title:
ParMAC: distributed optimisation of nested functions, with application
  to learning binary autoencoders

abstract:
  Many powerful machine learning models are based on the composition of
multiple processing layers, such as deep nets, which gives rise to nonconvex
objective functions. A general, recent approach to optimise such "nested"
functions is the method of auxiliary coordinates (MAC). MAC introduces an
auxiliary coordinate for each data point in order to decouple the nested model
into independent submodels. This decomposes the optimisation into steps that
alternate between training single layers and updating the coordinates. It has
the advantage that it reuses existing single-layer algorithms, introduces
parallelism, and does not need to use chain-rule gradients, so it works with
nondifferentiable layers. With large-scale problems, or when distributing the
computation is necessary for faster training, the dataset may not fit in a
single machine. It is then essential to limit the amount of communication
between machines so it does not obliterate the benefit of parallelism. We
describe a general way to achieve this, ParMAC. ParMAC works on a cluster of
processing machines with a circular topology and alternates two steps until
convergence: one step trains the submodels in parallel using stochastic
updates, and the other trains the coordinates in parallel. Only submodel
parameters, no data or coordinates, are ever communicated between machines.
ParMAC exhibits high parallelism, low communication overhead, and facilitates
data shuffling, load balancing, fault tolerance and streaming data processing.
We study the convergence of ParMAC and propose a theoretical model of its
runtime and parallel speedup. We develop ParMAC to learn binary autoencoders
for fast, approximate image retrieval. We implement it in MPI in a distributed
system and demonstrate nearly perfect speedups in a 128-processor cluster with
a training set of 100 million high-dimensional points.


title:
The Mathematical Foundations for Mapping Policies to Network Devices
  (Technical Report)

abstract:
  A common requirement in policy specification languages is the ability to map
policies to the underlying network devices. Doing so, in a provably correct
way, is important in a security policy context, so administrators can be
confident of the level of protection provided by the policies for their
networks. Existing policy languages allow policy composition but lack formal
semantics to allocate policy to network devices.
  Our research tackles this from first principles: we ask how network policies
can be described at a high-level, independent of firewall-vendor and network
minutiae. We identify the algebraic requirements of the policy mapping process
and propose semantic foundations to formally verify if a policy is implemented
by the correct set of policy-arbiters. We show the value of our proposed
algebras in maintaining concise network-device configurations by applying them
to real-world networks.


title:
Image segmentation based on the hybrid total variation model and the
  K-means clustering strategy

abstract:
  The performance of image segmentation highly relies on the original inputting
image. When the image is contaminated by some noises or blurs, we can not
obtain the efficient segmentation result by using direct segmentation methods.
In order to efficiently segment the contaminated image, this paper proposes a
two step method based on the hybrid total variation model with a box constraint
and the K-means clustering method. In the first step, the hybrid model is based
on the weighted convex combination between the total variation functional and
the high-order total variation as the regularization term to obtain the
original clustering data. In order to deal with non-smooth regularization term,
we solve this model by employing the alternating split Bregman method. Then, in
the second step, the segmentation can be obtained by thresholding this
clustering data into different phases, where the thresholds can be given by
using the K-means clustering method. Numerical comparisons show that our
proposed model can provide more efficient segmentation results dealing with the
noise image and blurring image.


title: High-field electron transport in bulk ZnO

abstract:
  Current-voltage dependence is measured in (Ga,Sb)-doped ZnO up to 150 kV/cm
electric fields. A channel temperature is controlled by applying relatively
short (few ns) voltage pulses to two-terminal samples. The dependence of
electron drift velocity on electron density ranging from 1.42$\times$10$^{17}$
cm$^{-3}$ to 1.3$\times$10$^{20}$ cm$^{-3}$ at a given electric field is
deduced after estimation of the sample contact resistance and the Hall electron
mobility. Manifestation of the highest electron drift velocity up to
$\sim$1.5$\times$10$^{7}$ cm/s is estimated for electron density of
1.42$\times$10$^{17}$ cm$^{-3}$ and is in agreement with Monte Carlo simulation
when hot-phonon lifetime is below 1 ps. A local drift velocity maximum is
observed at $\sim$1.1$\times$10$^{19}$ cm$^{-3}$ and is in agreement with
ultra-fast hot phonon decay.


title: JUNO: a General Purpose Experiment for Neutrino Physics

abstract:
  JUNO is a 20 kt Liquid Scintillator Antineutrino Detector currently under
construction in the south of China. This report reviews JUNO's physics
programme related to all neutrino sources but reactor antineutrinos, namely
neutrinos from supernova burst, solar neutrinos and geoneutrinos.


title:
Time domain simulations of preliminary breakdown pulses in natural
  lightning

abstract:
  Lightning discharge is a complicated process with relevant physical scales
spanning many orders of magnitude. In an effort to understand the
electrodynamics of lightning and connect physical properties of the channel to
observed behavior, we construct a simulation of charge and current flow on a
narrow conducting channel embedded in three-dimensional space with the time
domain electric field integral equation, the method of moments, and the
thin-wire approximation. The method includes approximate treatment of
resistance evolution due to lightning channel heating and the corona sheath of
charge surrounding the lightning channel. Focusing our attention on preliminary
breakdown in natural lightning by simulating stepwise channel extension with a
simplified geometry, our simulation reproduces the broad features observed in
data collected with the Huntsville Alabama Marx Meter Array. Some deviations in
pulse shape details are evident, suggesting future work focusing on the
detailed properties of the stepping mechanism.


title:
Temperature spectra of interstellar dust grains heated by cosmic-rays I:
  translucent clouds

abstract:
  Heating of whole interstellar dust grains by cosmic-ray (CR) particles
affects the gas-grain chemistry in molecular clouds by promoting molecule
desorption, diffusion, and chemical reactions on grain surfaces. The frequency
of such heating $f_T$, s$^{-1}$, determines how often a certain temperature
$T_{\rm CR}$, K, is reached for grains hit by CR particles. This study aims to
provide astrochemists with comprehensive and updated dataset on the CR-induced
whole-grain heating. We present calculations of $f_T$ and $T_{\rm CR}$ spectra
for bare olivine grains with radius $a$ of 0.05; 0.1; 0.2 $\mu$m, and such
grains covered with ice mantles of thickness 0.1$a$ and 0.3$a$. Grain shape and
structure effects are considered, as well as 30 CR elemental constituents with
an updated energy spectrum corresponding to a translucent cloud with $A_V=2$
mag. Energy deposition by CRs in grain material was calculated with the SRIM
program. We report full $T_{\rm CR}$ spectra for all nine grain types and
consider initial grain temperatures of 10 K and 20 K. We also provide
frequencies for a range of minimum $T_{\rm CR}$ values. The calculated dataset
can be simply and flexibly implemented in astrochemical models. The results
show that, in the case of translucent clouds, the currently adopted rate for
heating of whole grains to temperatures in excess of 70 K is underestimated by
approximately two orders of magnitude in astrochemical numerical simulations.
Additionally, grains are heated by CRs to modest temperatures (20--30 K) with
intervals of a few years, which reduces the possibility of ice chemical
explosions.


title:
Phase transition and thermodynamic geometry of $f(R)$ AdS black holes in
  the grand canonical ensemble

abstract:
  The phase transition of four-dimensional charged AdS black hole solution in
the $R+f(R)$ gravity with constant curvature is investigated in the grand
canonical ensemble, where we find novel characteristics quite different from
that in canonical ensemble. There exists no critical point for $T-S$ curve
while in former research critical point was found for both the $T-S$ curve and
$T-r_+$ curve when the electric charge of $f(R)$ black holes is kept fixed.
Moreover, we derive the explicit expression for the specific heat, the analog
of volume expansion coefficient and isothermal compressibility coefficient when
the electric potential of $f(R)$ AdS black hole is fixed. The specific heat
$C_\Phi$ encounters a divergence when $0<\Phi<b$ while there is no divergence
for the case $\Phi>b$. This finding also differs from the result in the
canonical ensemble, where there may be two, one or no divergence points for the
specific heat $C_Q$. To examine the phase structure newly found in the grand
canonical ensemble, we appeal to the well-known thermodynamic geometry tools
and derive the analytic expressions for both the Weinhold scalar curvature and
Ruppeiner scalar curvature. It is shown that they diverge exactly where the
specific heat $C_\Phi$ diverges.


title:
Measurement of antineutrino oscillation with the full detector
  configuration at Daya Bay

abstract:
  In this poster, we present the latest measurement of electron antineutrino
disappearance using the fully constructed Daya Bay Reactor Neutrino Experiment.
A total exposure of $6.9 \times 10^5$ GW$_{\mathrm{th}}$ ton days was achieved
in November 2013 after 617 day of data taking. The most precise estimates to
date of the neutrino mass and mixing parameters $|\Delta \mathrm{m}^2_{ee}|$
and $\sin^2 2 \theta_{13}$ were obtained with an analysis of the relative
antineutrino rates and energy spectra between detectors. The value of the two
parameters was found to be $\sin^2 2 \theta_{13} = 0.084 \pm 0.005$ and
$|\Delta \mathrm{m}^2_{ee}| = (2.42 \pm 0.11) \times 10^{-3}\,\mathrm{eV}^2$.
This report focuses in particular on describing how improvements in the
calibration and in the energy response model contributed to achieve this
result.


title:
Formation of tiny particles and their extended shapes-Origin of physics
  and chemistry of materials

abstract:
  Tiny-sized particles under the scheme of monolayer assembly, comprising gold
atoms, developed at a different processing time in a pulse-based process. For a
different processing time, atoms bind into different tiny particles under the
placing packets of nanoshape energy where they elongate as per arrangement and
when in one-dimensional arrays, they convert into structures of smooth
elements. For different processing time and where tiny particles possess
triangular-shape, they pack to develop extended shapes where development rate
of an anisotropic particle is not more than millisecond time. Increasing the
processing time of solution upto certain duration increases the number of
developing tiny particles in a triangular-shape, so, their extended shapes
also. Uniformly adjacent-orientation of electrons in atoms of tiny-shaped
particle is because of exerting uniform surface force along their opposite
poles as per gained potential energy where stretching of their clamped energy
knots is remained orientational-based. At a different processing time,
inter-spacing distance of spotted intensity spots in selective area photons
reflection patterns of particles is remained the same as for the case of their
structures of smooth elements visualized through transmission microscope
high-resolution images. When the forceful coinciding of two parallel structures
of smooth elements is occurred, they bind into single element structure of
smooth element by a bit overlying inner sides, thus, giving its double width
where certain filled state electrons and unfilled energy knots belonging to
sides of elongated atoms of parallel structures of smooth elements coordinate
to adhere. This study discusses the formation of tiny particles following by
their extended shapes at different processing time of gold solution while
employing a pulse-based electron-photon solution-interface process where they
become the origin


title:
Minimax Rate-Optimal Estimation of Divergences between Discrete
  Distributions

abstract:
  We study the minimax estimation of $\alpha$-divergences between discrete
distributions for integer $\alpha\ge 1$, which include the Kullback--Leibler
divergence and the $\chi^2$-divergences as special examples. Dropping the usual
theoretical tricks to acquire independence, we construct the first minimax
rate-optimal estimator which does not require any Poissonization, sample
splitting, or explicit construction of approximating polynomials. The estimator
uses a hybrid approach which solves a problem-independent linear program based
on moment matching in the non-smooth regime, and applies a problem-dependent
bias-corrected plug-in estimator in the smooth regime, with a soft decision
boundary between these regimes.


