title: Mixed metric dimension of graphs

abstract:
  Let $G=(V,E)$ be a connected graph. A vertex $w\in V$ distinguishes two
elements (vertices or edges) $x,y\in E\cup V$ if $d_G(w,x)\ne d_G(w,y)$. A set
$S$ of vertices in a connected graph $G$ is a mixed metric generator for $G$ if
every two elements (vertices or edges) of $G$ are distinguished by some vertex
of $S$. The smallest cardinality of a mixed metric generator for $G$ is called
the mixed metric dimension and is denoted by $\mathrm{mdim}(G)$. In this paper
we consider the structure of mixed metric generators and characterize graphs
for which the mixed metric dimension equals the trivial lower and upper bounds.
We also give results about the mixed metric dimension of some families of
graphs and present an upper bound with respect to the girth of a graph.
Finally, we prove that the problem of determining the mixed metric dimension of
a graph is NP-hard in the general case.


title: A Mathematic Expression of the Genes of Chinese Traditional Philosophy

abstract:
  We provide a mathematic model for the Traditional Yin-and-Yang Double Fish
Diagram which from Chinese Traditional Philosophy.


title: Eisenhart lift for higher derivative systems

abstract:
  The Eisenhart lift provides an elegant geometric description of a dynamical
system of second order in terms of null geodesics of the Brinkmann-type metric.
In this work, we attempt to generalize the Eisenhart method so as to encompass
higher derivative models. The analysis relies upon Ostrogradsky's Hamiltonian.
A consistent geometric description seems feasible only for a particular class
of potentials. The scheme is exemplified by the Pais-Uhlenbeck oscillator.


title: The parameters uncertainty inflation fallacy

abstract:
  Statistical estimation of the prediction uncertainty of physical models is
typically hindered by the inadequacy of these models due to various
approximations they are built upon. The prediction errors due to model
inadequacy can be handled either by correcting the model's results, or by
adapting the model's parameters uncertainty to generate prediction uncertainty
representative, in a way to be defined, of model inadequacy errors. The main
advantage of the latter approach is its transferability to the prediction of
other quantities of interest based on the same parameters. A critical review of
state-of-the-art implementations of this approach in computational chemistry
shows that it is biased, in the sense that it does not produce prediction
uncertainty bands conforming with model inadequacy errors.


title:
Isothermal Entropy Change and Adiabatic Change of Temperature of the
  Antiferromagnetic Spin-1/2 Ising Octahedron and Dodecahedron

abstract:
  The spin-1/2 Ising octahedron and dodecahedron with a unique
antiferromagnetic interaction display an outstanding magnetization jump at zero
magnetic field, which consequently leads to a giant magnetocaloric effect
during the adiabatic demagnetization. In the present work we report temperature
dependences of two basic magnetocaloric response functions: the isothermal
entropy change and the adiabatic change of temperature. It is shown that the
Ising octahedron and dodecahedron generally exhibit a large negative isothermal
entropy change upon increasing of the magnetic field, which serves in evidence
of their cooling performance.


title: Baryon-to-meson transition distribution amplitudes: formalism and models

abstract:
  In specific kinematics, hard exclusive amplitudes may be factorized into a
short distance dominated part computable in a perturbative way on the one hand,
and universal, confinement related hadronic matrix elements on the other hand.
The extension of this description to processes such as backward meson
electroproduction and forward meson production in antiproton-nucleon scattering
leads to define new hadronic matrix elements of three quark operators on the
light cone, the nucleon-to-meson transition distribution amplitudes, which shed
a new light on the nucleon structure.


title: A DNN Framework For Text Image Rectification From Planar Transformations

abstract:
  In this paper, a novel neural network architecture is proposed attempting to
rectify text images with mild assumptions. A new dataset of text images is
collected to verify our model and open to public. We explored the capability of
deep neural network in learning geometric transformation and found the model
could segment the text image without explicit supervised segmentation
information. Experiments show the architecture proposed can restore planar
transformations with wonderful robustness and effectiveness.


title:
Systematic effects in the measurement of the negatively charged pion
  mass using laser spectroscopy of pionic helium atoms

abstract:
  The collision-induced shift and broadening of selected dipole transition
lines of pionic helium in gaseous helium at low temperatures up to $T=12$ K and
pressure up to a few bar are calculated within variable phase function
approach. We predict blue shift of the resonance frequencies of the
$(n,l)=(16,15) \rightarrow (16,14) $ and $(16,15) \rightarrow (17,14)$
unfavored transitions and red shift for the favored transition $(17,16)
\rightarrow (16,15)$. The result may be helpful in reducing the systematic
error in proposed future experiments for determination of the negatively
charged pion mass from laser spectroscopy of metastable pionic helium atoms.


title: Modelling laser-atom interactions in the strong field regime

abstract:
  We consider the ionisation of atomic hydrogen by a strong infrared field. We
extend and study in more depth an existing semi-analytical model. Starting from
the time-dependent Schroedinger equation in momentum space and in the velocity
gauge we substitute the kernel of the non-local Coulomb potential by a sum of N
separable potentials, each of them supporting one hydrogen bound state. This
leads to a set of N coupled one-dimensional linear Volterra integral equations
to solve. We analyze the gauge problem for the model, the different ways of
generating the separable potentials and establish a clear link with the strong
field approximation which turns out to be a limiting case of the present model.
We calculate electron energy spectra as well as the time evolution of electron
wave packets in momentum space. We compare and discuss the results obtained
with the model and with the strong field approximation and examine in this
context, the role of excited states.


title:
Magnetization process and magnetocaloric effect of the spin-1/2 XXZ
  Heisenberg cuboctahedron

abstract:
  Magnetic properties of the spin-1/2 XXZ Heisenberg cuboctahedron are examined
using exact numerical diagonalization depending on a relative strength of the
exchange anisotropy. While the Ising cuboctahedron exhibits in a
low-temperature magnetization curve only one-third magnetization plateau, the
XXZ Heisenberg cuboctahedron displays another four intermediate plateaux at
zero, one-sixth, one-half and two-thirds of the saturation magnetization. The
novel magnetization plateaux generally extend over a wider range of magnetic
fields with increasing of a quantum ($xy$) part of the XXZ exchange
interaction. It is shown that the XXZ Heisenberg cuboctahedron exhibits in a
vicinity of all magnetization jumps anomalous thermodynamic behavior
accompanied with an enhanced magnetocaloric effect.


title:
Observation of Ultrahigh Mobility Surface States in a Topological
  Crystalline Insulator by Infrared Spectroscopy

abstract:
  Topological crystalline insulators (TCIs) possess metallic surface states
protected by crystalline symmetry, which are a versatile platform for exploring
topological phenomena and potential applications. However, progress in this
field has been hindered by the challenge to probe optical and transport
properties of the surface states owing to the presence of bulk carriers. Here
we report infrared (IR) reflectance measurements of a TCI, (001) oriented
$Pb_{1-x}Sn_{x}Se$ in zero and high magnetic fields. We demonstrate that the
far-IR conductivity is unexpectedly dominated by the surface states as a result
of their unique band structure and the consequent small IR penetration depth.
Moreover, our experiments yield a surface mobility of 40000 $cm^{2}/(Vs)$,
which is one of the highest reported values in topological materials,
suggesting the viability of surface-dominated conduction in thin TCI crystals.
These findings pave the way for exploring many exotic transport and optical
phenomena and applications predicted for TCIs.


title: Chromatic polynomials and bialgebras of graphs

abstract:
  The chromatic polynomial is characterized as the unique polynomial invariant
of graphs, compatible with two interacting bialgebras structures: the first
coproduct is given by partitions of vertices into two parts, the second one by
a contraction-extraction process. This gives Hopf-algebraic proofs of Rota's
result on the signs of coefficients of chromatic polynomials and of Stanley's
interpretation of the values at negative integers of chromatic polynomi-als. We
also give non-commutative version of this construction, replacing graphs by
indexed graphs and Q[X] by the Hopf algebra WSym of set partitions.


title:
The strong field approximation within a Faddeev-like formalism for
  laser-matter interactions

abstract:
  We consider the interaction of atomic hydrogen with an intense laser field
within the strong-field approximation. By using a Faddeev-like formalism, we
introduce a new perturbative series in the binding potential of the atom. As a
first test of this new approach, we calculate the electron energy spectrum in
the very simple case of a photon energy higher than the ionisation potential.
We show that by contrast to the standard perturbative series in the binding
potential obtained within the strong field approximation, the first terms of
the new series converge rapidly towards the results we get by solving the
corresponding time-dependent Schroedinger equation.


title: Well-posedness of the Green-Naghdi and Boussinesq-Peregrine systems

abstract:
  In this paper we address the Cauchy problem for two systems modeling the
propagation of long gravity waves in a layer of homogeneous, incompressible and
inviscid fluid delimited above by a free surface, and below by a
non-necessarily flat rigid bottom. Concerning the Green-Naghdi system, we
improve the result of Alvarez-Samaniego and Lannes (Invent. Math., 2008) in the
sense that much less regular data are allowed, and no loss of derivatives is
involved. Concerning the Boussinesq-Peregrine system, we improve the lower
bound on the time of existence provided by M{\'e}sognon-Gireau (Adv.
Differential Equations, 2017). The main ingredient is a physically motivated
change of unknowns revealing the quasilinear structure of the systems, from
which energy methods are implemented.


title: A new family of Poisson algebras and their deformations

abstract:
  Let $\Bbbk$ be a field of characteristic zero. For any positive integer $n$
and any scalar $a\in\Bbbk$, we construct a family of Artin-Schelter regular
algebras $R(n,a)$, which are quantisations of Poisson structures on
$\Bbbk[x_0,\dots,x_n]$. This generalises an example given by Pym when $n=3$.
For a particular choice of the parameter $a$ we obtain new examples of
Calabi-Yau algebras when $n\geq 4$. We also study the ring theoretic properties
of the algebras $R(n,a)$. We show that the point modules of $R(n,a)$ are
parameterised by a bouquet of rational normal curves in $\mathbb{P}^{n}$, and
that the prime spectrum of $R(n,a)$ is homeomorphic to the Poisson spectrum of
its semiclassical limit. Moreover, we explicitly describe ${\rm Spec}\ R(n,a)$
as a union of commutative strata.


