title: Fragile states are better for quantum metrology

abstract:
  In quantum metrology, quantum probe states are capable of estimating unknown
physical parameters to precisions beyond classical limits. What qualities do
such states possess? Here we relate the performance of a probe state at
estimating a parameter $\phi$ -- as quantified by the quantum Fisher
information -- to the amount of purity it loses when $\phi$ undergoes
statistical fluctuation. This indicates that the better a state is for
estimating $\phi$, the more it decoheres when $\phi$ is subject to noise.


title: Chargino contributions in light of recent $\epsilon'/\epsilon$

abstract:
  Recently, the standard model prediction of $\epsilon'/\epsilon$ was improved,
and a discrepancy from the experimental results was reported at the $2.9\sigma$
level. We study the chargino contributions to $Z$ penguin especially with the
vacuum stability constraint. The vacuum decay rate is investigated, and it is
shown that the discrepancy can be explained if superparticles are lighter than
4-6 TeV. Correlations with $\mathcal{B}(K_L\to\pi^0\nu\bar\nu)$ and other
experimental constraints are also discussed.


title: On minimal graphs containing k perfect matchings

abstract:
  We call a finite undirected graph minimally k-matchable if it has at least k
distinct perfect matchings but deleting any edge results in a graph which has
not. An odd subdivision of some graph G is any graph obtained by replacing
every edge of G by a path of odd length connecting its end vertices such that
all these paths are internally disjoint. We prove that for every k>0 there
exists a finite set of graphs S(k) such that every minimally k-matchable graph
is isomorphic to a disjoint union of an odd subdivision of some graph from S(k)
and any number of copies of the complete graph on two vertices.


title:
Full Duplex Joint Sensing for Opportunistic Access in
  Spectrum-Heterogeneous Cognitive Radio Networks

abstract:
  In cognitive radio networks (CRN), secondary users (SUs) can share spectrum
with licensed primary users (PUs). Because an SU receiver (SU-Rx) does not
always share the same view of spectrum availability as the corresponding SU
transmitter (SU-Tx), spectrum sensing conducted only by an SU transmitter tends
to be overly sensitive to guarantee safe spectrum access at the price of SU
inefficiency. In this letter, we propose a joint spectrum sensing mechanism,
named Full-Duplex Joint Sensing (FJDS), to relax sensitivity of SU detection
and improve SU throughput. FDJS employs instantaneous feedback enabled by
in-band full duplex communication to facilitate the sharing of spectral
information from SU-Rx to SU-Tx. The joint detection problem in FDJS is modeled
as non-linear optimization and solved by a binary searching algorithm.
Simulation results show that FDJS could improve SU throughput as well as
meeting PU interruption constraints in a wide range of parameter settings.


title: Three-body final state interaction in $\eta \to 3 \pi$ updated

abstract:
  In view of the recent high-statistic KLOE data for the $\eta \to \pi^+ \pi^-
\pi^0$ decay, a new determination of the quark mass double ratio has been done.
Our approach relies on a dispersive model that takes into account rescattering
effects between three pions via subenergy unitarity. The latter is essential to
reproduce the Dalitz plot distribution. A simultaneous description of the KLOE
and WASA-at-COSY data is achieved in terms of just two real parameters. From a
global fit, we determine $Q=21.6 \pm 1.1$. The predicted slope parameter for
the neutral channel $\alpha=-0.025\pm 0.004$ is in reasonable agreement with
the PDG average value.


title:
Word Segmentation on Micro-blog Texts with External Lexicon and
  Heterogeneous Data

abstract:
  This paper describes our system designed for the NLPCC 2016 shared task on
word segmentation on micro-blog texts.


title:
Dispersion degeneracies and standing modes in flexural waves supported
  by Rayleigh beam structures

abstract:
  The paper presents a novel analysis of Floquet-Bloch flexural waves in a
periodic lattice-like structure consisting of flexural beam ligaments. A
special feature of this structure is in the presence of the rotational inertia,
which is commonly neglected in conventional models of the Euler-Bernoulli type.
The dispersion properties of the Rayleigh beam structure with rotational
inertia include degeneracies linked to Dirac cones on the dispersion diagrams
as well as directional anisotropy and special refraction properties. Steering
of Dirac cones is described for rectangular flexural structures with a
rotational inertia. Numerical examples for a forced network of Rayleigh and
Euler-Bernoulli beams illustrate directional localisation, negative refraction,
localisation at an interface and neutrality for propagating plane waves across
a structured interface for a frequency range corresponding to a Dirac cone.


title:
Loss-based Experimental Test of Bohr's Complementarity Principle with
  Single Neutral Atom

abstract:
  An experimental test of quantum complementarity principle based on single
neutral atom trapped in a blue detuned bottle trap was here performed. A Ramsey
interferometer was used to assess the wavelike behavior or particle-like
behavior with second $\pi/2$-rotation on or off. The wavelike behavior or
particle-like behavior is characterized by the visibility $V$ of the
interference or the predictability $P$ of which-path information, respectively.
The measured results fulfill the complementarity relation $P^2+V^2\leq1$.
Imbalance losses were deliberately introduced to the stem and find the
complementarity relation is then formally "violated." All the experimental
results can be completely explained theoretically by quantum mechanics without
considering the interference between wave and particle behaviors. This
observation complements existing information concerning the BCP based on
wave-particle duality of massive quantum.


title: Viscous propulsion in active transversely-isotropic media

abstract:
  Taylor's swimming sheet is a classical model of microscale propulsion and
pumping. Many biological fluids and substances are fibrous, having a preferred
direction in their microstructure; for example cervical mucus is formed of
polymer molecules which create an oriented fibrous network. Moreover,
suspensions of elongated motile cells produce a form of active oriented matter.
To understand how these effects modify viscous propulsion, we extend Taylor's
classical model of small-amplitude zero-Reynolds-number propulsion of a
'swimming sheet' via the transversely-isotropic fluid model of Ericksen, which
is linear in strain rate and possesses a distinguished direction. The energetic
costs of swimming are significantly altered by all rheological parameters and
the initial fibre angle. Propulsion in a passive transversely-isotropic fluid
produces an enhanced mean rate of working, independent of the initial fibre
orientation, with an approximately linear dependence of energetic cost on the
extensional and shear enhancements to the viscosity caused by fibres. In this
regime the mean swimming velocity is unchanged from the Newtonian case. The
effect of the constant term in Ericksen's model for the stress, which can be
identified as a fibre tension or alternatively a stresslet characterising an
active fluid, is also considered. This stress introduces an angular dependence
and dramatically changes the streamlines and flow field; fibres aligned with
the swimming direction increase the energetic demands of the sheet. The
constant fibre stress may result in a reversal of the mean swimming velocity
and a negative mean rate of working if sufficiently large relative to the other
rheological parameters.


title: Weight-Lattice Discretization of Weyl-Orbit Functions

abstract:
  Weyl-orbit functions have been defined for each simple Lie algebra, and
permit Fourier-like analysis on the fundamental region of the corresponding
affine Weyl group. They have also been discretized, using a refinement of the
coweight lattice, so that digitized data on the fundamental region can be
Fourier-analyzed. The discretized orbit function has arguments that are
redundant if related by the affine Weyl group, while its labels, the Weyl-orbit
representatives, invoke the dual affine Weyl group. Here we discretize the
orbit functions in a novel way, by using the weight lattice. A cleaner theory
results, with symmetry between the arguments and labels of the discretized
orbit functions. Orthogonality of the new discretized orbit functions is
proved, and leads to the construction of unitary, symmetric matrices with
Weyl-orbit-valued elements. For one type of orbit function, the matrix
coincides with the Kac-Peterson modular $S$ matrix, important for
Wess-Zumino-Novikov-Witten conformal field theory.


title: Riesz bases generated by the spectra of Sturm-Liouville problems

abstract:
  Let $\{\lambda_n^2\}_{n = 0}^\infty$ be the spectra of a Sturm-Liouville
problem on $[0,\pi ]$. We investigate the question: Do the systems
$\{\cos(\lambda_n x)\}_{n= 0}^\infty$ or $\{\sin(\lambda_n x)\}_{n = 0}^\infty$
form Riesz bases in ${L^2}[0,\pi]$? The answer is almost always positive.


title: Pion light-by-light contributions to the muon $g-2$

abstract:
  This paper contains some new results on the hadronic light-by-light
contribution (HLbL) to the muon $g-2$. The first part argues that we can expect
large effects from disconnected diagrams in present and future calculations by
lattice QCD of HLbL. The argument is based on the dominance of pseudo-scalar
meson exchange.
  In the second part, we revisit the pion loop HLbL contribution to the muon
anomalous magnetic moment. We study it in the framework of some models studied
earlier, pure pion loop, full VMD and hidden local symmetry for inclusion of
vector mesons. In addition we study possible ways to include the axial-vector
meson. The main part of the work is a detailed study of how the different
momentum regions contribute. We derive a short distance constraint on the
$\gamma^*\gamma^*\to\pi\pi$ amplitude and use this as a constraint on the
models used for the pion loop. As a byproduct we present the general result for
integration using the Gegenbauer polynomial method.


title:
Using Approximate Bayesian Computation by Subset Simulation for
  Efficient Posterior Assessment of Dynamic State-Space Model Classes

abstract:
  Approximate Bayesian Computation (ABC) methods have gained in their
popularity over the last decade because they expand the horizon of Bayesian
parameter inference methods to the range of models for which only forward
simulation is available. The majority of the ABC methods rely on the choice of
a set of summary statistics to reduce the dimension of the data. However, as
has been noted in the ABC literature, the lack of convergence guarantees that
is induced by the absence of a vector of sufficient summary statistics that
assures inter-model sufficiency over the set of competing models, hinders the
use of the usual ABC methods when applied to Bayesian model selection or
assessment. In this paper, we present a novel ABC model selection procedure for
dynamical systems based on a newly appeared multi-level Markov chain Monte
Carlo method, self-regulating ABC-SubSim, and a hierarchical state-space
formulation of dynamic models. We show that this formulation makes it possible
to independently approximate the model evidence required for assessing the
posterior probability of each of the competing models. We also show that
ABC-SubSim not only provides an estimate of the model evidence as a simple
by-product but also it gives the posterior probability of each model as a
function of the tolerance level, which allows the ABC model choices made in
previous studies to be understood. We illustrate the performance of the
proposed framework for ABC model updating and model class selection by applying
it to two problems in Bayesian system identification: a single
degree-of-freedom bilinear hysteretic oscillator and a three-story shear
building with Masing hysteresis, both of which are subject to a seismic
excitation.