title: Zigzag Decodable Fountain Codes

abstract:
  This paper proposes a fountain coding system which has lower space decoding
complexity and lower decoding erasure rate than the Raptor coding systems. The
main idea of the proposed fountain code is employing shift and exclusive OR to
generate the output packets. This technique is known as the zigzag decodable
code, which is efficiently decoded by the zigzag decoder. In other words, we
propose a fountain code based on the zigzag decodable code in this paper.
Moreover, we analyze the overhead for the received packets, decoding erasure
rate, decoding complexity, and asymptotic overhead of the proposed fountain
code. As the result, we show that the proposed fountain code outperforms the
Raptor codes in terms of the overhead and decoding erasure rate. Simulation
results show that the proposed fountain coding system outperforms Raptor coding
system in terms of the overhead and the space decoding complexity.


title:
Towards a measurement of the effective gauge field and the Born-Huang
  potential with atoms in chip traps

abstract:
  We study magnetic traps with very high trap frequencies where the spin is
coupled to the motion of the atom. This allows us to investigate how the
Born-Oppenheimer approximation fails and how effective magnetic and electric
fields appear as the consequence of the non-adiabatic dynamics. The results are
based on exact numerical diagonalization of the full Hamiltonian describing the
coupling between the internal and external degrees of freedom. The position in
energy and the decay rate of the trapping states correspond to the imaginary
part of the resonances of this Hamiltonian and are computed using the complex
rotation method.


title:
Chemical ordering in Pd$_{81}$Ge$_{19}$ metallic glass studied by
  reverse Monte-Carlo modelling of XRD, ND and EXAFS experimental data

abstract:
  Pd$_{81}$Ge$_{19}$ metallic glass was investigated by neutron diffraction,
X-ray diffraction and extended X-ray absorption fine structure spectroscopy
(EXAFS) at the Ge K-edge. Large scale structural models were obtained by
fitting the three measurements simultaneously in the framework of the reverse
Monte Carlo simulation technique. It was found that the experimental data sets
can be adequately fitted without Ge-Ge nearest neighbours. Mean Pd-Pd and Pd-Ge
distances are 2.80$\pm$0.02 {\AA} and 2.50$\pm$0.02 {\AA}, respectively. The
total average coordination number of Pd is 12.1$\pm$0.5 while Ge is surrounded
by 10.6$\pm$1.1 Pd atoms. The coordination numbers calculated from partial pair
correlation functions were compared to those obtained by Voronoi tessellation
method. It was found that the latter technique overestimates the number of
nearest neighbours by about 20% due to the significant contribution of distant
pairs.

categories: cond-mat.soft cond-mat.dis-nn cond-mat.mtrl-sci physics.chem-ph


title: Control of Memory, Active Perception, and Action in Minecraft

abstract:
  In this paper, we introduce a new set of reinforcement learning (RL) tasks in
Minecraft (a flexible 3D world). We then use these tasks to systematically
compare and contrast existing deep reinforcement learning (DRL) architectures
with our new memory-based DRL architectures. These tasks are designed to
emphasize, in a controllable manner, issues that pose challenges for RL methods
including partial observability (due to first-person visual observations),
delayed rewards, high-dimensional visual observations, and the need to use
active perception in a correct manner so as to perform well in the tasks. While
these tasks are conceptually simple to describe, by virtue of having all of
these challenges simultaneously they are difficult for current DRL
architectures. Additionally, we evaluate the generalization performance of the
architectures on environments not used during training. The experimental
results show that our new architectures generalize to unseen environments
better than existing DRL architectures.


title:
Objective realism and freedom of choice in relativistic quantum field
  theory

abstract:
  Traditional Bell's argument shows that freedom of choice is inconsistent with
quantum realism if lack of signaling and sufficiently fast choices and readouts
are assumed. While no-signaling alone is a consequence of special relativity,
this is not the case of spacetime location of choice and readout. Here we
attempt to incorporate freedom of choice into quantum objective realism relying
solely on relativistic quantum field theory. We conclude that this is
impossible without breaking relativistic invariance and put forward the
possibility of signaling faster than light, which cannot be excluded if an
ultimate theory violates relativity.


title: Cosmic Shear Bias and Calibration in Cosmic Shear Studies

abstract:
  With the advent of large-scale weak lensing surveys there is a need to
understand how realistic, scale-dependent systematics bias cosmic shear and
dark energy measurements, and how they can be removed. Here we describe how
spatial variations in the amplitude and orientation of realistic image
distortions convolve with the measured shear field, mixing the even-parity
convergence and odd-parity modes, and bias the shear power spectrum. Many of
these biases can be removed by calibration to external data, the survey itself,
or by modelling in simulations. The uncertainty in the calibration must be
marginalised over and we calculate how this propagates into parameter
estimation, degrading the dark energy Figure-of-Merit. We find that noise-like
biases affect dark energy measurements the most, while spikes in the bias power
have the least impact, reflecting their correlation with the effect of
cosmological parameters. We argue that in order to remove systematic biases in
cosmic shear surveys and maintain statistical power effort should be put into
improving the accuracy of the bias calibration rather than minimising the size
of the bias. In general, this appears to be a weaker condition for bias
removal. We also investigate how to minimise the size of the calibration set
for a fixed reduction in the Figure-of-Merit. These results can be used to
model the effect of biases and calibration on a cosmic shear survey accurately,
assess their impact on the measurement of modified gravity and dark energy
models, and to optimise surveys and calibration requirements.


title:
Classification under Streaming Emerging New Classes: A Solution using
  Completely Random Trees

abstract:
  This paper investigates an important problem in stream mining, i.e.,
classification under streaming emerging new classes or SENC. The common
approach is to treat it as a classification problem and solve it using either a
supervised learner or a semi-supervised learner. We propose an alternative
approach by using unsupervised learning as the basis to solve this problem. The
SENC problem can be decomposed into three sub problems: detecting emerging new
classes, classifying for known classes, and updating models to enable
classification of instances of the new class and detection of more emerging new
classes. The proposed method employs completely random trees which have been
shown to work well in unsupervised learning and supervised learning
independently in the literature. This is the first time, as far as we know,
that completely random trees are used as a single common core to solve all
three sub problems: unsupervised learning, supervised learning and model update
in data streams. We show that the proposed unsupervised-learning-focused method
often achieves significantly better outcomes than existing
classification-focused methods.


title: S-Noetherian generalized power series rings

abstract:
  Let R be a ring with identity, (M;\leq) a commutative positive strictly
ordered monoid and w_m an automorphism for each m \in M . The skew generalized
power series ring R[[M,w]] is a common generalization of (skew) polynomial
rings, (skew) power series rings, (skew) Laurent polynomial rings, (skew) group
rings, and Mal'cev Neumann Laurent series rings. If S\subset R is a
multiplicative set, then R is called right S-Noetherian, if for each ideal I of
R, Is \subseteq J\subseteq I for some s\in S and some finitely generated right
ideal J . Unifying and generalizing a number of known results, we study
transfers of S-Noetherian property to the ring R[[M,w]]. We also show that the
ring R[[M,w]] is left Noetherian if and only if R is left Noetherian and M is
finitely generated. Generalizing a result of Anderson and Dumitrescu, we show
that,when S\subset R is a-anti-Archimedean multiplicative set with a an
automorphism of R, then R is right S-Noetherian if and only if the skew
polynomial ring R[x,a] is right S-Noetherian.


title: Amenability of groups is characterized by Myhill's Theorem

abstract:
  We prove a converse to Myhill's "Garden-of-Eden" theorem and obtain in this
manner a characterization of amenability in terms of cellular automata: "A
group $G$ is amenable if and only if every cellular automaton with carrier $G$
that has gardens of Eden also has mutually erasable patterns."
  This answers a question by Schupp, and solves a conjecture by
Ceccherini-Silberstein, Mach\`i and Scarabotti.
  An appendix by Dawid Kielak proves that group rings without zero divisors are
Ore domains precisely when the group is amenable, answering a conjecture
attributed to Guba.


title:
The effect of frequency chirping on electron-positron pair production in
  the one- and two-color laser pulse fields

abstract:
  The effect of the frequency chirping on momentum spectrum and pair production
rate in one- and two-color laser pulse fields is investigated by solving the
quantum Vlasov equation. A small frequency chirp shifts the momentum spectrum
along the momentum axis. The positive and negative frequency chirp parameters
play the same role in increasing the pair number density. The sign change of
frequency chirp parameter at the moment $t=0$ leads pulse shape and momentum
spectrum to be symmetric, and the number density to be increased. The number
density of produced pairs in the two-color pulse field is much higher than that
in the one-color pulse field and the larger frequency chirp pulse field
dominates more strongly. In the two-color pulse fields, the relation between
the frequency ratio of two colors and the number density is not sensitive to
the parameters of small frequency chirp added in either low frequency strong
field or high frequency weak field but sensitive to the parameters of large
frequency chirp added in high frequency weak field.


title:
A positivity conjecture related first positive rank and crank moments
  for overpartitions

abstract:
  Recently, Andrews, Chan, Kim and Osburn introduced a $q$-series $h(q)$ for
the study of the first positive rank and crank moments for overpartitions. They
conjectured that for all integers $m \geq 3$, \begin{equation*}\label{hqcon}
\frac{1}{(q)_{\infty}} (h(q) - m h(q^{m})) \end{equation*} has positive power
series coefficients for all powers of $q$. Byungchan Kim, Eunmi Kim and
Jeehyeon Seo provided a combinatorial interpretation and proved it is
asymptotically true by circle method. In this note, we show this conjecture is
true if $m$ is any positive power of $2$, and we show that in order to prove
this conjecture, it is only to prove it for all primes $m$. Moreover we give a
stronger conjecture. Our method is very simple and completely different from
that of Kim et al.


