title: Validated Computation of Heteroclinic Sets

abstract:
  In this work we develop a method for computing mathematically rigorous
enclosures of some one dimensional manifolds of heteroclinic orbits for
nonlinear maps. Our method exploits a rigorous curve following argument build
on high order Taylor approximation of the local stable/unstable manifolds. The
curve following argument is a uniform interval Newton method applied on short
line segments. The definition of the heteroclinic sets involve compositions of
the map and we use a Lohner-type representation to overcome the accumulation of
roundoff errors. Our argument requires precise control over the local unstable
and stable manifolds so that we must first obtain validated a-posteriori error
bounds on the truncation errors associated with the manifold approximations. We
illustrate the utility of our method by proving some computer assisted theorems
about heteroclinic invariant sets for a volume preserving map of
$\mathbb{R}^3$.


title: Receptor arrays optimized for natural odor statistics

abstract:
  Natural odors typically consist of many molecules at different
concentrations. It is unclear how the numerous odorant molecules and their
possible mixtures are discriminated by relatively few olfactory receptors.
Using an information-theoretic model, we show that a receptor array is optimal
for this task if it achieves two possibly conflicting goals: (i) each receptor
should respond to half of all odors and (ii) the response of different
receptors should be uncorrelated when averaged over odors presented with
natural statistics. We use these design principles to predict statistics of the
affinities between receptors and odorant molecules for a broad class of odor
statistics. We also show that optimal receptor arrays can be tuned to either
resolve concentrations well or distinguish mixtures reliably. Finally, we use
our results to predict properties of experimentally measured receptor arrays.
Our work can thus be used to better understand natural olfaction and it also
suggests ways to improve artificial sensor arrays.


title: Feedback Control of Waiting Times

abstract:
  Feedback loops are known as a versatile tool for controlling transport in
small systems, which usually have large intrinsic fluctuations. Here we
investigate the control of a temporal correlation function, the waiting time
distribution, under active and passive feedback conditions. We develop a
general formalism and then specify to the simple unidirectional transport
model, where we compare costs of open loop and feedback control and use methods
from optimal control theory to optimize waiting time distributions.


title:
On the mixed Hodge structures of the intersection cohomology stalks of
  complex hypersurfaces

abstract:
  We consider a hypersurface in $\mathbb{C}^n$ with an isolated singular point
at the origin, and study the mixed Hodge structure of the stalk of its
intersection cohomology complex at the origin. In particular we express the
dimension of each graded piece of the weight filtration of this mixed Hodge
structure in terms of the numbers of the Jordan blocks in the Milnor monodromy.


title: Models of interacting supernovae and their spectral diversity

abstract:
  Using radiation-hydrodynamics and radiative-transfer simulations, we explore
the origin of the spectral diversity of interacting supernovae (SNe) of type
IIn. We revisit SN1994W and investigate the dynamical configurations that can
give rise to spectra with narrow lines at all times. We find that a standard
~10Msun 10^51erg SN ejecta ramming into a 0.4Msun dense CSM is inadequate for
SN1994W, as it leads to the appearance of broad lines at late times. This
structure, however, generates spectra that exhibit the key morphological
changes seen in SN1998S. For SN1994W, we consider a completely different
configuration, which involves the interaction at a large radius of a low mass
inner shell with a high mass outer shell. Such a structure may arise in an
8-12Msun star from a nuclear flash (e.g., of Ne) followed within a few years by
core collapse. Our simulations show that the large mass of the outer shell
leads to the complete braking of the inner shell material, the formation of a
slow dense shell, and the powering of a luminous SN IIn, even for a low inner
shell energy. Early on, our model line profiles are typical of SNe IIn,
exhibiting narrow cores and broad electron-scattering wings. As observed in
SN1994W, they also remain narrow at late times. Our SN1994W model invokes two
low energy ejections, both atypical of observed massive stars, and illustrates
the diversity of configurations leading to SNe IIn. These results also
highlight the importance of spectra to constrain the dynamical properties and
understand the origin of SNe IIn.


title:
Structural and magnetic properties of the 5$d^2$ double perovskites
  Sr$_2 B$ReO$_6$ ($B$ $=$ Y, In)

abstract:
  We have performed magnetic susceptibility, heat capacity, neutron powder
diffraction, and muon spin relaxation experiments to investigate the magnetic
ground states of the 5$d^2$ double perovskites Sr$_2$YReO$_6$ and
Sr$_2$InReO$_6$. We find that Sr$_2$YReO$_6$ is a spin glass, while
Sr$_2$InReO$_6$ hosts a non-magnetic singlet state. By making detailed
comparisons with other 5$d^2$ double perovskites, we argue that a delicate
interplay between spin-orbit coupling, non-cubic crystal fields, and exchange
interactions plays a key role in the great variation of magnetic ground states
observed for this family of materials.


title:
Quantum Monte Carlo Study of Long-Range Transverse-Field Ising Models on
  the Triangular Lattice

abstract:
  Motivated by recent experiments with a Penning ion trap quantum simulator, we
perform numerically exact Stochastic Series Expansion quantum Monte Carlo
simulations of long-range transverse-field Ising models on a triangular lattice
for different decay powers $\alpha$ of the interactions. The phase boundary for
the ferromagnet is obtained as a function of $\alpha$. For antiferromagnetic
interactions, there is strong indication that the transverse field stabilizes a
clock ordered phase with sublattice magnetization $(M,-\frac{M}{2},
-\frac{M}{2})$ with unsaturated $M < 1$ in a process known as "order by
disorder" similar to the nearest neighbour antiferromagnet on the triangular
lattice. Connecting the known limiting cases of nearest neighbour and
infinite-range interactions, a semiquantitative phase diagram is obtained.
Magnetization curves for the ferromagnet for experimentally relevant system
sizes and with open boundary conditions are presented.


title: Information theory demonstration of the Richardson cascade

abstract:
  Turbulence theory is usually concerned with the statistical moments of the
velocity or its fluctuations. One could also analyze the implicit probability
distributions. This is the purview of information theory. Here we use
information theory, specifically the conditional entropy, to analyze (quasi-)2D
turbulence. We recast Richardson's "eddy hypothesis" that large eddies break up
into small eddies in time in the language of information theory. In addition to
confirming Richardson's idea, we find that self-similarity and turbulent length
scales reappear naturally. Not surprisingly, we also find that the direction of
information transfer is the same as the direction of the cascade itself.
Consequently, intermittency may be considered a necessary companion to all
turbulent flows.


title:
Barrier effect of grain boundaries on the avalanche propagation of
  polycrystalline plasticity

abstract:
  To investigate the barrier effect of grain boundaries on the propagation of
avalanche-like plasticity at the atomic-scale, we perform three-dimensional
molecular dynamics simulations by using simplified polycrystal models including
symmetric-tilt grain boundaries. The cut-offs of stress-drop distributions
following power-law distributions decrease as the size of the crystal grains
decreases. We show that some deformation avalanches are confined by grain
boundaries; on the other hand, unignorable avalanches penetrate all the grain
boundaries included in the models. The blocking probability that one grain
boundary hinders this system-spanning avalanche is evaluated by using an
elemental probabilistic model.


title:
Variable Transmission Voltage for Loss Minimization in Long Offshore
  Wind Farm AC Export Cables

abstract:
  Connection of offshore wind farms to shore requires the use of submarine
cables. In the case of long HVAC connections, the capacitive charging currents
limit the transfer capability and lead to high losses. This paper shows that
the losses can be substantially reduced by continuously adjusting the cable
operating voltage according to the instantaneous wind farm power
production.Calculations for a 320 MW windfarm connected to shore via a 200 km
cable at 220 kV nominal voltage shows that an annual loss reduction of 9
percent is achievable by simply using a 15 percent tap changer voltage
regulation on the two transformers. Allowing a larger voltage regulation range
leads to further loss reduction (13 percent for 0.4-1.0 p.u. voltage range). If
the windfarm has a low utilization factor, the loss reduction potential is
demonstrated to be as high as 21 percent . The methodology can be applied
without introducing new technology that needs to be developed or qualified.


title: Performance study of single undoped CsI crystals for the Mu2e experiment

abstract:
  The Mu2e experiment at Fermilab aims to measure the charged lepton flavor
violating neutrinoless muon to electron conversion. The goal of the experiment
is to reach a single event sensitivity of 2.5 x 10^{-17}, to set an upper limit
on the muon conversion rate at 6.7 x 10^{-17} in a three years run. For this
purpose, the Mu2e detector is designed to identify electrons from muon
conversion and reduce the background to a negligible level. It consists of a
low mass straw tracker and a pure CsI crystal calorimeter.
  In this paper, the performance of undoped CsI single crystal is reported.
Crystals from many vendors have been characterized by determining their Light
Yield (LY) and Longitudinal Response Uniformity (LRU), when read with a UV
extended PMT, and their time resolution when coupled to a Silicon
Photomultiplier. The crystals show a LY of ~ 100 photoelectrons per MeV when
wrapped with Tyvek and coupled to the PMT without optical grease. The LRU is
well represented by a linear slope that is on average 0.6%/cm. Both
measurements have been performed using a 22Na source. The timing performance
have been evaluated exploiting minimum ionizing particles, with MPPC readout. A
timing resolution better than 400 ps is achieved (at ~20MeV).


title:
A Mahler-type estimate of weighted Fekete sums on the Berkovich
  projective line

abstract:
  We establish a Mahler-type estimate of weighted Fekete sums on the Berkovich
projective line over an algebraically closed field of possibly positive
characteristic that is complete with respect to a non-trivial and possibly
non-archimedean absolute value.


title:
Unipolar magnetic field pulses as transient signals prior to the 2009
  Aquila earthquake shock

abstract:
  Unipolar pre-seismic magnetic field pulses have been observed first by Bleier
et al. (2009) and Villante et al. (2010) and Nenovski et al. (2013). In the
present study a detailed analysis of the pulses is conducted looking for
signatures of transient signals similar to that recorded at the 2009 Aquila
earthquake main shock (Nenovski, 2015). Various magnetic field data around the
Aquila earthquake provide an instrumental basis for such an analysis. In
addition to fluxgate magnetometer data (already examined in previous studies),
overhauser magnetometer data are involved. The result is a detection and
discrimination of transient signals of diffusive form that appear prior to the
earthquake main shock.