title: Statistics of Quantum Turbulence in Superfluid He

abstract:
  Based on our current understanding of statistics of quantum turbulence as
well as on results of intensive ongoing analytical, numerical and experimental
studies we overview here the following problems in the large-scale,
space-homogeneous, steady-state turbulence of superfluid $^4$He and $^3$He: 1)
Energy spectra of normal and superfluid velocity components; 2)
Cross-correlation function of normal and superfluid velocities; 3) Energy
dissipation by mutual friction and viscosity; 4) Energy exchange between normal
and superfluid components; 5) High-order statistics and intermittency effects.
The statistical properties are discussed for turbulence in different types of
flows: coflow of $^4$He; turbulent $^3$He with the laminar normal fluid; pure
superflow and counterflow in He-4.


title: Stellar photometry with Multi Conjugate Adaptive Optics

abstract:
  We overview the current status of photometric analyses of images collected
with Multi Conjugate Adaptive Optics (MCAO) at 8-10m class telescopes that
operated, or are operating, on sky. Particular attention will be payed to
resolved stellar population studies. Stars in crowded stellar systems, such as
globular clusters or in nearby galaxies, are ideal test particles to test AO
performance. We will focus the discussion on photometric precision and accuracy
reached nowadays. We briefly describe our project on stellar photometry and
astrometry of Galactic globular clusters using images taken with GeMS at the
Gemini South telescope. We also present the photometry performed with DAOPHOT
suite of programs into the crowded regions of these globulars reaching very
faint limiting magnitudes Ks ~21.5 mag on moderately large fields of view (~1.5
arcmin squared). We highlight the need for new algorithms to improve the
modeling of the complex variation of the Point Spread Function across the field
of view. Finally, we outline the role that large samples of stellar standards
plays in providing a detailed description of the MCAO performance and in
precise and accurate colour{magnitude diagrams.


title: Existence of the passage to the limit of inviscid fluid

abstract:
  In the dynamics of viscous fluid, the case of vanishing kinematic viscosity
is actually equivalent to the Reynolds number tending to infinity. Hence, in
the limit of vanishing viscosity the fluid flow is essentially turbulent. On
the other hand, the Euler equation, which is conventionally adopted for
description of flow of inviscid fluid, does not possess proper turbulent
behaviour. This raises the question of the existence of the passage to the
limit of inviscid fluid for real low-viscosity fluids. To address this
question, one should employ the theory of turbulent boundary layer near an
inflexible boundary (e.g., rigid wall). On the basis of this theory, one can
see how the solutions to the Euler equation become relevant for the description
of flow of low-viscosity fluids, and obtain the small parameter quantifying
accuracy of this description for real fluids.


title: On the constructive solution of an inverse Sturm-Liouville problem

abstract:
  The necessary and sufficient conditions are found for the two sequences
$\left\{\mu_n \right\}_{n=0}^{\infty}$ and $\left\{a_n \right\}_{n=0}^{\infty}$
to be the spectrum and the norming constants respectively, for a boundary value
problem $-y'' + q \left( x \right) y = \mu y,$ $y \left(0\right)=0,$ $y\left(
\pi \right)\cos \beta + y'\left( \pi \right)\sin \beta = 0,$ $\beta \in \left(
0, \pi \right),$ with $q \in L_{\mathbb{R}}^1 \left[0, \pi \right].$


title: Decaying turbulence for the fractional subcritical Burgers equation

abstract:
  We consider the fractional unforced Burgers equation in the one-dimensional
space-periodic setting: $$\partial u/\partial t+(f(u))_x +\nu \Lambda^{\alpha}
u= 0, t \geq 0,\ \mathbb{x} \in \mathbb{T}^d=(\mathbb{R}/\mathbb{Z})^d.$$ Here
$f$ is strongly convex and satisfies an additional growth condition,
$\Lambda=\sqrt{-\Delta}$, $\nu$ is small and positive, while $\alpha \in (1,\
2)$ is a constant in the subcritical range.
  For solutions $u$ of this equation, we generalise the results obtained for
the case $\alpha=2$ (i.e. when $-\Lambda^{\alpha}$ is the Laplacian) in [10].
We obtain sharp estimates for the time-averaged Sobolev norms of $u$ as a
function of $\nu$. These results yield sharp estimates for natural analogues of
quantities characterising the hydrodynamical turbulence, namely the averages of
the increments and of the energy spectrum. In the inertial range, these
quantities behave as a power of the norm of the relevant parameter, which is
respectively the separation $\ell$ in the physical space and the wavenumber
$\mathbf{k}$ in the Fourier space.
  The form of all estimates is the same as in the case $\alpha=2$; the only
thing that changes (except implicit constants) is that $\nu$ is replaced by
$\nu^{1/(\alpha-1)}$.


title: Airy-type evolution equations on star graphs

abstract:
  In the present paper the Airy operator on star graphs is defined and studied.
The Airy operator is a third order differential operator arising in different
contexts, but our main concern is related to its role as the linear part of the
Korteweg-de Vries equation, usually studied on a line or a half-line. The first
problem treated and solved is its correct definition, with different
characterizations, as a skew-adjoint operator on a star graph, a set of lines
connecting at a common vertex representing, for example, a network of branching
channels. A necessary condition turns out to be that the graph is balanced,
i.e. there is the same number of ingoing and outgoing edges at the vertex. The
simplest example is that of the line with a point interaction at the vertex. In
these cases the Airy dynamics is given by a unitary or isometric (in the real
case) group. In particular the analysis provides the complete classification of
boundary conditions giving momentum (i.e., $L^2$-norm of the solution)
preserving evolution on the graph. A second more general problem here solved is
the characterization of conditions under which the Airy operator generates a
contraction semigroup. In this case unbalanced star graphs are allowed. In both
unitary and contraction dynamics, restrictions on admissible boundary
conditions occur if conservation of mass (i.e., integral of the solution) is
further imposed. The above well posedness results can be considered preliminary
to the analysis of nonlinear wave propagation on branching structures.


title:
Resonances and multistability in a Josephson junction connected to a
  resonator

abstract:
  We study the dynamics of a Josephson junction connected to a dc current
supply via a distributed parameter capacitor, which serves as a resonator. We
reveal multistability in the current-voltage characteristic of the system; this
multistability is related to resonances between the generated frequency and the
resonator. The resonant pattern requires detailed consideration, in particular,
because its basic features may resemble those of patterns reported in
experiments with arrays of Josephson junctions demonstrating coherent
stimulated emission. From the viewpoint of nonlinear dynamics, the resonances
between a Josephson junction and a resonator are of interest because of
specificity of the former; its oscillation frequency is directly governed by
control parameters of the system and can vary in a wide range. Our analytical
results are in good agreement with the results of numerical simulations.


title: Linear-time Kernelization for Feedback Vertex Set

abstract:
  In this paper, we propose an algorithm that, given an undirected graph $G$ of
$m$ edges and an integer $k$, computes a graph $G'$ and an integer $k'$ in
$O(k^4 m)$ time such that (1) the size of the graph $G'$ is $O(k^2)$, (2)
$k'\leq k$, and (3) $G$ has a feedback vertex set of size at most $k$ if and
only if $G'$ has a feedback vertex set of size at most $k'$. This is the first
linear-time polynomial-size kernel for Feedback Vertex Set. The size of our
kernel is $2k^2+k$ vertices and $4k^2$ edges, which is smaller than the
previous best of $4k^2$ vertices and $8k^2$ edges. Thus, we improve the size
and the running time simultaneously. We note that under the assumption of
$\mathrm{NP}\not\subseteq\mathrm{coNP}/\mathrm{poly}$, Feedback Vertex Set does
not admit an $O(k^{2-\epsilon})$-size kernel for any $\epsilon>0$.
  Our kernel exploits $k$-submodular relaxation, which is a recently developed
technique for obtaining efficient FPT algorithms for various problems. The dual
of $k$-submodular relaxation of Feedback Vertex Set can be seen as a
half-integral variant of $A$-path packing, and to obtain the linear-time
complexity, we propose an efficient augmenting-path algorithm for this problem.
We believe that this combinatorial algorithm is of independent interest.
  A solver based on the proposed method won first place in the 1st
Parameterized Algorithms and Computational Experiments (PACE) challenge.


title: An Exact Enumeration of Distance-Hereditary Graphs

abstract:
  Distance-hereditary graphs form an important class of graphs, from the
theoretical point of view, due to the fact that they are the totally
decomposable graphs for the split-decomposition. The previous best enumerative
result for these graphs is from Nakano et al. (J. Comp. Sci. Tech., 2007), who
have proven that the number of distance-hereditary graphs on $n$ vertices is
bounded by ${2^{\lceil 3.59n\rceil}}$.
  In this paper, using classical tools of enumerative combinatorics, we improve
on this result by providing an exact enumeration of distance-hereditary graphs,
which allows to show that the number of distance-hereditary graphs on $n$
vertices is tightly bounded by ${(7.24975\ldots)^n}$---opening the perspective
such graphs could be encoded on $3n$ bits. We also provide the exact
enumeration and asymptotics of an important subclass, the 3-leaf power graphs.
  Our work illustrates the power of revisiting graph decomposition results
through the framework of analytic combinatorics.


title:
Enumerations, Forbidden Subgraph Characterizations, and the
  Split-Decomposition

abstract:
  Forbidden characterizations may sometimes be the most natural way to describe
families of graphs, and yet these characterizations are usually very hard to
exploit for enumerative purposes.
  By building on the work of Gioan and Paul (2012) and Chauve et al. (2014), we
show a methodology by which we constrain a split-decomposition tree to avoid
certain patterns, thereby avoiding the corresponding induced subgraphs in the
original graph.
  We thus provide the grammars and full enumeration for a wide set of graph
classes: ptolemaic, block, and variants of cactus graphs (2,3-cacti, 3-cacti
and 4-cacti). In certain cases, no enumeration was known (ptolemaic, 4-cacti);
in other cases, although the enumerations were known, an abundant potential is
unlocked by the grammars we provide (in terms of asymptotic analysis, random
generation, and parameter analyses, etc.).
  We believe this methodology here shows its potential; the natural next step
to develop its reach would be to study split-decomposition trees which contain
certain prime nodes. This will be the object of future work.


title: Applicability of Effective Pair Potentials for Active Brownian Particles

abstract:
  We have performed a case study investigating a recently proposed scheme to
obtain an effective pair potential for active Brownian particles [Farage et
al., Phys. Rev. E 91, 042310 (2015)]. Applying this scheme to the Lennard-Jones
potential, numerical simulations of active Brownian particles are compared to
simulations of passive Brownian particles interacting by the effective pair
potential. Analyzing the static pair correlations, our results indicate a
limited range of activity parameters (speed and orientational correlation time)
for which we obtain quantitative, or even qualitative, agreement. Moreover, we
find a qualitatively different behavior for the virial pressure even for small
propulsion speeds. Combining these findings we conclude that beyond linear
response active particles exhibit genuine non-equilibrium properties that
cannot be captured by effective pair interaction alone.