title:
Hyperspectral Image Classification with Support Vector Machines on
  Kernel Distribution Embeddings

abstract:
  We propose a novel approach for pixel classification in hyperspectral images,
leveraging on both the spatial and spectral information in the data. The
introduced method relies on a recently proposed framework for learning on
distributions -- by representing them with mean elements in reproducing kernel
Hilbert spaces (RKHS) and formulating a classification algorithm therein. In
particular, we associate each pixel to an empirical distribution of its
neighbouring pixels, a judicious representation of which in an RKHS, in
conjunction with the spectral information contained in the pixel itself, give a
new explicit set of features that can be fed into a suite of standard
classification techniques -- we opt for a well-established framework of support
vector machines (SVM). Furthermore, the computational complexity is reduced via
random Fourier features formalism. We study the consistency and the convergence
rates of the proposed method and the experiments demonstrate strong performance
on hyperspectral data with gains in comparison to the state-of-the-art results.


title: The role of surface defects in the adsorption of methanol on Fe3O4(001)

abstract:
  The adsorption of methanol (CH3OH) at the Fe3O4(001)-c(2x2) surface was
studied using X-ray photoelectron spectroscopy (XPS), scanning tunneling
microscopy (STM), and temperature-programmed desorption (TPD). CH3OH adsorbs
exclusively at surface defects sites at room temperature to form hydroxyl
groups and methoxy (CH3O) species. Active sites are identified as step edges,
iron adatoms, antiphase domain boundaries in the c(2x2) reconstruction, and
above Fe atoms incorporated in the subsurface. In TPD, recombinative desorption
is observed around 300 K, and a disproportionation reaction to form methanol
and formaldehyde occurs at 470 K.


title: Detector Control System and Efficiency Performance for CMS RPC at GIF++

abstract:
  In the framework of the High Luminosity LHC upgrade program, the CMS muon
group built several different RPC prototypes that are now under test at the new
CERN Gamma Irradiation Facility (GIF++). A dedicated Detector Control System
has been developed using the WinCC-OA tool to control and monitor these
prototype detectors and to store the measured parameters data. Preliminary
efficiency studies that set the base performance measurements of CMS RPC for
starting aging studies are also presented.


title: Duality theorems for blocks and tangles in graphs

abstract:
  We prove a duality theorem applicable to a a wide range of specialisations,
as well as to some generalisations, of tangles in graphs. It generalises the
classical tangle duality theorem of Robertson and Seymour, which says that
every graph either has a large-order tangle or a certain low-width
tree-decomposition witnessing that it cannot have such a tangle.
  Our result also yields duality theorems for profiles and for $k$-blocks. This
solves a problem studied, but not solved, by Diestel and Oum and answers an
earlier question of Carmesin, Diestel, Hamann and Hundertmark.


title:
Capturing non-local interaction effects in the Hubbard model: optimal
  mappings and limits of applicability

abstract:
  We investigate the Peierls-Feynman-Bogoliubov variational principle to map
Hubbard models with nonlocal interactions to effective models with only local
interactions. We study the renormalization of the local interaction induced by
nearest-neighbor interaction and assess the quality of the effective Hubbard
models in reproducing observables of the corresponding extended Hubbard models.
We compare the renormalization of the local interactions as obtained from
numerically exact determinant Quantum Monte Carlo to approximate but more
generally applicable calculations using dual boson, dynamical mean field
theory, and the random phase approximation. These more approximate approaches
are crucial for any application with real materials in mind. Furthermore, we
use the dual boson method to calculate observables of the extended Hubbard
models directly and benchmark these against determinant Quantum Monte Carlo
simulations of the effective Hubbard model.


title: On edges not in monochromatic copies of a fixed bipartite graph

abstract:
  Let $H$ be a fixed graph. Denote $f(n,H)$ to be the maximum number of edges
not contained in any monochromatic copy of $H$ in a 2-edge-coloring of the
complete graph $K_n$, and $ex(n,H)$ to be the {\it Tur\'an number} of $H$. An
easy lower bound shows $f(n,H)\ge ex(n,H)$ for any $H$ and $n$. In \cite{KS2},
Keevash and Sudakov proved that if $H$ is an edge-color-critical graph or
$C_4$, then $f(n,H)= ex(n,H)$ holds for large $n$, and they asked if this
equality holds for any graph $H$ when $n$ is sufficiently large. In this paper,
we provide an affirmative answer to this problem for an abundant infinite
family of bipartite graphs $H$, including all even cycles and complete
bipartite graphs $K_{s,t}$ for $t>s^2-3s+3$ or $(s,t)\in\{(3,3),(4,7)\}$. In
addition, our proof shows that for all such $H$, the 2-edge-coloring $c$ of
$K_n$ achieves the maximum number $f(n,H)$ if and only if one of the color
classes in $c$ induces an extremal graph for $ex(n,H)$. We also obtain a
multi-coloring generalization for bipartite graphs. Some related problems are
discussed in the final section.


title: Thermodynamic Emergence of a Brownian Motor

abstract:
  Human-created engines and evolutionarily optimized molecular motors exhibit
sophisticated design in order to harvest chemical or thermal energy for
generating unidirectional motion. The complexity of these motors makes their
random emergence unlikely. Molecules capable of locomotion, however, seem to be
essential to the creation of the first self-replicator and initiation of
Darwinian evolution, posing a question of the physical mechanism that can
facilitate emergence of directed motion in an isotropic environment. Here we
show a universal thermodynamic mechanism for spontaneous emergence of motor
abilities in a mechanical system. A non-equilibrium system with multiple
degrees of freedom develops symmetry breaking that favors rectification of
environmental thermal fluctuations. The corresponding velocities and its
fluctuations are calculated. Homochirality of living matter is explained as
chirality breaking resulting from the emergence of a motor. Universality of the
results provides a general extension of the Onsager relations to the non-linear
regime.


title: Index bounds for free boundary minimal surfaces of convex bodies

abstract:
  In this paper, we give a relationship between the eigenvalues of the Hodge
Laplacian and the eigenvalues of the Jacobi operator for a free boundary
minimal hypersurface of a Euclidean convex body. We then use this relationship
to obtain new index bounds for such minimal hypersurfaces in terms of their
topology. In particular, we show that the index of a free boundary minimal
surface in a convex domain in $\mathbb{R}^3$ tends to infinity as its genus or
the number of boundary components tends to infinity.


title:
Effect of the drag force on the orbital motion of the broad-line region
  clouds

abstract:
  We investigate orbital motion of cold clouds in the broad line region of
active galactic nuclei subject to the gravity of a black hole and a force due
to a nonisotropic central source and a drag force proportional to the velocity
square. The intercloud is described using the standard solutions for the
advection-dominated accretion flows. Orbit of a cloud decays because of the
drag force, but the typical time scale of falling of clouds onto the central
black hole is shorter comparing to the linear drag case. This time scale is
calculated when a cloud is moving through a static or rotating intercloud. We
show that when the drag force is a quadratic function of the velocity,
irrespective of the initial conditions and other input parameters, clouds will
generally fall onto the central region much faster than the age of whole system
and since cold clouds present in most of the broad line regions, we suggest
that mechanisms for continuous creation of the clouds must operate in these
systems.


title: The Koszul property for spaces of quadrics of codimension three

abstract:
  In this paper we prove that, if $\mathbb{k}$ is an algebraically closed field
of characteristic different from 2, almost all quadratic standard graded
$\mathbb{k}$-algebras $R$ such that $\dim_{\mathbb{k}}R_2 = 3$ are Koszul. More
precisely, up to graded $\mathbb{k}$-algebra homomorphisms and trivial fiber
extensions, we find out that only two (or three, when the characteristic of
$\mathbb{k}$ is 3) algebras of this kind are non-Koszul.
  Moreover, we show that there exist nontrivial quadratic standard graded
$\mathbb{k}$-algebras with $\dim_{\mathbb{k}}R_1 = 4$, $\dim_{\mathbb{k}}R_2 =
3$ that are Koszul but do not admit a Gr\"obner basis of quadrics even after a
change of coordinates, thus settling in the negative a question asked by Conca.


title: On certain labelled directed graphs of symbolic dynamics

abstract:
  We describe classes of semisynchronizing, non-synchronizing subshifts, that
are closed under topological conjugacy. The subshifts that belong to these
classes satisfy a strong hypothesis of context-freeness and are canonically
presented by means of Shannon graphs that have the structure of a pda.


title:
Optimal analysis of ultra broadband energy-time entanglement for high
  bit-rate dense wavelength division multiplexed quantum networks

abstract:
  We demonstrate an experimental method for measuring energy-time entanglement
over almost 80 nm spectral bandwidth in a single shot with a quantum bit error
rate below 0.5%. Our scheme is extremely cost-effective and efficient in terms
of resources as it employs only one source of entangled photons and one fixed
unbalanced interferometer per phase-coded analysis basis. We show that the
maximum analysis spectral bandwidth is obtained when the analysis
interferometers are properly unbalanced, a strategy which can be
straightforwardly applied to most of today's experiments based on energy-time
and time-bin entanglement. Our scheme has therefore a great potential for
boosting bit rates and reducing the resource overhead of future
entanglement-based quantum key distribution systems.


title:
Sparse matrix factorizations for fast linear solvers with application to
  Laplacian systems

abstract:
  In solving a linear system with iterative methods, one is usually confronted
with the dilemma of having to choose between cheap, inefficient iterates over
sparse search directions (e.g., coordinate descent), or expensive iterates in
well-chosen search directions (e.g., conjugate gradients). In this paper, we
propose to interpolate between these two extremes, and show how to perform
cheap iterations along non-sparse search directions, provided that these
directions can be extracted from a new kind of sparse factorization. For
example, if the search directions are the columns of a hierarchical matrix,
then the cost of each iteration is typically logarithmic in the number of
variables. Using some graph-theoretical results on low-stretch spanning trees,
we deduce as a special case a nearly-linear time algorithm to approximate the
minimal norm solution of a linear system $Bx= b$ where $B$ is the incidence
matrix of a graph. We thereby can connect our results to recently proposed
nearly-linear time solvers for Laplacian systems, which emerge here as a
particular application of our sparse matrix factorization.


