this problem, which is the focus of this work, it is further assumed
that the postulated change-point model may be misspecified for an unknown
subset of sensors. The problem then is to detect the change quickly and
reliably, for any possible subset of affected sensors, even if the misspecified
sensors are controlled by an adversary. Given a user-specified upper bound on
the number of compromised sensors, we propose and study three families of
sequential change-detection rules for this problem. These are designed and
evaluated under a generalization of Lorden's criterion, where conditional
expected detection delay and expected time to false alarm are both computed in
the worst-case scenario for the compromised sensors. The first-order asymptotic
performance of these procedures is characterized as the worst-case false alarm
rate goes to 0. The insights from these theoretical results are corroborated by
a simulation study.


title:
Streda formula for the Hofstadter-Wilson-Dirac model in two and four
  dimensions

abstract:
  We rederive the spectral asymmetry of the Wilson-Dirac model in external
fields, paying attention to the Chern number due to the Berry connection. We
interpret the smooth part of the spectral asymmetry as the Streda formula that
is originally derived for the two-dimensional quantum Hall effect (QHE). We
show by numerical calculations that the Streda formula reproduces the known
first and second Chern numbers in a weak magnetic field limit. We conjecture
that the Streda formula is valid even for stronger fields and for more generic
systems in higher dimensions.


title: Functional renormalization group in Floquet space

abstract:
  We present an extension of the functional renormalization group to Floquet
space, which enables us to treat the long time behavior of interacting time
periodically driven quantum dots. It is one of its strength that the method is
neither bound to small driving amplitudes nor to small driving frequencies,
i.e. very general time periodic signals can be considered. It is applied to the
interacting resonant level model, a prototype model of a spinless, fermionic
quantum dot. The renormalization in several setups with different combinations
of time periodic parameters is studied, where the numerical results are
complemented by analytic expressions for the renormalization in the limit of
small driving amplitude. We show how the driving frequency acts as an infrared
cutoff of the underlying renormalization group flow which manifests in novel
power laws. We utilize the tunability of the effective reservoir distribution
function in a periodically driven onsite energy setup to show how its shape is
directly reflected in the renormalization group flow. This allows to flexibly
tune the power-law renormalization generically encountered in quantum dot
structures. Finally, an in-phase quantum pump as well as a single parameter
pump are investigated in the whole regime of driving frequency, demonstrating
that the new power law in the driving frequency is reflected in the mean
current of the latter.


title:
Machine Learning with Guarantees using Descriptive Complexity and SMT
  Solvers

abstract:
  Machine learning is a thriving part of computer science. There are many
efficient approaches to machine learning that do not provide strong theoretical
guarantees, and a beautiful general learning theory. Unfortunately, machine
learning approaches that give strong theoretical guarantees have not been
efficient enough to be applicable. In this paper we introduce a logical
approach to machine learning. Models are represented by tuples of logical
formulas and inputs and outputs are logical structures. We present our
framework together with several applications where we evaluate it using SAT and
SMT solvers. We argue that this approach to machine learning is particularly
suited to bridge the gap between efficiency and theoretical soundness. We
exploit results from descriptive complexity theory to prove strong theoretical
guarantees for our approach. To show its applicability, we present experimental
results including learning complexity-theoretic reductions rules for board
games. We also explain how neural networks fit into our framework, although the
current implementation does not scale to provide guarantees for real-world
neural networks.


title: The effects of dissipation on topological mechanical systems

abstract:
  We theoretically study the effects of isotropic dissipation in a topological
mechanical system which is an analogue of Chern insulator in mechanical
vibrational lattice. The global gauge invariance is still conserved in this
system albeit it is destroyed by the dissipation in the quantum counterpart.
The chiral edge states in this system are therefore robust against strong
dissipation. The dissipation also causes a dispersion of damping for the
eigenstates. It will modify the equation of motion of a wave packet by an extra
effective force. After taking into account the Berry curvature in the wave
vector space, the trace of a free wave packet in the real space should be
curved, feinting to break the Newton's first law.


title: Cosmological Perturbations in Restricted f(R)-Gravity

abstract:
  We investigate the metric perturbations of the restricted f(R) theory of
gravity in the cosmological context and explore the phenomenological
implications of this model. We show that it is possible to construct a
restricted model of gravity, in which the background equations are the same as
the equations of motion which are derived from the Einstein-Hilbert action with
the cosmological constant term. We argue that the deviation from the
Einstein-Hilbert model emerges in the perturbed equations, for which we have a
non-vanishing anisotropic stress. Further, with the help of the results of
Planck data for the modified gravity we obtain constraints on the parameters of
the model.


title:
SIGDROP: Signature-based ROP Detection using Hardware Performance
  Counters

abstract:
  Return-Oriented Programming (ROP) is a software exploit for system
compromise. By chaining short instruction sequences from existing code pieces,
ROP can bypass static code-integrity checking approaches and non-executable
page protections. Existing defenses either require access to source code or
binary, a customized compiler or hardware modifications, or suffer from high
performance and storage overhead. In this work, we propose SIGDROP, a low-cost
approach for ROP detection which uses low-level properties inherent to ROP
attacks. Specifically, we observe special patterns of certain hardware events
when a ROP attack occurs during program execution. Such hardware event-based
patterns form signatures to flag ROP attacks at runtime. SIGDROP leverages
Hardware Performance Counters, which are already present in commodity
processors, to efficiently capture and extract the signatures. Our evaluation
demonstrates that SIGDROP can effectively detect ROP attacks with acceptable
performance overhead and negligible storage overhead.