title:
Spectral Statistics for one dimensional Anderson model with unbounded
  but decaying potential

abstract:
  In this work, we study the spectral statistics for Anderson model on
$\ell^2(\mathbb{N})$ with decaying randomness whose single site distribution
has unbounded support. Here we consider the operator $H^\omega$ given by
$(H^\omega u)_n=u_{n+1}+u_{n-1}+a_n\omega_n u_n$, $a_n\sim n^{-\alpha}$ and
$\{\omega_n\}$ are real i.i.d random variables following symmetric distribution
$\mu$ with fat tail, i.e $\mu((-R,R)^c)<\frac{C}{R^\delta}$ for $R\gg 1$, for
some constant $C$. In case of $\alpha-\frac{1}{\delta}>\frac{1}{2}$, we are
able to show that the eigenvalue process in $(-2,2)$ is the clock process.


title: Any Finite Group is the Group of Some Binary, Convex Polytope

abstract:
  For any given finite group, Schulte and Williams (2015) establish the
existence of a convex polytope whose combinatorial automorphisms form a group
isomorphic to the given group. We provide here a shorter proof for a stronger
result: the convex polytope we build for the given finite group is binary, and
even combinatorial in the sense of Naddef and Pulleyblank (1981); the diameter
of its skeleton is at most 2; any combinatorial automorphism of the polytope is
induced by some isometry of the space; any automorphism of the skeleton is a
combinatorial automorphism.


title:
Influence of X-ray radiation on the hot star wind ionization state and
  on the radiative force

abstract:
  Hot stars emit large amounts of X-rays, which are assumed to originate in the
supersonic stellar wind. Part of the emitted X-rays is subsequently absorbed in
the wind and influences its ionization state. Because hot star winds are driven
radiatively, the modified ionization equilibrium affects the radiative force.
We review the recent progress in modelling the influence of X-rays on the
radiative equilibrium and on the radiative force. We focus particularly on
single stars with X-rays produced in wind shocks and on binaries with massive
components, which belong to the most luminous objects in X-rays.


title:
Non reduced plane curve singularities with $b_1(F)=0$ and Bobadilla's
  question

abstract:
  If the first Betti number of the Milnor fibre of a plane curve singularity is
zero, then the defining function is equivalent to $x^r$.


title: Self-organized control for musculoskeletal robots

abstract:
  With the accelerated development of robot technologies, optimal control
becomes one of the central themes of research. In traditional approaches, the
controller, by its internal functionality, finds appropriate actions on the
basis of the history of sensor values, guided by the goals, intentions,
objectives, learning schemes, and so on planted into it. The idea is that the
controller controls the world---the body plus its environment---as reliably as
possible. However, in elastically actuated robots this approach faces severe
difficulties. This paper advocates for a new paradigm of self-organized
control. The paper presents a solution with a controller that is devoid of any
functionalities of its own, given by a fixed, explicit and context-free
function of the recent history of the sensor values. When applying this
controller to a muscle-tendon driven arm-shoulder system from the Myorobotics
toolkit, we observe a vast variety of self-organized behavior patterns: when
left alone, the arm realizes pseudo-random sequences of different poses but one
can also manipulate the system into definite motion patterns. But most
interestingly, after attaching an object, the controller gets in a functional
resonance with the object's internal dynamics: when given a half-filled bottle,
the system spontaneously starts shaking the bottle so that maximum response
from the dynamics of the water is being generated. After attaching a pendulum
to the arm, the controller drives the pendulum into a circular mode. In this
way, the robot discovers dynamical affordances of objects its body is
interacting with. We also discuss perspectives for using this controller
paradigm for intention driven behavior generation.


title:
A local constant factor approximation for the minimum dominating set
  problem on bounded genus graphs

abstract:
  The Minimum Dominating Set (MDS) problem is not only one of the most
fundamental problems in distributed computing, it is also one of the most
challenging ones. While it is well-known that minimum dominating sets cannot be
approximated locally on general graphs, over the last years, several
breakthroughs have been made on computing local approximations on sparse
graphs.
  This paper presents a deterministic and local constant factor approximation
for minimum dominating sets on bounded genus graphs, a very large family of
sparse graphs. Our main technical contribution is a new analysis of a slightly
modified, first-order definable variant of an existing algorithm by Lenzen et
al. Interestingly, unlike existing proofs for planar graphs, our analysis does
not rely on any topological arguments. We believe that our techniques can be
useful for the study of local problems on sparse graphs beyond the scope of
this paper.


title:
Detection and Quantification of Flow Consistency in Business Process
  Models

abstract:
  Business process models abstract complex business processes by representing
them as graphical models. Their layout, solely determined by the modeler,
affects their understandability. To support the construction of understandable
models it would be beneficial to systematically study this effect. However,
this requires a basic set of measurable key visual features, depicting the
layout properties that are meaningful to the human user. The aim of this
research is thus twofold. First, to empirically identify key visual features of
business process models which are perceived as meaningful to the user. Second,
to show how such features can be quantified into computational metrics, which
are applicable to business process models. We focus on one particular feature,
consistency of flow direction, and show the challenges that arise when
transforming it into a precise metric. We propose three different metrics
addressing these challenges, each following a different view of flow
consistency. We then report the results of an empirical evaluation, which
indicates which metric is more effective in predicting the human perception of
this feature. Moreover, two other automatic evaluations describing the
performance and the computational capabilities of our metrics are reported as
well.


title: Ralph Henstock's Lectures on the Theory of Integration

abstract:
  These are the class notes of lectures given by Ralph Henstock at the New
University of Ulster in 1970-71. The notes deal with the Riemann-complete
integral (also known as the generalized Riemann integral, the gauge integral,
and the Henstock-Kurzweil integral). They also introduce Henstock's abstract
theory of integration.


title: On a question of Zadrozny

abstract: We answer a question of Zadrozny.


title: Segmental Spatiotemporal CNNs for Fine-grained Action Segmentation

abstract:
  Joint segmentation and classification of fine-grained actions is important
for applications of human-robot interaction, video surveillance, and human
skill evaluation. However, despite substantial recent progress in large-scale
action classification, the performance of state-of-the-art fine-grained action
recognition approaches remains low. We propose a model for action segmentation
which combines low-level spatiotemporal features with a high-level segmental
classifier. Our spatiotemporal CNN is comprised of a spatial component that
uses convolutional filters to capture information about objects and their
relationships, and a temporal component that uses large 1D convolutional
filters to capture information about how object relationships change across
time. These features are used in tandem with a semi-Markov model that models
transitions from one action to another. We introduce an efficient constrained
segmental inference algorithm for this model that is orders of magnitude faster
than the current approach. We highlight the effectiveness of our Segmental
Spatiotemporal CNN on cooking and surgical action datasets for which we observe
substantially improved performance relative to recent baseline methods.


title: Stability of test ideals of divisors with small multiplicity

abstract:
  Let $(X, \Delta)$ be a log pair in characteristic $p>0$ and $P$ be a (not
necessarily closed) point of $X$. We show that there exists a constant
$\delta>0$ such that $\tau(X, \Delta)_P= \tau(X, \Delta + D)_P$ for each
effective $\mathbb{Q}$-Cartier divisor $D$ with $\mathrm{mult}_P(D) <\delta$.
As its application, we show that if $D$ is an $\mathbb{R}$-Cartier divisor on a
strongly $F$-regular projective variety, then the non-nef locus of $D$
coincides with the restricted base locus of $D$. This is a generalization of a
result of Musta\c{t}\v{a} to the singular case and can be viewed as a
characteristic $p$ analogue of a result of Cacciola--Di Biagio.


title:
Drell-Yan as an avenue to test noncommutative Standard Model at the
  Large Hadron Collider

abstract:
  We study the Drell-Yan process at the Large Hadron Collider in presence of
the noncommutative extension of standard model. Using the Seiberg-Witten map,
we calculate the production cross-section to the first order in the
noncommutative parameter $\Theta_{\mu\nu}$. Although this idea is evolving for
long, limited amount of phenomenological analysis was done so far and
dominantly in the context of linear collider. Some outstanding feature from
this non-minimal noncommutative standard model not only modify the couplings
over SM production channel, also allow additional nonstandard vertices which
can play a significant role. Hence in the Drell-Yan process, as studied in
present analysis, one also needs to account for gluon fusion process at the
tree level. Some of the characteristic signatures such as oscillatory azimuthal
distributions are outcome of the momentum dependent effective couplings. We
explore the noncommutative scale $\Lambda_{NC} \ge 0.4~\rm{TeV}$ considering
different machine energy ranging from $7~\rm{TeV}$ to $13~\rm{TeV}$.


title: On the Morita Frobenius numbers of blocks of finite reductive groups

abstract:
  We show that the Morita Frobenius number of the blocks of the alternating
groups, the finite groups of Lie type in describing characteristic, and the Ree
and Suzuki groups is 1. We also show that the Morita Frobenius number of almost
all of the unipotent blocks of the finite groups of Lie type in non-defining
characteristic is 1, and that in the remaining cases it is at most 2.


title: Face Recognition: Perspectives from the Real-World

abstract:
  In this paper, we analyze some of our real-world deployment of face
recognition (FR) systems for various applications and discuss the gaps between
expectations of the user and what the system can deliver. We evaluate some of
our proposed algorithms with ad-hoc modifications for applications such as FR
on wearable devices (like Google Glass), monitoring of elderly people in senior
citizens centers, FR of children in child care centers and face matching
between a scanned IC/passport face image and a few live webcam images for
automatic hotel/resort checkouts. We describe each of these applications, the
challenges involved and proposed solutions. Since FR is intuitive in nature and
we human beings use it for interactions with the outside world, people have
high expectations of its performance in real-world scenarios. However, we
analyze and discuss here that it is not the case, machine recognition of faces
for each of these applications poses unique challenges and demands specific
research components so as to adapt in the actual sites.


title:
Thermodynamic Products for Einstein-Gauss-Bonnet Black Hole with
  {\alpha}-Corrected Entropy Term

abstract:
  In the present work, we consider a charged black hole in five dimensional
Einstein-Gauss-Bonnet gravity where the {\alpha} corrected entropy term is
considered. We examine the horizon radii product, entropy product, Hawking
temperature product and free energy product for both event horizon and Cauchy
horizon. Our motive is to check whether the same quantity for event horizon and
Cauchy horizon is free of mass, i.e., global or not. We further study the
stability of such black hole by computing the specific heat and free energy for
both the horizons. All these calculation might be helpful to understand the
microscopic nature of such black holes.