title: Theory of Laser-Controlled Competing Superconducting and Charge Orders

abstract:
  We investigate the nonequilibrium dynamics of competing coexisting
superconducting (SC) and charge-density wave (CDW) orders in an attractive
Hubbard model. A time-periodic laser field $\vec{A}(t)$ lifts the SC-CDW
degeneracy, since the CDW couples linearly to the field ($\vec{A}$), whereas SC
couples in second order ($\vec{A}^2$) due to gauge invariance. This leads to a
striking resonance: When the photon energy is red-detuned compared to the
equilibrium single-particle energy gap, CDW is enhanced and SC is suppressed,
while this behavior is reversed for blue detuning. Both orders oscillate with
an emergent slow frequency, which is controlled by the small amplitude of a
third induced order, namely $\eta$ pairing, given by the commutator of the two
primary orders. The induced $\eta$ pairing is shown to control the enhancement
and suppression of the dominant orders. Finally, we demonstrate that
light-induced superconductivity is possible starting from a predominantly CDW
initial state.


title: Uncertain Graph Sparsification

abstract:
  Uncertain graphs are prevalent in several applications including
communications systems, biological databases and social networks. The ever
increasing size of the underlying data renders both graph storage and query
processing extremely expensive. Sparsification has often been used to reduce
the size of deterministic graphs by maintaining only the important edges.
However, adaptation of deterministic sparsification methods fails in the
uncertain setting. To overcome this problem, we introduce the first
sparsification techniques aimed explicitly at uncertain graphs. The proposed
methods reduce the number of edges and redistribute their probabilities in
order to decrease the graph size, while preserving its underlying structure.
The resulting graph can be used to efficiently and accurately approximate any
query and mining tasks on the original graph. An extensive experimental
evaluation with real and synthetic datasets illustrates the effectiveness of
our techniques on several common graph tasks, including clustering coefficient,
page rank, reliability and shortest path distance.


title:
Constraining a variable dark energy model from the redshift-luminosity
  distance relations of gamma-ray bursts and type Ia supernovae

abstract:
  There are many kinds of models which describe the dynamics of dark energy
(DE). Among all we adopt an equation of state (EoS) which varies as a function
of time. We adopt Markov Chain Monte Carlo method to constrain the five
parameters of our models. As a consequence, we can show the characteristic
behavior of DE during the evolution of the universe. We constrain the EoS of DE
with use of the avairable data of gamma-ray bursts and type Ia supernovae (SNe
Ia) concerning the redshift-luminosity distance relations. As a result, we find
that DE is quintessence-like in the early time and phantom-like in the present
epoch or near the future, where the change occurs rather rapidly at $z\sim0.3$.


title:
Measurement of the ratio h/e with a photomultiplier tube and a set of
  LEDs

abstract:
  We propose a laboratory experience aimed at undergraduate physics students to
understand the main features of the photoelectric effect and to perform a
measurement of the ratio h/e, where h is the Planck's constant and e is the
electron charge. The experience is based on the method developed by Millikan
for his measurements on the photoelectric effect in the years from 1912 to
1915. The experimental setup consists of a photomultiplier tube (PMT) equipped
with a voltage divider properly modified to set variable retarding potentials
between the photocathode and the first dynode, and a set of LEDs emitting at
different wavelengths. The photocathode is illuminated with the various LEDs
and, for each wavelength of the incident light, the output anode current is
measured as a function of the retarding potential applied between the cathode
and the first dynode. From each measurement, a value of the stopping potential
for the anode current is derived. Finally, the stopping potentials are plotted
as a function of the frequency of the incident light, and a linear fit is
performed. The slope and the intercept of the line allow respectively to
evaluate the ratio h/e and the ratio W/e, where W is the work function of the
photocathode.


title:
How the interbank market becomes systemically dangerous: an agent-based
  network model of financial distress propagation

abstract:
  Assessing the stability of economic systems is a fundamental research focus
in economics, that has become increasingly interdisciplinary in the currently
troubled economic situation. In particular, much attention has been devoted to
the interbank lending market as an important diffusion channel for financial
distress during the recent crisis. In this work we study the stability of the
interbank market to exogenous shocks using an agent-based network framework.
Our model encompasses several ingredients that have been recognized in the
literature as pro-cyclical triggers of financial distress in the banking
system: credit and liquidity shocks through bilateral exposures, liquidity
hoarding due to counterparty creditworthiness deterioration, target leveraging
policies and fire-sales spillovers. But we exclude the possibility of central
authorities intervention. We implement this framework on a dataset of 183
European banks that were publicly traded between 2004 and 2013. We document the
extreme fragility of the interbank lending market up to 2008, when a systemic
crisis leads to total depletion of market equity with an increasing speed of
market collapse. After the crisis instead the system is more resilient to
systemic events in terms of residual market equity. However, the speed at which
the crisis breaks out reaches a new maximum in 2011, and never goes back to
values observed before 2007. Our analysis points to the key role of the crisis
outbreak speed, which sets the maximum delay for central authorities
intervention to be effective.


title:
Diffusion of Hydrogen in Proton Implanted Silicon: Dependence on the
  Hydrogen Concentration

abstract:
  The reported diffusion constants for hydrogen in silicon vary over six orders
of magnitude. This spread in measured values is caused by the different
concentrations of defects in the silicon that has been studied. Hydrogen
diffusion is slowed down as it interacts with impurities. By changing the
material properties such as the crystallinity, doping type and impurity
concentrations, the diffusivity of hydrogen can be changed by several orders of
magnitude. In this study the influence of the hydrogen concentration on the
temperature dependence of the diffusion in high energy proton implanted silicon
is investigated. We show that the Arrhenius parameters, which describe this
temperature dependence decrease with increasing hydrogen concentration. We
propose a model where the relevant defects that mediate hydrogen diffusion
become saturated with hydrogen at high concentrations. When the defects that
provide hydrogen with the lowest energy positions in the lattice are saturated,
hydrogen resides at energetically less favorable positions and this increases
the diffusion of hydrogen through the crystal. Furthermore, we present a survey
of different studies on the diffusion of hydrogen. We observed a correlation of
the Arrhenius parameters calculated in those studies, leading to a modification
of the Arrhenius equation for the diffusion of hydrogen in silicon.

categories: cond-mat.mtrl-sci physics.acc-ph physics.chem-ph physics.ins-det


title: An Analysis of the New LHC Data through the Dispersion Relations

abstract:
  We analyse the tension between the (indirect) measurements of the total cross
section, and show the impact of various assumptions on the extraction of the
parameters from the elastic scattering amplitude, with a special attention to
the total cross section. In particular, the determination of the phase of the
elastic scattering amplitude will play an important role, and we shall study it
via dispersion relations. We shall also examine the origin of the dependence on
momentum transfer of the slopes of the different parts of the scattering
amplitude in different models. We shall also give the results of another
similar analysis based on a Regge-trajectory approach for the hadron scattering
amplitude.


title:
Explicit Polynomials Having the Higman-Sims Group as Galois Group over
  Q(t)

abstract:
  We compute explicit polynomials having the sporadic Higman-Sims group HS and
its automorphism group Aut(HS) as Galois groups over the rational function
field Q(t).


title:
Coherence time of over a second in a telecom-compatible quantum memory
  storage material

abstract:
  Quantum memories for light will be essential elements in future long-range
quantum communication networks. These memories operate by reversibly mapping
the quantum state of light onto the quantum transitions of a material system.
For networks, the quantum coherence times of these transitions must be long
compared to the network transmission times, approximately 100 ms for a global
communication network. Due to a lack of a suitable storage material, a quantum
memory that operates in the 1550 nm optical fiber communication band with a
storage time greater than 1 us has not been demonstrated. Here we describe the
spin dynamics of $^{167}$Er$^{3+}:$Y$_{2}$SiO$_{5}$ in a high magnetic field
and demonstrate that this material has the characteristics for a practical
quantum memory in the 1550 nm communication band. We observe a hyperfine
coherence time of 1.3 seconds. Further, we demonstrate efficient optical
pumping of the entire ensemble into a single hyperfine state, the first such
demonstration in a rare-earth system and a requirement for broadband spin-wave
storage. With an absorption of 70 dB/cm at 1538 nm and $\Lambda$-transitions
enabling spin-wave storage, this material is the first candidate identified for
an efficient, broadband quantum memory at telecommunication wavelengths.


title:
Data Mining for Three-Dimensional Organic Dirac Materials: Focus on
  Space Group 19

abstract:
  We combined the group theory and data mining approach within the Organic
Materials Database that leads to the prediction of stable Dirac-point nodes
within the electronic band structure of 3-dimensional organic crystals. We find
a particular space group $P2_12_12_1$ ($\#19$) that is conducive to the Dirac
nodes formation. We prove that nodes are a consequence of the orthorhombic
crystal structure. Within the electronic band structure, two different kinds of
nodes can be distinguished: 8-fold degenerate Dirac nodes protected by the
crystalline symmetry and 4-fold degenerate Dirac nodes protected by band
topology. Mining the Organic Materials Database, we present band structure
calculations and symmetry analysis for 6 previously synthesized organic
materials. In all these materials, the Dirac nodes are well separated within
the energy and located near the Fermi surface, which opens up a possibility for
their direct experimental observation.


title:
Towards an explicit local Jacquet-Langlands correspondence beyond the
  cuspidal case

abstract:
  We show how the modular representation theory of inner forms of general
linear groups over a non-Archimedean local field can be brought to bear on the
complex theory in a remarkable way. Let F be a non-Archimedean locally compact
field of residue characteristic p, and let G be an inner form of the general
linear group GL(n,F). We consider the problem of describing explicitly the
local Jacquet--Langlands correspondence between the complex discrete series
representations of G and GL(n,F), in terms of type theory. We show that the
congruence properties of the local Jacquet--Langlands correspondence exhibited
by A. M\'inguez and the first named author give information about the explicit
description of this correspondence. We prove that the problem of the invariance
of the endo-class by the Jacquet--Langlands correspondence can be reduced to
the case where the representations $\pi$ and its Jacquet--Langlands transfer
JL($\pi$) are both cuspidal with torsion number 1. We also give an explicit
description of the Jacquet--Langlands correspondence for all essentially tame
discrete series representations of G, up to an unramified twist, in terms of
admissible pairs, generalizing previous results by Bushnell and Henniart. In
positive depth, our results are the first beyond the case where $\pi$ and
JL($\pi$) are both cuspidal.


title:
Venus cloud morphology and motions from ground-based images at the time
  of the Akatsuki orbit insertion

abstract:
  We report Venus image observations around the two maximum elongations of the
planet at June and October 2015. From these images we describe the global
atmospheric dynamics and cloud morphology in the planet before the arrival of
JAXA Akatsuki mission on December the 7th. The majority of the images were
acquired at ultraviolet wavelengths (380-410 nm) using small telescopes. The
Venus dayside was also observed with narrow band filters at other wavelengths
(890 nm, 725-950 nm, 1.435 {\mu}m CO2 band) using the instrument
PlanetCam-UPV/EHU at the 2.2m telescope in Calar Alto Observatory. In all
cases, the lucky imaging methodology was used to improve the spatial resolution
of the images over the atmospheric seeing. During the April-June period, the
morphology of the upper cloud showed an irregular and chaotic texture with a
well developed equatorial dark belt (afternoon hemisphere), whereas during
October-December the dynamical regime was dominated by planetary-scale waves
(Yhorizontal, C-reversed and {\psi}-horizontal features) formed by long
streaks, and banding suggesting more stable conditions. Measurements of the
zonal wind velocity with cloud tracking in the latitude range from
50$^{\circ}$N to 50$^{\circ}$S shows agreement with retrievals from previous
works.