title: Optimal Speed Scaling with a Solar Cell

abstract:
  We consider the setting of a sensor that consists of a speed-scalable
processor, a battery, and a solar cell that harvests energy from its
environment at a time-invariant recharge rate. The processor must process a
collection of jobs of various sizes. Jobs arrive at different times and have
different deadlines. The objective is to minimize the *recharge rate*, which is
the rate at which the device has to harvest energy in order to feasibly
schedule all jobs. The main result is a polynomial-time combinatorial algorithm
for processors with a natural set of discrete speed/power pairs.


title: Correlation between social proximity and mobility similarity

abstract:
  Human behaviors exhibit ubiquitous correlations in many aspects, such as
individual and collective levels, temporal and spatial dimensions, content,
social and geographical layers. With rich Internet data of online behaviors
becoming available, it attracts academic interests to explore human mobility
similarity from the perspective of social network proximity. Existent analysis
shows a strong correlation between online social proximity and offline mobility
similari- ty, namely, mobile records between friends are significantly more
similar than between strangers, and those between friends with common neighbors
are even more similar. We argue the importance of the number and diversity of
com- mon friends, with a counter intuitive finding that the number of common
friends has no positive impact on mobility similarity while the diversity plays
a key role, disagreeing with previous studies. Our analysis provides a novel
view for better understanding the coupling between human online and offline
behaviors, and will help model and predict human behaviors based on social
proximity.


title:
Closed subgroups of the polynomial automorphism group containing the
  affine subgroup

abstract:
  We prove that, in characteristic zero, closed subgroups of the polynomial
automorphisms group containing the affine group contain the whole tame group.


title:
Peculiar Transverse Velocities of Galaxies from Quasar Microlensing.
  Tentative Estimate of the Peculiar Velocity Dispersion at $z\sim 0.5$

abstract:
  We propose to use the flux variability of lensed quasar images induced by
gravitational microlensing to measure the transverse peculiar velocity of lens
galaxies over a wide range of redshift. Microlensing variability is caused by
the motions of the observer, the lens galaxy (including the motion of the stars
within the galaxy), and the source; hence, its frequency is directly related to
the galaxy's transverse peculiar velocity. The idea is to count time-event
rates (e.g., peak or caustic crossing rates) in the observed microlensing light
curves of lensed quasars that can be compared with model predictions for
different values of the transverse peculiar velocity. To compensate for the
large time-scale of microlensing variability we propose to count and model the
number of events in an ensemble of gravitational lenses. We develop the
methodology to achieve this goal and apply it to an ensemble of 17 lensed
quasar systems. In spite of the shortcomings of the available data, we have
obtained tentative estimates of the peculiar velocity dispersion of lens
galaxies at $z\sim 0.5$, $\sigma_{\rm
pec}(0.53\pm0.18)\simeq(638\pm213)\sqrt{\langle m \rangle/0.3 M_\odot} \, \rm
km\, s^{-1}$. Scaling at zero redshift we derive, $\sigma_{\rm
pec}(0)\simeq(491\pm164) \sqrt{\langle m \rangle/0.3 M_\odot} \, \rm km\,
s^{-1}$, consistent with peculiar motions of nearby galaxies and with recent
$N$-body nonlinear reconstructions of the Local Universe based on $\Lambda$CDM.
We analyze the different sources of uncertainty of the method and find that for
the present ensemble of 17 lensed systems the error is dominated by Poissonian
noise, but that for larger ensembles the impact of the uncertainty on the
average stellar mass may be significant.


title: Measuring Player's Behaviour Change over Time in Public Goods Game

abstract:
  An important issue in public goods game is whether player's behaviour changes
over time, and if so, how significant it is. In this game players can be
classified into different groups according to the level of their participation
in the public good. This problem can be considered as a concept drift problem
by asking the amount of change that happens to the clusters of players over a
sequence of game rounds. In this study we present a method for measuring
changes in clusters with the same items over discrete time points using
external clustering validation indices and area under the curve. External
clustering indices were originally used to measure the difference between
suggested clusters in terms of clustering algorithms and ground truth labels
for items provided by experts. Instead of different cluster label comparison,
we use these indices to compare between clusters of any two consecutive time
points or between the first time point and the remaining time points to measure
the difference between clusters through time points. In theory, any external
clustering indices can be used to measure changes for any traditional
(non-temporal) clustering algorithm, due to the fact that any time point alone
is not carrying any temporal information. For the public goods game, our
results indicate that the players are changing over time but the change is
smooth and relatively constant between any two time points.


title: Chaoticons described by nonlocal nonlinear Schrodinger equation

abstract:
  It is shown that the unstable evolutions of the Hermite-Gauss-type stationary
solutions for the nonlocal nonlinear Schrodinger equation with the
exponential-decay response function can evolve into chaotic states. This new
kind of entities are referred to as chaoticons because they exhibit not only
chaotic properties (with positive Lyapunov exponents and spatial decoherence)
but also soliton-like properties (with invariant statistic width and
interaction of quasi-elastic collisions).


title:
Mutually unbiased maximally entangled bases in
  $\mathbb{C}^d\otimes\mathbb{C}^d$

abstract:
  We study mutually unbiased maximally entangled bases (MUMEB's) in bipartite
system $\mathbb{C}^d\otimes\mathbb{C}^d (d \geq 3)$. We generalize the method
to construct MUMEB's given in [16], by using any commutative ring $R$ with $d$
elements and generic character of $(R,+)$ instead of
$\mathbb{Z}_d=\mathbb{Z}/d\mathbb{Z}$. Particularly, if
$d=p_1^{a_1}p_2^{a_2}\ldots p_s^{a_s}$ where $p_1, \ldots, p_s$ are distinct
primes and $3\leq p_1^{a_1}\leq\cdots\leq p_s^{a_s}$, we present $p_1^{a_1}-1$
MUMEB's in $\mathbb{C}^d\otimes\mathbb{C}^d$ by taking
$R=\mathbb{F}_{p_1^{a_1}}\oplus\cdots\oplus\mathbb{F}_{p_s^{a_s}}$, direct sum
of finite fields (Theorem 3.3).