title:
A Convolutional Attention Network for Extreme Summarization of Source
  Code

abstract:
  Attention mechanisms in neural networks have proved useful for problems in
which the input and output do not have fixed dimension. Often there exist
features that are locally translation invariant and would be valuable for
directing the model's attention, but previous attentional architectures are not
constructed to learn such features specifically. We introduce an attentional
neural network that employs convolution on the input tokens to detect local
time-invariant and long-range topical attention features in a context-dependent
way. We apply this architecture to the problem of extreme summarization of
source code snippets into short, descriptive function name-like summaries.
Using those features, the model sequentially generates a summary by
marginalizing over two attention mechanisms: one that predicts the next summary
token based on the attention weights of the input tokens and another that is
able to copy a code token as-is directly into the summary. We demonstrate our
convolutional attention neural network's performance on 10 popular Java
projects showing that it achieves better performance compared to previous
attentional mechanisms.


title: Uniqueness of limit flow for a class of quasi-linear parabolic equations

abstract:
  We investigate the issue of uniqueness of the limit flow for a relevant class
of quasi-linear parabolic equations defined on the whole space. More precisely,
we shall investigate conditions which guarantee that the global solutions decay
at infinity uniformly in time and their entire trajectory approaches a single
steady state as time goes to infinity. Finally, we obtain a characterization of
solutions which blow-up, vanish or converge to a stationary state for initial
data of the form $\lambda \varphi_0$ while $\lambda>0$ crosses a bifurcation
value $\lambda_0$.


title: Why three generations?

abstract:
  We discuss an anthropic explanation of why there exist three generations of
fermions. If one assumes that the right-handed neutrino sector is responsible
for both the matter-antimatter asymmetry and the dark matter, then anthropic
selection favors three or more families of fermions. For successful
leptogenesis, at least two right-handed neutrinos are needed, while the third
right-handed neutrino is invoked to play the role of dark matter. The number of
the right-handed neutrinos is tied to the number of generations by the anomaly
constraints of the $U(1)_{B-L}$ gauge symmetry. Combining anthropic arguments
with observational constraints, we obtain predictions for the $X$-ray
observations, as well as for neutrinoless double-beta decay.


title: Scaling and universality in glass transition

abstract:
  Kinetic facilitated models and the Mode Coupling Theory (MCT) model B are
within those systems known to exhibit a discontinuous dynamical transition with
a two step relaxation. We consider a general scaling approach, within mean
field theory, for such systems by considering the behavior of the density
correlator <q(t)> and the dynamical susceptibility <q^2(t)> -<q(t)>^2. Focusing
on the Fredrickson and Andersen (FA) facilitated spin model on the Bethe
lattice, we extend a cluster approach that was previously developed for
continuous glass transitions by Arenzon et al (Phys. Rev. E 90, 020301(R)
(2014)) to describe the decay to the plateau, and consider a damage spreading
mechanism to describe the departure from the plateau. We predict scaling laws,
which relate dynamical exponents to the static exponents of mean field
bootstrap percolation. The dynamical behavior and the scaling laws for both
density correlator and dynamical susceptibility coincide with those predicted
by MCT. These results explain the origin of scaling laws and the universal
behavior associated with the glass transition in mean field, which is
characterized by the divergence of the static length of the bootstrap
percolation model with an upper critical dimension d_c=8.


title:
A Geometric-Probabilistic problem about the lengths of the segments
  intersected in straights that randomly cut a triangle

abstract:
  If a line cuts randomly two sides of a triangle, the length of the segment
determined by the points of intersection is also random. The object of this
study, applied to a particular case, is to calculate the probability that the
length of such segment is greater than a certain value.


title: Elements of Linear Algebra. Lecture Notes

abstract:
  These pedagogical lecture notes address to the students in theoretical
physics for helping them to understand the mechanisms of the linear operators
defined on finite-dimensional vector spaces equipped with definite or
indefinite inner products. The importance of the Dirac conjugation is pointed
out presenting its general theory and a version of the Riesz theorem for the
indefinite inner product spaces, based on the Dirac-Riesz map that combines the
action of the Riesz map with that of the metric operator. The matrix
representations of the linear operators on vector spaces with definite or
indefinite inner products is also presented.


title:
Thermodynamics, Phase Transition and Quasinormal modes with Weyl
  corrections

abstract:
  We study charged black holes in D dimensional AdS space, in the presence of
four derivative Weyl correction. We obtain the black hole solution
perturbatively up to first as well as second order in the Weyl coupling, and
show that first law of black hole thermodynamics is satisfied in all
dimensions. We study its thermodynamic phase transition and then calculate the
quasinormal frequencies of the massless scalar field perturbation. We find
that, here too, the quasinormal frequencies capture the essence of black hole
phase transition. Few subtleties near the second order critical point are
discussed.


title:
Mapping Correlations of Psychological and Connectomical Properties of
  the Dataset of the Human Connectome Project with the Maximum Spanning Tree
  Method

abstract:
  We analyzed correlations between more than 700 psychological-, anatomical-
and connectome--properties, originated from the Human Connectome Project's
(HCP) 500-subject dataset. Apart from numerous natural correlations, which
describe parameters computable or approximable from one another, we have
discovered numerous significant correlations in the dataset, never described
before. We also have found correlations described very recently independently
from the HCP-dataset: e.g., between gambling behavior and the number of the
connections leaving the insula.


title: Intersection Homology. General perversities and topological invariance

abstract:
  Topological invariance of the intersection homology of a pseudomanifold
without codimension one strata, proven by Goresky and MacPherson, is one of the
main features of this homology. This property is true for codimension-dependent
perversities with some growth conditions, verifying $\overline p(1)=\overline
p(2)=0$. King reproves this invariance by associating an intrinsic
pseudomanifold $X^*$ to any pseudomanifold $X$. His proof consists of an
isomorphism between the associated intersection homologies
$H^{\overline{p}}_{*}(X) \cong H^{\overline{p}}_{*}( X^*)$ for any perversity
$\overline{p}$ with the same growth conditions verifying $\overline p(1)\geq
0$.
  In this work, we prove a certain topological invariance within the framework
of strata-dependent perversities, $\overline{p}$, which corresponds to the
classical topological invariance if $\overline{p}$ is a GM-perversity. We also
extend it to the tame intersection homology, a variation of the intersection
homology, particularly suited for ``large'' perversities, if there is no
singular strata on $X$ becoming regular in $X^*$. In particular, under the
above conditions, the intersection homology and the tame intersection homology
are invariant under a refinement of the stratification.


title:
A correct selection of asteroid families and confirmation of a
  nongravitational effect action

abstract:
  The distribution of asteroid sizes by semimajor axes and the distribution of
the number of asteroids by albedo values for separate families are used to
selection the asteroid families more clearly. An analysis of the families
identified by Masiero et al. (2013) was carried out with the use of the
distributions of D(a) and N(p), there were defined correctly and incorrectly
selected families. A decreasing of the mean albedo with semi-major axis
increasing take place almost for all correctly selected families and which are
not truncated by resonances. The decrease is statistically significant for the
majority of these families. There is none family at a significant increase of
albedo. This confirms our previous conclusion on existence of a
non-gravitational effect in the asteroid belt which causes the spatial
separation of asteroids with different albedos.


title: Unravelling the trading invariance hypothesis

abstract:
  We confirm and substantially extend the recent empirical result of Andersen
et al. \cite{Andersen2015}, where it is shown that the amount of risk $W$
exchanged in the E-mini S\&P futures market (i.e. price times volume times
volatility) scales like the 3/2 power of the number of trades $N$. We show that
this 3/2-law holds very precisely across 12 futures contracts and 300 single US
stocks, and across a wide range of time scales. However, we find that the
"trading invariant" $I=W/N^{3/2}$ proposed by Kyle and Obizhaeva is in fact
quite different for different contracts, in particular between futures and
single stocks. Our analysis suggests $I/{\cal C}$ as a more natural candidate,
where $\cal C$ is the average spread cost of a trade, defined as the average of
the trade size times the bid-ask spread. We also establish two more complex
scaling laws for the volatility $\sigma$ and the traded volume $V$ as a
function of $N$, that reveal the existence of a characteristic number of trades
$N_0$ above which the expected behaviour $\sigma \sim \sqrt{N}$ and $V \sim N$
hold, but below which strong deviations appear, induced by the size of
the~tick.


title:
EndoNet: A Deep Architecture for Recognition Tasks on Laparoscopic
  Videos

abstract:
  Surgical workflow recognition has numerous potential medical applications,
such as the automatic indexing of surgical video databases and the optimization
of real-time operating room scheduling, among others. As a result, phase
recognition has been studied in the context of several kinds of surgeries, such
as cataract, neurological, and laparoscopic surgeries. In the literature, two
types of features are typically used to perform this task: visual features and
tool usage signals. However, the visual features used are mostly handcrafted.
Furthermore, the tool usage signals are usually collected via a manual
annotation process or by using additional equipment. In this paper, we propose
a novel method for phase recognition that uses a convolutional neural network
(CNN) to automatically learn features from cholecystectomy videos and that
relies uniquely on visual information. In previous studies, it has been shown
that the tool signals can provide valuable information in performing the phase
recognition task. Thus, we present a novel CNN architecture, called EndoNet,
that is designed to carry out the phase recognition and tool presence detection
tasks in a multi-task manner. To the best of our knowledge, this is the first
work proposing to use a CNN for multiple recognition tasks on laparoscopic
videos. Extensive experimental comparisons to other methods show that EndoNet
yields state-of-the-art results for both tasks.


title: Tryon's conjecture and Energy and momentum of Bianchi Type Universes

abstract:
  The energy and momentum of the Bianchi type $III$ universes are obtained
using different prescriptions for the energy-momentum complexes in the
framework of General Relativity. The energy and momentum of the Bianchi $III$
universe is found to be zero for the M\o{}ller prescription. For all other
prescriptions the energy and momentum vanish when the metric parameter $h$
vanishes. In an earlier work, Tripathy et al. \cite{SKT15} have obtained the
energy and momentum of Bianchi $VI_h$ metric and found that the energy of the
Universe vanish only for $h=-1$. This result raised a question: why this
specific choice?. We explored the Tryon's conjecture that 'the Universe must
have a zero net value for all conserved quantities' to get some ideas on the
specific values of this parameter for Bianchi type Universes.


title: Herding as a Learning System with Edge-of-Chaos Dynamics

abstract:
  Herding defines a deterministic dynamical system at the edge of chaos. It
generates a sequence of model states and parameters by alternating parameter
perturbations with state maximizations, where the sequence of states can be
interpreted as "samples" from an associated MRF model. Herding differs from
maximum likelihood estimation in that the sequence of parameters does not
converge to a fixed point and differs from an MCMC posterior sampling approach
in that the sequence of states is generated deterministically. Herding may be
interpreted as a"perturb and map" method where the parameter perturbations are
generated using a deterministic nonlinear dynamical system rather than randomly
from a Gumbel distribution. This chapter studies the distinct statistical
characteristics of the herding algorithm and shows that the fast convergence
rate of the controlled moments may be attributed to edge of chaos dynamics. The
herding algorithm can also be generalized to models with latent variables and
to a discriminative learning setting. The perceptron cycling theorem ensures
that the fast moment matching property is preserved in the more general
framework.