title:
Large Deviations and Sum Rules for Spectral Theory - A Pedagogical
  Approach

abstract:
  This is a pedagogical exposition of the large deviation approach to sum rules
pioneered by Gamboa, Nagel and Rouault. We'll explain how to use their ideas to
recover the Szeg}o and Killip{ Simon Theorems. The primary audience is spectral
theorists and people working on orthogonal polynomials who have limited
familiarity with the theory of large deviations.


title: Security Monitoring of the Cyber Space

abstract:
  Adversaries are abusing Internet security and privacy services to execute
cyber attacks. To cope with these threats, network operators utilize various
security tools and techniques to monitor the cyber space. An efficient way to
infer Internet threat activities is to collect information from trap-based
monitoring sensors. As such, this chapter primarily defines the cyberspace
trap-based monitoring systems and their taxonomies. Moreover, it presents the
state-of-the-art in terms of research contributions and techniques, tools and
technologies. Furthermore, it identifies gaps in terms of science and
technology. Additionally, it presents some case studies and practical
approaches corresponding to large-scale cyber monitoring systems such as
Nicter. We further present some related security policies and legal issues for
network monitoring. This chapter provides an overview on Internet monitoring
and offers a guideline for readers to help them understand the concepts of
observing, detecting and analyzing cyber attacks through computer network
traps.


title: Temperature of a single chaotic eigenstate

abstract:
  The onset of thermalization in a closed finite system of randomly interacting
bosons, at the level of a single eigenstate, is discussed. The main interest is
in the emergence of the Bose-Einstein distribution of single-particle
occupation numbers, establishing a global and local criterion for
thermalization. We show how to define the temperature of a given eigenstate,
provided that it has a chaotic structure in the basis defined by
single-particle states. The analytical expression for the eigenstate
temperature as a function of the inter-particle interaction and energy is
complemented by numerical data.


title:
Bulk Superconductivity Induced by In-plane Chemical Pressure Effect in
  Eu0.5La0.5FBiS2-xSex

abstract:
  We have investigated Se substitution effect to superconductivity of an
optimally-doped BiS2-based superconductor Eu0.5La0.5FBiS2. Eu0.5La0.5FBiS2-xSex
samples with x = 0-1 were synthesized. With increasing x, in-plane chemical
pressure is enhanced. For x = 0.6, 0.8, and 1, superconducting transitions with
a large shielding volume fraction are observed in magnetic susceptibility
measurements, and the highest Tc is 3.8 K for x = 0.8. From low-temperature
electrical resistivity measurements, a zero-resistivity state is observed for
all the samples, and the highest Tc is observed for x = 0.8. With increasing Se
concentration, characteristics of electrical resistivity changes from
semiconducting-like to metallic, suggesting that the emergence of bulk
superconductivity is linked with the enhanced metallicity. A superconductivity
phase diagram of the Eu0.5La0.5FBiS2-xSex superconductor is established.
Temperature dependences of electrical resistivity show an anomalous two-step
transition under high magnetic fields. Hence, the resistivity data are analyzed
with assuming in-plane anisotropy of upper critical field.


title: UnitBox: An Advanced Object Detection Network

abstract:
  In present object detection systems, the deep convolutional neural networks
(CNNs) are utilized to predict bounding boxes of object candidates, and have
gained performance advantages over the traditional region proposal methods.
However, existing deep CNN methods assume the object bounds to be four
independent variables, which could be regressed by the $\ell_2$ loss
separately. Such an oversimplified assumption is contrary to the well-received
observation, that those variables are correlated, resulting to less accurate
localization. To address the issue, we firstly introduce a novel Intersection
over Union ($IoU$) loss function for bounding box prediction, which regresses
the four bounds of a predicted box as a whole unit. By taking the advantages of
$IoU$ loss and deep fully convolutional networks, the UnitBox is introduced,
which performs accurate and efficient localization, shows robust to objects of
varied shapes and scales, and converges fast. We apply UnitBox on face
detection task and achieve the best performance among all published methods on
the FDDB benchmark.


title: Tensor Modes Damping in Matter and Vacuum Dominated Era

abstract:
  The present paper has developed an integro-differential equation to propagate
cosmological gravitation waves in matter-dominated era in accounting for the
presence of free streaming neutrinos as a traceless transverse tensor part of
the anisotropic stress tensor. Its focus is on short and long wavelengths of
GWs that enter the horizon in matter-dominated era. Results show that the
anisotropic stress reduces the squared amplitude by $ 0.03\%$ for wavelengths,
entering the horizon during matter-dominated phase. This reduction is less for
those wavelengths that enter the horizon at $ \Lambda $ dominated era in flat
spacetime. All of the calculations have been done in closed spacetime and the
results have been compared with the radiation-dominated case for both flat and
closed spacetimes. Finally the paper investigates the effect of closed
background on the amplitude of the gravitational waves.


title:
Ultraslow water-mediated transmembrane interactions regulate the
  activation of A$_{\text{2A}}$ adenosine receptor

abstract:
  Water molecules inside G-protein coupled receptor have recently been
spotlighted in a series of crystal structures. To decipher the dynamics and
functional roles of internal waters in GPCR activity, we studied
A$_{\text{2A}}$ adenosine receptor using $\mu$sec-molecular dynamics
simulations. Our study finds that the amount of water flux across the
transmembrane (TM) domain varies depending on the receptor state, and that the
water molecules of the TM channel in the active state flow three times slower
than those in the inactive state. Depending on the location in solvent-protein
interface as well as the receptor state, the average residence time of water in
each residue varies from $\sim\mathcal{O}(10^2)$ psec to
$\sim\mathcal{O}(10^2)$ nsec. Especially, water molecules, exhibiting ultraslow
relaxation ($\sim\mathcal{O}(10^2)$ nsec) in the active state, are found around
the microswitch residues that are considered activity hotspots for GPCR
function. A continuous allosteric network spanning the TM domain, arising from
water-mediated contacts, is unique in the active state, underscoring the
importance of slow waters in the GPCR activation.


title:
Pinning Susceptibility : A Novel Method to Study Growth of Amorphous
  Order in Glass-forming Liquids

abstract:
  Existence and growth of amorphous order in supercooled liquids approaching
glass transition is a subject of intense research. Even after decades of work,
there is still no clear consensus on the molecular mechanisms that lead to a
rapid slowing down of liquid dynamics approaching this putative transition. The
existence of a correlation length associated with amorphous order has recently
been postulated and also been estimated using multi-point correlation functions
which cannot be calculated easily in experiments. Thus the study of growing
amorphous order remains mostly restricted to systems like colloidal glasses and
simulations of model glass-forming liquids. In this Letter, we propose an
experimentally realizable yet simple correlation function to study the growth
of amorphous order. We then demonstrate the validity of this approach for a few
well-studied model supercooled liquids and obtain results which are consistent
with other conventional methods.


title:
Doping induced spin state transition in Li$_x$CoO$_2$ as studied by the
  GGA+DMFT calculations

abstract:
  Magnetic properties of Li$_x$CoO$_2$ for $x = 0.94, 0.75, 0.66$ and $0.51$
were investigated in frames of method combining Generalized Gradient
Approximation with Dynamical Mean--Field Theory (GGA+DMFT). We found that a
delicate interplay between Hund's exchange energy and $t_{2g}-e_g$ crystal
field splitting is responsible for the high spin to low spin state transition
for Co$^{4+}$ ions. The GGA+DMFT calculations show that at small doping level
the Co$^{4+}$ ions adopt high spin state, while delithiation results in
increase of the crystal field splitting and low spin state becomes preferable.
The Co$^{3+}$ ions were found to stays in the low spin configuration for any
$x$.


title: Radiation effects on the Gaia CCDs after 30 months at L2

abstract:
  Since the launch of ESA's Gaia satellite in December 2013, the 106
large-format scientific CCDs onboard have been operating at L2. Due to a
combination of the high-precision measurement requirements of the mission and
the predicted proton environment at L2, the effect of non-ionizing radiation
damage on the detectors was early identified pre-launch as potentially imposing
a major limitation on the scientific value of the data. In this paper we
compare pre-flight radiation-induced Charge Transfer Inefficiency (CTI)
predictions against in-flight measurements, focusing especially on charge
injection diagnostics, as well as correlating these CTI diagnostic results with
solar proton event data. We show that L2-directed solar activity has been
relatively low since launch, and radiation damage (so far) is less than
originally expected. Despite this, there are clear cases of correlation between
earth-directed solar coronal mass ejection events and abrupt changes in CTI
diagnostics over time. These sudden jumps are lying on top of a rather constant
increase in CTI which we show is primarily due to the continuous bombardment of
the devices by high-energy Galactic Cosmic Rays. We examine the possible
reasons for the lower than expected levels of CTI as well as examining the
effect of controlled payload heating events on the CTI diagnostics.
Radiation-induced CTI in the CCD serial registers and effects of ionizing
radiation are also correspondingly lower than expected, however these topics
are not examined here in detail.


title:
Heteronuclear Efimov scenario with positive intraspecies scattering
  length

abstract:
  We investigate theoretically and experimentally the heteronuclear Efimov
scenario for a three-body system that consists of two bosons and one
distinguishable particle with positive intraspecies scattering lengths. The
three-body parameter at the three-body scattering threshold and the scaling
factor between consecutive Efimov resonances are found to be controlled by the
scattering length between the two bosons, approximately independent of
short-range physics. We observe two excited-state Efimov resonances in the
three-body recombination spectra of an ultracold mixture of fermionic $^6 $Li
and bosonic $^{133} $Cs atoms close to a Li-Cs Feshbach resonance, where the
Cs-Cs interaction is positive. Deviation of the obtained scaling factor of
4.0(3) from the universal prediction of 4.9 and the absence of the ground state
Efimov resonance shed new light on the interpretation of the universality and
the discrete scaling behavior of heteronuclear Efimov physics.

categories: cond-mat.quant-gas nucl-th physics.atom-ph quant-ph


title:
Search for the suppressed decays $B^{+}\rightarrow K^{+}K^{+}\pi^{-}$
  and $B^{+}\rightarrow \pi^{+}\pi^{+}K^{-}$

abstract:
  A search is made for the highly-suppressed B meson decays $B^{+}\rightarrow
K^{+}K^{+}\pi^{-}$ and $B^{+}\rightarrow \pi^{+}\pi^{+}K^{-}$ using a data
sample corresponding to an integrated luminosity of 3.0 $fb^{-1}$ collected by
the LHCb experiment in proton-proton collisions at centre-of-mass energies of 7
and 8 TeV. No evidence is found for the decays, and upper limits at 90\%
confidence level are determined to be $\mathcal{B}(B^{+}\rightarrow
K^{+}K^{+}\pi^{-}) < 1.1\times 10^{-8}$ and $\mathcal{B}(B^{+}\rightarrow
\pi^{+}\pi^{+}K^{-}) < 4.6\times 10^{-8}$.