title:
Brueckner-Hartree-Fock and its renormalized calculations for finite
  nuclei

abstract:
  We have performed self-consistent Brueckner-Hartree-Fock (BHF) and its
renormalized theory to the structure calculations of finite nuclei. The
$G$-matrix is calculated within the BHF basis, and the exact Pauli exclusion
operator is determined by the BHF spectrum. Self-consistent occupation
probabilities are included in the renormalized Brueckner-Hartree-Fock (RBHF).
Various systematics and convergences are studies. Good results are obtained for
the ground-state energy and radius. RBHF can give a more reasonable
single-particle spectrum and radius. We present a first benchmark calculation
with other {\it ab initio} methods using the same effective Hamiltonian. We
find that the BHF and RBHF results are in good agreement with other $\it{ab}$
$\it{initio}$ methods.


title: Characterization of optical quantum circuits using resonant phase shifts

abstract:
  We demonstrate that important information about linear optical circuits can
be obtained through the phase shift induced by integrated optical resonators.
As a proof of principle, the phase of an unbalanced Mach-Zehnder interferometer
is determined. Then the method is applied to a complex optical circuit designed
for linear optical quantum computation. In this controlled-NOT gate with qubit
initialization and tomography stages, the relative phases are determined as
well as the coupling ratios of its directional couplers.


title: Killing Symmetry on Finsler Manifold

abstract:
  Killing vector fields $K$ are defined on Finsler manifold. The Killing
symmetry is reformulated simply as $\delta K^\flat =0$ by using the Killing
non-linear 1-form $K^\flat$ and the spray operator $\delta$ with the Finsler
non-linear connection. $K^\flat$ is related to the generalization of Killing
tensors on Finsler manifold, and the condition $\delta K^\flat =0$ gives an
analytical method of finding higher derivative conserved quantities, which may
be called hidden conserved quantities. We show two examples: the Carter
constant on Kerr spacetime and the Runge-Lentz vectors in Newtonian gravity.


title:
Identifying Topology of Power Distribution Networks Based on Smart Meter
  Data

abstract:
  In a power distribution network, the network topology information is
essential for an efficient operation of the network. This information of
network connectivity is not accurately available, at the low voltage level, due
to uninformed changes that happen from time to time. In this paper, we propose
a novel data--driven approach to identify the underlying network topology
including the load phase connectivity from time series of energy measurements.
The proposed method involves the application of Principal Component Analysis
(PCA) and its graph-theoretic interpretation to infer the topology from smart
meter energy measurements. The method is demonstrated through simulation on
randomly generated networks and also on IEEE recognized Roy Billinton
distribution test system.


title:
Origin of the low critical observing temperature of the quantum
  anomalous Hall effect in V-doped (Bi, Sb)2Te3 film

abstract:
  The experimental realization of the quantum anomalous Hall (QAH) effect in
magnetically-doped (Bi, Sb)2Te3 films stands out as a landmark of modern
condensed matter physics. However, ultra-low temperatures down to few tens of
mK are needed to reach the quantization of Hall resistance, which is two orders
of magnitude lower than the ferromagnetic phase transition temperature of the
films. Here, we systematically study the band structure of V-doped (Bi, Sb)2Te3
thin films by angle-resolved photoemission spectroscopy (ARPES) and show
unambiguously that the bulk valence band (BVB) maximum lies higher in energy
than the surface state Dirac point. Our results demonstrate clear evidence that
localization of BVB carriers plays an active role and can account for the
temperature discrepancy.


title: Schreier's formula for Prosupersolvable groups

abstract:
  We classify the finitely generated prosupersolvable groups that satisfy
Schreier's formula for the number of generators of open subgroups.


title:
A 5.4 Gbps real time quantum random number generator with compact
  implementation

abstract:
  We present a random number generation scheme based on measuring the phase
fluctuations of a laser with a simple and compact experimental setup. A simple
model is established to analyze the randomness and the simulation result based
on this model fits well with the experiment data. After the analog to digital
sampling and suitable randomness extraction integrated in the field
programmable gate array, the final random bits are delivered to a PC, realizing
a 5.4 Gbps real time quantum random number generation. The final random bit
sequences have passed all the NIST and DIEHARD tests.


title: Increasing Wireless Sensor Networks Lifetime with New Method

abstract:
  One of the most important issues in Wireless Sensor Networks (WSNs) is severe
energy restrictions. As the performance of Sensor Networks is strongly
dependence to the network lifetime, researchers seek a way to use node energy
supply effectively and increasing network lifetime. As a consequence, it is
crucial to use routing algorithms result in decrease energy consumption and
better bandwidth utilization. The purpose of this paper is to increase Wireless
Sensor Networks lifetime using LEACH-algorithm. So before clustering Network
environment, it is divided into two virtual layers (using distance between
sensor nodes and base station) and then regarding to sensors position in each
of two layers, residual energy of sensor and distance from base station is used
in clustering. In this article, we compare proposed algorithm with well-known
LEACH and ELEACH algorithms in homogeneous environment (with equal energy for
all sensors) and heterogeneous one (energy of half of sensors get doubled),
also for static and dynamic situation of base station. Results show that our
proposed algorithm delivers improved performance.