title:
Out-of-equilibrium Kondo Effect in a Quantum Dot: Interplay of Magnetic
  Field and Spin Accumulation

abstract:
  We present a theoretical study of low temperature nonequilibrium transport
through an interacting quantum dot in the presence of Zeeman magnetic field and
current injection into one of its leads. By using a self-consistent
renormalized equation of motion approach, we show that the injection of a
spin-polarized current leads to a modulation of the Zeeman splitting of the
Kondo peak in the differential conductance. We find that an appropriate amount
of spin accumulation in the lead can restore the Kondo peak by compensating the
splitting due to magnetic field. By contrast when the injected current is
spin-unpolarized, we establish that both Zeeman-split Kondo peaks are equally
shifted and the splitting remains unchanged. Our results quantitatively explain
the experimental findings reported in KOBAYASHI T. et al., Phys. Rev. Lett.
104, 036804 (2010). These features could be nicely exploited for the control
and manipulation of spin in nanoelectronic and spintronic devices.


title: Reverse isoperimetric inequality in two-dimensional Alexandrov spaces

abstract:
  We prove a reverse isoperimetric inequality for domains homeomorphic to a
disc with the boundary of curvature bounded below lying in two-dimensional
Alexandrov spaces of curvature $\geqslant c$. We also study the equality case.


title:
Particle-in-Cell simulation of two-dimensional electron velocity shear
  driven instability in relativistic domain

abstract:
  We carry out Particle-in-Cell (PIC) simulations to study the instabilities
associated with a 2-D sheared electron flow configuration against a
neutralizing background of ions. Both weak and strong relativistic flow
velocities are considered. In the weakly relativistic case, we observe the
development of electromagnetic Kelvin Helmholtz instability with similar
characteristics as that predicted by the electron Magnetohydrodynamic (EMHD)
model. On other hand, in strong relativistic case the compressibility effects
of electron fluid dominate and introduce upper hybrid electrostatic
oscillations transverse to the flow which are very distinct from EMHD fluid
behaviour. In the nonlinear regime, both weak and strong relativistic cases
lead to turbulence with broad power law spectrum.


title:
Drag-driven instability of a dust layer in a magnetized protoplanetary
  disc

abstract:
  We study drag-driven instability in a protoplanetary disc consisting of a
layer of single-sized dust particles which are coupled to the magnetized gas
aerodynamically and the particle-to-gas feedback is included. We find a
dispersion relation for axisymmetric linear disturbances and growth rate of the
unstable modes are calculated numerically. While the secular gravitational
instability in the absence of particle-to-gas feedback predicts the dust layer
is unstable, magnetic fields significantly amplifies the instability if the
Toomre parameter for the gas component is fixed. We also show that even a weak
magnetic field is able to amplify the instability more or less irrespective of
the dust-gas coupling.


title:
New tools in GeoGebra offering novel opportunities to teach loci and
  envelopes

abstract:
  GeoGebra is an open source mathematics education software tool being used in
thousands of schools worldwide. Since version 4.2 (December 2012) it supports
symbolic computation of locus equations as a result of joint effort of
mathematicians and programmers helping the GeoGebra developer team. The joint
work, based on former researches, started in 2010 and continued until present
days, now enables fast locus and envelope computations even in a web browser in
full HTML5 mode. Thus, classroom demonstrations and deeper investigations of
dynamic analytical geometry are ready to use on tablets or smartphones as well.
  In our paper we consider some typical secondary school topics where
investigating loci is a natural way of defining mathematical objects. We
discuss the technical possibilities in GeoGebra by using the new commands
LocusEquation and Envelope, showing through different examples how these
commands can enrich the learning of mathematics. The covered school topics
include definition of a parabola and other conics in different situations like
synthetic definitions or points and curves associated with a triangle. Despite
the fact that in most secondary schools, no other than quadratic curves are
discussed, simple generalization of some exercises, and also every day
problems, will smoothly introduce higher order algebraic curves. Thus our paper
mentions the cubic curve "strophoid" as locus of the orthocenter of a triangle
when one of the vertices moves on a circle. Also quartic "cardioid" and sextic
"nephroid" can be of every day interest when investigating mathematics in, say,
a coffee cup.
  We also focus on GeoGebra specific tips and tricks when constructing a
geometric figure to be available for getting the locus equation. Among others,
simplification and synthetization (via the intercept theorem) are mentioned.


title:
Gauge invariant gluon spin operator for spinless non-linear wave
  solutions

abstract:
  We consider non-linear wave type solutions with mass scale parameter and
vahished canonical spin density operator in a pure SU(2) quantum chtomodynamics
(QCD). A new stationary solution which can be treated as a system of static
Wu-Yang monopole dressed in off-diagonal gluon field is proposed. A remarkable
feature of such a solution is that it possesses a finite energy density
everywhere. All considered non-linear wave type solutions have common features:
presence of a mass scale parameter, non-vanishing projection of the color
magnetic field along the propagation direction and zero spin density. The last
property requires revision of the gauge invariant definition of the spin
density operator which supposed to be massless vector field in the classical
theory. We construct a gauge invariant definition of the classical gluon spin
density which is unique and Lorentz frame independent.


title: Stable spherically symmetric monopole field background in a pure QCD

abstract:
  We consider a stationary spherically symmetric monopole like solution with a
finite energy density in a pure quantum chromodynamics (QCD). The solution can
be treated as a static Wu-Yang monopole dressed in time dependent field
corresponding to off-diagonal gluons. We have proved that such a stationary
monopole field represents a background vacuum field of the QCD effective action
which is stable against quantum gluon fluctuations. This resolves a
long-standing problem of existence of a stable vacuum field in QCD and opens a
new avenue towards microscopic theory of the vacuum.


title: Non-relativistic anyons from holography

abstract:
  We study generic types of holographic matter residing in Lifshitz invariant
defect field theory as modeled by adding probe D-branes in the bulk black hole
spacetime characterized by dynamical exponent $z$ and with hyperscaling
violation exponent $\theta$. Our main focus will be on the collective
excitations of the dense matter in the presence of an external magnetic field.
Constraining the defect field theory to 2+1 dimensions, we will also allow the
gauge fields become dynamical and study the properties of a strongly coupled
anyonic fluid. We will deduce the universal properties of holographic matter
and find that the Einstein relation always holds.


title: Extreme properties of curves with bounded curvature on a sphere

abstract:
  We give a sharp lower bound on the area of the domain enclosed by an embedded
curve lying on a two-dimensional sphere, provided that geodesic curvature of
this curve is bounded from below. Furthermore, we prove some dual inequalities
for convex curves whose curvatures are bounded from above.


title: On the Study of Non-Relativistic Spin Half-Integer Systems

abstract:
  In this article, after introducing appropriate equation for non-relativistic
spin half-integer system, Lagrange density of such system has been derived.
Then time-evolution of this system in presence of a time-dependent interaction
has been done


title: A two-dimensional spin field-effect transistor

abstract:
  The integration of the spin degree of freedom in charge-based electronic
devices has revolutionised both sensing and memory capability in
microelectronics. Further development in spintronic devices requires electrical
manipulation of spin current for logic operations. The approach followed so
far, inspired by the seminal proposal of the Datta and Das spin modulator, has
relied on the spin-orbit field as a medium for electrical control of the spin
state. However, the still standing challenge is to find a material whose
spin-orbit-coupling (SOC) is weak enough to transport spins over long
distances, while also being strong enough to allow their electrical
manipulation. Here we demonstrate a radically different approach by engineering
a heterostructure from atomically thin crystals, which are "glued" by weak van
der Waals (vdW) forces and which combine the superior spin transport properties
of graphene with the strong SOC of the semiconducting MoS$_{2}$. The spin
transport in the graphene channel is modulated between ON and OFF states by
tuning the spin absorption into the MoS$_{2}$ layer with a gate electrode. Our
demonstration of a spin field-effect transistor using two-dimensional (2D)
materials identifies a new route towards spin logic operations for beyond CMOS
technology.


title:
On the isotropic constant of random polytopes with vertices on an
  $\ell_p$-sphere

abstract:
  The symmetric convex hull of random points that are independent and
distributed according to the cone probability measure on the $\ell_p$-unit
sphere of $\mathbb R^n$ for some $1\leq p < \infty$ is considered. We prove
that these random polytopes have uniformly absolutely bounded isotropic
constants with overwhelming probability. This generalizes the result for the
Euclidean sphere ($p=2$) obtained by D. Alonso-Guti\'errez. The proof requires
several different tools including a probabilistic representation of the cone
measure due to G. Schechtman and J. Zinn and moment estimates for sums of
independent random variables with log-concave tails originating in the work of
E. Gluskin and S. Kwapie\'n.


title: The conjugation method in symplectic dynamics

abstract:
  We prove the existence of minimal symplectomorphisms and strictly ergodic
contactomorphisms on manifolds which admit a locally free
$\mathbb{S}^1$--action by symplectomorphisms and contactomorphisms,
respectively. The proof adapts the conjugation method, introduced by Anosov and
Katok, to the contact and symplectic setting.


title:
Modeling of the contrast-enhanced perfusion test in liver based on the
  multi-compartment flow in porous media

abstract:
  The paper deals with modeling the liver perfusion intended to improve
quantitative analysis of the tissue scans provided by the contrast-enhanced
computed tomography (CT). For this purpose, we developed a model of dynamic
transport of the contrast fluid through the hierarchies of the perfusion trees.
Conceptually, computed time-space distributions of the so-called tissue density
can be compared with the measured data obtained from CT; such a modeling
feedback can be used for model parameter identification. The blood flow is
characterized at several scales for which different models are used. Flows in
upper hierarchies represented by larger branching vessels are described using
simple 1D models based on the Bernoulli equation extended by correction terms
to respect the local pressure losses. To describe flows in smaller vessels and
in the tissue parenchyma, we propose a 3D continuum model of porous medium
defined in terms of hierarchically matched compartments characterized by
hydraulic permeabilities. The 1D models corresponding to the portal and hepatic
veins are coupled with the 3D model through point sources, or sinks. The
contrast fluid saturation is governed by transport equations adapted for the 1D
and 3D flow models. The complex perfusion model has been implemented using the
finite element and finite volume methods. We report numerical examples computed
for anatomically relevant geometries of the liver organ and of the principal
vascular trees. The simulated tissue density corresponding to the CT
examination output reflects a pathology modeled as a localized permeability
deficiency.