title:
Precise determination of the 1s Lamb Shift in hydrogen-like lead and
  gold ions using microcalorimeters

abstract:
  Quantum electrodynamics in very strong Coulomb fields is one scope which has
not yet been tested experimentally with suffcient accuracy to really determine
whether the perturbative approach is valid. One sensitive test is the
determination of the 1s Lamb Shift in highly-charged very heavy ions. The 1s
Lamb Shift of hydrogen-like lead (Pb81+) and gold (Au78+) has been determined
using the novel detector concept of silicon microcalorimeters for the detection
of hard X-rays. The results of (260 +- 22) eV for lead and (208 +- 13) eV for
gold are within error bars in good agreement with theoretical predictions. For
hydrogen-like lead, this represents the most accurate determination of the 1s
Lamb Shift to our knowledge.


title:
Correlation functions in resonance fluorescence with spectral
  resolution: Signal-processing approach

abstract:
  In the framework of the signal processing approach to single-atom resonance
fluorescence with spectral resolution, we diagrammatically derive an analytical
formula for arbitrary-order spectral correlation functions of the scattered
fields that pass through Fabry-Perot interferometers. Our general expression is
then applied to study correlation signals in the limit of well separated
spectral lines of the resonance fluorescence spectrum. In particular, we study
the normalized second-order temporal intensity correlation functions in the
case of the interferometers tuned to the components of the spectrum and obtain
interferential corrections to the approximate results derived in the secular
limit. In addition, we explore purely spectral correlations and show that they
can fully be understood in terms of the two-photon cascades down the dressed
state ladder.


title:
Synthetic gauge field and pseudospin-orbit interaction in a stacked
  two-dimensional ring-network lattice

abstract:
  We study the effects of a synthetic gauge field and pseudospin-orbit
interaction in a stacked two-dimensional ring-network model. The model was
introduced to simulate light propagation in the corresponding ring-resonator
lattice, and is thus completely bosonic. Without these two items, the model
exhibits Floquet-Weyl and Floquet-topological-insulator phases with
topologically gapless and gapped band structures, respectively. The synthetic
magnetic field implemented in the model results in a three-dimensional
Hofstadter-butterfly-type spectrum in a photonic platform. The resulting gaps
are characterization by the winding number of relevant S-matrices together with
the Chern number of the bulk bands. The pseudospin-orbit interaction is defined
as the mixing term between two pseudospin degrees of freedom in the rings,
namely, the clockwise and counter-clockwise modes. It destroys the
Floquet-topological-insulator phases, while the Floquet-Weyl phase with
multiple Weyl points can be preserved by breaking the space-inversion symmetry.
Implementing both the synthetic gauge field and pseudospin-orbit interaction
requires a certain nonreciprocity.


title: Derived coisotropic structures I: affine case

abstract:
  We define and study coisotropic structures on morphisms of commutative dg
algebras in the context of shifted Poisson geometry, i.e. $P_n$-algebras.
Roughly speaking, a coisotropic morphism is given by a $P_{n+1}$-algebra acting
on a $P_n$-algebra. One of our main results is an identification of the space
of such coisotropic structures with the space of Maurer--Cartan elements in a
certain dg Lie algebra of relative polyvector fields. To achieve this goal, we
construct a cofibrant replacement of the operad controlling coisotropic
morphisms by analogy with the Swiss-cheese operad which can be of independent
interest. Finally, we show that morphisms of shifted Poisson algebras are
identified with coisotropic structures on their graph.


title:
Deformation-induced splitting of isoscalar E0 giant resonance: Skyrme
  random-phase-approximation analysis

abstract:
  The deformation-induced splitting of isoscalar giant monopole resonance
(ISGMR) is systematically analyzed in a wide range of masses covering medium,
rare-earth, actinide, and superheavy axial deformed nuclei. The study is
performed within the fully self-consistent quasiparticle
random-phase-approximation (QRPA) method based on the Skyrme functional. Two
Skyrme forces, one with a large (SV-bas) and one with a small (SkP) nuclear
incompressibility, are considered. The calculations confirm earlier results
that, due to the deformation-induced E0-E2 coupling, the isoscalar E0 resonance
attains a double-peak structure and significant energy upshift. Our results are
compared with available analytic estimations. Unlike earlier studies, we get a
smaller energy difference between the lower and upper peaks and thus a stronger
E0-E2 coupling. This in turn results in more pumping of E0 strength into the
lower peak and more pronounced splitting of ISGMR. We also discuss widths of
the peaks and their negligible correlation with deformation.


title:
Measurement of forward $W\to e\nu$ production in $pp$ collisions at
  $\sqrt{s}=8\,$TeV

abstract:
  A measurement of the cross-section for $W \to e\nu$ production in $pp$
collisions is presented using data corresponding to an integrated luminosity of
$2\,$fb$^{-1}$ collected by the LHCb experiment at a centre-of-mass energy of
$\sqrt{s}=8\,$TeV. The electrons are required to have more than $20\,$GeV of
transverse momentum and to lie between 2.00 and 4.25 in pseudorapidity. The
inclusive $W$ production cross-sections, where the $W$ decays to $e\nu$, are
measured to be \begin{equation*} \sigma_{W^{+} \to e^{+}\nu_{e}}=1124.4\pm
2.1\pm 21.5\pm 11.2\pm 13.0\,\mathrm{pb}, \end{equation*} \begin{equation*}
\sigma_{W^{-} \to e^{-}\bar{\nu}_{e}}=\,\,\,809.0\pm 1.9\pm 18.1\pm\,\,\,7.0\pm
\phantom{0}9.4\,\mathrm{pb}, \end{equation*} where the first uncertainties are
statistical, the second are systematic, the third are due to the knowledge of
the LHC beam energy and the fourth are due to the luminosity determination.
Differential cross-sections as a function of the electron pseudorapidity are
measured. The $W^{+}/W^{-}$ cross-section ratio and production charge asymmetry
are also reported. Results are compared with theoretical predictions at
next-to-next-to-leading order in perturbative quantum chromodynamics. Finally,
in a precise test of lepton universality, the ratio of $W$ boson branching
fractions is determined to be \begin{equation*} \mathcal{B}(W \to
e\nu)/\mathcal{B}(W \to \mu\nu)=1.020\pm 0.002\pm 0.019, \end{equation*} where
the first uncertainty is statistical and the second is systematic.


title:
Beam tests of an integrated prototype of the ATLAS Forward Proton
  detector

abstract:
  The ATLAS Forward Proton (AFP) detector is intended to measure protons
scattered at small angles from the ATLAS interaction point. To this end, a
combination of 3D Silicon pixel tracking modules and Quartz-Cherenkov
time-of-flight (ToF) detectors is installed 210m away from the interaction
point at both sides of ATLAS. Beam tests with an AFP prototype detector
combining tracking and timing sub-detectors and a common readout have been
performed at the CERN-SPS test-beam facility in November 2014 and September
2015 to complete the system integration and to study the detector performance.
The successful tracking-timing integration was demonstrated. Good tracker hit
efficiencies above 99.9% at a sensor tilt of 14{\deg}, as foreseen for AFP,
were observed. Spatial resolutions in the short pixel direction with 50 {\mu}m
pitch of 5.5 +/- 0.5 {\mu}m per pixel plane and of 2.8 +/- 0.5 {\mu}m for the
full four-plane tracker at 14{\deg} were found, largely surpassing the AFP
requirement of 10 {\mu}m. The timing detector showed also good hit efficiencies
above 99%, and a full-system time resolution of 35 +/- 6 ps was found for the
ToF prototype detector with two Quartz bars in-line (half the final AFP size)
without dedicated optimisation, fulfilling the requirements for initial
low-luminosity AFP runs.


title:
Closed-form expression for the magnetic shielding constant of the
  relativistic hydrogenlike atom in an arbitrary discrete energy eigenstate:
  Application of the Sturmian expansion of the generalized Dirac-Coulomb Green
  function

abstract:
  We present analytical derivation of the closed-form expression for the dipole
magnetic shielding constant of a Dirac one-electron atom being in an arbitrary
discrete energy eigenstate. The external magnetic field, by which the atomic
state is perturbed, is assumed to be weak, uniform and time independent. With
respect to the atomic nucleus we assume that it is pointlike, spinless,
motionless and of charge Ze. Calculations are based on the Sturmian expansion
of the generalized Dirac- Coulomb Green function [R. Szmytkowski, J. Phys. B
30, 825 (1997); erratum 30, 2747 (1997)], combined with the theory of
hypergeometric functions. The final result is of an elementary form and agrees
with corresponding formulas obtained earlier by other authors for some
particular states of the atom.


title: Streaming Weighted Matchings: Optimal Meets Greedy

abstract:
  We consider the problem of approximating a maximum weighted matching, when
the edges of an underlying weighted graph $G(V,E)$ are revealed in a streaming
fashion. We analyze a variant of the previously best-known
$(4+\epsilon)$-approximation algorithm due to Crouch and Stubbs (APPROX, 2014),
and prove their conjecture that it achieves a tight approximation factor of
$3.5+\epsilon$.
  The algorithm splits the stream into substreams on which it runs a greedy
maximum matching algorithm. At the end of the stream, the selected edges are
given as input to an optimal maximum weighted matching algorithm. To analyze
the approximation guarantee, we develop a novel charging argument in which we
decompose the edges of a maximum weighted matching of $G$ into a few natural
classes, and then charge them separately to the edges of the matching output by
our algorithm.


title:
The 2-surviving rate of planar graphs with average degree lower than
  $4\frac{1}{2}$

abstract:
  Let $G$ be any connected graph on $n$ vertices, $n \ge 2.$ Let $k$ be any
positive integer. Suppose that a fire breaks out at some vertex of $G.$ Then,
in each turn firefighters can protect at most $k$ vertices of $G$ not yet on
fire; Next the fire spreads to all unprotected neighbours. The $k$-surviving
rate of G, denoted by $\rho_k(G),$ is the expected fraction of vertices that
can be saved from the fire, provided that the starting vertex is chosen
uniformly at random.
  In this note, it is shown that for any planar graph $G$ with average degree
$4\frac{1}{2} - \epsilon,$ where $\epsilon \in (0, 1],$ we have $\rho_2(G) \ge
\frac{2}{9}\epsilon$. In particular, the result implies a significant
improvement of the bound for 2-surviving rate for triangle-free planar graphs
(Esperet, van den Heuvel, Maffray and Sipma, 2013) and for planar graphs
without 4-cycles (Kong, Wang, Zhang, 2012). The proof is done using the
separator theorem for planar graphs.
  This paper is the corrected version of (Gordinowicz, 2018) unified with the
corrigendum.