title:
The Fredrickson-Andersen model with random pinning on Bethe lattices and
  its MCT transitions

abstract:
  We investigate the dynamics of the randomly pinned Fredrickson-Andersen model
on the Bethe lattice. We find a line of random pinning dynamical transitions
whose dynamical critical properties are in the same universality class of the
$A_2$ and $A_3$ transitions of Mode Coupling Theory. The $A_3$ behavior appears
at the terminal point, where the relaxation becomes logarithmic and the
relaxation time diverges exponentially. We explain the critical behavior in
terms of self-induced disorder and avalanches, strengthening the relationship
discussed in recent works between glassy dynamics and Random Field Ising Model.


title:
A nonorthogonal state-interaction approach for matrix product state wave
  functions

abstract:
  We present a state-interaction approach for matrix product state (MPS) wave
functions in a nonorthogonal molecular orbital basis. Our approach allows us to
calculate for example transition and spin-orbit coupling matrix elements
between arbitrary electronic states provided that they share the same
one-electron basis functions and active orbital space, respectively. The key
element is the transformation of the MPS wave functions of different states
from a nonorthogonal to a biorthonormal molecular orbital basis representation
exploiting a sequence of non-unitary transformations following a proposal by
Malmqvist (Int. J. Quantum Chem. 30, 479 (1986)). This is well-known for
traditional wave-function parametrizations but has not yet been exploited for
MPS wave functions.

categories: physics.chem-ph cond-mat.str-el physics.comp-ph quant-ph


title: A 1-separably injective space that does not contain $\ell_\infty$

abstract:
  We show that the problem whether every $1$-separably injective Banach space
contains an isomorphic copy of $\ell_\infty$ is undecidable. Namely, unlike
under the continuum hypothesis, assuming Martin's axiom and the negation of the
continuum hypothesis, there is an $1$-separably injective Banach space of the
form $C(K)$ (which means that $K$ is an $F$-space) without an isomorphic copy
of $\ell_\infty$.
  This result is a consequence of our study of $\omega_2$-subsets of tightly
$\sigma$-filtered Boolean algebras introduced by Koppelberg for which we obtain
some general principles useful when transferring properties of Boolean algebras
to the level of Banach spaces.


title: Boosting Joint Models for Longitudinal and Time-to-Event Data

abstract:
  Joint Models for longitudinal and time-to-event data have gained a lot of
attention in the last few years as they are a helpful technique to approach
common a data structure in clinical studies where longitudinal outcomes are
recorded alongside event times. Those two processes are often linked and the
two outcomes should thus be modeled jointly in order to prevent the potential
bias introduced by independent modelling. Commonly, joint models are estimated
in likelihood based expectation maximization or Bayesian approaches using
frameworks where variable selection is problematic and which do not immediately
work for high-dimensional data. In this paper, we propose a boosting algorithm
tackling these challenges by being able to simultaneously estimate predictors
for joint models and automatically select the most influential variables even
in high-dimensional data situations. We analyse the performance of the new
algorithm in a simulation study and apply it to the Danish cystic fibrosis
registry which collects longitudinal lung function data on patients with cystic
fibrosis together with data regarding the onset of pulmonary infections. This
is the first approach to combine state-of-the art algorithms from the field of
machine-learning with the model class of joint models, providing a fully
data-driven mechanism to select variables and predictor effects in a unified
framework of boosting joint models.


title:
Extraction of Layout Entities and Sub-layout Query-based Retrieval of
  Document Images

abstract:
  Layouts and sub-layouts constitute an important clue while searching a
document on the basis of its structure, or when textual content is
unknown/irrelevant. A sub-layout specifies the arrangement of document entities
within a smaller portion of the document. We propose an efficient graph-based
matching algorithm, integrated with hash-based indexing, to prune a possibly
large search space. A user can specify a combination of sub-layouts of interest
using sketch-based queries. The system supports partial matching for
unspecified layout entities. We handle cases of segmentation pre-processing
errors (for text/non-text blocks) with a symmetry maximization-based strategy,
and accounting for multiple domain-specific plausible segmentation hypotheses.
We show promising results of our system on a database of unstructured entities,
containing 4776 newspaper images.


title:
A comparison of pivotal sampling and unequal probability sampling with
  replacement

abstract:
  We prove that any implementation of pivotal sampling is more efficient than
multinomial sampling. This property entails the weak consistency of the
Horvitz-Thompson estimator and the existence of a conservative variance
estimator. A small simulation study supports our findings.


title:
Quasi-periodic pulsations in solar and stellar flares: an overview of
  recent results

abstract:
  Quasi-periodic pulsations (or QPPs) are periodic intensity variations in the
flare emission, across all wavelength bands. In this paper, we review the
observational and modelling achievements since the previous review on this
topic by Nakariakov & Melnikov (2009). In recent years, it has become clear
that QPPs are an inherent feature of solar flares, because almost all flares
exhibit QPPs. Moreover, it is now firmly established that QPPs often show
multiple periods. We also review possible mechanisms for generating QPPs. Up to
now, it has not been possible to conclusively identify the triggering mechanism
or cause of QPPs. The lack of this identification currently hampers possible
seismological inferences of flare plasma parameters. QPPs in stellar flares
have been detected for a long time, and the high quality data of the Kepler
mission allows to study the QPP more systematically. However, it has not been
conclusively shown whether the time scales of stellar QPPs are different or the
same as those in solar flares.