title:
Scrape-off layer ion temperature measurements at the divertor target
  during type III and type I ELMs in MAST measured by RFEA

abstract:
  In future nuclear fusion reactors high heat load events, such as
edge-localised modes (ELMs), can potentially damage divertor materials and
release impurities into the main plasma, limiting plasma performance. The most
difficult to handle are type I ELMs since they carry the largest fraction of
energy from the plasma and therefore deposit the largest heat flux at the
target and on first wall materials. Knowing the temperature of the ions
released from ELM events is important since it determines the potential
sputtering they would cause from plasma facing materials. To make measurements
of Ti by retarding field energy analyser (RFEA) during type I ELMs a new
operational technique has been used to allow faster measurements to be made;
this is called the fast swept technique (FST).


title:
FPGA Hardware Acceleration of Monte Carlo Simulations for the Ising
  Model

abstract:
  A two-dimensional Ising model with nearest-neighbors ferromagnetic
interactions is implemented in a Field Programmable Gate Array (FPGA)
board.Extensive Monte Carlo simulations were carried out using an efficient
hardware representation of individual spins and a combined global-local LFSR
random number generator. Consistent results regarding the descriptive
properties of magnetic systems, like energy, magnetization and susceptibility
are obtained while a speed-up factor of approximately 6 times is achieved in
comparison to previous FPGA-based published works and almost $10^4$ times in
comparison to a standard CPU simulation. A detailed description of the logic
design used is given together with a careful analysis of the quality of the
random number generator used. The obtained results confirm the potential of
FPGAs for analyzing the statistical mechanics of magnetic systems.


title:
Anatomy of the AGN in NGC 5548: VII. Swift study of obscuration and
  broadband continuum variability

abstract:
  We present our investigation into the long-term variability of the X-ray
obscuration and optical-UV-X-ray continuum in the Seyfert 1 galaxy NGC 5548. In
2013 and 2014, the Swift observatory monitored NGC 5548 on average every day or
two, with archival observations reaching back to 2005, totalling about 670 ks
of observing time. Both broadband spectral modelling and temporal rms
variability analysis are applied to the Swift data. We disentangle the
variability caused by absorption, due to an obscuring weakly-ionised outflow
near the disk, from variability of the intrinsic continuum components (the soft
X-ray excess and the power-law) originating from the disk and its associated
coronae. The spectral model that we apply to this extensive Swift data is the
global model that we derived for NGC 5548 from analysis of the stacked spectra
from our multi-satellite campaign of summer 2013 (including XMM-Newton, NuSTAR
and HST). The results of our Swift study show that changes in the covering
fraction of the obscurer is the primary and dominant cause of variability in
the soft X-ray band on timescales of 10 days to ~ 5 months. The obscuring
covering fraction of the X-ray source is found to range between 0.7 and nearly
1.0. The contribution of the soft excess component to the X-ray variability is
often much less than that of the obscurer, but it becomes comparable when the
optical-UV continuum flares up. We find that the soft excess is consistent with
being the high-energy tail of the optical-UV continuum and can be explained by
warm Comptonisation: up-scattering of the disk seed photons in a warm,
optically thick corona as part of the inner disk. To this date, the Swift
monitoring of NGC 5548 shows that the obscurer has been continuously present in
our line of sight for at least 4 years (since at least February 2012).


title:
A class of solutions to the Einstein equations with AVTD behavior in
  generalized wave gauges

abstract:
  We establish the existence of smooth vacuum Gowdy solutions, which are
asymptotically velocity term dominated (AVTD) and have T3-spatial topology, in
an infinite dimensional family of generalized wave gauges. These results show
that the AVTD property, which is known to hold for solutions in areal
coordinates, is stable to perturbations with respect to the gauge source
functions. Our proof is based on an analysis of the singular initial value
problem for the Einstein vacuum equations in the generalized wave gauge
formalism, and provides a framework which we anticipate to be useful for more
general spacetimes.


title: Getting used to quantum optics

abstract:
  The article reviews how to measure one and the same photon at both output
ports of a beam splitter.


title: On $\kappa$-reducibility of pseudovarieties of the form $\bf V*\bf D$

abstract:
  This paper deals with the reducibility property of semidirect products of the
form $\bf V*\bf D$ relatively to graph equation systems, where $\bf D$ denotes
the pseudovariety of definite semigroups. We show that, if the pseudovariety
$\bf V$ is reducible with respect to the canonical signature $\kappa$
consisting of the multiplication and the $(\omega-1)$-power, then $\bf V*\bf D$
is also reducible with respect to $\kappa$.


title:
L-mode filament characteristics on MAST as a function of plasma current
  measured using visible imaging

abstract:
  Clear filamentary structures are observed at the edge of tokamak plasmas.
These filaments are ejected out radially and carry plasma in the far Scrape Off
Layer (SOL) region, where they are responsible for producing most of the
transport. A study has been performed of the characteristics of the filaments
observed in L-mode plasma on MAST, using visible imaging. A comparison has then
been made with the observed particle and power profiles obtained at the
divertor as a function of the plasma current. The radial velocity and to a
lesser extent the radial size of the filaments are found to decrease as the
plasma current is increased at constant density and input power. The results
obtained in this paper on the dependence of the average filament dynamics on
plasma current are consistent with the idea that the filaments are responsible
for determining the particle profiles at the divertor.


title: The First Brown Dwarf/Planetary-Mass Object in the 32 Orionis Group

abstract:
  The 32 Orionis group is a co-moving group of roughly 20 young (24 Myr) M3-B5
stars 100 pc from the Sun. Here we report the discovery of its first substellar
member, WISE J052857.69+090104.2. This source was previously reported to be an
M giant star based on its unusual near-infrared spectrum and lack of measurable
proper motion. We re-analyze previous data and new moderate-resolution
spectroscopy from Magellan/FIRE to demonstrate that this source is a young
near-infrared L1 brown dwarf with very low surface gravity features. Spectral
model fits indicate T$_{eff}$ = 1880$^{+150}_{-70}$ K and $\log{g}$ =
3.8$^{+0.2}_{-0.2}$ (cgs), consistent with a 15-22 Myr object with a mass near
the deuterium-burning limit. Its sky position, estimated distance, kinematics
(both proper motion and radial velocity), and spectral characteristics are all
consistent with membership in 32 Orionis, and its temperature and age imply a
mass (M = 14$^{+4}_{-3}$ M$_{Jup}$) that straddles the brown
dwarf/planetary-mass object boundary. The source has a somewhat red $J-W2$
color compared to other L1 dwarfs, but this is likely a low-gravity-related
temperature offset; we find no evidence of significant excess reddening from a
disk or cool companion in the 3-5 $\mu$m waveband.


title:
Model for probing membrane-cortex adhesion by micropipette aspiration
  and fluctuation spectroscopy

abstract:
  We propose a model for membrane-cortex adhesion which couples membrane
deformations, hydrodynamics and kinetics of membrane-cortex ligands. In its
simplest form, the model gives explicit predictions for the critical pressure
for membrane detachment and for the value of adhesion energy. We show that
these quantities exhibit a significant dependence on the active acto-myosin
stresses. The model provides a simple framework to access quantitative
information on cortical activity by means of micropipette experiments. We also
extend the model to incorporate fluctuations and show that detailed information
on the stability of membrane-cortex coupling can be obtained by a combination
of micropipette aspiration and fluctuation spectroscopy measurements.


title: Stable Switching among High-Order Modes in Polariton Condensates

abstract:
  We report multistate optical switching among high-order bouncing-ball modes
("ripples") and whispering-gallerying modes ("petals") of exciton-polariton
condensates in a laser-generated annular trap. By tailoring the diameter and
power of the annular trap, the polariton condensate can be switched among
different trapped modes, accompanied by redistribution of spatial densities and
superlinear increase in the emission intensities, implying that polariton
condensates in this geometry could be exploited for a multistate switch. A
model based on non-Hermitian modes of the generalized Gross-Pitaevskii equation
reveals that this mode switching arises from competition between pump-induced
gain and in-plane polariton loss. The parameters for reproducible switching
among trapped modes have been measured experimentally, giving us a phase
diagram for mode switching. Taken together, the experimental result and
theoretical modeling advances our fundamental understanding of the spontaneous
emergence of coherence and move us toward its practical exploitation.


title: R\'egulateurs modulaires explicites via la m\'ethode de Rogers-Zudilin

abstract:
  We compute the regulator of Beilinson-Deninger-Scholl elements in terms of
special values of L-functions of modular forms, using the Rogers-Zudilin
method.


title: Engineering and Suppression of Decoherence in Two Qubit Systems

abstract:
  In this work, two experimentally feasible methods of decoherence
engineering-one based on the application of stochastic classical kicks and the
other based on temporally randomized pulse sequences are combined. A different
coupling interaction is proposed, which leads to amplitude damping as compared
to existing methods which model phase damping, utilizing the $zz$ coupling
interaction. The decoherence process on combining the stochastic kick method
and the randomized pulse sequence method and the effectiveness of dynamical
decoupling under these coupling interactions are analyzed. Finally, a
counter-intuitive result where decoherence is suppressed in the presence of two
noise sources under certain resonant conditions is presented.


title: Minimax Lower Bounds for Realizable Transductive Classification

abstract:
  Transductive learning considers a training set of $m$ labeled samples and a
test set of $u$ unlabeled samples, with the goal of best labeling that
particular test set. Conversely, inductive learning considers a training set of
$m$ labeled samples drawn iid from $P(X,Y)$, with the goal of best labeling any
future samples drawn iid from $P(X)$. This comparison suggests that
transduction is a much easier type of inference than induction, but is this
really the case? This paper provides a negative answer to this question, by
proving the first known minimax lower bounds for transductive, realizable,
binary classification. Our lower bounds show that $m$ should be at least
$\Omega(d/\epsilon + \log(1/\delta)/\epsilon)$ when $\epsilon$-learning a
concept class $\mathcal{H}$ of finite VC-dimension $d<\infty$ with confidence
$1-\delta$, for all $m \leq u$. This result draws three important conclusions.
First, general transduction is as hard as general induction, since both
problems have $\Omega(d/m)$ minimax values. Second, the use of unlabeled data
does not help general transduction, since supervised learning algorithms such
as ERM and (Hanneke, 2015) match our transductive lower bounds while ignoring
the unlabeled test set. Third, our transductive lower bounds imply lower bounds
for semi-supervised learning, which add to the important discussion about the
role of unlabeled data in machine learning.