title:
Photospheric and chromospheric magnetic activity of seismic solar
  analogs. Observational inputs on the solar/stellar connection from Kepler and
  Hermes

abstract:
  We identify a set of 18 solar analogs among the seismic sample of solar-like
stars observed by the Kepler satellite rotating between 10 and 40 days. This
set is constructed using the asteroseismic stellar properties derived using
either the global oscillation properties or the individual acoustic
frequencies. We measure the magnetic activity properties of these stars using
observations collected by the photometric Kepler satellite and by the
ground-based, high-resolution Hermes spectrograph mounted on the Mercator
telescope. The photospheric (Sph) and chromospheric (S index) magnetic activity
levels of these seismic solar analogs are estimated and compared in relation to
the solar activity. We show that the activity of the Sun is comparable to the
activity of the seismic solar analogs, within the maximum-to-minimum temporal
variations of the 11-year solar activity cycle 23. In agreement with previous
studies, the youngest stars and fastest rotators in our sample are actually the
most active. The activity of stars older than the Sun seems to not evolve much
with age. Furthermore, the comparison of the photospheric, Sph, with the
well-established chromospheric, S index, indicates that the Sph index can be
used to provide a suitable magnetic activity proxy which can be easily
estimated for a large number of stars from space photometric observations.


title: On Lie algebras consisting of locally nilpotent derivations

abstract:
  Let $K$ be an algebraically closed field of characteristic zero and $A$ an
integral $K$-domain. The Lie algebra $Der_{K}(A)$ of all $K$-derivations of $A$
contains the set $LND(A)$ of all locally nilpotent derivations. The structure
of $LND(A)$ is of great interest, and the question about properties of Lie
algebras contained in $LND(A)$ is still open. An answer to it in the finite
dimensional case is given. It is proved that any finite dimensional (over $K$)
subalgebra of $Der_{K}(A)$ consisting of locally nilpotent derivations is
nilpotent. In the case $A=K[x, y],$ it is also proved that any subalgebra of
$Der_{K}(A)$ consisting of locally nilpotent derivations is conjugated by an
automorphism of $K[x, y]$ with a subalgebra of the triangular Lie algebra.


title: Micelles Hydrodynamics

abstract:
  A micelle consists of monolayer of lipid molecules containing hydrophilic
head and hydrophobic tail. These amphiphilic molecules in aqueous environment
aggregate spontaneously into monomolecular layer held together due to
hydrophobic effect by weak non-covalent forces. Micelles are flexible surfaces
that show variety of shapes of different topology, but remarkably in mechanical
equilibrium conditions they are spherical in shape. The shape and size of a
micelle are functions of many variables such as lipid concentration,
temperature, ionic strength, etc. Addressing the question, why the shape of
micelles is sphere in mechanical equilibrium conditions, analytically proved to
be a difficult problem. In the following paper we offer the shortest and
elegant analytical proof of micelles spheroidal nature when they are
thermodynamically equilibrated with solvent. The formalism presented in this
paper can be readily extended to any homogenous surfaces, such are vesicles and
membranes.


title:
Personal Information Leakage During Password Recovery of Internet
  Services

abstract:
  In this paper we examine the standard password recovery process of large
Internet services such as Gmail, Facebook, and Twitter. Although most of these
services try to maintain user privacy, with regard to registration information
and other personal information provided by the user, we demonstrate that
personal information can still be obtained by unauthorized individuals or
attackers. This information includes the full (or partial) email address, phone
number, friends list, address, etc. We examine different scenarios and
demonstrate how the details revealed in the password recovery process can be
used to deduct more focused information about users.


title: Surpassing the shot-noise limit by homodyne-mediated feedback

abstract:
  Entangled systems with large quantum Fisher information (QFI) can be used to
outperform the standard quantum limit of the separable systems in quantum
metrology. However, the interaction between the system and the environments
inevitably leads to decoherence and decrease of the QFI, and it is not clear
whether the entanglement systems can be better resource than separable systems
in the realistic physical condition. In this work, we study the steady QFI of
two driven and collectively damped qubits with homodyne-mediated feedback. We
show that the steady QFI can be significantly enhanced both in the cases of
symmetric feedback and nonsymmetric feedback, and the shot-noise limit of
separable states can be surpassed in both cases. The QFI can even achieve the
Heisenberg limit for appropriate feedback parameters and initial conditions in
the case of symmetric feedback. We also show that an
initial-condition-independent steady QFI can be obtained by using nonsymmetric
feedback.


title:
Semi-globally Exponential Trajectory Tracking for a Class of Spherical
  Robots

abstract:
  A spherical robot consists of an externally spherical rigid body rolling on a
two-dimensional surface, actuated by an auxiliary mechanism. For a class of
actuation mechanisms, we derive a controller for the geometric center of the
sphere to asymptotically track any sufficiently smooth reference trajectory,
with robustness to bounded, constant uncertainties in the inertial properties
of the sphere and actuation mechanism, and to constant disturbance forces
including, for example, from constant inclination of the rolling surface. The
sphere and actuator are modeled as distinct systems, coupled by reaction
forces. It is assumed that the actuator can provide three independent control
torques, and that the actuator center of mass remains at a constant distance
from the geometric center of the sphere. We show that a necessary and
sufficient condition for such a controller to exist is that for any constant
disturbance torque acting on the sphere there is a constant input such that the
sphere and the actuator mechanism has a stable relative equilibrium. A
geometric PID controller guarantees robust, semi-global, locally exponential
stability for the position tracking error of the geometric center of the
sphere, while ensuring that actuator velocities are bounded.


title:
The Human Group Optimizer (HGO): Mimicking the collective intelligence
  of human groups as an optimization tool for combinatorial problems

abstract:
  A large number of optimization algorithms have been developed by researchers
to solve a variety of complex problems in operations management area. We
present a novel optimization algorithm belonging to the class of swarm
intelligence optimization methods. The algorithm mimics the decision making
process of human groups and exploits the dynamics of this process as an
optimization tool for combinatorial problems. In order to achieve this aim, a
continuous-time Markov process is proposed to describe the behavior of a
population of socially interacting agents, modelling how humans in a group
modify their opinions driven by self-interest and consensus seeking. As in the
case of a collection of spins, the dynamics of such a system is characterized
by a phase transition from low to high values of the overall consenus
(magnetization). We recognize this phase transition as being associated with
the emergence of a collective superior intelligence of the population. While
this state being active, a cooling schedule is applied to make agents closer
and closer to the optimal solution, while performing their random walk on the
fitness landscape. A comparison with simulated annealing as well as with a
multi-agent version of the simulated annealing is presented in terms of
efficacy in finding good solution on a NK - Kauffman landscape. In all cases
our method outperforms the others, particularly in presence of limited
knowledge of the agent.


title: Edge-Maximal Graphs on Surfaces

abstract:
  We prove that for every surface $\Sigma$ of Euler genus $g$, every
edge-maximal embedding of a graph in $\Sigma$ is at most $O(g)$ edges short of
a triangulation of $\Sigma$. This provides the first answer to an open problem
of Kainen (1974).


title:
Kelvin-Helmholtz instability in solar chromospheric jets: theory and
  observation

abstract:
  Using data obtained by the high resolution CRisp Imaging SpectroPolarimeter
instrument on the Swedish 1-m Solar Telescope, we investigate the dynamics and
stability of quiet-Sun chromospheric jets observed at disk center. Small-scale
features, such as Rapid Redshifted and Blueshifted Excursions, appearing as
high speed jets in the wings of the H$\alpha$ line, are characterized by short
lifetimes and rapid fading without any descending behavior. To study the
theoretical aspects of their stability without considering their formation
mechanism, we model chromospheric jets as twisted magnetic flux tubes moving
along their axis, and use the ideal linear incompressible magnetohydrodynamic
approximation to derive the governing dispersion equation. Analytical solutions
of the dispersion equation indicate that this type of jet is unstable to
Kelvin-Helmholtz instability (KHI), with a very short (few seconds) instability
growth time at high upflow speeds. The generated vortices and unresolved
turbulent flows associated with the KHI could be observed as broadening of
chromospheric spectral lines. Analysis of the H$\alpha$ line profiles shows
that the detected structures have enhanced line widths with respect to the
background. We also investigate the stability of a larger scale H$\alpha$ jet
that was ejected along the line-of-sight. Vortex-like features, rapidly
developing around the jet's boundary, are considered as evidence of the KHI.
The analysis of the energy equation in the partially ionized plasma shows that
the ion-neutral collisions may lead to the fast heating of the KH vortices over
timescales comparable to the lifetime of chromospheric jets.


title: Liouville-type theorems for conformal mappings and their application

abstract:
  In the present paper we prove Liouville-type theorems: non-existence theorems
for conformal mappings of complete Riemannian manifolds. In addition, we give
an application of these results to the theory of conharmonic transformations. A
part of these results was announced in our reports on the conferences
"Differential Geometry and its Applications" (July 11-15, 2016, Brno, Czech
Republic) and "International Conference on Algebra, Analysis and Geometry"
(June 26-July 2, 2016, Kazan, Russia).


title:
On the Implementation of an Or-Parallel Prolog System for Clusters of
  Multicores

abstract:
  Nowadays, clusters of multicores are becoming the norm and, although, many
or-parallel Prolog systems have been developed in the past, to the best of our
knowledge, none of them was specially designed to explore the combination of
shared and distributed memory architectures. In recent work, we have proposed a
novel computational model specially designed for such combination which
introduces a layered model with two scheduling levels, one for workers sharing
memory resources, which we named a team of workers, and another for teams of
workers (not sharing memory resources). In this work, we present a first
implementation of such model and for that we revive and extend the YapOr system
to exploit or-parallelism between teams of workers. We also propose a new set
of built-in predicates that constitute the syntax to interact with an
or-parallel engine in our platform. Experimental results show that our
implementation is able to increase speedups as we increase the number of
workers per team, thus taking advantage of the maximum number of cores in a
machine, and to increase speedups as we increase the number of teams, thus
taking advantage of adding more computer nodes to a cluster. We thus argue that
our platform is an efficient and viable alternative for exploiting implicit
or-parallelism in the currently available clusters of low cost multicore
architectures.