title: Type one generalized Calabi--Yaus

abstract:
  We study type one generalized complex and generalized Calabi--Yau manifolds.
We introduce a cohomology class that obstructs the existence of a globally
defined, closed 2-form which agrees with the symplectic form on the leaves of
the generalized complex structure, the twisting class. We prove that in a
compact, type one, 4n-dimensional generalized complex manifold the Euler
characteristic must be even and equal to the signature modulo four. The
generalized Calabi--Yau condition places much stronger constrains: a compact
type one generalized Calabi--Yau fibers over the 2-torus and if the structure
has one compact leaf, then this fibration can be chosen to be the fibration by
the symplectic leaves of the generalized complex structure. If the twisting
class vanishes, one can always deform the structure so that it has a compact
leaf. Finally we prove that every symplectic fibration over the 2-torus admits
a type one generalized Calabi--Yau structure.


title:
Regularization and analytic option pricing under $\alpha$-stable
  distribution of arbitrary asymmetry

abstract:
  We consider a non-Gaussian option pricing model, into which the underlying
log-price is assumed to be driven by an $\alpha$-stable distribution. We remove
the a priori divergence of the model by introducing a Mellin regularization for
the L\'evy propagator. Using distributional and $\mathbb{C}^n$ tools, we derive
an analytic closed formula for the option price, valid for any stability
$\alpha\in]1,2]$ and any asymmetry. This formula is very efficient and recovers
previous cases (Black-Scholes, Carr-Wu); we calibrate the formula on market
datas, make numerical tests, and discuss its many interesting properties.


title:
Interpolation inequalities, nonlinear flows, boundary terms, optimality
  and linearization

abstract:
  This paper is devoted to the computation of the asymptotic boundary terms in
entropy methods applied to a fast diffusion equation with weights associated
with Caffarelli-Kohn-Nirenberg interpolation inequalities. So far, only
elliptic equations have been considered and our goal is to justify, at least
partially, an extension of the carr{\'e} du champ / Bakry-Emery / R{\'e}nyi
entropy methods to parabolic equations. This makes sense because evolution
equations are at the core of the heuristics of the method even when only
elliptic equations are considered, but this also raises difficult questions on
the regularity and on the growth of the solutions in presence of weights.We
also investigate the relations between the optimal constant in the entropy -
entropy production inequality, the optimal constant in the information -
information production inequality, the asymptotic growth rate of generalized
R{\'e}nyi entropy powers under the action of the evolution equation and the
optimal range of parameters for symmetry breaking issues in
Caffarelli-Kohn-Nirenberg inequalities, under the assumption that the weights
do not introduce singular boundary terms at x=0. These considerations are new
even in the case without weights. For instance, we establish the equivalence of
carr{\'e} du champ and R{\'e}nyi entropy methods and explain why entropy
methods produce optimal constants in entropy - entropy production and
Gagliardo-Nirenberg inequalities in absence of weights, or optimal symmetry
ranges when weights are present.


title:
Flavor structure, Higgs boson mass and dark matter in supersymmetric
  model with vector-like generations

abstract:
  We study a supersymmetric model in which the Higgs mass, the muon anomalous
magnetic moment and the dark matter are simultaneously explained with extra
vector-like generation multiplets. For the explanations, non-trivial flavor
structures and a singlet field are required. In this paper, we study the flavor
texture by using the Froggatt-Nielsen mechanism, and then find realistic flavor
structures which reproduce the Cabbibo-Kobayashi-Maskawa matrix and fermion
masses at low energy. Furthermore, we find that the fermion component of the
singlet field becomes a good candidate of dark matter. In our model, flavor
physics and dark matter are explained with moderate size couplings through
renormalization group flows, and the presence of dark matter supports the
existence of just three generations in low energy scales. We analyze the
parameter region where the current thermal relic abundance of dark matter, the
Higgs boson mass and the muon $g-2$ can be explained simultaneously.


title:
Central limit theorem and bootstrap procedure for Wasserstein's
  variations with an application to structural relationships between
  distributions

abstract:
  Wasserstein barycenters and variance-like criteria based on the Wasserstein
distance are used in many problems to analyze the homogeneity of collections of
distributions and structural relationships between the observations. We propose
the estimation of the quantiles of the empirical process of Wasserstein's
variation using a bootstrap procedure. We then use these results for
statistical inference on a distribution registration model for general
deformation functions. The tests are based on the variance of the distributions
with respect to their Wasserstein's barycenters for which we prove central
limit theorems, including bootstrap versions.


abstract:
  We give an overview of new and existing cut- and flow-based ILP formulations
for the two-stage stochastic Steiner tree problem and compare the strength of
the LP relaxations.


title: Two-step homogeneous geodesics in homogeneous spaces

abstract:
  We study geodesics of the form $\gamma(t)=\pi(\exp(tX)\exp(tY))$, $X,Y\in
\fr{g}=\operatorname{Lie}(G)$, in homogeneous spaces $G/K$, where
$\pi:G\rightarrow G/K$ is the natural projection. These curves naturally
generalise homogeneous geodesics, that is orbits of one-parameter subgroups of
$G$ (i.e. $\gamma(t)=\pi(\exp (tX))$, $X\in \fr{g}$). We obtain sufficient
conditions on a homogeneous space implying the existence of such geodesics for
$X,Y\in \fr{m}=T_o(G/K)$. We use these conditions to obtain examples of
Riemannian homogeneous spaces $G/K$ so that all geodesics of $G/K$ are of the
above form. These include total spaces of homogeneous Riemannian submersions
endowed with one parameter families of fiber bundle metrics, Lie groups endowed
with special one parameter families of left-invariant metrics, generalised
Wallach spaces, generalized flag manifolds, and $k$-symmetric spaces with
$k$-even, equipped with certain one-parameter families of invariant metrics.


title:
`Who would have thought of that!': A Hierarchical Topic Model for
  Extraction of Sarcasm-prevalent Topics and Sarcasm Detection

abstract:
  Topic Models have been reported to be beneficial for aspect-based sentiment
analysis. This paper reports a simple topic model for sarcasm detection, a
first, to the best of our knowledge. Designed on the basis of the intuition
that sarcastic tweets are likely to have a mixture of words of both sentiments
as against tweets with literal sentiment (either positive or negative), our
hierarchical topic model discovers sarcasm-prevalent topics and topic-level
sentiment. Using a dataset of tweets labeled using hashtags, the model
estimates topic-level, and sentiment-level distributions. Our evaluation shows
that topics such as `work', `gun laws', `weather' are sarcasm-prevalent topics.
Our model is also able to discover the mixture of sentiment-bearing words that
exist in a text of a given sentiment-related label. Finally, we apply our model
to predict sarcasm in tweets. We outperform two prior work based on statistical
classifiers with specific features, by around 25\%.


title: On ideal dynamic climbing ropes

abstract:
  We consider the rope climber fall problem in two different settings. The
simplest formulation of the problem is when the climber falls from a given
altitude and is attached to one end of the rope while the other end of the rope
is attached to the rock at a given height. The problem is then finding the
properties of the rope for which the peak force felt by the climber during the
fall is minimal. The second problem of our consideration is again minimizing
the same quantity in the presence of a carabiner. We will call such ropes
\textit{mathematically ideal.} Given the height of the carabiner, the initial
height and the mass of the climber, the length of the unstretched rope, and the
distance between the belayer and the carabineer, we find the optimal (in the
sense of minimized the peak force to a given elongation) dynamic rope in the
framework of nonlinear elasticity. Wires of shape memory materials have some of
the desired features of the tension-strain relation of a mathematically ideal
dynamic rope, namely a plateau in the tension over a range of strains. With a
suitable hysteresis loop, they also absorb essentially all the energy from the
fall, thus making them an ideal rope in this sense too.


title: Polarization-entangled twin photons from two-photon quantum-dot emission

abstract:
  Semiconductor quantum dots are promising sources for polarization-entangled
photons. As an alternative to the usual cascaded biexciton-exciton emission,
direct two-photon emission from the biexciton can be used. With a high-quality
optical resonator tuned to half the biexciton energy, a large proportion of the
photons can be steered into the two-photon emission channel. In this case the
degree of polarization entanglement is inherently insensitive to the exciton
fine-structure splitting. In the present work we analyze the biexciton emission
with particular emphasis on the influence of coupling of the quantum-dot cavity
system to its environment. Especially for a high-quality cavity, the coupling
to the surrounding semiconductor material can open up additional
phonon-assisted decay channels. Our analysis demonstrates that with the cavity
tuned to half the biexciton energy, the potentially detrimental influence of
the phonons on the polarization entanglement is strongly suppressed -- high
degrees of entanglement can still be achieved. We further discuss spectral
properties and statistics of the emitted twin photons.


title:
Probing seismic solar analogues through observations with the NASA
  Kepler space telescope and HERMES high-resolution spectrograph

abstract:
  Stars similar to the Sun, known as solar analogues, provide an excellent
opportunity to study the preceding and following evolutionary phases of our
host star. The unprecedented quality of photometric data collected by the
\Kepler NASA mission allows us to characterise solar-like stars through
asteroseismology and study diagnostics of stellar evolution, such as variation
of magnetic activity, rotation and the surface lithium abundance. In this
project, presented in a series of papers by Salabert et al. (2016a,b) and Beck
et al (2016a,b), we investigate the link between stellar activity, rotation,
lithium abundance and oscillations in a group of 18 solar-analogue stars
through space photometry, obtained with the NASA Kepler space telescope and
from currently 50+ hours of ground-based, high-resolution spectroscopy with the
Hermes instrument. In these proceedings, we first discuss the selection of the
stars in the sample, observations and calibrations and then summarise the main
results of the project. By investigating the chromospheric and photospheric
activity of the solar analogues in this sample, it was shown that for a large
fraction of these stars the measured activity levels are compatible to levels
of the 11-year solar activity cycle 23. A clear correlation between the lithium
abundance and surface rotation was found for rotation periods shorter than the
solar value. Comparing the lithium abundance measured in the solar analogues to
evolutionary models with the Toulouse-Geneva Evolutionary Code (TGEC), we found
that the solar models calibrated to the Sun also correctly describe the set of
solar/stellar analogs showing that they share the same internal mixing physics.
Finally, the star KIC 3241581 and KIC 10644353 are discussed in more detail.