title:
Multi-messenger signals of long-term core-collapse supernova simulations
  : synergetic observation strategies

abstract:
  The next Galactic supernova is expected to bring great opportunities for the
direct detection of gravitational waves (GW), full flavor neutrinos, and
multi-wavelength photons. To maximize the science return from such a rare
event, it is essential to have established classes of possible situations and
preparations for appropriate observations. To this end, we use a long-term
numerical simulation of the core-collapse supernova (CCSN) of a 17 solar-mass
red supergiant progenitor to self-consistently model the multi-messenger
signals expected in GW, neutrino, and electromagnetic messengers. This
supernova model takes into account the formation and evolution of a
protoneutron star, neutrino-matter interaction, and neutrino transport, all
within a two-dimensional shock hydrodynamics simulation. With this, we
separately discuss three situations: (i) a CCSN at the Galactic Center, (ii) an
extremely nearby CCSN within hundreds of parsecs, and (iii) a CCSN in nearby
galaxies within several Mpc. These distance regimes necessitate different
strategies for synergistic observations. In a Galactic CCSN, neutrinos provide
strategic timing and pointing information. We explore how these in turn deliver
an improvement in the sensitivity of GW analyses and help to guarantee
observations of early electromagnetic signals. To facilitate the detection of
multi-messenger signals of CCSNe in extremely nearby and extragalactic
distances, we compile a list of nearby red supergiant candidates and a list of
nearby galaxies with their expected CCSN rates. By exploring the sequential
multi-messenger signals of a nearby CCSN, we discuss preparations for
maximizing successful studies of such an unprecedented stirring event.

categories: astro-ph.HE gr-qc hep-ex physics.ins-det


title: Readout of relaxation rates by nonadiabatic pumping spectroscopy

abstract:
  We put forward nonadiabatic charge pumping as a method for accessing the
different charge relaxation rates as well as the relaxation rates of excited
orbital states in double-quantum-dot setups, based on extremely size-limited
quantum dots and dopant systems. The rates are obtained in a well-separated
manner from plateaus, occurring when comparing the steady-state current for
reversed driving cycles. This yields a reliable readout independent of any
fitting parameters. Importantly, the nonadiabatic pumping spectroscopy
essentially exploits the same driving scheme as the operation of these devices
generally employs. We provide a detailed analysis of the working principle of
the readout scheme as well as of possible errors, thereby demonstrating its
broad applicability. The precise knowledge of relaxation rates is highly
relevant for the implementation of time-dependently operated devices, such as
electron pumps for metrology or qubits in quantum information.


title:
Angular distributions of $\bar B \to D^{(\ast)}\ell\bar \nu_\ell$ decays
  and search of New Physics

abstract:
  We derive the expressions for the full angular distributions of $\bar B\to
D\ell\bar \nu_\ell$ and $\bar B\to D^{\ast }\ell\bar \nu_\ell$ decays and
discuss the spectra on each angle separately. The coefficient functions,
depending on helicity amplitudes, can then be combined in an ensemble of
observables which can then be used to check for the presence of New Physics. We
examine the sensitivity of each of these observables on the presence of
non-Standard Model interaction terms at low energies. The expressions presented
here are general and can be used for studying any other semileptonic
pseudoscalar to pseudoscalar/vector meson decay. We also examine the problem of
pollution of the $\bar B\to D^{\ast}(\to D\pi)_S\ell\bar \nu_\ell$ decay sample
by the $\bar B\to D_0^{\ast}(\to D\pi)\ell\bar \nu_\ell$ events, and point out
that a measurement of two particular quantities could clarify whether or not
the $(D\pi)_{S-\rm wave}$ in the vicinity of $D^\ast$-peak is (approximately)
described by the Breit-Wigner formula.


title: Coinami: A Cryptocurrency with DNA Sequence Alignment as Proof-of-work

abstract:
  Rate of growth of the amount of data generated using the high throughput
sequencing (HTS) platforms now exceeds the growth stipulated by Moore's Law.
The HTS data is expected to surpass those of other "big data" domains such as
astronomy, before the year 2025. In addition to sequencing genomes for research
purposes, genome and exome sequencing in clinical settings will be a routine
part of health care. The analysis of such large amounts of data, however, is
not without computational challenges. This burden is even more increased due to
the periodic updates to reference genomes, which typically require re-analysis
of existing data. Here we propose Coin-Application Mediator Interface (Coinami)
to distribute the workload for mapping reads to reference genomes using a
volunteer grid computer approach similar to Berkeley Open Infrastructure for
Network Computing (BOINC). However, since HTS read mapping requires substantial
computational resources and fast analysis turnout is desired, Coinami uses the
HTS read mapping as proof-of-work to generate valid blocks to main its own
cryptocurrency system, which may help motivate volunteers to dedicate more
resources. The Coinami protocol includes mechanisms to ensure that jobs
performed by volunteers are correct, and provides genomic data privacy. The
prototype implementation of Coinami is available at http://coinami.github.io/.


title: Associative Long Short-Term Memory

abstract:
  We investigate a new method to augment recurrent neural networks with extra
memory without increasing the number of network parameters. The system has an
associative memory based on complex-valued vectors and is closely related to
Holographic Reduced Representations and Long Short-Term Memory networks.
Holographic Reduced Representations have limited capacity: as they store more
information, each retrieval becomes noisier due to interference. Our system in
contrast creates redundant copies of stored information, which enables
retrieval with reduced noise. Experiments demonstrate faster learning on
multiple memorization tasks.


title: Strengthening the Entropy Power Inequality

abstract:
  We tighten the Entropy Power Inequality (EPI) when one of the random summands
is Gaussian. Our strengthening is closely connected to the concept of strong
data processing for Gaussian channels and generalizes the (vector extension of)
Costa's EPI. This leads to a new reverse entropy power inequality and, as a
corollary, sharpens Stam's inequality relating entropy power and Fisher
information. Applications to network information theory are given, including a
short self-contained proof of the rate region for the two-encoder quadratic
Gaussian source coding problem.
  Our argument is based on weak convergence and a technique employed by Geng
and Nair for establishing Gaussian optimality via rotational-invariance, which
traces its roots to a `doubling trick' that has been successfully used in the
study of functional inequalities.


title: The generators and relations picture of $KK$-theory

abstract:
  This is half an overview article since what we describe here is essentially
known. We describe $KK$-theory by generators and relations in a formal sum of
formal products of $*$-homomorphisms and some synthetical morphisms. What comes
out is a category. The Kasparov product is then just the composition of
morphisms. This description may be interesting to anyone who wants a quick and
elementary definition of $KK$-theory. The description could also be used for
other categories of algebras than $C^*$-algebras endowed with group actions,
for example, $C^*$-algebras equipped with an action by a semigroup, a category
et cetera.


title:
Numerical calculation of scaling exponents of percolation process in the
  framework of renormalization group approach

abstract:
  We use the renormalization group theory to study the directed bond
percolation (Gribov process) near its second-order phase transition between
absorbing and active state. We present a numerical calculation of the
renormalization group functions in the $\epsilon$-expansion where $\epsilon$ is
a deviation from the upper critical dimension $d_c = 4$. Within this procedure
anomalous dimensions $\gamma$ are expressed in terms of irreducible
renormalized Feynman diagrams and thus the calculation of renormalization
constants could be entirely skipped. The renormalization group is included by
means of the $R$ operation, and for computational purposes we choose the null
momentum subtraction scheme.


title:
Constraints on the neutrino emission from the Galactic Ridge with the
  ANTARES telescope

abstract:
  Compelling evidence for the existence of astrophysical neutrinos has been
reported by the IceCube collaboration. Some features of the energy and
declination distributions of IceCube events hint at a North/South asymmetry of
the neutrino flux. This could be due to the presence of the bulk of our Galaxy
in the Southern hemisphere. The ANTARES neutrino telescope, located in the
Mediterranean Sea, has been taking data since 2007. It offers the best
sensitivity to muon neutrinos produced by galactic cosmic ray interactions in
this region of the sky. In this letter a search for an extended neutrino flux
from the Galactic Ridge region is presented. Different models of neutrino
production by cosmic ray propagation are tested. No excess of events is
observed and upper limits for different neutrino flux spectral indices are set.
This constrains the number of IceCube events possibly originating from the
Galactic Ridge. A simple power-law extrapolation of the Fermi-LAT flux to
associated IceCube High Energy Starting Events is excluded at 90% confidence
level.


title:
Effect of turbulence on collisions of dust particles with planetesimals
  in protoplanetary disks

abstract:
  Planetesimals in gaseous protoplanetary disks may grow by collecting dust
particles. Hydrodynamical studies show that small particles generally avoid
collisions with the planetesimals because they are entrained by the flow around
them. This occurs when $St$, the Stokes number, defined as the ratio of the
dust stopping time to the planetesimal crossing time, becomes much smaller than
unity. However, these studies have been limited to the laminar case, whereas
these disks are believed to be turbulent. We want to estimate the influence of
gas turbulence on the dust-planetesimal collision rate and on the impact
speeds. We used three-dimensional direct numerical simulations of a fixed
sphere (planetesimal) facing a laminar and turbulent flow seeded with small
inertial particles (dust) subject to a Stokes drag. A no-slip boundary
condition on the planetesimal surface is modeled via a penalty method. We find
that turbulence can significantly increase the collision rate of dust particles
with planetesimals. For a high turbulence case (when the amplitude of turbulent
fluctuations is similar to the headwind velocity), we find that the collision
probability remains equal to the geometrical rate or even higher for $St\geq
0.1$, i.e., for dust sizes an order of magnitude smaller than in the laminar
case. We derive expressions to calculate impact probabilities as a function of
dust and planetesimal size and turbulent intensity.


title:
Determining graphene's induced band gap with magnetic and electric
  emitters

abstract:
  We present numerical and analytical results for the lifetime of emitters in
close proximity to graphene sheets. Specifically, we analyze the contributions
from different physical channels that participate in the decay processes. Our
results demonstrate that measuring the emitters' decay rates provides an
efficient route for sensing graphene's optoelectronic properties, notably the
existence and size of a potential band gap in its electronic band structure.