title:
Solution Concepts in A-Loss Recall Games: Existence and Computational
  Complexity

abstract:
  Imperfect recall games represent dynamic interactions where players forget
previously known information, such as a history of played actions. The
importance of imperfect recall games stems from allowing a concise
representation of strategies compared to perfect recall games where players
remember all information. However, most of the algorithmic results are negative
for imperfect recall games -- a Nash equilibrium~(NE) does not have to exist
and computing a best response or a maxmin strategy is NP-hard. We focus on a
subclass of imperfect recall games, called A-loss recall games, where a best
response can be found in polynomial time. We derive novel properties of A-loss
recall games, including (1) a sufficient and necessary condition for the
existence of NE in A-loss recall games, (2) example where both NE and maxmin
require irrational numbers for rational input, and (3) NP-hardness of problems
related to finding maxmin strategies and existence of a NE strategy.


title:
Cut-off Characterisation of Energy Spectra of Bright Fermi Sources:
  Current instrument limits and future possibilities

abstract:
  In this paper some of the brightest GeV sources observed by the Fermi-LAT
were analysed, focusing on their spectral cut-off region. The sources chosen
for this investigation were the brightest blazar flares of 3C~454.3 and 3C~279
and the Vela pulsar with a reanalysis with the latest Fermi-LAT software. For
the study of the spectral cut-off we first explored the Vela pulsar spectrum,
whose statistics in the time interval of the 3FGL catalog allowed strong
constraints to be obtained on the parameters. We subsequently performed a new
analysis of the flaring blazar SEDs. For these sources we obtained constraints
on the cut-off parameters under the assumption that their underlying spectral
distribution is described by a power-law with a stretched exponential cut-off.
We then highlighted the significant potential improvements on such constraints
by observations with next generation ground based Cherenkov telescopes,
represented in our study by the Cherenkov Telescope Array (CTA). Adopting
currently available simulations for this future observatory, we demonstrate the
considerable improvement in cut-off constraints achievable by observations with
this new instrument when compared with that achievable by satellite
observations.


title: Dipole model analysis of the new HERA I+II data

abstract:
  We use the dipole model to analyze the inclusive DIS cross section data,
obtained from the HERA I+II measurements \cite{Abramowicz:2015mha}. We show
that these combined data are very well described within the dipole model
framework, which is complemented with a valence quark structure functions. Our
motivation is to investigate the gluon density with the BGK dipole model
\cite{BGK} as an alternative to the PDF approach. BGK dipole model uses for
evolution the DGLAP mechanism in the $kt$ factorization scheme (in contrast to
the collinear factorization for PDFs). We confirm our results from the previous
paper \cite{Luszczak:2013rxa} with old HERA data \cite{HERA2010}. In addition
we also performed a first, preliminary investigation of saturation. The
analysis was done in the xFitter framework
\cite{xFitter,xFitter2,xFitter3,xFitter4,xFitter5}.}


title:
On the F-index and F-coindex of the line graphs of the subdivision
  graphs

abstract:
  The aim of this work is to investigate the F-index and F-coindex of the line
graphs of the cycle graphs, star graphs, tadpole graphs, wheel graphs and
ladder graphs using the subdivision concepts. F-index of the line graph of
subdivision graph of square grid graph, 2D-lattice, nanotube and nanotorus of
$TUC_{4}C_{8}[p, q]$ are also investigated here.


title: Stratifications of flag spaces and functoriality

abstract:
  We define quotient stacks of "zip flags". They form towers above the stack of
$G$-zips introduced by Moonen, Pink, Wedhorn and Ziegler. We define a
stratification on the stack of zip flags, and prove that it is principally
pure, under a certain assumption on $p$. The fiber product with a Shimura
variety of Hodge-type is a generalization of flag spaces considered by
Ekedahl-Van der Geer. For large $p$, we prove that all strata are affine. We
prove a theorem on discreteness of fibers for finite morphisms between stacks
of $G$-zips. This allows us to prove that the zip stratification is principally
pure for all primes $p$, for zip data of Hodge-type. This provides a second
proof, entirely in characteristic $p$, of the existence of generalized Hasse
invariants for Ekedahl-Oort strata in the good reduction of Shimura varieties
of Hodge-type.


title: Recoding Color Transfer as a Color Homography

abstract:
  Color transfer is an image editing process that adjusts the colors of a
picture to match a target picture's color theme. A natural color transfer not
only matches the color styles but also prevents after-transfer artifacts due to
image compression, noise, and gradient smoothness change. The recently
discovered color homography theorem proves that colors across a change in
photometric viewing condition are related by a homography. In this paper, we
propose a color-homography-based color transfer decomposition which encodes
color transfer as a combination of chromaticity shift and shading adjustment. A
powerful form of shading adjustment is shown to be a global shading curve by
which the same shading homography can be applied elsewhere. Our experiments
show that the proposed color transfer decomposition provides a very close
approximation to many popular color transfer methods. The advantage of our
approach is that the learned color transfer can be applied to many other images
(e.g. other frames in a video), instead of a frame-to-frame basis. We
demonstrate two applications for color transfer enhancement and video color
grading re-application. This simple model of color transfer is also important
for future color transfer algorithm design.


title:
Ground state and orbital stability for the NLS equation on a general
  starlike graph with potentials

abstract:
  We consider a nonlinear Schr\"odinger equation (NLS) posed on a graph or
network composed of a generic compact part to which a finite number of
half-lines are attached. We call this structure a starlike graph. At the
vertices of the graph interactions of $\delta$-type can be present and an
overall external potential is admitted. Under general assumptions on the
potential, we prove that the NLS is globally well-posed in the energy domain.
We are interested in minimizing the energy of the system on the manifold of
constant mass ($L^2$-norm). When existing, the minimizer is called ground state
and it is the profile of an orbitally stable standing wave for the NLS
evolution. We prove that a ground state exists for sufficiently small masses
whenever the quadratic part of the energy admits a simple isolated eigenvalue
at the bottom of the spectrum (the linear ground state). This is a wide
generalization of a result previously obtained for a star graph with a single
vertex. The main part of the proof is devoted to prove the concentration
compactness principle for starlike structures; this is non trivial due to the
lack of translation invariance of the domain. Then we show that a minimizing
bounded $H^1$ sequence for the constrained NLS energy with external linear
potentials is in fact convergent if its mass is small enough. Examples are
provided with discussion of hypotheses on the linear part.


title:
On Integrals, Hamiltonian and Metriplectic Formulations of 3D Polynomial
  Systems

abstract:
  We apply the Darboux integrability method to determine first integrals and
Hamiltonian formulations of three dimensional polynomial systems; namely the
reduced three-wave interaction problem, the Rabinovich system, the
Hindmarsh-Rose model, and the oregonator model. Additionally, we investigate
their Hamiltonian, Nambu-Poisson and metriplectic characters.


title:
Photoproduction of the scalar mesons $f_0(500)$ and $f_0(980)$ off the
  nucleon

abstract:
  We investigate photoproduction of the scalar mesona off the nucleon, using
the effective Lagrangians and the Regge approach. We first study $f_0(980)$
photoproduction, replacing the Feynman propagator with the Regge ones for the
$\rho$-meson exchange in the $t$-channel. The model parameters are fixed by
reproducing the experimental data on the differential cross section. We then
apply the same method to $f_0(500)$ or $\sigma$ photoproduction with the same
parameters for the Regge propagator. Since the threshold energy of the
$f_0(500)$ production is rather low, $N^*$ resonances, which can decay into the
nucleon and two pions in the isoscalar and scalar state, can come into play in
the $s$-channel. To examine the effects of the $N^*$ resonances, we set up two
models to look into the respective contribution of the $N^*$ resonances. We
find that in particular $N^*(1440)$ and $N^*(1680)$ play important roles in
$f_0(500)$ photoproduction. We discuss the physical implications of the present
results.


title:
Electroweak precision observables and Higgs-boson signal strengths in
  the Standard Model and beyond: present and future

abstract:
  We present results from a state-of-the-art fit of electroweak precision
observables and Higgs-boson signal-strength measurements performed using 7 and
8 TeV data from the Large Hadron Collider. Based on the HEPfit package, our
study updates the traditional fit of electroweak precision observables and
extends it to include Higgs-boson measurements. As a result we obtain
constraints on new physics corrections to both electroweak observables and
Higgs-boson couplings. We present the projected accuracy of the fit taking into
account the expected sensitivities at future colliders.


title:
Computing Maxmin Strategies in Extensive-Form Zero-Sum Games with
  Imperfect Recall

abstract:
  Extensive-form games with imperfect recall are an important game-theoretic
model that allows a compact representation of strategies in dynamic strategic
interactions. Practical use of imperfect recall games is limited due to
negative theoretical results: a Nash equilibrium does not have to exist,
computing maxmin strategies is NP-hard, and they may require irrational
numbers. We present the first algorithm for approximating maxmin strategies in
two-player zero-sum imperfect recall games without absentmindedness. We modify
the well-known sequence-form linear program to model strategies in imperfect
recall games and use a recent technique to approximate bilinear terms. Our main
algorithm is a branch-and-bound search over these linear programs that provably
reaches a desired approximation after an exponential number of steps in the
size of the game. Experimental evaluation shows that the proposed algorithm can
approximate maxmin strategies of randomly generated imperfect recall games of
sizes beyond toy-problems within few minutes.


title: On maximal agreement couplings

abstract:
  We call a coupling of two stochastic processes which maximizes the time until
the first disagreement a maximal agreement coupling. We show that such a
coupling always exists. Furthermore, it is possible to construct a lower bound
on the disagreement time which is independent of one of the two processes.


title: Strong failures of higher analogs of Hindman's theorem

abstract:
  We show that various analogs of Hindman's Theorem fail in a strong sense when
one attempts to obtain uncountable monochromatic sets:
  Theorem 1: There exists a colouring $c:\mathbb R\rightarrow\mathbb Q$, such
that for every $X\subseteq\mathbb R$ with $|X|=|\mathbb R|$, and every colour
$\gamma\in\mathbb Q$, there are two distinct elements $x_0,x_1$ of $X$ for
which $c(x_0+x_1)=\gamma$. This forms a simultaneous generalization of a
theorem of Hindman, Leader and Strauss and a theorem of Galvin and Shelah.
  Theorem 2: For every Abelian group $G$, there exists a colouring
$c:G\rightarrow\mathbb Q$ such that for every uncountable $X\subseteq G$, and
every colour $\gamma$, for some large enough integer $n$, there are pairwise
distinct elements $x_0,\ldots,x_n$ of $X$ such that $c(x_0+\cdots+x_n)=\gamma$.
In addition, it is consistent that the preceding statement remains valid even
after enlarging the set of colours from $\mathbb Q$ to $\mathbb R$.
  Theorem 3: Let $\circledast_\kappa$ assert that for every Abelian group $G$
of cardinality $\kappa$, there exists a colouring $c:G\rightarrow G$ such that
for every positive integer $n$, every $X_0,\ldots,X_n \in[G]^\kappa$, and every
$\gamma\in G$, there are $x_0\in X_0,\ldots, x_n\in X_n$ such that
$c(x_0+\cdots+x_n)=\gamma$. Then $\circledast_\kappa$ holds for unboundedly
many uncountable cardinals $\kappa$, and it is consistent that
$\circledast_\kappa$ holds for all regular uncountable cardinals $\kappa$.