title:
Adaptive Experimental Design for Path-following Performance Assessment
  of Unmanned Vehicles

abstract:
  The definition of Good Experimental Methodologies (GEMs) in robotics is a
topic of widespread interest due also to the increasing employment of robots in
everyday civilian life. The present work contributes to the ongoing discussion
on GEMs for Unmanned Surface Vehicles (USVs). It focuses on the definition of
GEMs and provides specific guidelines for path-following experiments.
Statistically designed experiments (DoE) offer a valid basis for developing an
empirical model of the system being investigated. A two-step adaptive
experimental procedure for evaluating path-following performance and based on
DoE, is tested on the simulator of the Charlie USV. The paper argues the
necessity of performing extensive simulations prior to the execution of field
trials.


title: Electrodynamics of pulsar magnetospheres

abstract:
  We review electrodynamics of rotating magnetized neutron stars, from the
early vacuum model to recent numerical experiments with plasma-filled
magnetospheres. Significant progress became possible due to the development of
global particle-in-cell simulations which capture particle acceleration,
emission of high-energy photons, and electron-positron pair creation. The
numerical experiments show from first principles how and where electric gaps
form, and promise to explain the observed pulsar activity from radio waves to
gamma-rays.


title: On the description of exotic hadron states within QCD sum rules

abstract:
  Revisiting the QCD sum-rule description of exotic hadron states, we argue
that, in order to arrive at trustable analyses of, for instance, strong decay
widths of multiquarks, it is inevitable to adopt the QCD sum-rule approach
beyond the leading perturbative level.


title: Fisher Information Framework for Time Series Modeling

abstract:
  A robust prediction model invoking the Takens embedding theorem, whose
\textit{working hypothesis} is obtained via an inference procedure based on the
minimum Fisher information principle, is presented. The coefficients of the
ansatz, central to the \textit{working hypothesis} satisfy a time independent
Schr\"{o}dinger-like equation in a vector setting. The inference of i) the
probability density function of the coefficients of the \textit{working
hypothesis} and ii) the establishing of constraint driven pseudo-inverse
condition for the modeling phase of the prediction scheme, is made, for the
case of normal distributions, with the aid of the quantum mechanical virial
theorem. The well-known reciprocity relations and the associated Legendre
transform structure for the Fisher information measure (FIM, hereafter)-based
model in a vector setting (with least square constraints) are self-consistently
derived. These relations are demonstrated to yield an intriguing form of the
FIM for the modeling phase, which defines the \textit{working hypothesis},
solely in terms of the observed data. Cases for prediction employing time
series' obtained from the: $(i)$ the Mackey-Glass delay-differential equation,
$(ii)$ one ECG sample from the MIT-Beth Israel Deaconess Hospital (MIT-BIH)
cardiac arrhythmia database, and $(iii)$ one ECG from the Creighton University
ventricular tachyarrhythmia database. The ECG samples were obtained from the
Physionet online repository. These examples demonstrate the efficiency of the
prediction model. Numerical examples for exemplary cases are provided.

categories: stat.ME cs.IT math.IT nlin.CD physics.data-an


title: Charming quasi-exotic open-flavor mesons

abstract:
  We discuss charmed mesons in the covariant
Dyson-Schwinger-Bethe-Salpeter-equation approach. In particular we computed
masses, leptonic decay constants, and an orbital-angular-momentum decomposition
for a basic set of states. We also report an efficient way to treat the two
coupled quark propagator dressing functions via a single function.


title: Optical phonons for Peierls chains with long-range Coulomb interactions

abstract:
  We consider a chain of atoms that are bound together by a harmonic force.
Spin-1/2 electrons that move between neighboring chain sites (H\"uckel model)
induce a lattice dimerization at half band filling (Peierls effect). We
supplement the H\"uckel model with a local Hubbard interaction and a long-range
Ohno potential, and calculate the average bond-length, dimerization, and
optical phonon frequencies for finite straight and zig-zag chains using the
density-matrix renormalization group (DMRG) method. We check our numerical
approach against analytic results for the H\"uckel model. The Hubbard
interaction mildly affects the average bond length but substantially enhances
the dimerization and increases the optical phonon frequencies whereas, for
moderate Coulomb parameters, the long-range Ohno interaction plays no role.


title: Einstein-Rosen "Bridge" Revisited and Lightlike Thin-Shell Wormholes

abstract:
  We study in some detail the properties of the mathematically correct
formulation of the classical Einstein-Rosen "bridge" as proposed in the
original 1935 paper, which was shown in a series of previous papers of ours to
represent the simplest example of a static spherically symmetric traversable
lightlike thin-shell wormhole. Thus, the original Einstein-Rosen "bridge" is
not equivalent to the concept of the dynamical and non-traversable
Schwarzschild wormhole, also called "Einstein-Rosen bridge" in modern textbooks
on general relativity. The original Einstein-Rosen "bridge" requires the
presence of a special kind of "exotic" matter source located on its throat
which was shown to be the simplest member of the previously introduced by us
class of lightlike membranes. We introduce and exploit the Kruskal-Penrose
description of the original Einstein-Rosen "bridge". In particular, we
explicitly construct closed timelike geodesics on the pertinent Kruskal-Penrose
manifold.


title: Quantization of Yang-Mills Theories without the Gribov Ambiguity

abstract:
  A gauge condition is presented here to quantize non-Abelian gauge theory on
the manifold $R\otimes S^{1}\otimes S^{1}\otimes S^{1}$, which is free from the
Gribov ambiguity. Perturbative calculations in the new gauge behave like the
axial gauge in ultraviolet region, while infrared behaviours of the
perturbative series are quite nontrivial. The new gauge condition, which reads
$n\cdot\partial n\cdot A=0$, may not satisfy the requirement that
$A^{\mu}(\infty)=0$ in conventional perturbative calculations. However, such
contradiction is not harmful for gauge theories constructed on the manifold
$R\otimes S^{1}\otimes S^{1}\otimes S^{1}$.


title:
$B\to K^*\ell^+\ell^-$ in the Standard Model: Elaborations and
  Interpretations

abstract:
  Disentangling New Physics effects from the Standard Model requires a good
understanding of all pieces that stem from the latter, especially the
uncertainties that might plague the theoretical estimations within the Standard
Model. In the light of recent measurements made in the decay of $B\to
K^*\ell^+\ell^-$, and accompanying possibilities of New Physics effects, we
re-examine the hadronic uncertainties that come about in this exclusive $b \to
s$ transition. We show that it is not trivial to distinguish New Physics
effects from these hadronic uncertainties and we attempt to quantify the latter
in its magnitude and kinematic shape from the recent LHCb measurements of the
angular observables in this decay mode. We also update our fit with the more
recent calculations of the form factors combined with the ones computed with
Lattice QCD.


title:
Influence of $\mathcal{PT}$-symmetric complex potentials on the
  decoupling mechanism in quantum transport process

abstract:
  We consider one system in which the terminal dots of a one-dimensional
quantum-dot chain couple equally to the left and right leads and study the
influence of $\mathcal{PT}$-symmetric complex potentials on the quantum
transport process. It is found that in the case of the Hermitian Hamiltonian,
remarkable decoupling and antiresonance phenomena have an opportunity to
co-occur in the transport process. For the chains with odd(even) dots, all
their even(odd)-numbered molecular states decouple from the leads. Meanwhile,
antiresonance occurs at the positions of the even(odd)-numbered eigenenergies
of the sub-chains without terminal dots. When the $\mathcal{PT}$-symmetric
complex potentials are introduced to the terminal dots, the decoupling
phenomenon is found to transform into the Fano antiresonance. In addition, it
shows that appropriate magnetic flux can interchange the roles of the odd and
even molecular states. These results can assist to understand the quantum
transport modified by the $\mathcal{PT}$ symmetry in non-Hermitian discrete
systems.


title:
A large sample of Kohonen selected E+A (post-starburst) galaxies from
  the Sloan Digital Sky Survey

abstract:
  We aim to create a large sample of local post-starburst (PSB) galaxies to
study their characteristic properties, particularly morphological features
indicative of gravitational distortions and indications for active galactic
nuclei (AGNs). The selection is based on a huge Kohonen self-organising map
(SOM) of about one million SDSS spectra. The SOM is made fully available for
the astronomical community, in combination with an interactive user interface.
We compiled a catalogue of 2665 PSB galaxies with redshifts z < 0.4. In the
colour-mass diagram, the PSB sample is found to be clearly concentrated towards
the region between the red and the blue cloud, in agreement with the idea that
PSB galaxies represent the transitioning phase between actively and passively
evolving galaxies. The relative frequency of morphologically distorted PSB
galaxies is at least 57%, significantly higher than in a comparison sample. The
search for AGNs based on conventional selection criteria in the radio and MIR
results in a low AGN fraction of 2 - 3%. We confirm an MIR excess in the mean
SED of the PSB galaxy sample that may indicate hidden AGNs, though other
sources are also possible. (Abstract modified to match the arXiv format.)


title: Counting generalized Reed-Solomon codes

abstract:
  In this article we count the number of generalized Reed-Solomon (GRS) codes
of dimension k and length n, including the codes coming from a non-degenerate
conic plus nucleus. We compare our results with known formulae for the number
of 3-dimensional MDS codes of length n=6,7,8,9.


title: Shear Acceleration in Expanding Flows

abstract:
  Shear flows are naturally expected to occur in astrophysical environments and
potential sites of continuous non-thermal Fermi-type particle acceleration.
Here we investigate the efficiency of expanding relativistic outflows to
facilitate the acceleration of energetic charged particles to higher energies.
To this end, the gradual shear acceleration coefficient is derived based on an
analytical treatment. The results are applied to the context of the
relativistic jets of active galactic nuclei. The inferred acceleration
timescale is investigated for a variety of conical flow profiles (i.e., power
law, Gaussian, Fermi-Dirac) and compared to the relevant radiative and
non-radiative loss timescales. The results exemplify that relativistic shear
flows are capable of boosting cosmic-rays to extreme energies. Efficient
electron acceleration, on the other hand, requires weak magnetic fields and may
thus be accompanied by a delayed onset of particle energization and affect the
overall jet appearance (e.g., core, ridge line and limb-brightening).


title: Gravitational Lensing by Polytropic Wormholes

abstract:
  We obtain static multi-polytropic wormhole solutions in the framework of GR
gravity. The resulting metric is asymptotically Minkowskian, and locally that
of a wormhole. We also examine gravitational lensing by the wormhole, and
calculate the deflection angle for weak and strong field limits. We investigate
microlensing in the weak field limit and obtain corresponding light curves for
both galactic and extragalactic situations. We discuss the multi-polytropic
equation of state for the energy-momentum tensor which supports this geometry
and finally, we check for the satisfaction of the weak energy condition.