title: Chiral oily streaks in a smectic-A liquid crystal

abstract:
  The liquid crystal octylcyanobiphenyl (8CB) was doped with the chiral agent
CB15 and spin-coated onto a substrate treated for planar alignment of the
director, resulting in a film of thickness several hundred nm in the smectic-A
phase. In both doped and undoped samples, the competing boundary conditions -
planar alignment at the substrate and vertical alignment at the free surface -
cause the liquid crystal to break into a series of flattened hemicylinders to
satisfy the boundary conditions. When viewed under an optical microscope with
crossed polarizers, this structure results in a series of dark and light
stripes ("oily streaks") of period ~ 1 $\mu$m. In the absence of chiral dopant
the stripes run perpendicular to the substrate's easy axis. However, when doped
with chiral CB15 at concentrations up to c = 4 wt-%, the stripe orientation
rotates by a temperature-dependent angle $\phi$ with respect to the c = 0
stripe orientation, where $\phi$ increases monotonically with c. $\phi$ is
largest just below the nematic -- smectic-A transition temperature TNA and
decreases with decreasing temperature. As the temperature is lowered, $\phi$
relaxes to a steady-state orientation close to zero within ~1$^\circ$ C of TNA.
We suggest that the rotation phenomenon is a manifestation of the surface
electroclinic effect: The rotation is due to the weak smectic order parameter
and resulting large director tilt susceptibility with respect to the smectic
layer normal near TNA, in conjunction with an effective surface electric field
due to polar interactions between the liquid crystal and substrate.


title:
H\"older estimates for fractional parabolic equations with critical
  divergence free drifts

abstract:
  This work focuses on drift-diffusion equations with fractional dissipation
$(-\Delta)^{\alpha}$ in the regime $\alpha \in (1/2,1)$. Our main result is an
a priori H\"older estimate on smooth solutions to the Cauchy problem, starting
from initial data with finite energy. We prove that for some $\beta \in (0,1)$,
the $C^{\beta}$ norm of the solution depends only on the size of the drift in
critical spaces of the form $L^{q}_{t}(BMO^{-\gamma}_{x})$ with $q>2$ and
$\gamma \in (0,2\alpha-1]$, along with the $L^{2}_{x}$ norm of the initial
datum. The proof uses the Caffarelli/Vasseur variant of De Giorgi's method for
non-local equations.


title: On the reachable set for the one-dimensional heat equation

abstract:
  The goal of this article is to provide a description of the reachable set of
the one-dimensional heat equation, set on the spatial domain x $\in$ (--L, L)
with Dirichlet boundary controls acting at both boundaries. Namely, in that
case, we shall prove that for any L0 \textgreater{} L any function which can be
extended analytically on the square {x + iy, |x| + |y| $\le$ L0} belongs to the
reachable set. This result is nearly sharp as one can prove that any function
which belongs to the reachable set can be extended analytically on the square
{x + iy, |x| + |y| \textless{} L}. Our method is based on a Carleman type
estimate and on Cauchy's formula for holomorphic functions.


title:
The effect of magnetic field on mean flow generation by rotating
  two-dimensional convection

abstract:
  Motivated by the significant interaction of convection, rotation and magnetic
field in many astrophysical objects, we investigate the interplay between
large-scale flows driven by rotating convection and an imposed magnetic field.
We utilise a simple model in two dimensions comprised of a plane layer that is
rotating about an axis inclined to gravity. It is known that this setup can
result in strong mean flows; we numerically examine the effect of an imposed
horizontal magnetic field on such flows. We show that increasing the field
strength in general suppresses the time-dependent mean flows, but in some cases
it organises them leading to stronger time-averaged flows. Further, we discuss
the effect of the field on the correlations responsible for driving the flows
and the competition between Reynolds and Maxwell stresses. A change in
behaviour is observed when the (fluid and magnetic) Prandtl numbers are
decreased. In the smaller Prandtl number regime, it is shown that significant
mean flows can persist even when the quenching of the overall flow velocity by
the field is relatively strong.


title:
Optimal Self-Stabilizing Mobile Byzantine-Tolerant Regular Register with
  bounded timestamp

abstract:
  This paper proposes the first implementation of a self-stabilizing regular
register emulated by $n$ servers that is tolerant to both mobile Byzantine
agents, and \emph{transient failures} in a round-free synchronous model.
Differently from existing Mobile Byzantine tolerant register implementations,
this paper considers a more powerful adversary where (i) the message delay
(i.e., $\delta$) and the period of mobile Byzantine agents movement (i.e.,
$\Delta$) are completely decoupled and (ii) servers are not aware of their
state i.e., they do not know if they have been corrupted or not by a mobile
Byzantine agent.The proposed protocol tolerates \emph{(i)} any number of
transient failures, and \emph{(ii)} up to $f$ Mobile Byzantine agents. In
addition, our implementation uses bounded timestamps from the
$\mathcal{Z}\_{13}$ domain and it is optimal with respect to the number of
servers needed to tolerate $f$ mobile Byzantine agents in the given model.


title:
Manifolds of low dimension with trivial canonical bundle in
  Grassmannians

abstract:
  We study fourfolds with trivial canonical bundle which are zero loci of
sections of homogeneous, completely reducible bundles over ordinary and
classical complex Grassmannians. We prove that the only HyperK{\"a}hler
fourfolds among them are the example of Beauville and Donagi, and the example
of Debarre and Voisin. In doing so, we give a complete classification of those
varieties. We include also the analogous classification for surfaces and
threefolds.