title:
Geometry of Quiver Grassmannians of Dynkin type with applications to
  cluster algebras

abstract:
  The paper includes a new proof of the fact that quiver Grassmannians
associated with rigid representations of Dynkin quivers do not have cohomology
in odd degrees. Moreover, it is shown that they do not have torsion in
homology. A new proof of the Caldero--Chapoton formula is provided. As a
consequence a new proof of the positivity of cluster monomials in the acyclic
clusters associated with Dynkin quivers is obtained. The methods used here are
based on joint works with Markus Reineke and Evgeny Feigin.


title: The Structured Weighted Violations Perceptron Algorithm

abstract:
  We present the Structured Weighted Violations Perceptron (SWVP) algorithm, a
new structured prediction algorithm that generalizes the Collins Structured
Perceptron (CSP). Unlike CSP, the update rule of SWVP explicitly exploits the
internal structure of the predicted labels. We prove the convergence of SWVP
for linearly separable training sets, provide mistake and generalization
bounds, and show that in the general case these bounds are tighter than those
of the CSP special case. In synthetic data experiments with data drawn from an
HMM, various variants of SWVP substantially outperform its CSP special case.
SWVP also provides encouraging initial dependency parsing results.


title:
Lagrangian controllability of inviscid perfect fluids: a constructive
  approach

abstract:
  We present here a constructive method of Lagrangian approximate control-
lability for the Euler equation. We emphasize on different options that could
be used for numerical recipes: either, in the case of a bi-dimensionnal fluid,
the use of formal com- putations in the framework of explicit Runge
approximations of holomorphic functions by rational functions, or an approach
based on the study of the range of an operator by showing a density result. For
this last insight in view of numerical simulations in progress, we analyse
through a simplified problem the observed instabilities.


title: Automatic sequences fulfill the Sarnak conjecture

abstract:
  We present in this paper a new method to deal with automatic sequences.
  This method allows us to prove a M\"obius-randomness-principle for automatic
sequences from which we deduce the Sarnak conjecture for this class of
sequences.
  Furthermore, we can show a Prime Number Theorem for automatic sequences that
are generated by strongly connected automata where the initial state is fixed
by the transition corresponding to $0$.


title: The square-root impact law also holds for option markets

abstract:
  Many independent studies on stocks and futures contracts have established
that market impact is proportional to the square-root of the executed volume.
Is market impact quantitatively similar for option markets as well? In order to
answer this question, we have analyzed the impact of a large proprietary data
set of option trades. We find that the square-root law indeed holds in that
case. This finding supports the argument for a universal underlying mechanism.


title: Perturbation theory for the Fokker-Planck operator in chaos

abstract:
  The stationary distribution of a fully chaotic system typically exhibits a
fractal structure, which dramatically changes if the dynamical equations are
even slightly modified. Perturbative techniques are not expected to work in
this situation. In contrast, the presence of additive noise smooths out the
stationary distribution, and perturbation theory becomes applicable. We show
that a perturbation expansion for the Fokker-Planck evolution operator yields
surprisingly accurate estimates of long-time averages in an otherwise unlikely
scenario.


title: Lagrangian controllability at low Reynolds number

abstract:
  In this paper, we establish a result of Lagrangian controllability for a
fluid at low Reynolds number, driven by the stationary Stokes equation. This
amounts to the possibility of displacing a part of a fluid from one zone to
another by suitably using a boundary control. This relies on a weak variant of
the Runge-Walsh's theorem (on approximation of harmonic functions) concerning
the Stokes equation. We give two variants of this result, one of which we
believe to be better adapted to numerical simulations.


title: Efficient Breeding by Genomic Mating

abstract:
  In this article, we propose an approach to breeding which focuses on mating
instead of truncation selection, our method uses genome-wide marker information
in a similar fashion to genomic selection so we refer it to as genomic mating.
Using concepts of estimated breeding values, risk (usefulness) and inbreeding,
an efficient mating approach is formulated for improvement of breeding values
in the long run. We have used a genetic algorithm to find solutions to this
optimization problem. Results from our simulations point to the efficiency of
genomic mating for breeding complex traits compared to truncation selection.


title: C*-tensor categories and subfactors for totally disconnected groups

abstract:
  We associate a rigid C*-tensor category $C$ to a totally disconnected locally
compact group $G$ and a compact open subgroup $K < G$. We characterize when $C$
has the Haagerup property or property (T), and when $C$ is weakly amenable.
When $G$ is compactly generated, we prove that $C$ is essentially equivalent to
the planar algebra associated by Jones and Burstein to a group acting on a
locally finite bipartite graph. We then concretely realize $C$ as the category
of bimodules generated by a hyperfinite subfactor.


title:
Bayesian nonparametric image segmentation using a generalized
  Swendsen-Wang algorithm

abstract:
  Unsupervised image segmentation aims at clustering the set of pixels of an
image into spatially homogeneous regions. We introduce here a class of Bayesian
nonparametric models to address this problem. These models are based on a
combination of a Potts-like spatial smoothness component and a prior on
partitions which is used to control both the number and size of clusters. This
class of models is flexible enough to include the standard Potts model and the
more recent Potts-Dirichlet Process model \cite{Orbanz2008}. More importantly,
any prior on partitions can be introduced to control the global clustering
structure so that it is possible to penalize small or large clusters if
necessary. Bayesian computation is carried out using an original generalized
Swendsen-Wang algorithm. Experiments demonstrate that our method is competitive
in terms of RAND\ index compared to popular image segmentation methods, such as
mean-shift, and recent alternative Bayesian nonparametric models.


title:
What powers the starburst activity of NGC 1068? Star-driven
  gravitational instabilities caught in the act

abstract:
  We explore the role that gravitational instability plays in NGC 1068, a
nearby Seyfert galaxy that exhibits unusually vigorous starburst activity. For
this purpose, we use the Romeo-Falstad disc instability diagnostics and data
from BIMA SONG, SDSS and SAURON. Our analysis illustrates that NGC 1068 is a
gravitationally unstable "monster". Its starburst disc is subject to unusually
powerful instabilities. Several processes, including AGN/stellar feedback, try
to quench such instabilities from inside out by depressing the surface density
of molecular gas across the central kpc, but they do not succeed. Gravitational
instability "wins" because it is driven by the stars via their much higher
surface density. In this process, stars and molecular gas are strongly coupled,
and it is such a coupling that ultimately triggers local gravitational
collapse/fragmentation in the molecular gas.

categories: astro-ph.GA astro-ph.CO physics.flu-dyn physics.plasm-ph


title: Complete Problems of Propositional Logic for the Exponential Hierarchy

abstract:
  Large complexity classes, like the exponential time hierarchy, received
little attention in terms of finding complete problems. In this work a
generalization of propositional logic is investigated which fills this gap with
the introduction of Boolean higher-order quantifiers or equivalently Boolean
Skolem functions. This builds on the important results of Wrathall and
Stockmeyer regarding complete problems, namely QBF and QBF-k, for the
polynomial hierarchy. Furthermore it generalizes the Dependency QBF problem
introduced by Peterson, Reif and Azhar which is complete for NEXP, the first
level of the exponential hierarchy. Also it turns out that the hardness results
do not collapse at the consideration of conjunctive and disjunctive normal
forms, in contrast to plain QBF.


title:
Quantum oscillation and nontrivial transport in the Dirac Semimetal
  Cd3As2 nanodevice

abstract:
  Here we demonstrate the Shubnikov de Haas oscillation in high-quality Cd3As2
nanowires grown by a chemical vapor deposition approach. The dominant transport
of topological Dirac fermions is evident by the nontrivial Berry phase in the
Landau Fan diagram. The quantum oscillations rise at a small field of 2 Tesla
and preserves till up to 100K, revealing a sizeable Landau level gap and a
mobility of over 2000 cm2/V-1s-1. The angle-variable oscillations indicates the
isotropy of the bulk Dirac transport. The large estimated mean free path
appeals the one-dimensional transport of Dirac semimetals.


title: On the cohomology of Fano varieties and the Springer correspondence

abstract:
  In this paper we compute the cohomology of the Fano varieties of $k$-planes
in the smooth complete intersection of two quadrics in $\mathbb{P}^{2g+1}$,
using Springer theory for symmetric spaces.


title: Congestion Dynamics in Pedestrian Single-File Motion

abstract:
  This article considers execution and analysis of laboratory experiments of
pedestrians moving in a quasi-one-dimensional system with periodic boundary
conditions. To analyze characteristics of jams in the system we aim to use the
whole experimental setup as the measurement area. Thus the trajectories are
transformed to a new coordinate system. We show that the trajectory data from
the straight and curved parts are comparable and assume that the distributions
of the residuals come from the same continuous distribution. Regarding the
trajectories of the entire setup, the creation of stop-and-go waves in
pedestrian traffic can be investigated and described.


title: Tutte's invariant approach for Brownian motion reflected in the quadrant

abstract:
  We consider a Brownian motion with drift in the quarter plane with orthogonal
reflection on the axes. The Laplace transform of its stationary distribution
satisfies a functional equation, which is reminiscent from equations arising in
the enumeration of (discrete) quadrant walks. We develop a Tutte's invariant
approach to this continuous setting, and we obtain an explicit formula for the
Laplace transform in terms of generalized Chebyshev polynomials.


title:
Multi-state stochastic hotchpotch model gives rise to the observed
  mesoscopic behaviour in the non-stirred Belousov--Zhabotinsky reaction

abstract:
  Mesoscopic dynamics of self-organized structures is the most important aspect
in the description of complex living systems. The Belousov--Zhabotinsky (B--Z)
reaction is in this respect a convenient testbed because it represents a
prototype of chemical self-organization with a rich variety of emergent
wave-spiral patterns. Using a multi-state stochastic hotchpotch model, we show
here that the mesoscopic behaviour of the non-stirred B--Z reaction is both
qualitatively and quantitatively susceptible to the description in terms of
stochastic multilevel cellular automata. This further implies that the
mesoscopic dynamics of the non-stirred B--Z reaction results from a delicate
interplay between a) a maximal number of available states within the elementary
time lag (i.e. a minimal time interval needed for demise of a final state) and
b) an imprecision or uncertainty in the definition of state. If either the
number of time lags is largely different from 7 or the maximal number of
available states is smaller than 20, the physicochemical conditions are
inappropriate for a formation of the wave-spiral patterns. Furthermore, a white
noise seems to be key for the formation of circular structures (target
patterns) which could not be as yet systematically explained in existing
models.