title: Sign-Reversal Coupling in Coupled-Resonator Optical Waveguide

abstract:
  Coupled-resonator optical waveguides (CROWs), which play a significant role
in modern photonics, achieve waveguiding through near-field coupling between
tightly localized resonators. The coupling factor, a critical parameter in CROW
theory, determines the coupling strength between two resonators and the
waveguiding dispersion of a CROW. However, the original CROW theory proposed by
Yariv et al. only demonstrated one value of coupling factor for a multipole
resonance mode. Here, by imaging the tight-binding Bloch waves on a CROW
consisting of designer-surface-plasmon resonators in the microwave regime, we
demonstrate that the coupling factor in the CROW theory can reverse its sign
for a multipole resonance mode. This determines two different waveguiding
dispersion curves in the same frequency range, experimentally confirmed by
matching Bloch wavevectors and frequencies in the CROW. Our study supplements
and extends the original CROW theory, and may find novel use in functional
photonic systems.


title:
Commensurate - Incommensurate vortex phase in a nanopatterned
  superconductor

abstract:
  Magneto-optical imaging studies on a high-quality Bi2Sr2CaCu2O8 single
crystal partially patterned with a triangular array of holes reveal enhanced
flux shielding in the patterned region of the sample. By mapping local magnetic
field and shielding current density distributions at different applied magnetic
fields and temperatures we determine the regime where pinning from the
patterned holes dominates over the intrinsic pinning in the sample. In this
regime, the flux density near the center of the patterned region is observed to
increase when the applied field is varied from below the matching field to just
above it, while significant magnetic field gradients are sustained in the
patterned region. Our measurements indicate heterogeneous pinning properties of
the vortex population, exhibiting signatures of both weak and strong pinning,
in the nanopatterned region of the superconductor.


title:
Quasi Monte Carlo integration and kernel-based function approximation on
  Grassmannians

abstract:
  Numerical integration and function approximation on compact Riemannian
manifolds based on eigenfunctions of the Laplace-Beltrami operator have been
widely studied in the recent literature. The standard example in numerical
experiments is the Euclidean sphere. Here, we derive numerically feasible
expressions for the approximation schemes on the Grassmannian manifold, and we
present the associated numerical experiments on the Grassmannian. Indeed, our
experiments illustrate and match the corresponding theoretical results in the
literature.


title:
The Xinglong 2.16-m Telescope: Current Instruments and Scientific
  Projects

abstract:
  The Xinglong 2.16-m reflector is the first 2-meter class astronomical
telescope in China. It was jointly designed and built by the Nanjing
Astronomical Instruments Factory (NAIF), Beijing Astronomical Observatory (now
National Astronomical Observatories, Chinese Academy of Sciences, NAOC) and
Institute of Automation, Chinese Academy of Sciences in 1989. It is
Ritchey-Chr\'{e}tien (R-C) reflector on an English equatorial mount and the
effective aperture is 2.16 meters. It had been the largest optical telescope in
China for $\sim18$ years until the Guoshoujing Telescope (also called Large Sky
Area Multi-Object Fiber Spectroscopic Telescope, LAMOST) and the Lijiang 2.4-m
telescope were built. At present, there are three main instruments on the
Cassegrain focus available: the Beijing Faint Object Spectrograph and Camera
(BFOSC) for direct imaging and low resolution ($R\sim500-2000$) spectroscopy,
the spectrograph made by Optomechanics Research Inc. (OMR) for low resolution
spectroscopy (the spectral resolutions are similar to those of BFOSC) and the
fiber-fed High Resolution Spectrograph (HRS, $R\sim30000-65000$). The telescope
is widely open to astronomers all over China as well as international
astronomical observers. Each year there are more than 40 ongoing observing
projects, including 6-8 key projects. Recently, some new techniques and
instruments (e.g., astro-frequency comb calibration system, polarimeter and
adaptive optics) have been or will be tested on the telescope to extend its
observing abilities.


title:
Photonic bands and defect modes in metallo-dielectric photonic crystal
  slabs

abstract:
  Photonic components based on structured metallic elements show great
potential for device applications where field enhancement and confinement of
the radiation on a subwavelength scale is required. In this paper we report a
detailed study of a prototypical metallo-dielectric photonic structure, where
features well known in the world of dielectric photonic crystals, like band
gaps and defect modes, are exported to the metallic counterpart, with
interesting applications to infrared science and technology, as for instance in
quantum well infrared photodetectors, narrow-band spectral filters, and
tailorable thermal emitters.


title:
Unravelling the noise: the discrimination of wave function collapse
  models under time-continuous measurements

abstract:
  Inspired by the notion that environmental noise is in principle observable,
whilst fundamental noise due to spontaneous localisation would not be, we study
the estimation of the diffusion parameter induced by wave function collapse
models under continuous monitoring of the environment. We take into account
finite measurement efficiencies and, in order to quantify the advantage granted
by monitoring, we analyse the quantum Fisher information associated with such a
diffusion parameter, identify optimal measurements in limiting cases, and
assess the performance of such measurements in more realistic conditions.


title:
Enumeration of Domino Tilings of an Aztec Rectangle with boundary
  defects

abstract:
  Helfgott and Gessel gave the number of domino tilings of an Aztec Rectangle
with defects of size one on the boundary of one side. In this paper we extend
this to the case of domino tilings of an Aztec Rectangle with defects on all
boundary sides.


title:
Infographics or Graphics+Text: Which Material is Best for Robust
  Learning?

abstract:
  Infographic is a type of information visualization that uses graphic design
to enhance human ability to identify patterns and trends. It is popularly used
to support spread of information. Yet, there are few studies that investigate
how infographics affect learning and how individual factors, such as learning
styles and enjoyment of the information affect infographics perception. In this
sense, this paper describes a case study performed in an online platform where
27 undergraduate students were randomly assigned to view infographics (n=14)
and graphics+text (n=13) as learning materials about the same content. They
also responded to questionnaires of enjoyment and learning styles. Our findings
indicate that there is no correlation between learning styles and post-test
scores. Furthermore, we did not find any difference regarding learning between
students using graphics or infographics. Nevertheless, for learners using
infographics, we found a significant and positive correlation between correct
answers and the positive self-assessment of enjoyment/ pleasure. We also
identified that students who used infographics keep their acquired information
longer than students who only used graphics+text, indicating that infographics
can better support robust learning.


title:
Randomization and The Pernicious Effects of Limited Budgets on Auction
  Experiments

abstract:
  Buyers (e.g., advertisers) often have limited financial and processing
resources, and so their participation in auctions is throttled. Changes to
auctions may affect bids or throttling and any change may affect what winners
pay. This paper shows that if an A/B experiment affects only bids, then the
observed treatment effect is unbiased when all the bidders in an auction are
randomly assigned to A or B but it can be severely biased otherwise, even in
the absence of throttling. Experiments that affect throttling algorithms can
also be badly biased, but the bias can be substantially reduced if the budget
for each advertiser in the experiment is allocated to separate pots for the A
and B arms of the experiment.


title: Weyl group $q$-Kreweras numbers and cyclic sieving

abstract:
  The paper concerns a definition for $q$-Kreweras numbers for finite Weyl
groups $W$, refining the $q$-Catalan numbers for $W$, and arising from work of
the second author. We give explicit formulas in all types for the $q$-Kreweras
numbers. In the classical types $A, B, C$, we also record formulas for the
$q$-Narayana numbers and in the process show that the formulas depend only on
the Weyl group (that is, they coincide in types $B$ and $C$). In addition we
verify that in the classical types $A,B,C,D$ that the $q$-Kreweras numbers obey
the expected cyclic sieving phenomena when evaluated at appropriate roots of
unity.


title: Highest rank of a polytope for $A_n$

abstract:
  We prove that the highest rank of a string C-group constructed from an
alternating group $Alt_n$ is 0 if $n=3, 4, 6, 7, 8$; 3 if $n=5$; 4 if $n=9$; 5
if $n=10$; 6 if $n=11$; and $\lfloor\frac{n-1}{2}\rfloor$ if $n\geq 12$. This
solves a conjecture made by the last three authors in 2012.


title:
Stability of time-delay reset systems with a nonlinear and time-varying
  base system

abstract:
  This work is devoted to investigate the stability properties of time-delay
reset systems. We present a Lyapunov-Krasovskii proposition, which generalizes
the available results in the literature, providing results for verifying the
stability of time-delay reset systems with nonlinear and time-varying base
system. We demonstrate the applicability of the proposed results in the
analysis of time-delay reset control systems, and an illustrative example with
nonlinear, time-varying base system.


title:
Quantum magnetic flux lines, BPS vortex zero modes, and one-loop string
  tension shifts

abstract:
  Spectral heat kernel/zeta function regularization procedures are employed in
this paper to control the divergences arising from vacuum fluctuations of
Bogomolnyi-Prasad-Sommerfield vortices in the Abelian Higgs model. Zero modes
of vortex fluctuations are the source of difficulties appearing when the
standard Gilkey-de Witt expansion is performed. A modified GdW expansion is
developed to diminish the impact of the infrared divergences due to the vortex
zero modes. With this new technique at our disposal we compute the one-loop
vortex mass shift in the planar AHM and the quantum corrections to the string
tension of the magnetic flux tubes living in three dimensions. In both cases it
is observed that weak repulsive forces surge between these classically non
interacting topological defects caused by vacuum quantum fluctuations.


title:
Hot spots and the hollowness of proton-proton interactions at high
  energies

abstract:
  We present a dynamical explanation of the hollowness effect observed in
proton-proton scattering at $\sqrt s\!=\!7$ TeV. This phenomenon, not observed
at lower energies, consists in a depletion of the inelasticity density at zero
impact parameter of the collision. Our analysis is based on three main
ingredients: we rely gluonic hot spots inside the proton as effective degrees
of freedom for the description of the scattering process. Next we assume that
some non-trivial correlation between the transverse positions of the hot spots
inside the proton exists. Finally we build the scattering amplitude from a
multiple scattering, Glauber-like series of collisions between hot spots. In
our approach, the onset of the hollowness effect is naturally explained as due
to the diffusion or growth of the hot spots in the transverse plane with
increasing collision energy.


title: Perspectives for proof unwinding by programming languages techniques

abstract:
  In this chapter, we propose some future directions of work, potentially
beneficial to Mathematics and its foundations, based on the recent import of
methodology from the theory of programming languages into proof theory. This
scientific essay, written for the audience of proof theorists as well as the
working mathematician, is not a survey of the field, but rather a personal view
of the author who hopes that it may inspire future and fellow researchers.