title:
Bayesian Quantile-Based Joint Modelling of Repeated Measurement and
  Time-to-Event data, with an Application to Lung Function Decline and Time to
  Infection in Patients with Cystic Fibrosis

abstract:
  Background: The most widely used approach to joint modelling of repeated
measurement and time to event data is to combine a linear Gaussian random
effects model for the repeated measurements with a log-Gaussian frailty model
for the time-to-event outcome, linking the two through some form of correlation
structure between the random effects and the log-frailty. In this approach,
covariates are assumed to affect the mean response profile of the repeated
measurement data. Objectives: Some applications raise substantive questions
that cannot be captured by this structure. For example, an important question
in cystic fibrosis (CF) research is to understand the impact of a patient's
lung function trajectory on their risk of acquiring a variety of infections,
and how this varies at different quantiles of the lung function distribution.
Methods: Motivated by this question, we develop a joint quantile modelling
framework in this paper with an associated Markov Chain Monte Carlo algorithm
for Bayesian inference. Results: The translation from the common joint model
towards quantile regression succeeds and is applied to CF data from the United
Kingdom. The method helps detecting an overall difference in the relation
between lung function decline and onset of infection in the different
quantiles. Conclusions: Joint modelling without taking into account the special
heteroscedastic structure is not sufficient in certain research question and
the extensions towards models beyond the mean is necessary.


title:
Randomized filtering and Bellman equation in Wasserstein space for
  partial observation control problem

abstract:
  We study a stochastic optimal control problem for a partially observed
diffusion. By using the control randomization method in [4], we prove a
corresponding randomized dynamic programming principle (DPP) for the value
function, which is obtained from a flow property of an associated filter
process. This DPP is the key step towards our main result: a characterization
of the value function of the partial observation control problem as the unique
viscosity solution to the corresponding dynamic programming
Hamilton-Jacobi-Bellman (HJB) equation. The latter is formulated as a new,
fully non linear partial differential equation on the Wasserstein space of
probability measures. An important feature of our approach is that it does not
require any non-degeneracy condition on the diffusion coefficient, and no
condition is imposed to guarantee existence of a density for the filter process
solution to the controlled Zakai equation, as usually done for the separated
problem. Finally, we give an explicit solution to our HJB equation in the case
of a partially observed non Gaussian linear quadratic model.


title: A Time scales Noether's theorem

abstract:
  We prove a time scales version of the Noether's theorem relating group of
symmetries and conservation laws. Our result extends the continuous version of
the Noether's theorem as well as the discrete one and corrects a previous
statement of Bartosiewicz and Torres in \cite{BT}.


title:
Mesoscopic fluctuations of the single-particle Green's function at
  Anderson transitions with Coulomb interaction

abstract:
  Using the two-loop analysis and the background field method we demonstrate
that the local pure scaling operators without derivatives in the Finkel'stein
nonlinear sigma model can be constructed by straightforward generalization of
the corresponding operators for the noninteracting case. These pure scaling
operators demonstrate multifractal behavior and describe mesoscopic
fluctuations of the single-particle Green's function. We determine anomalous
dimensions of all such pure scaling operators in the interacting theory within
the two-loop approximation.


title:
Efficient batch-sequential Bayesian optimization with moments of
  truncated Gaussian vectors

abstract:
  We deal with the efficient parallelization of Bayesian global optimization
algorithms, and more specifically of those based on the expected improvement
criterion and its variants. A closed form formula relying on multivariate
Gaussian cumulative distribution functions is established for a generalized
version of the multipoint expected improvement criterion. In turn, the latter
relies on intermediate results that could be of independent interest concerning
moments of truncated Gaussian vectors. The obtained expansion of the criterion
enables studying its differentiability with respect to point batches and
calculating the corresponding gradient in closed form. Furthermore , we derive
fast numerical approximations of this gradient and propose efficient batch
optimization strategies. Numerical experiments illustrate that the proposed
approaches enable computational savings of between one and two order of
magnitudes, hence enabling derivative-based batch-sequential acquisition
function maximization to become a practically implementable and efficient
standard.


title:
Orbital-selective single molecule excitation and spectroscopy based on
  plasmon-exciton coupling

abstract:
  The electronic excitation of molecules triggers diverse phenomena such as
luminescence and photovoltaic effects, which are the bases of various
energy-converting devices. Understanding and control of the excitations at the
single-molecule level are long standing targets, however, they have been
hampered by the limited spatial resolution in optical probing techniques. Here
we investigate the electronic excitation of a single molecule with
sub-molecular precision using a localised plasmon at the tip apex of a scanning
tunnelling microscope (STM) as an excitation probe. Coherent energy transfer
between the plasmon and molecular excitons is discovered when the plasmon is
located in the proximity of isolated molecules, which is corroborated by a
theoretical analysis. The polarised plasmonic field enables selective
excitation of an electronic transition between anisotropic frontier molecular
orbitals. Our findings have established the foundation of a novel
single-molecule spectroscopy with STM, providing an integrated platform for
real-space investigation of localised excited states.


title: The discrete centroaffine indefinite surface

abstract:
  In this paper we build the structure equations and the integrable systems for
a discrete centroaffine indefinite surface in $\R^3$. At the same time, some
centroaffine invariants are obtained according to the structure equations.
Using these centroaffine invariants, we study the Laplacian operator and the
convexity of a discrete centroaffine indefinite surface. Furthermore, some
interest examples are provided.


title:
Confidence and efficiency scaling in Variational Quantum Monte Carlo
  calculations

abstract:
  Based on the central limit theorem, we discuss the problem of evaluation of
the statistical error of Monte Carlo calculations using a time discretized
diffusion process. We present a robust and practical method to determine the
effective variance of general observables and show how to verify the
equilibrium hypothesis by the Kolmogorov-Smirnov test. We then derive scaling
laws of the efficiency illustrated by Variational Monte Carlo calculations on
the two dimensional electron gas.


title: The construction of all the projective spanning trees of a given digraph

abstract:
  In the present paper we consider the problem of constructing all the
projective rooted spanning trees of a given graph. We propose an algorithm
based on reducing this problem to the problem of constructing all the maximal
independent sets of a certain derived graph. We also offer an algorithm for
step-by-step growing the spanning trees that sifts, at each step, any sub-trees
non-extendable to projective spanning trees. The proposed algorithms were
applied for analyzing the possible variants of the syntactic subordination of
nouns through prepositions .