title:
Manifolds which admit maps with finitely many critical points into
  spheres of small dimensions

abstract:
  We construct, for $m\geq 6$ and $2n\leq m$, closed manifolds $M^{m}$ with
finite nonzero $\varphi(M^{m},S^{n}$), where $\varphi(M,N)$ denotes the minimum
number of critical points of a smooth map $M\to N$. We also give some explicit
families of examples for even $m\geq 6, n=3$, taking advantage of the Lie group
structure on $S^3$. Moreover, there are infinitely many such examples with
$\varphi(M^{m},S^{n})=1$. Eventually we compute the signature of the manifolds
$M^{2n}$ occurring for even $n$.


title:
VSPs of cubic fourfolds and the Gorenstein locus of the Hilbert scheme
  of 14 points on A^6

abstract:
  This paper is concerned with the geometry of the Gorenstein locus of the
Hilbert scheme of $14$ points on $\mathbb{A}^6$. This scheme has two
components: the smoothable one and an exceptional one. We prove that the latter
is smooth and identify the intersection of components as a vector bundle over
the Iliev-Ranestad divisor in the space of cubic fourfolds. The ninth secant
variety of the triple Veronese reembedding lies inside the Iliev-Ranestad
divisor. We point out that this secant variety is set-theoretically a
codimension two complete intersection and discuss the degrees of its equations.


title:
Current Sheet Structures Observed by the TESIS EUV Telescope During A
  Flux Rope Eruption on the Sun

abstract:
  We use the TESIS EUV telescope to study the current sheet signatures observed
during flux rope eruption. The special feature of the TESIS telescope was its
ability to image the solar corona up to a distance of 2 $R_\odot$ from the
Sun's center in the Fe 171 \AA\ line. The Fe 171 \AA\ line emission illuminates
the magnetic field lines, and the TESIS images reveal the coronal magnetic
structure at high altitudes. The analyzed CME had a core with a spiral-flux
rope-structure. The spiral shape indicates that the flux rope radius varied
along its length. The flux rope had a complex temperature structure: cold legs
(70 000 K, observed in He 304 \AA\ line) and a hotter core (0.7 MK, observed in
Fe 171 \AA\ line). Such structure contradicts the common assumption that the
CME core is a cold prominence. When the CME impulsively accelerated, a dark
double Y-structure appeared below the flux rope. The Y-structure timing,
location, and morphology agree with the previously performed MHD simulations of
the current sheet. We interpreted the Y-structure as a hot envelope of the
current sheet and hot reconnection outflows. The Y-structure had a thickness
6.0 Mm. Its length increased over time from 79 Mm to more than 411 Mm.


title: Tuning of heat and charge transport by Majorana fermions

abstract:
  We investigate theoretically thermal and electrical conductances for the
system consisting of a quantum dot (QD) connected both to a pair of Majorana
fermions residing the edges of a Kitaev wire and two metallic leads. We
demonstrate that both quantities reveal pronounced resonances, whose positions
can be controlled by tuning of an asymmetry of the couplings of the QD and a
pair of MFs. Similar behavior is revealed for the thermopower, Wiedemann-Franz
law and dimensionless thermoelectric figure of merit. The considered geometry
can thus be used as a tuner of heat and charge transport assisted by MFs.


title: Tracking chains revisited

abstract:
  The structure ${\cal C}_2:=(1^\infty,\le,\le_1,\le_2)$, introduced and first
analyzed in Carlson and Wilken 2012 (APAL), is shown to be elementary
recursive. Here, $1^\infty$ denotes the proof-theoretic ordinal of the fragment
$\Pi^1_1$-$\mathrm{CA}_0$ of second order number theory, or equivalently the
set theory $\mathrm{KPl}_0$, which axiomatizes limits of models of
Kripke-Platek set theory with infinity. The partial orderings $\le_1$ and
$\le_2$ denote the relations of $\Sigma_1$- and $\Sigma_2$-elementary
substructure, respectively. In a subsequent article we will show that the
structure ${\cal C}_2$ comprises the core of the structure ${\cal R}_2$ of pure
elementary patterns of resemblance of order $2$. In Carlson and Wilken 2012
(APAL) the stage has been set by showing that the least ordinal containing a
cover of each pure pattern of order $2$ is $1^\infty$. However, it is not
obvious from Carlson and Wilken 2012 (APAL) that ${\cal C}_2$ is an elementary
recursive structure. This is shown here through a considerable disentanglement
in the description of connectivity components of $\le_1$ and $\le_2$. The key
to and starting point of our analysis is the apparatus of ordinal arithmetic
developed in Wilken 2007 (APAL) and in Section 5 of Carlson and Wilken 2012
(JSL), which was enhanced in Carlson and Wilken 2012 (APAL) specifically for
the analysis of ${\cal C}_2$.


title:
Bounds and Constructions for $\overline{3}$-Strongly Separable Codes
  with Length $3$

abstract:
  As separable code (SC, IEEE Trans Inf Theory 57:4843-4851, 2011) and
frameproof code (FPC, IEEE Trans Inf Theory 44:1897-1905, 1998) do in
multimedia fingerprinting, strongly separable code (SSC, Des. Codes and
Cryptogr.79:303-318, 2016) can be also used to construct anti-collusion codes.
Furthermore, SSC is better than FPC and SC in the applications for multimedia
fingerprinting since SSC has lower tracing complexity than that of SC (the same
complexity as FPC) and weaker structure than that of FPC. In this paper, we
first derive several upper bounds on the number of codewords of
$\overline{t}$-SSC. Then we focus on $\overline{3}$-SSC with codeword length
$3$, and obtain the following two main results: (1) An equivalence between an
SSC and an SC. %Consequently a more tighter upper bound $(3q^2/4)$ and lower
bound $(q^{3/2})$ on the number of codewords are obtained; (2) An improved
lower bound $\Omega (q^{5/3}+q^{4/3}-q)$ on the size of a $q$-ary SSC when
$q=q_1^6$ for any prime power $q_1\equiv\ 1 \pmod 6$, better than the before
known bound $\lfloor\sqrt{q}\rfloor^{3}$, which is obtained by means of
difference matrix and the known result on the subset of $\mathbb{F}^{n}_q$
containing no three points on a line.


title:
First-principles study of structural stability, dynamical and mechanical
  properties of Li2FeSiO4 polymorphs

abstract:
  Li2FeSiO4 is an important alternative cathode for next generation Li-ion
batteries due to its high theoretical capacity (330 mA h/g). However, its
development has faced significant challenges arising from structural complexity
and poor ionic conductivity. In the present work, the relative stability,
electronic structure, thermodynamics, and mechanical properties of potential
cathode material Li2FeSiO4 and its polymorphs have been studied by
state-of-the-art density-functional calculations. Among the 11 structural
arrangements considered for the structural optimization calculations, the
experimentally known monoclinic P21 modification is found to be the ground
state structure. The application of pressure originates a sequence of phase
transitions according to P21 - Pmn21 - I222, and the estimated values of the
critical pressure are found to be 0.38 and 1.93 GPa. The electronic structures
reveal that all the considered polymorphs have a non-metallic character, with
band gap values varying between 3.0 and 3.2 eV. The energy differences between
different polymorphs are small, and most of these structures are dynamically
stable. On the other hand, the calculation of single crystal elastic constants
reveals that only few Li2FeSiO4 polymorphs are mechanically stable. At room
temperature, the diffusion coefficient calculations of Li2FeSiO4 in different
polymorphs reveal that Li-ion conductivity of this material is destitute.


title:
Adding a spin to Kerker's condition: arbitrary scattering direction
  tuning of nano-antennas with designed excitation

abstract:
  We describe a method to control the directional scattering of a high index
dielectric nanosphere, which utilizes the unique focusing properties of an
azimuthally polarized phase vortex and a radially polarized beam to
independently excite insde the nanosphere a spinning magnetic dipole and a
linearly polarized electric dipole mode normal to the magnetic dipole. We show
that by simply adjusting the phase and amplitude of the field on the exit pupil
of the optical system, the scattering of the nanosphere can be tuned to any
direction within a plane and the method works over a broad wavelength range.


title:
Geometry dependence of surface lattice resonances in plasmonic
  nanoparticle arrays

abstract:
  Plasmonic nanoarrays which support collective surface lattice resonances
(SLRs) have become an exciting frontier in plasmonics. Compared with the
localized surface plasmon resonance (LSPR) in individual particles, these
collective modes have appealing advantages such as angle-dependent dispersions
and much narrower linewidths. Here, we investigate systematically how the
geometry of the lattice affects the SLRs supported by metallic nanoparticles.
We present a general theoretical framework from which the various SLR modes of
a given geometry can be straightforwardly obtained by a simple comparison of
the diffractive order (DO) vectors and orientation of the nanoparticle dipole
given by the polarization of the incident field. Our experimental measurements
show that while square, hexagonal, rectangular, honeycomb and Lieb lattice
arrays have similar spectra near the $\Gamma$-point ($k=0$), they have
remarkably different SLR dispersions. Furthermore, their dispersions are highly
dependent on the polarization. Numerical simulations are performed to elucidate
the field profiles of the different modes. Our findings extend the diversity of
SLRs in plasmonic nanoparticle arrays, and the theoretical framework provides a
simple model for interpreting the SLRs features, and vice versa, for designing
the geometrical patterns.


title: Herding Generalizes Diverse M -Best Solutions

abstract:
  We show that the algorithm to extract diverse M -solutions from a Conditional
Random Field (called divMbest [1]) takes exactly the form of a Herding
procedure [2], i.e. a deterministic dynamical system that produces a sequence
of hypotheses that respect a set of observed moment constraints. This
generalization enables us to invoke properties of Herding that show that
divMbest enforces implausible constraints which may yield wrong assumptions for
some problem settings. Our experiments in semantic segmentation demonstrate
that seeing divMbest as an instance of Herding leads to better alternatives for
the implausible constraints of divMbest.


title:
Revisiting Quasi-Periodic modulation in $\gamma$-ray Blazar PKS 2155-304
  with Fermi Pass 8 data

abstract:
  We examine the gamma-ray quasi-periodic variability of PKS 2155-304 with the
latest publicly available \emph{Fermi}-LAT Pass 8 data which covers the years
from 2008 August to 2016 October. We produce the light curves in two ways,
i.e., the exposure-weighted aperture photometry and the maximum likelihood
optimization. The light curves are then analyzed by using Lomb-Scargle
Periodogram (LSP) and Weighted Wavelet Z-transform (WWZ); and the results
reveal a significant quasi-periodicity with a period of $1.74\pm0.13$ years and
a significance of $\sim$ 4.9 $\sigma$. The constraint of multifrequencies
quasi-periodic variabilities on blazar emission model is discussed.