title:
Signatures and conditions for phase band crossings in periodically
  driven integrable systems

abstract:
  We present generic conditions for phase band crossings for a class of
periodically driven integrable systems represented by free fermionic models
subjected to arbitrary periodic drive protocols characterized by a frequency
$\omega_D$. These models provide a representation for the Ising and $XY$ models
in $d=1$, the Kitaev model in $d=2$, several kinds of superconductors, and
Dirac fermions in graphene and atop topological insulator surfaces. Our results
demonstrate that the presence of a critical point/region in the system
Hamiltonian (which is traversed at a finite rate during the dynamics) may
change the conditions for phase band crossings that occur at the critical
modes. We also show that for $d>1$, phase band crossings leave their imprint on
the equal-time off-diagonal fermionic correlation functions of these models;
the Fourier transforms of such correlation functions, $F_{\vec k_0}(
\omega_0)$, have maxima and minima at specific frequencies which can be
directly related to $\omega_D$ and the time at which the phase bands cross at
$\vec k = \vec k_0$. We discuss the significance of our results in the contexts
of generic Hamiltonians with $N>2$ phase bands and the underlying symmetry of
the driven Hamiltonian.


title: New super congruences involving Bernoulli and Euler polynomials

abstract:
  Let $p>3$ be a prime, and let $a$ be a rational p-adic integer with
$a\not\equiv 0\pmod p$. In this paper we establish congruences for
$$\sum_{k=1}^{(p-1)/2}\frac{\binom ak\binom{-1-a}k}k,
\quad\sum_{k=0}^{(p-1)/2}k\binom ak\binom{-1-a}k
\quad\text{and}\quad\sum_{k=0}^{(p-1)/2}\frac{\binom
ak\binom{-1-a}k}{2k-1}\pmod {p^2}$$ in terms of Bernoulli and Euler
polynomials. We also give some transformation formulas for congruences modulo
$p^2$.


title:
The K2-ESPRINT Project V: a short-period giant planet orbiting a
  subgiant star

abstract:
  We report on the discovery and characterization of the transiting planet
K2-39b (EPIC 206247743b). With an orbital period of 4.6 days, it is the
shortest-period planet orbiting a subgiant star known to date. Such planets are
rare, with only a handful of known cases. The reason for this is poorly
understood, but may reflect differences in planet occurrence around the
relatively high-mass stars that have been surveyed, or may be the result of
tidal destruction of such planets. K2-39 is an evolved star with a
spectroscopically derived stellar radius and mass of
$3.88^{+0.48}_{-0.42}~\mathrm{R_\odot}$ and
$1.53^{+0.13}_{-0.12}~\mathrm{M_\odot}$, respectively, and a very close-in
transiting planet, with $a/R_\star = 3.4$. Radial velocity (RV) follow-up using
the HARPS, FIES and PFS instruments leads to a planetary mass of
$50.3^{+9.7}_{-9.4}~\mathrm{M_\oplus}$. In combination with a radius
measurement of $8.3 \pm 1.1~\mathrm{R_\oplus}$, this results in a mean
planetary density of $0.50^{+0.29}_{-0.17}$ g~cm$^{-3}$. We furthermore
discover a long-term RV trend, which may be caused by a long-period planet or
stellar companion. Because K2-39b has a short orbital period, its existence
makes it seem unlikely that tidal destruction is wholly responsible for the
differences in planet populations around subgiant and main-sequence stars.
Future monitoring of the transits of this system may enable the detection of
period decay and constrain the tidal dissipation rates of subgiant stars.


title:
The use of the multi-cumulant tensor analysis for the algorithmic
  optimisation of investment portfolios

abstract:
  The cumulant analysis plays an important role in non Gaussian distributed
data analysis. The shares' prices returns are good example of such data. The
purpose of this research is to develop the cumulant based algorithm and use it
to determine eigenvectors that represent investment portfolios with low
variability. Such algorithm is based on the Alternating Least Square method and
involves the simultaneous minimisation 2'nd -- 6'th cumulants of the
multidimensional random variable (percentage shares' returns of many
companies). Then the algorithm was tested during the recent crash on the Warsaw
Stock Exchange. To determine incoming crash and provide enter and exit signal
for the investment strategy the Hurst exponent was calculated using the local
DFA. It was shown that introduced algorithm is on average better that benchmark
and other portfolio determination methods, but only within examination window
determined by low values of the Hurst exponent. Remark that the algorithm of is
based on cumulant tensors up to the 6'th order calculated for a
multidimensional random variable, what is the novel idea. It can be expected
that the algorithm would be useful in the financial data analysis on the world
wide scale as well as in the analysis of other types of non Gaussian
distributed data.


title: Electronic structure of cyanocobalamin: DFT+QMC study

abstract:
  We study the electronic structure and the magnetic correlations of
cyanocobalamin ($C_{63}H_{88}CoN_{14}O_{14}P$) by using the framework of the
multi-orbital single-impurity Haldane-Anderson model of a transition metal
impurity in a semiconductor host. Here, we first determine the parameters of
the Anderson Hamiltonian by performing density functional theory (DFT)
calculations. Then, we use the quantum Monte Carlo (QMC) technique to obtain
the electronic structure and the magnetic correlation functions for this
effective model. We find that new electronic states, which correspond to
impurity bound states, form above the lowest unoccupied level of the host
semiconductor. These new states derive from the atomic orbitals at the cobalt
site and the rest of the molecule. We observe that magnetic moments develop at
the Co($3d_{\nu}$) orbitals and over the surrounding sites. We also observe
that antiferromagnetic correlations exist between the Co($3d_{\nu}$) orbitals
and the surrounding atoms. These antiferromagnetic correlations depend on the
filling of the impurity bound states.


title: A lambda 3mm and 1mm line survey toward the yellow hypergiant IRC +10420

abstract:
  Our knowledge of the chemical properties of the circumstellar ejecta of the
most massive evolved stars is particularly poor. We aim to study the chemical
characteristics of the prototypical yellow hypergiant star, IRC +10420. For
this purpose, we obtained full line surveys at 1 and 3mm atmospheric windows.
  We have identified 106 molecular emission lines from 22 molecular species.
Approximately half of the molecules detected are N-bearing species, in
particular HCN, HNC, CN, NO, NS, PN, and N2H+. We used rotational diagrams to
derive the density and rotational temperature of the different molecular
species detected. We introduced an iterative method that allows us to take
moderate line opacities into account.
  We have found that IRC +10420 presents high abundances of the N-bearing
molecules compared with O-rich evolved stars. This result supports the presence
of a N-rich chemistry, expected for massive stars. Our analysis also suggests a
decrease of the 12C/13C ratio from \gtrsim 7 to \sim 3.7 in the last 3800
years, which can be directly related to the nitrogen enrichment observed. In
addition, we found that SiO emission presents a significant intensity decrease
for high-J lines when compared with older observations. Radiative transfer
modeling shows that this variation can be explained by a decrease in the
infrared (IR) flux of the dust. The origin of this decrease might be an
expansion of the dust shell or a lower stellar temperature due to the pulsation
of the star.


title: Census Tract License Areas: Disincentive for Sharing the 3.5GHz band?

abstract:
  Flexible licensing model is a necessary enabler of the technical and
procedural complexities of Spectrum Access System (SAS)-based sharing
framework. The purpose of this study is to explore the effectiveness of 3.5GHz
Licensing Framework - based on census tracts as area units, areas whose main
characteristic is population. As such, the boundary of census tract does not
follow the edge of wireless network coverage. We demonstrate why census tracts
are not suitable for small cell networks licensing, by (1) gathering and
analysing the official census data, (2) exploring the boundaries of census
tracts which are in the shape of nonconvex polygons and (3) giving a measure of
effectiveness of the licensing scheme through metrics of area loss and the
number of people per census tract with access to spectrum. Results show that
census tracts severely impact the effectiveness of the licensing framework
since almost entire strategically important cities in the U.S. will not avail
from spectrum use in 3.5GHz band. Our paper does not seek to challenge the core
notion of geographic licensing concept, but seeks a corrective that addresses
the way the license is issued for a certain area of operation. The effects that
inappropriate size of the license has on spectrum assignments lead to spectrum
being simply wasted in geography, time and frequency or not being assigned in a
fair manner. The corrective is necessary since the main goal of promoting
innovative sharing in 3.5 GHz band is to put spectrum to more efficient use.


title: RAFCON: a Graphical Tool for Task Programming and Mission Control

abstract:
  There are many application fields for robotic systems including service
robotics, search and rescue missions, industry and space robotics. As the
scenarios in these areas grow more and more complex, there is a high demand for
powerful tools to efficiently program heterogeneous robotic systems. Therefore,
we created RAFCON, a graphical tool to develop robotic tasks and to be used for
mission control by remotely monitoring the execution of the tasks. To define
the tasks, we use state machines which support hierarchies and concurrency.
Together with a library concept, even complex scenarios can be handled
gracefully. RAFCON supports sophisticated debugging functionality and tightly
integrates error handling and recovery mechanisms. A GUI with a powerful state
machine editor makes intuitive, visual programming and fast prototyping
possible. We demonstrated the capabilities of our tool in the SpaceBotCamp
national robotic competition, in which our mobile robot solved all exploration
and assembly challenges fully autonomously. It is therefore also a promising
tool for various RoboCup leagues.


title:
Does Multimodality Help Human and Machine for Translation and Image
  Captioning?

abstract:
  This paper presents the systems developed by LIUM and CVC for the WMT16
Multimodal Machine Translation challenge. We explored various comparative
methods, namely phrase-based systems and attentional recurrent neural networks
models trained using monomodal or multimodal data. We also performed a human
evaluation in order to estimate the usefulness of multimodal data for human
machine translation and image description generation. Our systems obtained the
best results for both tasks according to the automatic evaluation metrics BLEU
and METEOR.