title: Penalized Maximum Likelihood Estimator for Skew Normal Mixtures

abstract:
  Skew normal mixture models provide a more flexible framework than the popular
normal mixtures for modelling heterogeneous data with asymmetric behaviors. Due
to the unboundedness of likelihood function and the divergency of shape
parameters, the maximum likelihood estimators of the parameters of interest are
often not well defined, leading to dissatisfactory inferential process. We put
forward a proposal to deal with these issues simultaneously in the context of
penalizing the likelihood function. The resulting penalized maximum likelihood
estimator is proved to be strongly consistent when the putative order of
mixture is equal to or larger than the true one. We also provide penalized
EM-type algorithms to compute penalized estimators. Finite sample performances
are examined by simulations and real data applications and the comparison to
the existing methods.


title:
Three-dimensional simulation of nonwoven fabrics using a greedy
  approximation of the distribution of fiber directions

abstract:
  An elementary algorithm is used to simulate the industrial production of a
fiber of a 3-dimensional nonwoven fabric. The algorithm simulates the fiber as
a polyline where the direction of each segment is stochastically drawn based on
a given probability density function (PDF) on the unit sphere. This PDF is
obtained from data of directions of fiber fragments which originate from
computer tomography scans of a real non-woven fabric. However, the simulation
algorithm requires numerous evaluations of the PDF. Since the established
technique of a kernel density estimator leads to very high computational costs,
a novel greedy algorithm for estimating a sparse representation of the PDF is
introduced. Numerical tests for a synthetic and a real example are presented.
In a realistic scenario, the introduced sparsity ansatz leads to a reduction of
the computation time for 100 fibers from nearly 40 days to 41 minutes.


title: Gauge symmetry from decoupling

abstract:
  Gauge symmetries emerge from a redundant description of the effective action
for light degrees of freedom after the decoupling of heavy modes. This
redundant description avoids the use of explicit constraints in configuration
space. For non-linear constraints the gauge symmetries are non-linear. In a
quantum field theory setting the gauge symmetries are local and can describe
Yang-Mills theories or quantum gravity. We formulate gauge invariant fields
that correspond to the non-linear light degrees of freedom. In the context of
functional renormalization gauge symmetries can emerge if the flow generates or
preserves large mass-like terms for the heavy degrees of freedom. They
correspond to a particular form of gauge fixing terms in quantum field
theories.


title: Super-Planckian electron cooling in a van der Waals stack

abstract:
  Radiative heat transfer (RHT) between macroscopic bodies at separations that
are much smaller than the thermal wavelength is ruled by evanescent
electromagnetic modes and can be orders of magnitude more efficient than its
far-field counterpart, which is described by the Stefan-Boltzmann law. In this
Letter we present a microscopic theory of RHT in van der Waals stacks
comprising graphene and a natural hyperbolic material, i.e. hexagonal boron
nitride (hBN). We demonstrate that RHT between hot carriers in graphene and
hyperbolic phonon-polaritons in hBN is extremely efficient at room temperature,
leading to picosecond time scales for the carrier cooling dynamics.


title: Constraining Milky Way mass with Hypervelocity Stars

abstract:
  Context. Although a variety of techniques have been employed for determining
the Milky Way dark matter halo mass distribution, the range of allowed masses
spans both light and heavy values. Knowing the precise mass of our Galaxy is
important for placing the Milky Way in a cosmological $\Lambda$CDM context.
Aims. We show that hypervelocity stars (HVSs) ejected from the center of the
Milky Way galaxy can be used to constrain the mass of its dark matter halo.
Methods. We use the asymmetry in the radial velocity distribution of halo stars
due to escaping HVSs, which depends on the halo potential (escape speed) as
long as the round trip orbital time is shorter than the stellar lifetime, to
discriminate between different models for the Milky Way gravitational
potential. Results. Adopting a characteristic HVS travel time of $330$ Myr,
which corresponds to the average mass of main sequence HVSs, we find that
current data favors a mass for the Milky Way in the range $(1.2$-$1.9)\times
10^{12} \mathrm{M}_\odot$.


title:
Asteroid (469219) 2016 HO3, the smallest and closest Earth
  quasi-satellite

abstract:
  A number of Earth co-orbital asteroids experience repeated transitions
between the quasi-satellite and horseshoe dynamical states. Asteroids 2001 GO2,
2002 AA29, 2003 YN107 and 2015 SO2 are well-documented cases of such a
dynamical behaviour. These transitions depend on the gravitational influence of
other planets, owing to the overlapping of a multiplicity of secular
resonances. Here, we show that the recently discovered asteroid (469219) 2016
HO3 is a quasi-satellite of our planet -the fifth one, joining the ranks of
(164207) 2004 GU9, (277810) 2006 FV35, 2013 LX28 and 2014 OL339. This new Earth
co-orbital also switches repeatedly between the quasi-satellite and horseshoe
configurations. Its current quasi-satellite episode started nearly 100 yr ago
and it will end in about 300 yr from now. The orbital solution currently
available for this object is very robust and our full N-body calculations show
that it may be a long-term companion (time-scale of Myr) to our planet. Among
the known Earth quasi-satellites, it is the closest to our planet and as such,
a potentially accessible target for future in situ study. Due to its presumably
lengthy dynamical relationship with the Earth and given the fact that at
present and for many decades this transient object remains well positioned with
respect to our planet, the results of spectroscopic studies of this small body,
26-115 m, may be particularly useful to improve our understanding of the
origins -local or captured- of Earth's co-orbital asteroid population. The
non-negligible effect of the uncertainty in the value of the mass of Jupiter on
the stability of this type of co-orbitals is also briefly explored.


title: Pathways to self-organization: crystallization via nucleation and growth

abstract:
  Crystallization, a prototypical self-organization process during which a
disordered state spontaneously transforms into a crystal characterized by a
regular arrangement of its building blocks, usually proceeds by nucleation and
growth. In the initial stages of the transformation, a localized nucleus of the
new phase forms in the old one due to a random fluctuation. Most of these
nuclei disappear after a short time, but rarely a crystalline embryo may reach
a critical size after which further growth becomes thermodynamically favorable
and the entire system is converted into the new phase. In these lecture notes,
we will discuss several theoretical concepts and computational methods to study
crystallization. More specifically, we will address the rare event problem
arising in the simulation of nucleation processes and explain how to calculate
nucleation rates accurately. Particular attention is directed towards
discussing statistical tools to analyze crystallization trajectories and
identify the transition mechanism.


title:
No actual measurement ... was required: Maxwell and Cavendish's null
  method for the inverse square law of electrostatics

abstract:
  In 1877 James Clerk Maxwell and his student Donald MacAlister refined Henry
Cavendish's 1773 null experiment demonstrating the absence of electricity
inside a charged conductor. This null result was a mathematical prediction of
the inverse square law of electrostatics, and both Cavendish and Maxwell took
the experiment as verifying the law. However, Maxwell had already expressed
absolute conviction in the law, based on results of Michael Faraday's. So, what
was the value to him of repeating Cavendish's experiment? After assessing
whether the law was as secure as he claimed, this paper explores its central
importance to the electrical programme that Maxwell was pursuing. It traces the
historical and conceptual re-orderings through which Maxwell established the
law by constructing a tradition of null tests and asserting the superior
accuracy of the method. Maxwell drew on his developing 'doctrine of method' to
identify Cavendish's experiment as a member of a wider class of null methods.
By doing so, he appealed to the null practices of telegraph engineers, diverted
attention from the flawed logic of the method, and sought to localise issues
around the mapping of numbers onto instrumental indications, on the grounds
that 'no actual measurement ... was required'.


title: The sandpile model on K_{m,n} and the rank of its configurations

abstract:
  We present an algorithm to compute the rank of a configuration of the
sandpile model for the complete bipartite graph K_{m,n} of complexity O(m+n).
Furthermore, we provide a formula for the generating function of parking sorted
configurations on complete bipartite graphs K_{m,n} according to rank, degree,
and the sizes m and n.
  The results in the present paper are similar to those found by Robert Cori
and the second named author for the complete graph K_{n+1}, and they rely on
the analysis of certain operators on the stable sorted configurations of
K_{m,n} developed in a previous work by the authors together with
Jean-Christophe Aval and Mark Dukes.


title: Magnetic quantum dots and rings in two dimensions

abstract:
  We consider the motion of electrons confined to a two dimensional plane with
an externally applied perpendicular inhomogeneous magnetic field, both with and
without a Coulomb potential. We find that as long as the magnetic field is
slowly-decaying, bound states in magnetic quantum dots are indeed possible.
Several example cases of such magnetic quantum dots are considered in which one
can find the eigenvalues and eigenfunctions in closed form, including two
hitherto unknown quasi-exactly solvable models treated with confluent and
biconfluent Heun polynomials. It is shown how a modulation of the strength of
the magnetic field can exclude magnetic vortex-like states, rotating with a
certain angular momenta and possessing a definite spin orientation, from
forming. This indicates one may induce localization-delocalization transitions
and suggests a mechanism for spin-separation.

categories: cond-mat.mes-hall math-ph math.MP quant-ph


title:
The bursting nature of star formation in compact star-forming galaxies
  from the Sloan Digital Sky Survey

abstract:
  We study integrated characteristics of ~14000 low-redshift (0<z<1) compact
star-forming galaxies (SFGs) selected from the Data Release 12 of the Sloan
Digital Sky Survey. It is found that emission of these galaxies is dominated by
strong young bursts of star formation, implying that their luminosities
experience rapid variations on a time scale of a few Myr. Reducing integrated
characteristics of these galaxies to zero burst age would result in a
considerably tighter and almost linear relation between stellar mass and star
formation rate (SFR). The same correction implies that the specific star
formation rate (the ratio of SFR and stellar mass) is not dependent on the
galaxy stellar mass. We conclude that the correction for rapid luminosity
evolution must be taken into account in a similar way when comparing different
samples of low- and high-redshift SFGs. If the bursting nature of star
formation and young burst ages are characteristics of the galaxies selected at
high redshifts, the age correction of observed SFRs derived from the Hbeta
emission line or UV continua would modify the derived SFR densities in the
early universe.