title: Asteroseismic signatures of evolving internal stellar magnetic fields

abstract:
  Recent asteroseismic analyses have revealed the presence of strong (B
$\gtrsim 10^5$ G) magnetic fields in the cores of many red giant stars. Here,
we examine the implications of these results for the evolution of stellar
magnetic fields, and we make predictions for future observations. Those stars
with suppressed dipole modes indicative of strong core fields should exhibit
moderate but detectable quadrupole mode suppression. The long magnetic
diffusion times within stellar cores ensure that dynamo-generated fields are
confined to mass coordinates within the main sequence convective core, and the
observed sharp increase in dipole mode suppression rates above $1.5 \, M_\odot$
may be explained by the larger convective core masses and faster rotation of
these more massive stars. In clump stars, core fields of $\sim10^5 \, {\rm G}$
can suppress dipole modes, whose visibility should be equal to or less than the
visibility of suppressed modes in ascending red giants. High dipole mode
suppression rates in low-mass ($M \lesssim 2 \, M_\odot$) clump stars would
indicate that magnetic fields generated during the main sequence can withstand
subsequent convective phases and survive into the compact remnant phase.
Finally, we discuss implications for observed magnetic fields in white dwarfs
and neutron stars, as well as the effects of magnetic fields in various types
of pulsating stars.


title: Horizon Thermodynamics and Gravitational Tension

abstract:
  We consider the thermodynamics of a horizon surface from the viewpoint of the
vacuum tension $\tau =(c^4/4G )$. Numerically, $\tau \approx 3.026\times
10^{43}$ Newton. In order of magnitude, this is the tension that has been
proposed for microscopic string models of gravity. However, after decades of
hard work on string theory models of gravity, there is no firm scientific
evidence that such models of gravity apply empirically. Our purpose is thereby
to discuss the gravitational tension in terms of the conventional Einstein
general theory of relativity that apparently does explain much and maybe all of
presently known experimental gravity data. The central result is that matter on
the horizon surface is bound by the entropy-area law by tension in the closely
analogous sense that the Wilson action-area law also describes a surface
confinement.


title:
Theory of Metallic Work Functions Between Metals and Layers of Exclusion
  Zone Ordered Water

abstract:
  The magnitude of the work function to bring an electron from a metal into the
exclusion zone water layer making hydrophilic contact with the metallic
interface is theoretically computed. The agreement with recent experimental
measurements is satisfactory.


title:
Determination of small linear perturbations in the diffusion coefficient
  from partial dynamic boundary measurements

abstract:
  This work deals with an inverse boundary value problem arising from the
equation of heat conduction. We reconstruct small perturbations of the
(isotropic) heat conductivity distribution from partial (on accessible part of
the boundary) dynamic boundary measurements and for finite interval in time. By
constructing of appropriate test functions, using a control method, we provide
a rigorous derivation of the inverse Fourier transform of the perturbations in
the diffusion coefficient as the leading order of an appropriate averaging of
the partial dynamic boundary measurements.


title: Liouville's Theorem from the Principle of Maximum Caliber in Phase Space

abstract:
  One of the cornerstones in non--equilibrium statistical mechanics (NESM) is
Liouville's theorem, a differential equation for the phase space probability
$\rho(q,p; t)$. This is usually derived considering the flow in or out of a
given surface for a physical system (composed of atoms), via more or less
heuristic arguments.
  In this work, we derive the Liouville equation as the partial differential
equation governing the dynamics of the time-dependent probability $\rho(q, p;
t)$ of finding a "particle" with Lagrangian $L(q, \dot{q}; t)$ in a specific
point $(q, p)$ in phase space at time $t$, with $p=\partial L/\partial
\dot{q}$. This derivation depends only on considerations of inference over a
space of continuous paths. Because of its generality, our result is valid not
only for "physical" systems but for any model depending on constrained
information about position and velocity, such as time series.


title:
Minimum Conditional Description Length Estimation for Markov Random
  Fields

abstract:
  In this paper we discuss a method, which we call Minimum Conditional
Description Length (MCDL), for estimating the parameters of a subset of sites
within a Markov random field. We assume that the edges are known for the entire
graph $G=(V,E)$. Then, for a subset $U\subset V$, we estimate the parameters
for nodes and edges in $U$ as well as for edges incident to a node in $U$, by
finding the exponential parameter for that subset that yields the best
compression conditioned on the values on the boundary $\partial U$. Our
estimate is derived from a temporally stationary sequence of observations on
the set $U$. We discuss how this method can also be applied to estimate a
spatially invariant parameter from a single configuration, and in so doing,
derive the Maximum Pseudo-Likelihood (MPL) estimate.


title: Temporal laser pulse shape effects in nonlinear Thomson scattering

abstract:
  The influence of the laser pulse temporal shape on the Nonlinear Thomson
Scattering on-axis photon spectrum is analyzed in detail. Using the classical
description, analytical expressions for the temporal and spectral structure of
the scattered radiation are obtained for the case of symmetric laser pulse
shapes. The possibility of reconstructing the incident laser pulse from the
scattered spectrum averaged over interference fringes in the case of high peak
intensity and symmetric laser pulse shape is discussed.


title:
Persisting fetal clonotypes influence the structure and overlap of adult
  human T cell receptor repertoires

abstract:
  The diversity of T-cell receptors recognizing foreign pathogens is generated
through a highly stochastic recombination process, making the independent
production of the same sequence rare. Yet unrelated individuals do share
receptors, which together constitute a "public" repertoire of abundant
clonotypes. The TCR repertoire is initially formed prenatally, when the enzyme
inserting random nucleotides is downregulated, producing a limited diversity
subset. By statistically analyzing deep sequencing T-cell repertoire data from
twins, unrelated individuals of various ages, and cord blood, we show that
T-cell clones generated before birth persist and maintain high abundances in
adult organisms for decades, slowly decaying with age. Our results suggest that
large, low-diversity public clones are created during pregnancy, and survive
over long periods, providing the basis of the public repertoire.


title:
Flow towards diagonalization for Many-Body-Localization models :
  adaptation of the Toda matrix differential flow to random quantum spin chains

abstract:
  The iterative methods to diagonalize matrices and many-body Hamiltonians can
be reformulated as flows of Hamiltonians towards diagonalization driven by
unitary transformations that preserve the spectrum. After a comparative
overview of the various types of discrete flows (Jacobi, QR-algorithm) and
differential flows (Toda, Wegner, White) that have been introduced in the past,
we focus on the random XXZ chain with random fields in order to determine the
best closed flow within a given subspace of running Hamiltonians. For the
special case of the free-fermion random XX chain with random fields, the flow
coincides with the Toda differential flow for tridiagonal matrices which is
related to the classical integrable Toda chain and which can be seen as the
continuous analog of the discrete QR-algorithm. For the random XXZ chain with
random fields that displays a Many-Body-Localization transition, the present
differential flow should be an interesting alternative to compare with the
discrete flow that has been proposed recently to study the
Many-Body-Localization properties in a model of interacting fermions (L.
Rademaker and M. Ortuno, Phys. Rev. Lett. 116, 010404 (2016)).


title:
Real-time dynamics in a strongly interacting bosonic hopping model:
  Global quenches and mapping to the XX chain

abstract:
  We study the time evolution of an integrable many-particle system, described
by the $q$-boson Hamiltonian in the limit of strong interactions $q\to\infty$.
It is shown that, for a particular class of pure initial states, the analytical
calculation of certain observables simplifies considerably. Namely, we provide
exact formulas for the calculation of the Loschmidt-echo and the emptiness
formation probability, where the computational time scales polynomially with
the particle number. Moreover, we construct a non-local mapping of the
$q$-boson model to the XX spin chain, and show how this can be utilized to
obtain the time evolution of various local bosonic observables for
translationally invariant initial states. The results obtained via the bosonic
and fermionic picture show perfect agreement. In the infinite volume and large
time limits, we rigorously verify the prediction of the Generalized Gibbs
Ensemble for homogeneous initial Fock states.


title: Extrinsic and intrinsic curvatures in thermodynamic geometry

abstract:
  We investigate the intrinsic and extrinsic curvatures of certain
hypersurfaces in the thermodynamic geometry of a physical system and show that
they contain useful thermodynamic information. For an
anti-Reissner-Nordstr\"{o}m-(A)de Sitter black hole (Phantom), the extrinsic
curvature of a constant $Q$ hypersurface has the same sign as the heat capacity
around the phase transition points. For a Kerr-Newmann-AdS (KN-AdS) black hole,
the extrinsic curvature of $Q \to 0$ hypersurface (Kerr black hole) or $J \to
0$ hypersurface (RN black black hole) has the same sign as the heat capacity
around the phase transition points. The extrinsic curvature also diverges at
the phase transition points. The intrinsic curvature of the hypersurfaces
diverges at the critical points but has no information about the sign of the
heat capacity. Our study explains the consistent relationship holding between
the thermodynamic geometry of the KN-AdS black holes and those of the RN and
Kerr ones \cite{ref1}. This approach can be easily generalized to an arbitrary
thermodynamic system.


title: Uniform Acceleration in General Relativity

abstract:
  We extend de la Fuente and Romero's defining equation for uniform
acceleration in a general curved spacetime from linear acceleration to the full
Lorentz covariant uniform acceleration. In a flat spacetime background, we have
explicit solutions. We use generalized Fermi-Walker transport to parallel
transport the Frenet basis along the trajectory. In flat spacetime, we obtain
velocity and acceleration transformations from a uniformly accelerated system
to an inertial system. We obtain the time dilation between accelerated clocks.
We apply our acceleration transformations to the motion of a charged particle
in a constant electromagnetic field and recover the Lorentz-Abraham-Dirac
equation.


title:
The Formation Mass of a Binary System via Fragmentation of a Rotating
  Parent Core with Increasing Total Mass

abstract:
  Recent VLA and CARMA observations have shown proto-stars in binaries with
unprecedented resolution. Specifically, the proto-stellar masses of systems
such as CB230 IRS1 and L1165-SMM1 have been detected in the range of $0.1-0.25
\, M_{\odot}$. These are much more massive than the masses generally obtained
by numerical simulations of binary formation, around $0.01 \, M_{\odot}$.
Motivated by these discrepancies in mass, in this paper we study the formation
mass of a binary system as a function of the total mass of its parent core. To
achieve this objective, we present a set of numerical simulations of the
gravitational collapse of a uniform and rotating core, in which azimuthal
symmetric mass seeds are initially implemented in order to favor the formation
of a dense filament, out of which a binary system may be formed by direct
fragmentation. We first observed that this binary formation process is
diminished when the total mass of the parent core $M_0$ is increased; then we
increased the level of the ratio of kinetic energy to the gravitational energy,
denoted by $\beta$, initially supplied to the rotating core, in order to
achieve the desired direct fragmentation of the filament. Next, we found that
the mass of the binary fragment increases with the mass of the parent core, as
expected. In this paper we confirm this expectation and also measure the binary
mass $M_f$ obtained from an initial $M_0$. We then show a schematic diagram
$M_0$ vs $\beta$, where the desired binary configurations are located while the
ratio of the thermal energy to the gravitational energy $\alpha$ is kept fixed.
We also report some basic physical data of the proto-stellar fragments that
form the binary system, including the formation mass $M_f$, and its
corresponding $\alpha_f$ and $\beta_f$.