title: The Fermi Paradox is Neither Fermis Nor a Paradox

abstract:
  The so-called Fermi paradox claims that if technological life existed
anywhere else, we would see evidence of its visits to Earth-and since we do
not, such life does not exist, or some special explanation is needed. Enrico
Fermi, however, never published anything on this topic. On the one occasion he
is known to have mentioned it, he asked 'where is everybody?'- apparently
suggesting that we don't see extraterrestrials on Earth because interstellar
travel may not be feasible, but not suggesting that intelligent
extraterrestrial life does not exist, or suggesting its absence is paradoxical.
  The claim 'they are not here; therefore they do not exist' was first
published by Michael Hart, claiming that interstellar travel and colonization
of the galaxy would be inevitable if intelligent extraterrestrial life existed,
and taking its absence here as proof that it does not exist anywhere. The Fermi
paradox appears to originate in Hart's argument, not Fermi's question.
  Clarifying the origin of these ideas is important, because the Fermi paradox
is seen by some as an authoritative objection to searching for evidence of
extraterrestrial intelligence-cited in the U. S. Congress as a reason for
killing NASA's SETI program on one occasion-but evidence indicates that it
misrepresents Fermi's views, misappropriates his authority, deprives the actual
authors of credit, and is not a valid paradox.
  Keywords: Astrobiology, SETI, Fermi paradox, extraterrestrial life


title: Four dual AGN candidates observed with the VLBA

abstract:
  According to hierarchical structure formation models, merging galaxies are
expected to be seen in different stages of their coalescence. However,
currently there are no straightforward observational methods neither to select
nor to confirm a large number of dual active galactic nuclei (AGN) candidates.
Most attempts involve the better understanding of double-peaked narrow emission
line sources, to distinguish the objects where the emission lines originate
from narrow-line kinematics or jet-driven outflows from those which might
harbour dual AGN. We observed four such candidate sources with the Very Long
Baseline Array (VLBA) at 1.5 GHz with $\sim$ 10 milli-arcsecond angular
resolution where spectral profiles of AGN optical emission suggested the
existence of dual AGN. In SDSS J210449.13-000919.1 and SDSS J23044.82-093345.3,
the radio structures are aligned with the optical emission features, thus the
double-peaked emission lines might be the results of jet-driven outflows. In
the third detected source SDSS J115523.74+150756.9, the radio structure is less
extended and oriented nearly perpendicular to the position angle derived from
optical spectroscopy. The fourth source remained undetected with the VLBA but
it has been imaged with the Very Large Array at arcsec resolution a few months
before our observations, suggesting the existence of extended radio structure.
In none of the four sources did we detect two radio-emitting cores, a
convincing signature of duality.


title:
Scalar products of Bethe vectors in models with $\mathfrak{gl}(2|1)$
  symmetry 1. Super-analog of Reshetikhin formula

abstract:
  We study scalar products of Bethe vectors in integrable models solvable by
nested algebraic Bethe ansatz and possessing $\mathfrak{gl}(2|1)$ symmetry.
Using explicit formulas of the monodromy matrix entries multiple actions onto
Bethe vectors we obtain a representation for the scalar product in the most
general case. This explicit representation appears to be a sum over partitions
of the Bethe parameters. It can be used for the analysis of scalar products
involving on-shell Bethe vectors.
  As a by-product, we obtain a determinant representation for the scalar
products of generic Bethe vectors in integrable models with
$\mathfrak{gl}(1|1)$ symmetry.


title:
A Polynomial Time Graph Isomorphism Algorithm For Graphs That Are Not
  Locally Triangle-Free

abstract:
  In this paper, we show the existence of a polynomial time graph isomorphism
algorithm for all graphs excluding graphs that are locally trianglefree. This
particular class of graphs allows to divide the graph into neighbourhood
sub-graph where each of induced sub-graph (neighbourhood) has at least 2
vertices. We construct all possible permutations for each induced sub-graph
using a search tree. We construct automorphisms of subgraphs based on these
permutations. Finally, we decide isomorphism through automorphisms .
  The author expects that the solution, present in this paper, may lead to a
faster algorithm for the general case of graph isomorphism (using " barycentric
subdivision" ). The paper might affect group isomorphism also as we may
construct graphs (corresponds to a particular group) in way so we can avoid it
to be a triangle free graph. Since,for a given group G , each choice of a
generating set will give a different Cayley graph.


title: Constraining light gravitino mass with 21 cm line observation

abstract:
  We investigate how well we can constrain the mass of light gravitino m_3/2 by
using future observations of 21 cm line fluctuations such as Square Kilometre
Array (SKA) and Omniscope. Models with light gravitino with the mass m_3/2 <
O(10) eV are quite interesting because they are free from the cosmological
gravitino problem and consistent with many baryogenesis/leptogenesis scenarios.
We evaluate expected constraints on the mass of light gravitino from the
observations of 21 cm line, and show that the observations are quite useful to
prove the mass. If the gravitino mass is m_3/2 = 1 eV, we found expected 1
sigma errors on m_3/2 are sigma(m_3/2) = 0.25 eV (SKA phase 1), 0.16 eV (SKA
phase 2) and 0.067 eV (Omniscope) in combination with Planck + Simons Array +
DESI (BAO) + H_0. Additionally, we also discuss detectability of the effective
number of neutrino species by varying the effective number of neutrino species
for light gravitino N_3/2 and constraints on the mass of light gravitino in the
presence of massive neutrinos. We show that 21 cm line observations can detect
the nonzero value of N_3/2, and allow us to distinguish the effects of the
light gravitino from those of massive neutrino.


title: Platonic and alternatinc 2-groups

abstract:
  We recall Schur's work on universal central extensions and develop the
analogous theory for categorical extensions of groups. We prove that the String
2-groups are universal in this sense and study in detail their restrictions to
the finite subgroups of the Spin groups. Of particular interest are subgroups
of the 3-sphere Spin(3), as well as the spin double covers of the alternating
groups, whose categorical extensions turn out to be governed by the stable
3-stem.


title: Bitcoin's Security Model Revisited

abstract:
  We revisit the fundamental question of Bitcoin's security against double
spending attacks. While previous work has bounded the probability that a
transaction is reversed, we show that no such guarantee can be effectively
given if the attacker can choose when to launch the attack. Other approaches
that bound the cost of an attack have erred in considering only limited attack
scenarios, and in fact it is easy to show that attacks may not cost the
attacker at all. We therefore provide a different interpretation of the results
presented in previous papers and correct them in several ways. We provide
different notions of the security of transactions that provide guarantees to
different classes of defenders: merchants who regularly receive payments,
miners, and recipients of large one-time payments. We additionally consider an
attack that can be launched against lightweight clients, and show that these
are less secure than their full node counterparts and provide the right
strategy for defenders in this case as well. Our results, overall, improve the
understanding of Bitcoin's security guarantees and provide correct bounds for
those wishing to safely accept transactions.


title: Network Resource Sharing Games with Instantaneous Reciprocity

abstract:
  We propose a generic strategic network resource sharing game between a set of
players representing operators. The players negotiate which sets of players
share given resources, serving users with varying sensitivity to interference.
We prove that the proposed game has a Nash equilibrium, to which a greedily
played game converges. Furthermore, simulation results show that, when applied
to inter-operator spectrum sharing in small-cell indoor office environment, the
convergence is fast and there is a significant performance improvement for the
operators when compared to the default resource usage configuration.


title: Thermoelectric study of dissipative quantum dot heat engines

abstract:
  This paper examines the thermoelectric response of a dissipative quantum dot
heat engine based on the Anderson-Holstein model in two relevant operating
limits: (i) when the dot phonon modes are out of equilibrium, and (ii) when the
dot phonon modes are strongly coupled to a heat bath. In the first case, a
detailed analysis of the physics related to the interplay between the quantum
dot level quantization, the on-site Coulomb interaction and the electron-phonon
coupling on the thermoelectric performance reveals that an n-type heat engine
performs better than a p-type heat engine. In the second case, with the aid of
the dot temperature estimated by incorporating a {\it{thermometer bath}}, it is
shown that the dot temperature deviates from the bath temperature as
electron-phonon interaction becomes stronger. Consequently, it is demonstrated
that the dot temperature controls the direction of phonon heat currents,
thereby influencing the thermoelectric performance. Finally, the conditions on
the maximum efficiency with varying phonon couplings between the dot and all
the other macroscopic bodies are analyzed in order to reveal the nature of the
optimum junction.


title: Forest Floor Visualizations of Random Forests

abstract:
  We propose a novel methodology, forest floor, to visualize and interpret
random forest (RF) models. RF is a popular and useful tool for non-linear
multi-variate classification and regression, which yields a good trade-off
between robustness (low variance) and adaptiveness (low bias). Direct
interpretation of a RF model is difficult, as the explicit ensemble model of
hundreds of deep trees is complex. Nonetheless, it is possible to visualize a
RF model fit by its mapping from feature space to prediction space. Hereby the
user is first presented with the overall geometrical shape of the model
structure, and when needed one can zoom in on local details. Dimensional
reduction by projection is used to visualize high dimensional shapes. The
traditional method to visualize RF model structure, partial dependence plots,
achieve this by averaging multiple parallel projections. We suggest to first
use feature contributions, a method to decompose trees by splitting features,
and then subsequently perform projections. The advantages of forest floor over
partial dependence plots is that interactions are not masked by averaging. As a
consequence, it is possible to locate interactions, which are not visualized in
a given projection. Furthermore, we introduce: a goodness-of-visualization
measure, use of colour gradients to identify interactions and an out-of-bag
cross validated variant of feature contributions.


title: Klyachko models for ladder representations

abstract:
  We give a new proof of the existence of Klyachko models for unitary
representations of ${\rm GL}_{n}(F)$ over a non-archimedean local field $F$.
Our methods are purely local and are based on studying distinction within the
class of ladder representations introduced by Lapid and Minguez. We classify
those ladder representations that are distinguished with respect to Klyachko
models. We prove the hereditary property of these models for induced
representations from arbitrary finite length representations. Finally, in the
other direction and in the context of admissible representations induced from
ladder, we study the relation between distinction of the parabolic induction
with respect to the symplectic groups and distinction of the inducing data.


title: Some inequalities for partial derivatives on time scales

abstract:
  We first prove some weighted inequalities for compositions of functions on
time scales which are in turn applied to establish some new dynamic Opial-type
inequalities in several variables. Some generalizations and applications to
partial differential dynamic equations are also considered.


title:
Identification of Sparse Continuous-Time Linear Systems with Low
  Sampling Rate: Optimization Approaches

abstract:
  This paper addresses identification of sparse linear and noise-driven
continuous-time state-space systems, i.e., the right-hand sides in the
dynamical equations depend only on a subset of the states. The key assumption
in this study, is that the sample rate is not high enough to directly infer the
continuous time system from the data. This assumption is relevant in
applications where sampling is expensive or requires human intervention (e.g.,
biomedicine applications). We propose an iterative optimization scheme with
$l_1$-regularization, where the search directions are restricted those that
decrease prediction error in each iteration. We provide numerical examples
illustrating the proposed method; the method outperforms the least squares
estimation for large noise.