title:
An analogue of the Coleman-Mandula theorem for quantum field theory in
  curved spacetimes

abstract:
  The Coleman-Mandula (CM) theorem states that the Poincar\'e and internal
symmetries of a Minkowski spacetime quantum field theory cannot combine
nontrivially in an extended symmetry group. We establish an analogous result
for quantum field theory in curved spacetimes, assuming local covariance, the
timeslice property, a local dynamical form of Lorentz invariance, and
additivity. Unlike the CM theorem, our result is valid in dimensions $n\ge 2$
and for free or interacting theories. It is formulated for theories defined on
a category of all globally hyperbolic spacetimes equipped with a global
coframe, on which the restricted Lorentz group acts, and makes use of a general
analysis of symmetries induced by the action of a group $G$ on the category of
spacetimes. Such symmetries are shown to be canonically associated with a
cohomology class in the second degree nonabelian cohomology of $G$ with
coefficients in the global gauge group of the theory. Our main result proves
that the cohomology class is trivial if $G$ is the universal cover $\cal S$ of
the restricted Lorentz group. Among other consequences, it follows that the
extended symmetry group is a direct product of the global gauge group and $\cal
S$, all fields transform in multiplets of $\cal S$, fields of different spin do
not mix under the extended group, and the occurrence of noninteger spin is
controlled by the centre of the global gauge group. The general analysis is
also applied to rigid scale covariance.


title: Modeling of deep gaps created by giant planets in protoplanetary discs

abstract:
  A giant planet embedded in a protoplanetary disk creates a gap. This process
is important for both theory and observations. Using results of a survey for a
wide parameter range with two-dimensional hydrodynamic simulations, we
constructed an empirical formula for the gap structure (i.e., the radial
surface density distribution), which can reproduce the gap width and depth
obtained by two-dimensional simulations. This formula enables us to judge
whether an observed gap is likely to be caused by an embedded planet or not.
The propagation of waves launched by the planet is closely connected to the gap
structure. It makes the gap wider and shallower as compared with the case where
an instantaneous wave damping is assumed. The hydrodynamic simulations shows
that the waves do not decay immediately at the launching point of waves, even
when the planet is as massive as Jupiter. Based on the results of hydrodynamic
simulations, we also obtained an empirical model of wave propagation and
damping for the cases of deep gaps. The one-dimensional gap model with our wave
propagation model is able to well reproduce the gap structures in hydrodynamic
simulations. In the case of a Jupiter-mass planet, we also found that the waves
with smaller wavenumber (e.g., $m=2$) are excited and transport the angular
momentum to the location far away from the planet. The wave with $m=2$ is
closely related with a secondary wave launched by the site opposite from the
planet.


title: The approximation property and Lipschitz mappings on Banach spaces

abstract:
  We present an overview to the approximation property, paying especial
attention to the recent results relating the approximation property to ideals
of linear operators and Lipschitz ideals.
  We complete the paper with some new results on approximation of Lipschitz
mappings and their relation to linear operator ideals.


title: Hyperon star in a modified quark meson coupling model

abstract:
  We determine the equation of state (EOS) of nuclear matter with the inclusion
of hyperons in a self-consistent manner by using a Modified Quark Meson
Coupling Model (MQMC) where the confining interaction for quarks inside a
baryon is represented by a phenomenological average potential in an equally
mixed scalar-vector harmonic form. The hadron-hadron interaction in nuclear
matter is then realized by introducing additional quark couplings to $\sigma$,
$\omega$, and $\rho$ mesons through mean-field approximations. The effect of a
nonlinear $\omega$-$\rho$ term on the equation of state is studied. The hyperon
couplings are fixed from the optical potential values and the mass-radius curve
is determined satisfying the maximum mass constraint of $2$~M$_{\odot}$ for
neutron stars, as determined in recent measurements of the pulsar PSR
J0348+0432. We also observe that there is no significant advantage of
introducing the nonlinear $\omega$-$\rho$ term in the context of obtaining the
star mass constraint in the present set of parametrizations.


title:
Some inclusion results for interpolated summing operator ideals and
  integrability improvement of vector valued functions

abstract:
  Consider a Banach space valued measurable function $f$ and an operator $u$
from the space where {$f$} takes values. If $f $ is Pettis integrable, a
classical result due to J. Diestel shows that composing it with $u$ gives a
Bochner integrable function $u \circ f$ whenever $u$ is absolutely summing. In
a previous work we have shown that a well-known interpolation technique for
operator ideals allows to prove under some requirements that a composition of a
$p$-Pettis integrable function with a $q$-summing operator provides an
$r$-Bochner integrable function. In this paper a new abstract inclusion theorem
for classes of {abstract} summing operators is shown and applied to the class
of interpolated operator ideals. Together with the results of the
{aforementioned} paper, it provides more results on the relation about the
integrability of the function $u \circ f$ and the summability properties of
$u$.