title:
Trouble with the Drude theory of metallic conduction: Incompatibility
  with special relativity

abstract:
  In this paper, we show that the classical Drude model of electrical
conductivity, one of the fundamental models in the theory of electrical
conductivity, is inconsistent with the special relativity. Due to this
incorrect model, a current carrying closed circuit is thought not to produce
second order electric field according to Maxwell's theory of electromagnetism.
But, Edwards et al. detected a small second order electric field radially
pointing toward a current carrying conductor in a superconducting Nb-Ti coil.
Assis et al. claim to show that Maxwell's theory does not predict any second
order forces and hence we should take Weber's electrodynamics seriously. But,
we show that not only a magnetic field, but also a second order electric field
is produced in the vicinity of a current carrying conductor, which is
consistent with Maxwell's theory. This electric field points radially toward
the current carrying conductor as detected in Edwards' experiments. We also
show that the positive field, detected by Sansbury in a U-shaped copper
conductor carrying a constant current, should be created as a consequence of
our theory. We then estimate the order of the strength of this electric field
and show that it is in agreement with the experimental values.


title: Legendre Functions of Fractional Degree: Transformations and Evaluations

abstract:
  Associated Legendre functions of fractional degree appear in the solution of
boundary value problems in wedges or in toroidal geometries, and elsewhere in
applied mathematics. In the classical case when the degree is half an odd
integer, they can be expressed using complete elliptic integrals. In this
study, many transformations are derived, which reduce the case when the degree
differs from an integer by one-third, one-fourth or one-sixth to the classical
case. These transformations, or identities, facilitate the symbolic
manipulation and evaluation of Legendre and Ferrers functions. They generalize
both Ramanujan's transformations of elliptic integrals and Whipple's formula,
which relates Legendre functions of the first and second kinds. The proofs
employ algebraic coordinate transformations, specified by algebraic curves.


title:
Direct versus indirect band gap emission and exciton-exciton
  annihilation in atomically thin molybdenum ditelluride (MoTe$_2$)

abstract:
  We probe the room temperature photoluminescence of $N$-layer molybdenum
ditelluride (MoTe$_2$) in the continuous wave (cw) regime. The
photoluminescence quantum yield of monolayer MoTe$_2$ is three times larger
than in bilayer MoTe$_2$ and forty times greater than in the bulk limit. Mono-
and bilayer MoTe$_2$ display almost symmetric emission lines at $1.10~\rm eV$
and $1.07~\rm eV$, respectively, which predominantly arise from direct
radiative recombination of the A exciton. In contrast, $N\geq3-$layer MoTe$_2$
exhibits a much reduced photoluminescence quantum yield and a broader,
redshifted and seemingly bimodal photoluminescence spectrum. The low- and
high-energy contributions are attributed to emission from the indirect and
direct optical band gaps, respectively. Bulk MoTe$_2$ displays a broad emission
line with a dominant contribution at 0.94~eV that is assigned to emission from
the indirect optical band gap. As compared to related systems (such as MoS$_2$,
MoSe$_2$, WS$_2$ and WSe$_2$), the smaller energy difference between the
monolayer direct optical band gap and the bulk indirect optical band gap leads
to a smoother increase of the photoluminescence quantum yield as $N$ decreases.
In addition, we study the evolution of the photoluminescence intensity in
monolayer MoTe$_2$ as a function of the exciton formation rate $W_\mathrm{abs}$
up to $3.6\times 10^{22}~\rm{cm}^{-2} s^{-1}$. The lineshape of the
photoluminescence spectrum remains largely independent of $W_\mathrm{abs}$,
whereas the photoluminescence intensity grows sub-linearly above
$W_\mathrm{abs}\sim 10^{21}~\rm cm^{-2} s^{-1}$. This behavior is assigned to
exciton-exciton annihilation and is well-captured by an elementary rate
equation model.


title: Big Graph Mining: Frameworks and Techniques

abstract:
  Big graph mining is an important research area and it has attracted
considerable attention. It allows to process, analyze, and extract meaningful
information from large amounts of graph data. Big graph mining has been highly
motivated not only by the tremendously increasing size of graphs but also by
its huge number of applications. Such applications include bioinformatics,
chemoinformatics and social networks. One of the most challenging tasks in big
graph mining is pattern mining in big graphs. This task consists on using data
mining algorithms to discover interesting, unexpected and useful patterns in
large amounts of graph data. It aims also to provide deeper understanding of
graph data. In this context, several graph processing frameworks and scaling
data mining/pattern mining techniques have been proposed to deal with very big
graphs. This paper gives an overview of existing data mining and graph
processing frameworks that deal with very big graphs. Then it presents a survey
of current researches in the field of data mining / pattern mining in big
graphs and discusses the main research issues related to this field. It also
gives a categorization of both distributed data mining and machine learning
techniques, graph processing frameworks and large scale pattern mining
approaches.


title: On the Local Semicircular Law for Wigner Ensembles

abstract:
  We consider a random symmetric matrix ${\bf X} = [X_{jk}]_{j,k=1}^n$ with
upper triangular entries being i.i.d. random variables with mean zero and unit
variance. We additionally suppose that $\mathbb E |X_{11}|^{4 + \delta} =:
\mu_{4+\delta} < \infty$ for some $\delta > 0$. The aim of this paper is to
significantly extend recent result of the authors [18] and show that with high
probability the typical distance between the Stieltjes transform of the
empirical spectral distribution (ESD) of the matrix $n^{-\frac{1}{2}} {\bf X}$
and Wigner's semicircle law is of order $(nv)^{-1} \log n$, where $v$ denotes
the distance to the real line in the complex plane. We apply this result to the
rate of convergence of the ESD to the distribution function of the semicircle
law as well as to rigidity of eigenvalues and eigenvector delocalization
significantly extending a recent result by G\"otze, Naumov and Tikhomirov [19].
The result on delocalization is optimal by comparison with GOE ensembles.
Furthermore the techniques of this paper provide a new shorter proof for the
optimal $O(n^{-1})$ rate of convergence of the expected ESD to the semicircle
law.


title: Noether's theorem in non-local field theories

abstract:
  Explicit expressions are constructed for a locally conserved vector current
associated with a continuous internal symmetry and for energy-momentum and
angular-momentum density tensors associated with the Poincar\'e group in field
theories with higher-order derivatives and in non-local field theories. An
example of non-local charged scalar field equations with broken C and CPT
symmetries is considered. For this case, we find simple analytical expressions
for the conserved currents.


title: Point Sets with Small Integer Coordinates and with Small Convex Polygons

abstract:
  In 1935, Erd\H{o}s and Szekeres proved that every set of $n$ points in
general position in the plane contains the vertices of a convex polygon of
$\frac{1}{2}\log_2(n)$ vertices. In 1961, they constructed, for every positive
integer $t$, a set of $n:=2^{t-2}$ points in general position in the plane,
such that every convex polygon with vertices in this set has at most
$\log_2(n)+1$ vertices. In this paper we show how to realize their construction
in an integer grid of size $O(n^2 \log_2(n)^3)$.


title:
Hole probability for zeroes of Gaussian Taylor series with finite radii
  of convergence

abstract:
  We study a family of random Taylor series $$F(z) = \sum_{n\ge 0} \zeta_n a_n
z^n$$ with radius of convergence almost surely $1$ and independent identically
distributed complex Gaussian coefficients $(\zeta_n)$; these Taylor series are
distinguished by the invariance of their zero sets with respect to isometries
of the unit disk. We find reasonably tight upper and lower bounds on the
probability that $F$ does not vanish in the disk $\{|z|\le r\}$ as $r\uparrow
1$. Our bounds take different forms according to whether the non-random
coefficients $(a_n)$ grow, decay or remain of the same order. The results apply
more generally to a class of Gaussian Taylor series whose coefficients $(a_n)$
display power-law behavior.


title: Rank-related dimension bounds for subspaces of symmetric bilinear forms

abstract:
  Let V be a vector space of dimension n over a field K and let Symm(V) denote
the space of symmetric bilinear forms defined on V x V. Let M be a subspace of
Symm(V). We investigate a variety of hypotheses concerning the rank of elements
in M that lead to reasonable bounds for dim M. For example, if every non-zero
element of M has odd rank, and r is the maximum rank of the elements of M, then
dim M is at most r(r+1)/2 (thus dim M is bounded independently of n). This
should be contrasted with the simple observation that Symm(V) contains a
subspace of dimension n-1 in which each non-zero element has rank 2.
  The bound r(r+1)/2 is almost certainly too large, and a bound r seems
plausible, this being true when K is finite. We also show that dim M is at most
r$ when K is any field of characteristic 2.
  Finally, suppose that n=2r, where r is an odd integer, and the rank of each
non-zero element of M is either r or n. We show that if K has characteristic 2,
then dim M is at most 3r. Furthermore, if dim M=3r, we obtain interesting
subspace decompositions of M and V related to spreads, pseudo-arcs and
pseudo-ovals. Examples of such subspaces M exist if K has an extension field of
degree r.


abstract:
  For open sets $\Omega\subset \mathbb{R}^d$ we study Hadamard operators on
$\mathscr{D}'(\Omega)$, that is, continuous linear operators which admit all
monomials as eigenvectors. We characterize them as operators of the form
$L(S)=S\star T$ where $T$ is a distribution and $\star$ the multiplicative
convolution. This extends previous results for the case of
$\Omega=\mathbb{R}^d$ but requires essentially different methods.


title:
Mechanical energy fluxes associated with saturated coronal heating in M
  dwarfs: comparison with predictions of a turbulent dynamo

abstract:
  Empirically, the X-ray luminosity LX from M dwarfs has been found to have an
upper limit of about 0.2% of the bolometric flux Lbol. In the limit where
magnetic fields in M dwarfs are generated in equipartition with convective
motions, we use stellar models to calculate the energy flux of Alfven waves FA
as a function of depth in the sub-surface convection zone. Since Alfven waves
have the optimal opportunity for wave modes to reach the corona, we suggest
that FA sets an upper limit on the mechanical flux Fmech which causes coronal
heating. This suggestion accounts quantitatively for the saturated values of
LX/Lbol which have been reported empirically for M dwarfs.