title:
Some Unified Integrals Associated with Generalized Bessel-Maitland
  Function

abstract:
  Generalized integral formulas involving the generalized Bessel-Maitland
function are considered and it expressed in terms of generalized Wright
hypergeometric functions. By assuming appropriate values of the parameters in
the main results, we obtained some interesting results of ordinary Bessel
function.


title: The Radon transform and the Hough transform: a unifying perspective

abstract:
  The Radon transform is a linear integral transform that mimics the data
formation process in medical imaging modalities like X-ray Computerized
Tomography and Positron Emission Tomography. The Hough transform is a pattern
recognition technique, which is mainly used to detect straight lines in digital
images and which has been recently extended to the automatic recognition of
algebraic plane curves. Although defined in very different ways, in numerical
applications both transforms ultimately take an image as an input and provide,
as an output, a function defined on a parameter space. The parameters in this
space describe a family of curves, which represent either the integration
domains considered in the (generalized) Radon transform, or the curves to be
detected by means of the Hough transform. In both cases, the 2D plot of the
intensity values of the output function is the so-called (Radon or Hough)
sinogram. While the Hough sinogram is produced by an algorithm whose
implementation requires that the parameter space be discretized in cells, the
Radon sinogram is mathematically defined on a continuous parameter space, which
in turn may need to be discretized just for physical or numerical reasons. In
this paper, by considering a more general and n-dimensional setting, we prove
that, whether the input image is described as a set of points (possibly with
different intensity values) or as a piecewise constant function, its (rescaled)
Hough sinogram converges to the corresponding Radon sinogram as the
discretization step in the parameter space tends to zero. We also show that
this result may have a notable impact on the image reconstruction problem of
inverting the Radon sinogram recorded by a medical imaging scanner, and that
the description of the Hough transform problem within the framework of
regularization theory for inverse problems is worth investigating.


title: Floating point numbers are real numbers

abstract:
  Floating point arithmetic allows us to use a finite machine, the digital
computer, to reach conclusions about models based on continuous mathematics. In
this article we work in the other direction, that is, we present examples in
which continuous mathematics leads to sharp, simple and new results about the
evaluation of sums, square roots and dot products in floating point arithmetic.


title: Non-Tiles and Walls - A Variant on the Heesch Problem

abstract:
  The Heesch problem 'grades' polygons that fail to tile the plane in terms of
the number of layers (or corollas) of copies of it that can be formed around a
central unit. We study the different topology of ' walls', which we define to
be simply connected regions that divide the plane exactly into two simply
connected regions. We present preliminary results and conjectures.


title: Extension of Summation Formulas involving Stirling series

abstract:
  This paper presents a family of rapidly convergent summation formulas for
various finite sums of the form $\sum_{k=0}^{\lfloor x\rfloor}f(k)$, where $x$
is a positive real number.


title: On some remarkable congruences between two elliptic curves

abstract:
  We exhibit two non-isogenous rational elliptic curves with $17$-torsion
subgroups isomorphic as Galois modules.


title: On the Barr exactness property of $\mathsf{BXMod/R}$

abstract:
  In this work, it is shown that the category $\mathsf{BXMod/R}$ of braided
crossed modules over a fixed commutative algebra $R$ is an exact category in
the sense of Barr.


title:
A Note on the Construction of Complex and Quaternionic Vector Fields on
  Spheres

abstract:
  A relationship between real, complex, and quaternionic vector fields on
spheres is given by using a relationship between the corresponding standard
inner products. The number of linearly independent complex vector fields on the
standard $(4n-1)$-sphere is shown to be twice the number of linearly
independent quaternionic vector fields plus $d$, where $ d = 1 \mbox{ or } 3$.


title:
Tuning and validation of hadronic event generator for $R$ value
  measurements in the tau-charm region

abstract:
  To measure the $R$ value in an energy scan experiment with $\ee$ collisions,
precise calculation of initial state radiation is required in event generators.
We present an event generator for this consideration, which incorporates
initial state radiation effects up to the second order accuracy, and the
radiative correction factor is calculated using the totally hadronic Born cross
section. The measured exclusive processes are generated according to their
cross sections, while the unknown processes are generated using the LUND Area
Law model, and its parameters are tuned with data collected at $\sqrt s=3.65$
GeV. The optimized values are validated with data in the range $\sqrt
s=2.2324\sim3.671$ GeV. These optimized parameters are universally valid for
event generation below the $D\bar D$ threshold.


title:
Spherically symmetric solvent is sufficient to explain lower critical
  solution temperature in polymer solutions

abstract:
  We study the lower critical solution temperature (LCST) in thermoresponsive
polymer solutions by means of a coarse grained single polymer chain simulation
and a theoretical approach. The simulation model includes solvent explicitly
and thus accounts for solvent interactions and entropy directly. The
theoretical model consists of a single chain polymer in an implicit solvent
where the effect of solvent is included through the intra-polymer solvophobic
potential proposed by Kolomeisky and Widom. Our results indicate that the LCST
behavior is determined by the competition between the mean energy difference
between the bulk and bound solvent, and the entropy loss due to the bound
solvent. At low temperatures, solvent molecules are bound to the polymer and
the solvophobicity of the polymer is screened, resulting in a coiled state. At
high temperatures the entropy loss due to bound solvent offsets the energy gain
due to binding which causes the solvent molecules to unbind, leading to the
collapse of the polymer chain to a globular state. Furthermore, the coarse
grained nature of these models indicates that mean interaction energies are
sufficient to explain LCST in comparison to specific solvent structural
arrangements.


title: Geophysical flows and the effects of a strong surface tension

abstract:
  In the present note we review some recent results for a class of singular
perturbation problems for a Navier-Stokes-Korteweg system with Coriolis force.
More precisely, we study the asymptotic behaviour of solutions when taking
incompressible and fast rotation limits simultaneously, in a constant
capillarity regime. Our main purpose here is to explain in detail the
description of the phenomena we want to capture, and the mathematical
derivation of the system of equations. Hence, a huge part of this work is
devoted to physical considerations and mathematical modeling.

categories: math.AP cond-mat.quant-gas cond-mat.stat-mech physics.flu-dyn physics.geo-ph


title: Going Deeper for Multilingual Visual Sentiment Detection

abstract:
  This technical report details several improvements to the visual concept
detector banks built on images from the Multilingual Visual Sentiment Ontology
(MVSO). The detector banks are trained to detect a total of 9,918
sentiment-biased visual concepts from six major languages: English, Spanish,
Italian, French, German and Chinese. In the original MVSO release,
adjective-noun pair (ANP) detectors were trained for the six languages using an
AlexNet-styled architecture by fine-tuning from DeepSentiBank. Here, through a
more extensive set of experiments, parameter tuning, and training runs, we
detail and release higher accuracy models for detecting ANPs across six
languages from the same image pool and setting as in the original release using
a more modern architecture, GoogLeNet, providing comparable or better
performance with reduced network parameter cost.
  In addition, since the image pool in MVSO can be corrupted by user noise from
social interactions, we partitioned out a sub-corpus of MVSO images based on
tag-restricted queries for higher fidelity labels. We show that as a result of
these higher fidelity labels, higher performing AlexNet-styled ANP detectors
can be trained using the tag-restricted image subset as compared to the models
in full corpus. We release all these newly trained models for public research
use along with the list of tag-restricted images from the MVSO dataset.


title: On equicontinuity of inverse mappings in a closure of a domain

abstract:
  For some class of mappings satisfying upper modular estimates with respect to
families of curves, a behavior of the corresponding inverse mappings is
investigated. In the terms of prime ends, it is proved that, families of such
homeomorphisms are equicontinuous (normal) in the closure of a given domain.


title: Twelve new primitive binary trinomials

abstract:
  We exhibit twelve new primitive trinomials over GF(2) of record degrees
$42643801$, $43112609$, and $74207281$. In addition we report the first
Mersenne exponent not ruled out by Swan's theorem - namely $57885161$ - for
which no primitive trinomial exists. This completes the search for the
currently known Mersenne prime exponents.


title:
The Chiral Anomaly, Dirac and Weyl Semimetals, and Force-Free Magnetic
  Fields

abstract:
  The chiral anomaly is a purely quantum mechanical phenomenon that has a long
history dating back to the late 1960s. Surprisingly, it has recently made a
macroscopic appearance in condensed matter physics. A brief introduction to the
relevant features of this anomaly is given and it is shown that its appearance
in condensed matter systems must involve force-free magnetic fields, which may
help explain the long current relaxation times in Dirac and Weyl semimetals.


title:
A New Gravitational-Wave Signature from Standing Accretion Shock
  Instabilities in Supernovae

abstract:
  We present results from fully relativistic three-dimensional core-collapse
supernova (CCSN) simulations of a non-rotating 15 Msun star using three
different nuclear equations of state (EoSs). From our simulations covering up
to ~350 ms after bounce, we show that the development of the standing accretion
shock instability (SASI) differs significantly depending on the stiffness of
nuclear EoS. Generally, the SASI activity occurs more vigorously in models with
softer EoS. By evaluating the gravitational-wave (GW) emission, we find a new
GW signature on top of the previously identified one, in which the typical GW
frequency increases with time due to an accumulating accretion to the
proto-neutron star (PNS). The newly observed quasi-periodic signal appears in
the frequency range from ~100 to 200 Hz and persists for ~150 ms before
neutrino-driven convection dominates over the SASI. By analyzing the cycle
frequency of the SASI sloshing and spiral modes as well as the mass accretion
rate to the emission region, we show that the SASI frequency is correlated with
the GW frequency. This is because the SASI-induced temporary perturbed mass
accretion strike the PNS surface, leading to the quasi-periodic GW emission.
Our results show that the GW signal, which could be a smoking-gun signature of
the SASI, is within the detection limits of LIGO, advanced Virgo, and KAGRA for
Galactic events.


title:
Non-split Brauer-Severi varieties do not admit full exceptional
  collections

abstract:
  Recently, Novakovi\'c conjectured that non-split Brauer-Severi varieties do
not admit full strong exceptional collections. In this short note, we explain
how a stronger version of this conjecture follows easily from known results on
noncommutative motives.


title:
Elementary construction of residue currents associated to Cohen-Macaulay
  ideals

abstract:
  For a Cohen-Macaulay ideal of holomorphic functions, we construct by
elementary means residue currents whose annihilator is precisely the given
ideal. We give two proofs that the currents have the prescribed annihilator,
one using the theory of linkage, and another using an explicit division formula
involving these residue currents to express the ideal membership.