title: Cognitive Sub-Nyquist Hardware Prototype of a Collocated MIMO Radar

abstract:
  We present the design and hardware implementation of a radar prototype that
demonstrates the principle of a sub-Nyquist collocated multiple-input
multiple-output (MIMO) radar. The setup allows sampling in both spatial and
spectral domains at rates much lower than dictated by the Nyquist sampling
theorem. Our prototype realizes an X-band MIMO radar that can be configured to
have a maximum of 8 transmit and 10 receive antenna elements. We use frequency
division multiplexing (FDM) to achieve the orthogonality of MIMO waveforms and
apply the Xampling framework for signal recovery. The prototype also implements
a cognitive transmission scheme where each transmit waveform is restricted to
those pre-determined subbands of the full signal bandwidth that the receiver
samples and processes. Real-time experiments show reasonable recovery
performance while operating as a 4x5 thinned random array wherein the combined
spatial and spectral sampling factor reduction is 87.5% of that of a filled
8x10 array.


title: How to observe duality in entanglement of two distinguishable particles?

abstract:
  The entanglement between two bosons or fermions can be accessed if there
exists an auxiliary degree of freedom which can be used to label and
effectively distinguish the two particles. For some types of entanglement
between two indistinguishable particles one can observe duality, i.e., if the
entanglement is present in the Hilbert space H and an auxiliary Hilbert space
H' is used to label the particles, then if we used H as a label the
entanglement would be present in H'. For distinguishable particles this effect
does not occur because of superselection rules which prevent superpositions of
different types of particles. However, it is known that superselection rules
can be bypassed if one uses special auxiliary states that are known as
reference frames. Here we study properties of reference frames which allow for
an observation of a duality in entanglement between two distinguishable
particles. Finally, we discuss the consequences of this result from the
resource-theoretic point of view.


title: Instantaneous Control of Brownian Motion with a Positive Lead Time

abstract:
  Consider a storage system where the content is driven by a Brownian motion
absent control. At any time, one may increase or decrease the content at a cost
proportional to the amount of adjustment. A decrease of the content takes
effect immediately, while an increase is realized after a fixed lead time
$\lt$. Holding costs are incurred continuously over time and are a convex
function of the content. The objective is to find a control policy that
minimizes the expected present value of the total costs. Due to the positive
lead time for upward adjustments, one needs to keep track of all the
outstanding upward adjustments as well as the actual content at time $t$ as
there may also be downward adjustments during $[t,t+\lt)$, i.e., the state of
the system is a function on $[0,\ell]$. To the best of our knowledge, this is
the first paper to study instantaneous control of stochastic systems in such a
functional setting. We first extend the concept of $L^\natural$-convexity to
function spaces and establish the $L^\natural$-convexity of the optimal cost
function. We then derive various properties of the cost function and identify
the structure of the optimal policy as a state-dependent two-sided reflection
mapping making the minimum amount of adjustment necessary to keep the system
states within a certain region.


title: Emergence of the stripe-domain phase in patterned Permalloy films

abstract:
  The occurrence of stripe domains in ferromagnetic Permalloy
(Py=Fe$_{20}$Ni$_{80}$) is a well known phenomenon which has been extensively
observed and characterized. This peculiar magnetic configuration appears only
in films with a thickness above a critical value ($d_{cr}$), which is strongly
determined by the sputtering conditions (i.e. deposition rate, temperature,
magnetic field). So far, $d_{cr}$ has usually been presented as the boundary
between the homogeneous (H) and stripe-domains (SD) regime, respectively below
and above $d_{cr}$. In this work we study the transition from the H to the SD
regime in thin films and microstructured bridges of Py with different
thicknesses. We find there is an intermediate regime, over a quite significant
thickness range below d$_{cr}$, which is signaled in confined structures by a
quickly changing domain-wall configuration and by a broadening of the
magnetoresistance dip at the coercive field. We call this the emerging
stripe-domains (ESD) regime. The transition from the ESD to the SD regime is
accompanied by a sharp increase of the magnetoresistance ratio at the thickness
where stripes appear in MFM.


title: Multipartite Causal Correlations: Polytopes and Inequalities

abstract:
  We consider the most general correlations that can be obtained by a group of
parties whose causal relations are well-defined, although possibly
probabilistic and dependent on past parties' operations. We show that, for any
fixed number of parties and inputs and outputs for each party, the set of such
correlations forms a convex polytope, whose vertices correspond to
deterministic strategies, and whose (nontrivial) facets define so-called causal
inequalities. We completely characterize the simplest tripartite polytope in
terms of its facet inequalities, propose generalizations of some inequalities
to scenarios with more parties, and show that our tripartite inequalities can
be violated within the process matrix formalism, where quantum mechanics is
locally valid but no global causal structure is assumed.


title: Deep Learning for Detecting Multiple Space-Time Action Tubes in Videos

abstract:
  In this work, we propose an approach to the spatiotemporal localisation
(detection) and classification of multiple concurrent actions within temporally
untrimmed videos. Our framework is composed of three stages. In stage 1,
appearance and motion detection networks are employed to localise and score
actions from colour images and optical flow. In stage 2, the appearance network
detections are boosted by combining them with the motion detection scores, in
proportion to their respective spatial overlap. In stage 3, sequences of
detection boxes most likely to be associated with a single action instance,
called action tubes, are constructed by solving two energy maximisation
problems via dynamic programming. While in the first pass, action paths
spanning the whole video are built by linking detection boxes over time using
their class-specific scores and their spatial overlap, in the second pass,
temporal trimming is performed by ensuring label consistency for all
constituting detection boxes. We demonstrate the performance of our algorithm
on the challenging UCF101, J-HMDB-21 and LIRIS-HARL datasets, achieving new
state-of-the-art results across the board and significantly increasing
detection speed at test time. We achieve a huge leap forward in action
detection performance and report a 20% and 11% gain in mAP (mean average
precision) on UCF-101 and J-HMDB-21 datasets respectively when compared to the
state-of-the-art.


title: Study of the pd(dp) -> 3He pi pi reactions close to threshold

abstract:
  New experimental data on the pd -> 3He pi+ pi- reaction obtained with the
COSY-MOMO detector below the three-pion threshold are presented. The reaction
was also studied in inverse kinematics with a deuteron beam and the higher
counting rates achieved were especially important at low excess energies. The
comparison of these data with inclusive pd -> 3He+X rates allowed estimates
also to be made of pi0 pi0 production. The results confirm our earlier findings
that close to threshold there is no enhancement at low excitation energies in
the pi+ pi- system, where the data seem largely suppressed compared to phase
space. Possible explanations for this behavior, such as strong p- waves in the
pi+pi- -system or the influence of two-step processes, are explored.


title: Matters of time directionality in classical and quantum physics

abstract:
  This report offers a modern perspective on the question of time
directionality as it arises in a classical and quantum mechanical context,
based on key developments in the field of gravitational physics. Important
clarifications are achieved regarding, in particular, the concepts of time
reversal, negative energy and causality. From this analysis emerges an improved
understanding of the general relativistic concept of stress-energy of matter as
being a manifestation of local variations in the energy density of zero-point
vacuum fluctuations. Based on those developments a set of axioms is proposed
from which are derived generalized gravitational field equations which actually
constitute a simplification of relativity theory in the presence of negative
energy matter and vacuum energy. Those results are then applied to provide
original solutions to several long-standing problems in theoretical cosmology
and concerning the foundations of quantum theory, including the problem of the
nature of dark matter and dark energy, that of the origin of thermodynamic time
asymmetry and several other issues traditionally approached using inflation
theory. Significant new insights are also provided concerning gravitational
entropy, the problem of quantum non-locality, that of the emergence of time in
quantum cosmology as well as the problem of the persistence of
quasiclassicality following decoherence.


title: Fixed-Effect Regressions on Network Data

abstract:
  This paper considers inference on fixed effects in a linear regression model
estimated from network data. An important special case of our setup is the
two-way regression model. This is a workhorse technique in the analysis of
matched data sets, such as employer-employee or student-teacher panel data. We
formalize how the structure of the network affects the accuracy with which the
fixed effects can be estimated. This allows us to derive sufficient conditions
on the network for consistent estimation and asymptotically-valid inference to
be possible. Estimation of moments is also considered. We allow for general
networks and our setup covers both the dense and sparse case. We provide
numerical results for the estimation of teacher value-added models and
regressions with occupational dummies.


title: Research trends in structural software complexity

abstract:
  There are many dimensions of software complexity. In this article, we explore
how structural complexity is measured and used to study and control evolving
software systems. We also present the current research challenges and emerging
trends in this domain that has remained active for nearly four decades, and
continues to evolve.


title: The Bi-directional Moving Structures in a Coronal Bright Point

abstract:
  We report the bi-directional moving structures in a coronal bright point
(CBP) on 2015 July 14. It is observed by the Atmospheric Imaging Assembly (AIA)
onboard Solar Dynamics Observatory (SDO). This CBP has a lifetime of about 10
minutes, and a curved shape. The observations show that many bright structures
are moving intermittently outward from the CBP brightness core. Such moving
structures are clearly seen at AIA 171, 193, 211, 131, 94, 335 and 304 A,
slit-jaw (SJI) 1330 and 1400 A. In order to analyze these moving structures,
the CBP is cut along the moving direction with a curved slit from the AIA and
SJI images. Then we can obtain the time-distance slices, including the
intensity and intensity-derivative diagrams, from which, the moving structures
are recognized as the oblique streaks, and they are characterized by the
bi-direction, simultaneity, symmetry, and periodicity. The average speed is
around 300 km/s, while the typically period is about 90 s. All these features
(including the bi-directional flows and their periodicity) can be detected
simultaneously at all the 9 wavelengths. This CBP takes place at the site
between a small pair of magnetic polarities. High time resolution observations
show that they are moving close to each other during its lifetime. These facts
support the magnetic reconnection model of the CBP and the bi-directional
moving structures could be the observational outflows after the reconnection.
Therefore, they can be as the direct observation evidence of the magnetic
reconnection.


title: Optimal Population in a Finite Horizon

abstract:
  A favorable population schedule for the entire potential human family is
sought, under the overlapping generations framework, by treating population (or
fertility) as a planning variable in a dynamical social welfare maximization
context. The utilitarian and maximin social welfare functions are examined,
with zero future discounting, while infinity in the maximand is circumvented by
introducing the depletion of energy resources and its postponement through
technological innovations. The model is formulated as a free-horizon dynamical
planning problem, solved via a non-linear optimizer. Under exploratory
scenarios, we visualize the potential trade-offs between the two welfare
criteria.