title:
Search for potential precursors for Si-atomic layer deposition- a
  quantum chemical study

abstract:
  Thin film of silicon is an interesting material for many technological
applications in electronic industry and in energy harvesting technologies, but
requires a method for controlled growth of thin films. The purpose of this
study is to screen a wide variety of Si content precursors for Si ALD reactions
using state-of-the-art density-functional calculations. Among the studied 85 Si
content precursors we found that C7H12OSi(Methoxy-trivinyl-silane) and C7H9NSi
(Benzyliminosilane) show positive indications for ALD reactivity for Si
deposition. We believe that this finding will be helpful to develop low-cost,
high-energy efficiency thin-film solar cells for future scale up implementation
in photovoltaics.


title: Power Series Approximations to Fekete Polynomials

abstract:
  We study how well Fekete polynomials $$ F_p(X) = \sum_{n=0}^{p-1}
\left(\frac{n}{p}\right) X^n \in {\mathbb Z}[X] $$ with the coefficients given
by Legendre symbols modulo a prime $p$, can be approximated by power series
representing algebraic functions of a given degree. We also obtain some
explicit results describing polynomial recurrence relations which are satisfied
by the coefficients of such algebraic functions.


title:
Selfie Detection by Synergy-Constraint Based Convolutional Neural
  Network

abstract:
  Categorisation of huge amount of data on the multimedia platform is a crucial
task. In this work, we propose a novel approach to address the subtle problem
of selfie detection for image database segregation on the web, given rapid rise
in number of selfies clicked. A Convolutional Neural Network (CNN) is modeled
to learn a synergy feature in the common subspace of head and shoulder
orientation, derived from Local Binary Pattern (LBP) and Histogram of Oriented
Gradients (HOG) features respectively. This synergy was captured by projecting
the aforementioned features using Canonical Correlation Analysis (CCA). We show
that the resulting network's convolutional activations in the neighbourhood of
spatial keypoints captured by SIFT are discriminative for selfie-detection. In
general, proposed approach aids in capturing intricacies present in the image
data and has the potential for usage in other subtle image analysis scenarios
apart from just selfie detection. We investigate and analyse the performance of
popular CNN architectures (GoogleNet, AlexNet), used for other image
classification tasks, when subjected to the task of detecting the selfies on
the multimedia platform. The results of the proposed approach are compared with
these popular architectures on a dataset of ninety thousand images comprising
of roughly equal number of selfies and non-selfies. Experimental results on
this dataset shows the effectiveness of the proposed approach.


title:
Character-level Convolutional Network for Text Classification Applied to
  Chinese Corpus

abstract:
  This article provides an interesting exploration of character-level
convolutional neural network solving Chinese corpus text classification
problem. We constructed a large-scale Chinese language dataset, and the result
shows that character-level convolutional neural network works better on Chinese
corpus than its corresponding pinyin format dataset. This is the first time
that character-level convolutional neural network applied to text
classification problem.


title:
Gray Box Identification of State-Space Models Using Difference of Convex
  Programming

abstract:
  Gray-box identification is prevalent in modeling physical and networked
systems. However, due to the non-convex nature of the gray-box identification
problem, good initial parameter estimates are crucial for a successful
application. In this paper, a new identification method is proposed by
exploiting the low-rank and structured Hankel matrix of impulse response. This
identification problem is recasted into a difference-of-convex programming
problem, which is then solved by the sequential convex programming approach
with the associated initialization obtained by nuclear-norm optimization. The
presented method aims to achieve the maximum impulse-response fitting while not
requiring additional (non-convex) conditions to secure non-singularity of the
similarity transformation relating the given state-space matrices to the
gray-box parameterized ones. This overcomes a persistent shortcoming in a
number of recent contributions on this topic, and the new method can be applied
for the structured state-space realization even if the involved system
parameters are unidentifiable. The method can be used both for directly
estimating the gray-box parameters and for providing initial parameter
estimates for further iterative search in a conventional gray-box
identification setup.


title: Limits of the time-multiplexed photon-counting method

abstract:
  The progress in building large quantum states and networks requires
sophisticated detection techniques to verify the desired operation. To achieve
this aim, a cost- and resource-efficient detection method is the time
multiplexing of photonic states. This design is assumed to be efficiently
scalable; however, it is restricted by inevitable losses and limited detection
efficiencies. Here, we investigate the scalability of time-multiplexed
detectors under the effects of fiber dispersion and losses. We use the
distinguishability of Fock states up to $n=20$ after passing the
time-multiplexed detector as our figure of merit and find that, for realistic
setup efficiencies of $\eta=0.85$, the optimal size for time-multiplexed
detectors is 256 bins.


title: Attending to Characters in Neural Sequence Labeling Models

abstract:
  Sequence labeling architectures use word embeddings for capturing similarity,
but suffer when handling previously unseen or rare words. We investigate
character-level extensions to such models and propose a novel architecture for
combining alternative word representations. By using an attention mechanism,
the model is able to dynamically decide how much information to use from a
word- or character-level component. We evaluated different architectures on a
range of sequence labeling datasets, and character-level extensions were found
to improve performance on every benchmark. In addition, the proposed
attention-based architecture delivered the best results even with a smaller
number of trainable parameters.


title:
Extension of the G{\"u}nter derivatives to Lipschitz domains and
  application to the boundary potentials of elastic waves

abstract:
  The scalar G{\"u}nter derivatives of a function defined on the boundary of a
three-dimensional domain are expressed as components (or their opposites) of
the tangential vector rotational of this function in the canonical orthonormal
basis of the ambient space. This in particular implies that these derivatives
define bounded operators from H s into H s--1 for 0 $\le$ s $\le$ 1 on the
boundary of a Lipschitz domain, and can easily be implemented in boundary
element codes. Regularization techniques for the trace and the traction of
elastic waves potentials, previously built for a domain of class C 2 , can thus
be extended to the Lipschitz case. In particular, this yields an elementary way
to establish the mapping properties of elastic wave potentials from those of
the Helmholtz equation without resorting to the more advanced theory for
elliptic systems. Some attention is finally paid to the two-dimensional case.


title: Weakly Learning to Match Experts in Online Community

abstract:
  In online question-and-answer (QA) websites like Quora, one central issue is
to find (invite) users who are able to provide answers to a given question and
at the same time would be unlikely to say "no" to the invitation. The challenge
is how to trade off the matching degree between users' expertise and the
question topic, and the likelihood of positive response from the invited users.
In this paper, we formally formulate the problem and develop a weakly
supervised factor graph (WeakFG) model to address the problem. The model
explicitly captures expertise matching degree between questions and users. To
model the likelihood that an invited user is willing to answer a specific
question, we incorporate a set of correlations based on social identity theory
into the WeakFG model. We use two different genres of datasets: QA-Expert and
Paper-Reviewer, to validate the proposed model. Our experimental results show
that the proposed model can significantly outperform (+1.5-10.7% by MAP) the
state-of-the-art algorithms for matching users (experts) with community
questions. We have also developed an online system to further demonstrate the
advantages of the proposed method.


title:
Testing the Odds of Inherent versus Observed Over-dispersion in Neural
  Spike Counts Odds of Inherent versus Observed Over-dispersion

abstract:
  The repeated presentation of an identical visual stimulus in the receptive
field of a neuron may evoke different spiking patterns at each trial.
Probabilistic methods are essential to understand the functional role of this
variance within the neural activity. In that case, a Poisson process is the
most common model of trial-to-trial variability. For a Poisson process, the
variance of the spike count is constrained to be equal to the mean,
irrespective of the duration of measurements. Numerous studies have shown that
this relationship does not generally hold. Specifically, a majority of
electrophysiological recordings show an " over-dispersion " effect: Responses
that exhibit more inter-trial variability than expected from a Poisson process
alone. A model that is particularly well suited to quantify over-dispersion is
the Negative-Binomial distribution model. This model is well-studied and widely
used but has only recently been applied to neuroscience. In this paper, we
address three main issues. First, we describe how the Negative-Binomial
distribution provides a model apt to account for overdispersed spike counts.
Second, we quantify the significance of this model for any neurophysiological
data by proposing a statistical test, which quantifies the odds that
over-dispersion could be due to the limited number of repetitions (trials). We
apply this test to three neurophysiological tests along the visual pathway.
Finally, we compare the performance of this model to the Poisson model on a
population decoding task. We show that the decoding accuracy is improved when
accounting for over-dispersion, especially under the hypothesis of tuned
over-dispersion.


title:
Maximum likelihood estimation of covariances of elliptically symmetric
  distributions

abstract:
  Elliptically symmetric distributions are widely used in portfolio modeling,
as well as in signal processing applications for modeling impulsive background
noises. Of particular interest are algorithms for covariance estimation and
subspace detection in such backgrounds.
  This article tackles the issue of correctly estimating the covariance matrix
associated to such models and detecting additional signal superimposed on such
distributions. A particular attention is given to the proper accounting of the
circular symmetry for the subclass of complex elliptical distributions in the
case of complex signals.
  In particular Tyler's estimator is shown to be a maximum likelihood estimate
over all elliptical models, and its extension to the complex case is shown to
be a maximum likelihood estimate for the subclass of complex elliptical models
(CES); other M-estimators are also shown to be maximum likelihood estimates
over some restricted classes of elliptical models. The extension of Tyler's and
other M-estimators to constrained covariance estimation is also discussed, in
particular for toeplitz constrains.
  Finally likelihood ratio signal detection tests associated to the various
estimators introduced in this article are also discussed.


title:
Evaluation of Decentralized Event-Triggered Control Strategies for
  Cyber-Physical Systems

abstract:
  Energy constraint long-range wireless sensor/ actuator based solutions are
theoretically the perfect choice to support the next generation of city-scale
cyber-physical systems. Traditional systems adopt periodic control which
increases network congestion and actuations while burdens the energy
consumption. Recent control theory studies overcome these problems by
introducing aperiodic strategies, such as event trigger control. In spite of
the potential savings, these strategies assume actuator continuous listening
while ignoring the sensing energy costs. In this paper, we fill this gap, by
enabling sensing and actuator listening duty-cycling and proposing two
innovative MAC protocols for three decentralized event trigger control
approaches. A laboratory experimental testbed, which emulates a smart water
network, was modelled and extended to evaluate the impact of system parameters
and the performance of each approach. Experimental results reveal the
predominance of the decentralized event-triggered control against the classic
periodic control either in terms of communication or actuation by promising
significant system lifetime extension.