title:
A brief history of the solar diameter measurements: a critical quality
  assessment of the existing data

abstract:
  The size of the diameter of the Sun has been debated for a very long time.
First tackled by the Greek astronomers from a geometric point of view, an
estimate, although incorrect, has been determined, not truly called into
question for several centuries. The French school of astronomy, under the
impetus of Mouton and Picard in the XVIIth century can be considered as a
pioneer in this issue. It was followed by the German school at the end of the
XIXth century whose works led to a canonical value established at 959".63
(second of arc). A number of ground-based observations has been made in the
second half of the XIXth century leading to controversial results mainly due to
the difficulty to disentangle between the solar and atmospheric effects.
Dedicated space measurements yield to a very faint dependence of the solar
diameter with time. New studies over the entire radiation spectrum lead to a
clear relationship between the solar diameter and the wavelength, reflecting
the height at which the lines are formed. Thus the absolute value of the solar
diameter, which is a reference for many astrophysical applications, must be
stated according to the wavelength. Furthermore, notable features of the Near
Sub-Surface Layer (NSSL), called the leptocline, can be established in relation
to the solar limb variations, mainly through the shape asphericities
coefficients. The exact relationship has not been established yet, but recent
studies encourage further in-depth investigations of the solar subsurface
dynamics, both observationally and by numerical MHD simulations.


title:
Parametrization of Minimal Spectral Factors of Discrete-Time Rational
  Spectral Densities

abstract:
  In this paper, the problem of providing a complete parametrization of the
minimal spectral factors of a discrete-time rational spectral density is
considered. The desired parametrization, given in terms of the all-pass
divisors of a certain all-pass function, is established in the most general
setting: after several partial results, mostly in the continuous-time case,
this is indeed the first complete parametrization obtained without resorting to
any facilitating assumption. This result provides a positive answer to a
conjecture raised in [Baggio and Ferrante, 2016].


title:
$J/\psi N$ interactions revisited and $\Lambda_b^0 \to J/\psi K^-
  (\pi^-) p$ decays

abstract:
  Recently LHCb experiments confirmed the findings of the two $P_c$ states in
the $\Lambda_b^0 \to J/\psi p \pi^-$ decays. In the present work, we
investigate both the $\Lambda_b^0 \to J/\psi K^- p$ and the $\Lambda_b^0 \to
J/\psi p \pi^-$ decays, continuing the investigations of our former works on
the interactions of $J/\psi N$ with its coupled channels by considering the
s-/u- channel contributions. We obtain consistent results of the line-shape of
the $J/\psi N$ invariant mass distribution with the LHCb experiments, and
favour the $P_c (4450)$ state as a $\bar{D}^* \Sigma_c$ bound state with
$J=1/2^-$.


title:
Investigating Energetic X-Shaped Flares on the Outskirts of A Solar
  Active Region

abstract:
  Typical solar flares display two quasi-parallel, bright ribbons on the
chromosphere. In between is the polarity inversion line (PIL) separating
concentrated magnetic fluxes of opposite polarity in active regions (ARs).
Intriguingly a series of flares exhibiting X-shaped ribbons occurred at the
similar location on the outskirts of NOAA AR 11967, where magnetic fluxes were
scattered, yet three of them were alarmingly energetic. The X shape, whose
center coincided with hard X-ray emission, was similar in UV/EUV, which cannot
be accommodated in the standard flare model. Mapping out magnetic
connectivities in potential fields, we found that the X morphology was dictated
by the intersection of two quasi-separatrix layers, i.e., a hyperbolic flux
tube (HFT), within which a separator connecting a double null was embedded.
This topology was not purely local but regulated by fluxes and flows over the
whole AR. The nonlinear force-free field model suggested the formation of a
current layer at the HFT, where the current dissipation can be mapped to the
X-shaped ribbons via field-aligned heat conduction. These results highlight the
critical role of HFTs in 3D magnetic reconnection and have important
implications for astrophysical and laboratory plasmas.


title: Bruhat order and nil-Hecke algebras for Weyl groupoids

abstract:
  We introduce nil-Hecke algebras for Weyl groupoids. We describe a basis and
some properties of these algebras which lead to a notion of Bruhat order for
Weyl groupoids.


title: Automatic Selection of Stochastic Watershed Hierarchies

abstract:
  The segmentation, seen as the association of a partition with an image, is a
difficult task. It can be decomposed in two steps: at first, a family of
contours associated with a series of nested partitions (or hierarchy) is
created and organized, then pertinent contours are extracted. A coarser
partition is obtained by merging adjacent regions of a finer partition. The
strength of a contour is then measured by the level of the hierarchy for which
its two adjacent regions merge. We present an automatic segmentation strategy
using a wide range of stochastic watershed hierarchies. For a given set of
homogeneous images, our approach selects automatically the best hierarchy and
cut level to perform image simplification given an evaluation score.
Experimental results illustrate the advantages of our approach on several
real-life images datasets.


title: Automorphisms of minimal entropy on supersingular K3 surfaces

abstract:
  In this article we give a strategy to decide whether the logarithm of a given
Salem number is realized as entropy of an automorphism of a supersingular K3
surface in positive characteristic. As test case it is proved that $\log
\lambda_d$, where $\lambda_d$ is the minimal Salem number of degree $d$, is
realized in characteristic $5$ if and only if $d\leq 22$ is even and $d\neq
18$.
  In the complex projective setting we settle the case of entropy $\log
\lambda_{12}$ left open by McMullen, by giving the construction. A necessary
and sufficient test is developed to decide whether a given isometry of a
hyperbolic lattice, with spectral radius bigger than one, is positive, i.e.
preserves a chamber of the positive cone.


title: Dynamics of post-critically finite maps in higher dimension

abstract:
  We study the dynamics of post-critically finite endomorphisms of P^k(C). We
prove that post-critically finite endomorphisms are always post-critically
finite all the way down under a mild regularity condition on the post-critical
set. We study the eigenvalues of periodic points of post-critically finite
endomorphisms. Then, under a weak transversality condition and assuming
Kobayashi hyperbolicity of the complement of the post-critical set, we prove
that the only possible Fatou components are super-attracting basins, thus
partially extending to any dimension a result of Fornaess-Sibony and Rong
holding in the case k = 2.