title:
Off-equilibrium scaling driven by a time-dependent magnetic field in
  O(N) vector models

abstract:
  We investigate the off-equilibrium dynamics of a spin system with O($N$)
symmetry in $2 < d < 4$ spatial dimensions arising by the presence of a slowly
varying time-dependent magnetic field $h(t,t_s) \sim t/t_s$, $t_s$ is a time
scale, at the critical temperature $T = T_c$ and below it $T < T_c$. After
showing the general theory, we demonstrate the off-equilibrium scaling and we
formally compute the correlation functions in the limit of large $N$. We derive
the off-equilibrium scaling relations for the hysteresis loop area and for the
magnetic work done by the system when the magnetic field $h(t,t_s)$ is varied
across the phase transitions cyclically in time. We also investigate the first
deviations from the equilibrium behavior in the correlation functions checking
the consistence for an exponential approach.


title: A quantitative interpretation of the frequent hypercyclicity criterion

abstract:
  We give a quantitative interpretation of the Frequent Hypercyclicity
Criterion. Actually we show that an operator which satisfies the Frequent
Hypercyclicity Criterion is necessarily A-frequently hypercyclic, where A
refers to some weighted densities sharper than the natural lower density. In
that order, we exhibit different scales of weighted densities that are of
interest to quantify the "frequency" measured by the Frequent Hypercyclicity
Criterion. Moreover we construct an example of unilateral weighted shift which
is frequently hypercyclic but not A-frequently hypercyclic on a particular
scale.


title:
Feature Engineering and Ensemble Modeling for Paper Acceptance Rank
  Prediction

abstract:
  Measuring research impact and ranking academic achievement are important and
challenging problems. Having an objective picture of research institution is
particularly valuable for students, parents and funding agencies, and also
attracts attention from government and industry. KDD Cup 2016 proposes the
paper acceptance rank prediction task, in which the participants are asked to
rank the importance of institutions based on predicting how many of their
papers will be accepted at the 8 top conferences in computer science. In our
work, we adopt a three-step feature engineering method, including basic
features definition, finding similar conferences to enhance the feature set,
and dimension reduction using PCA. We propose three ranking models and the
ensemble methods for combining such models. Our experiment verifies the
effectiveness of our approach. In KDD Cup 2016, we achieved the overall rank of
the 2nd place.


title: Non-reconstructible locally finite graphs

abstract:
  Two graphs $G$ and $H$ are \emph{hypomorphic} if there exists a bijection
$\varphi \colon V(G) \rightarrow V(H)$ such that $G - v \cong H - \varphi(v)$
for each $v \in V(G)$. A graph $G$ is \emph{reconstructible} if $H \cong G$ for
all $H$ hypomorphic to $G$.
  Nash-Williams proved that all locally finite graphs with a finite number
$\geq 2$ of ends are reconstructible, and asked whether locally finite graphs
with one end or countably many ends are also reconstructible.
  In this paper we construct non-reconstructible graphs of bounded maximum
degree with one and countably many ends respectively, answering the two
questions of Nash-Williams about the reconstruction of locally finite graphs in
the negative.


title:
Shortcut to adiabatic control of soliton matter waves by tunable
  interaction

abstract:
  We propose a method for shortcut to adiabatic control of soliton matter waves
in harmonic traps. The tunable interaction controlled by Feshbach resonance is
inversely designed to achieve fast compression of soliton matter waves but
within a short time, as compared to the conventional adiabatic compression.
These results pave the way to control the nonlinear dynamics for matter waves
and optical solitons by using shortcuts to adiabaticity.


title: Hyperbolicity of direct products of graphs

abstract:
  If $X$ is a geodesic metric space and $x_1,x_2,x_3\in X$, a {\it geodesic
triangle} $T=\{x_1,x_2,x_3\}$ is the union of the three geodesics $[x_1x_2]$,
$[x_2x_3]$ and $[x_3x_1]$ in $X$. The space $X$ is $\delta$-\emph{hyperbolic}
$($in the Gromov sense$)$ if any side of $T$ is contained in a
$\delta$-neighborhood of the union of the two other sides, for every geodesic
triangle $T$ in $X$. If $X$ is hyperbolic, we denote by $\delta(X)$ the sharp
hyperbolicity constant of $X$, i.e., $\delta(X)=\inf\{\delta\ge 0: \, X \,
\text{ is $\delta$-hyperbolic}\,\}.$ Some previous works characterize the
hyperbolic product graphs (for the Cartesian, strong, join, corona and
lexicographic products) in terms of properties of the factor graphs. However,
the problem with the direct product is more complicated. In this paper, we
prove that if the direct product $G_1\times G_2$ is hyperbolic, then one factor
is hyperbolic and the other one is bounded. Also, we prove that this necessary
condition is, in fact, a characterization in many cases. In other cases, we
find characterizations which are not so simple. Furthermore, we obtain formulae
or good bounds for the hyperbolicity constant of the direct product of some
important graphs.


title: Derivatives of Feynman-Kac Semigroups

abstract:
  We prove Bismut-type formulae for the first and second derivatives of a
Feynman-Kac semigroup on a complete Riemannian manifold. We derive local
estimates and give bounds on the logarithmic derivatives of the integral
kernel. Stationary solutions are also considered. The arguments are based on
local martingales, although the assumptions are purely geometric.


title:
Nanoscale Chemical Evolution of Silicon Negative Electrodes
  Characterized by Low-Loss STEM-EELS

abstract:
  Continuous solid electrolyte interface (SEI) formation remains the limiting
factor of the lifetime of silicon nanoparticles (SiNPs) based negative
electrodes. Methods that could provide clear diagnosis of the electrode
degradation are of utmost necessity to streamline further developments. We
demonstrate that electron energy-loss spectroscopy (EELS) in a scanning
transmission electron microscope (STEM) can be used to quickly map SEI
components and quantify LixSi alloys from single experiments, with resolutions
down to 5 nm. Exploiting the low-loss part of the EEL spectrum allowed us to
circumvent the degradation phenomena that have so far crippled the application
of this technique on such beam-sensitive compounds. Our results provide
unprecedented insight into silicon aging mechanisms in full cell configuration.
We observe the morphology of the SEI to be extremely heterogeneous at the
particle scale but with clear chemical evolutions with extended cycling coming
from both SEI accumulation and a transition from lithium-rich carbonate-like
compounds to lithium-poor ones. Thanks to the retrieval of several results from
a single dataset, we were able to correlate local discrepancies in lithiation
to the initial crystallinity of silicon as well as to the local SEI chemistry
and morphology. This study emphasizes how initial heterogeneities in the
percolating electronic network and the porosity affect SiNPs aggregates along
cycling. These findings pinpoint the crucial role of an optimized formulation
in silicon-based thick electrodes.


title:
Shortcut to adiabatic population transfer in quantum three-level
  systems: effective two-level problems and feasible counter-diabatic driving

abstract:
  Shortcut to adiabaticity in various quantum systems has attracted much
attention with the wide applications in quantum information processing and
quantum control. In this paper, we concentrate on stimulated Raman
shortcut-to-adiabatic passage in quantum three-level systems. To implement
counter-diabatic driving but without additional coupling, we first reduce the
quantum three-level systems to effective two-level problems at large
intermediate-level detuning, or on resonance, apply counter-diabatic driving
along with the unitary transformation, and eventually modify the pump and
Stokes pulses for achieving fast and high-fidelity population transfer. The
required laser intensity and stability against parameter variation are further
discussed, to demonstrate the advantage of shortcuts to adiabaticity.


title:
A critical review of statistical calibration/prediction models handling
  data inconsistency and model inadequacy

abstract:
  Inference of physical parameters from reference data is a well studied
problem with many intricacies (inconsistent sets of data due to experimental
systematic errors, approximate physical models...). The complexity is further
increased when the inferred parameters are used to make predictions (virtual
measurements) because parameters uncertainty has to be estimated in addition to
parameters best value. The literature is rich in statistical models for the
calibration/prediction problem, each having benefits and limitations.
  We review and evaluate standard and state-of-the-art statistical models in a
common bayesian framework, and test them on synthetic and real datasets of
temperature-dependent viscosity for the calibration of Lennard-Jones parameters
of a Chapman-Enskog model.


title:
Origin of enhanced visible-light photocatalytic activity of transition
  metal (Fe, Cr and Co) doped CeO2: Effect of 3d-orbital splitting

abstract:
  Enhanced visible light photocatalytic activity of transition metal-doped
ceria (CeO2) nanomaterials have experimentally been demonstrated, whereas there
are very few reports mentioning the mechanism of this behavior. Here we use
first-principles calculations to explore the origin of enhanced photocatalytic
performance of CeO2 doped with transition metal impurities (Fe, Cr and Co).
When a transition metal atom substitutes a Ce atom into CeO2, t2g and eg levels
of 3d orbits appear in the middle of band gap owing to the effect of cubic
ligand field, and the former is higher than latter. Interestingly, t2g subset
of FeCe (CoCe and CrCe)-Vo-CeO2 is split into two parts: one merges into the
conduction band, the other as well as eg will remain in the gap, because O
vacancy defect adjacent to transition metal atom will break the symmetry of
cubic ligand field. These eg and t2g levels in the band gap are beneficial for
absorbing visible light and enhancing quantum efficiency because of forbidden
transition, which is one key factor for enhanced visible light photocatalytic
activity. The band gap narrowing also leads to a redshift of optical absorbance
and high photoactivity. These findings can rationalize the available
experimental results and provide some new insights for designing CeO2-based
photocatalysts with high photocatalytic performance.


title: Divergence of CAT(0) Cube Complexes and Coxeter Groups

abstract:
  We provide geometric conditions on a pair of hyperplanes of a CAT(0) cube
complex that imply divergence bounds for the cube complex. As an application,
we classify all right-angled Coxeter groups with quadratic divergence and show
right-angled Coxeter groups cannot exhibit a divergence function between
quadratic and cubic. This generalizes a theorem of Dani-Thomas that addressed
the class of 2-dimensional right-angled Coxeter groups. As another application,
we provide an inductive graph theoretic criteria on a right-angled Coxeter
group's defining graph which allows us to recognize arbitrary integer degree
polynomial divergence for many infinite classes of right-angled Coxeter groups.
We also provide similar divergence results for some classes of Coxeter groups
which are not right-angled.


title:
STM observation of a box-shaped graphene nanostructure appeared after
  mechanical cleavage of pyrolytic graphite

abstract:
  A description is given of a three-dimensional box-shaped graphene (BSG)
nanostructure formed/uncovered by mechanical cleavage of highly oriented
pyrolytic graphite (HOPG). The discovered nanostructure is a multilayer system
of parallel hollow channels located along the surface and having quadrangular
cross-section. The thickness of the channel walls/facets is approximately equal
to 1 nm. The typical width of channel facets makes about 25 nm, the channel
length is 390 nm and more. The investigation of the found nanostructure by
means of a scanning tunneling microscope (STM) allows us to draw a conclusion
that it is possible to make spatial constructions of graphene similar to the
discovered one by mechanical compression, bending, splitting, and shifting
graphite surface layers. The distinctive features of such constructions are the
following: simplicity of the preparation method, small contact area between
graphene planes and a substrate, large surface area, nanometer cross-sectional
sizes of the channels, large aspect ratio. Potential fields of application
include: ultra-sensitive detectors, high-performance catalytic cells,
nanochannels for DNA manipulation, nanomechanical resonators, electron
multiplication channels, high-capacity sorbents for hydrogen storage.


title:
QCD amplitudes with 2 initial spacelike legs via generalised BCFW
  recursion

abstract:
  We complete the generalisation of the BCFW recursion relation to the
off-shell case, allowing for the computation of tree level scattering
amplitudes for full High Energy Factorisation (HEF), i.e. with both incoming
partons having a non-vanishing transverse momentum. We provide explicit results
for color-ordered amplitudes with two off-shell legs in massless QCD up to 4
point, continuing the program begun in two previous papers. For the 4-fermion
amplitudes, which are not BCFW-recursible, we perform a diagrammatic
computation, so as to offer a complete set of expressions. We explicitly show
and discuss some plots of the squared $2 \rightarrow 2$ matrix elements as
functions of the differences in rapidity and azimuthal angle of the final state
particles.


title:
Recent progress on the understanding of the medium-induced jet evolution
  and energy loss in pQCD

abstract:
  Motivated by the striking modifications of jets observed both at RHIC and the
LHC, significant progress towards the understanding of jet dynamics within QGP
has occurred over the last few years. In this talk, I review the recent
theoretical developments in the study of medium-induced jet evolution and
energy loss within a perturbative framework. The main mechanisms of energy loss
and broadening will be firstly addressed with focus on leading particle
calculations beyond the eikonal approximation. Then, I will provide an overview
of the modifications of the interference pattern between the different parton
emitters that build up the parton shower when propagating through an extended
coloured medium. I will show that the interplay between color
coherence/decoherence that arises from such effects is the main mechanism for
the modification of the jet core angular structure. Finally, I discuss the
possibility of a probabilistic picture of the parton shower evolution in the
limit of a very dense or infinite medium.


title:
Measurement of the Absolute Branching Fraction for
  $\Lambda_c^+\rightarrow \Lambda \mu^+\nu_{\mu}$

abstract:
  We report the first measurement of the absolute branching fraction for
$\Lambda^+_{c}\rightarrow \Lambda \mu^+\nu_{\mu}$. This measurement is based on
a sample of $e^+e^-$ annihilation data at a center-of-mass energy of
$\sqrt{s}=4.6$ GeV collected with the BESIII detector at the BEPCII storage
rings. The sample corresponds to an integrated luminosity of 567 pb$^{-1}$. The
branching fraction is determined to be $\mathcal B({\Lambda^+_c\rightarrow
\Lambda \mu^+\nu_{\mu}})=(3.49\pm0.46({\rm stat})\pm0.27({\rm syst}))\%$. In
addition, we calculate the ratio $\mathcal{B}(\Lambda^+_c\rightarrow \Lambda
\mu^+\nu_{\mu})/\mathcal{B}(\Lambda^+_c\rightarrow \Lambda e^+\nu_{e})$ to be
$0.96\pm0.16({\rm stat})\pm0.04({\rm syst})$.


title: Relations between photoionization cross sections and photon radius

abstract:
  The relations between photoionization cross sections and photon radius are
obtained on basis of quantum mechanics and the particle-like properties of a
photon. The photoionization cross sections of H atom and H-like ions, He atom
and He like ions, alkali metal atoms, and Rydberg atoms are calculated using
the relations. The calculation results are found to be good agreement with the
known experimental data. The results show that the photoionization cross
section is always smaller than the cross section of the photon to ionize the
atom or ion and can be expressed as the product of the cross section of the
photon and the probability that electron meets with the photon. These provide
the intuitive understanding for the photoionization phenomena and open a new
avenue of research on interaction between a photon and an atom or ion.


title:
Dynamic Polarization and Relaxation of 75As Nuclei in Silicon at High
  Magnetic Field and Low Temperature

abstract:
  We present the results of experiments on dynamic nuclear polarization and
relaxation of 75As in silicon crystals. Experiments are performed in strong
magnetic fields of 4.6 T and temperatures below 1 K. At these conditions donor
electron spins are fully polarized, and the allowed and forbidden ESR
transitions are well resolved. We demonstrate effective nuclear polarization of
75As nuclei via the Overhauser effect on the time scale of several hundred
seconds. Excitation of the forbidden transitions leads to a polarization
through the solid effect. The relaxation rate of donor nuclei has strong
temperature dependence characteristic of Orbach process.


title: Dougall's $_5F_4$ sum and the WZ-algorithm

abstract:
  We show how to prove the examples of a paper by Chu and Zhang using the
WZ-algorithm.


title:
Electron-phonon scattering and in-plane electric conductivity in twisted
  bilayer graphene

abstract:
  We have surveyed the in-plane transport properties of the graphene twist
bilayer using (i) a low-energy effective Hamiltonian for the underlying
electronic structure, (ii) an isotropic elastic phonon model, and (iii) the
linear Boltzmann equation for elastic electron-phonon scattering. We find that
transport in the twist bilayer is profoundly sensitive to the rotation angle of
the constituent layers. Similar to the electronic structure of the twist
bilayer the transport is qualitatively different in three distinct angle
regimes. At large angles ($\theta > \,\approx\!\!10^\circ$) and at temperatures
below an interlayer Bloch-Gr\"uneisen temperature of $\approx 10$~K the
conductivity is independent of the twist angle i.e. the layers are fully
decoupled. Above this temperature the layers, even though decoupled in the
ground state, are re-coupled by electron-phonon scattering and the transport is
different both from single layer graphene as well as the Bernal bilayer. In the
small angle regime $\theta <\,\approx\!\!2^\circ$ the conductivity drops by two
orders of magnitude and develops a rich energy dependence, reflecting the
complexity of the underlying topological changes (Lifshitz transitions) of the
Fermi surface. At intermediate angles the conductivity decreases continuously
as the twist angle is reduced, while the energy dependence of the conductivity
presents two sharp transitions, that occur at specific angle dependent
energies, and that may be related to (i) the well studied van Hove singularity
of the twist bilayer and (ii) a Lifshitz transition that occurs when trigonally
placed electron pockets decorate the strongly warped Dirac cone. We examine the
role of a layer perpendicular electric field finding that it affects the
conductivity strongly at low temperatures whereas this effect is washed out by
Fermi smearing at room temperatures.


title:
Existence of dicritical singularities of Levi-flat hypersurfaces and
  holomorphic foliations

abstract:
  We study holomorphic foliations tangent to singular real-analytic Levi-flat
hypersurfaces in compact complex manifolds of complex dimension two. We give
some hypotheses to guarantee the existence of dicritical singularities of these
objects. As consequence, we give some applications to holomorphic foliations
tangent to real-analytic Levi-flat hypersurfaces with singularities in
$\mathbb{P}^2$.


title:
Probing quantum state space: does one have to learn everything to learn
  something?

abstract:
  Determining the state of a quantum system is a consuming procedure. For this
reason, whenever one is interested only in some particular property of a state,
it would be desirable to design a measurement setup that reveals this property
with as little effort as possible. Here we investigate whether, in order to
successfully complete a given task of this kind, one needs an informationally
complete measurement, or if something less demanding would suffice. The first
alternative means that in order to complete the task, one needs a measurement
which fully determines the state. We formulate the task as a membership problem
related to a partitioning of the quantum state space and, in doing so, connect
it to the geometry of the state space. For a general membership problem we
prove various sufficient criteria that force informational completeness, and we
explicitly treat several physically relevant examples. For the specific cases
that do not require informational completeness, we also determine bounds on the
minimal number of measurement outcomes needed to ensure success in the task.


title: Bratteli-Vershik models for partial actions of $\mathbb{Z}$

abstract:
  Let $U$ and $V$ be open subsets of the Cantor set with finite disjoint
complements, and let $h:U\to V$ be a homeomorphism with dense orbits. Building
from the ideas of Herman, Putnam, and Skau, we show that the partial action
induced by $h$ can be realized as the Vershik map on a Bratteli diagram, and
that any two such diagrams are equivalent.


title: Resonant subgap current transport in Josephson field effect transistor

abstract:
  We study theoretically the current-voltage characteristics (IVCs) of the
Josephson field effect transistor - a ballistic SNINS junction with
superconducting (S) electrodes confining a planar normal metal region (N),
which is controlled by the gate induced potential barrier (I). The calculations
were performed using the computation technique developed earlier for long
single-channel junctions in the coherent multiple Andreev reflections (MAR)
regime. We find significant difference of the subgap current structure in these
junctions compared to the subharmonic gap structure in tunnel junctions and
atomic-size point contacts. For long junctions, whose length significantly
exceeds the coherence length, the IVC exhibits current peaks at multiples
(harmonics) of the difference $\delta_m$ between the static Andreev levels,
$eV_n = n\delta_m$. Moreover, the averaged IVC follows the power rather than
exponential behavior, and has a universal scaling with the junction
transparency. This result is qualitatively understood using an analytical
approach based on the concept of resonant MAR trajectories. In shorter
junctions whose length is comparable to the coherence length, the IVC has an
exponential form common for point contacts, however the current structures
appear at the subharmonics of the Andreev interlevel distance, $eV_n =
\delta_m/n$ rather than the gap subharmonics $2\Delta/n$.


title:
The Kondo-lattice state in the presence of Van Hove singularities: a
  next-leading order scaling description

abstract:
  A renormalization group treatment of the Kondo model with logarithmic Van
Hove singularity in the electron density of states is performed within
next-leading order scaling, different magnetic phases being considered. The
effective coupling constant remains small, renormalized magnetic moment and
spin-fluctuation frequency decreasing by several orders of magnitude. Thus wide
non-Fermi-liquid behavior regions are found from the scaling trajectories in a
broad interval of the bare coupling parameter. Applications to itinerant
magnetism theory are discussed.


title: Discrete exterior calculus (DEC) for the surface Navier-Stokes equation

abstract:
  We consider a numerical approach for the incompressible surface Navier-Stokes
equation. The approach is based on the covariant form and uses discrete
exterior calculus (DEC) in space and a semi-implicit discretization in time.
The discretization is described in detail and related to finite difference
schemes on staggered grids in flat space for which we demonstrate second order
convergence. We compare computational results with a vorticity-stream function
approach for surfaces with genus 0 and demonstrate the interplay between
topology, geometry and flow properties. Our discretization also allows to
handle harmonic vector fields, which we demonstrate on a torus.