title:
On the group of automorphisms of the Brandt $\lambda^0$-extension of a
  monoid with zero

abstract:
  The group of automorphisms of the Brandt $\lambda^0$-extension
$B^0_\lambda(S)$ of an arbitrary monoid $S$ with zero is described. In
particular we show that the group of automorphisms
$\mathbf{Aut}(B_{\lambda}^0(S))$ of $B_{\lambda}^0(S)$ is isomorphic to a
homomorphic image of the group defines on the Cartesian product
$\mathscr{S}_{\lambda}\times \mathbf{Aut}(S)\times H_1^{\lambda}$ with the
following binary operation: \begin{equation*}
  [\varphi,h,u]\cdot[\varphi^{\prime},h^{\prime},u^{\prime}]=
[\varphi\varphi^{\prime},hh^{\prime},\varphi u^{\prime}\cdot uh^{\prime}],
\end{equation*} where $\mathscr{S}_{\lambda}$ is the group of all bijections of
the cardinal $\lambda$, $\mathbf{Aut}(S)$ is the group of all automorphisms of
the semigroup $S$ and $H_1^{\lambda}$ is the direct $\lambda$-power of the
group of units $H_1$ of the monoid $S$.


title:
Modelling Stock-market Investors as Reinforcement Learning Agents
  [Correction]

abstract:
  Decision making in uncertain and risky environments is a prominent area of
research. Standard economic theories fail to fully explain human behaviour,
while a potentially promising alternative may lie in the direction of
Reinforcement Learning (RL) theory. We analyse data for 46 players extracted
from a financial market online game and test whether Reinforcement Learning
(Q-Learning) could capture these players behaviour using a risk measure based
on financial modeling. Moreover we test an earlier hypothesis that players are
"na\"ive" (short-sighted). Our results indicate that a simple Reinforcement
Learning model which considers only the selling component of the task captures
the decision-making process for a subset of players but this is not sufficient
to draw any conclusion on the population. We also find that there is not a
significant improvement of fitting of the players when using a full RL model
against a myopic version, where only immediate reward is valued by the players.
This indicates that players, if using a Reinforcement Learning approach, do so
na\"ively


title:
Multiferroic phases of the frustrated quantum spin-chain compound
  linarite

abstract:
  The dielectric properties of the prototypical frustrated ferromagnetic
spin-chain compound PbCuSO$_4$(OH)$_2$ known as linarite, are studied across
its strongly anisotropic magnetic phase diagram in single crystal samples. The
ferroelectric character of the principal low-field spin spiral phase is
confirmed. The measured polarization is fully consistent with the previously
proposed magnetic structure. Spontaneous polarization is also detected in two
other field-induced phases but in some cases is incompatible with previously
suggested models for the spin arrangement.


title: Time Derivative of Rotation Matrices: A Tutorial

abstract:
  The time derivative of a rotation matrix equals the product of a
skew-symmetric matrix and the rotation matrix itself. This article gives a
brief tutorial on the well-known result.


title:
Review of LHC experimental results on low mass bosons in multi Higgs
  models

abstract:
  A number of searches at the LHC looking for low mass ($2m_{\mu} - 62\
\mathrm{GeV}$) bosons in $\sqrt{s} = 8\ \mathrm{TeV}$ data have recently been
published. We summarise the most pertinent ones, and look at how their limits
affect a variety of supersymmetric and non-supersymmetric models which can give
rise to such light bosons: the 2HDM (Types I and II), the NMSSM, and the nMSSM.


title: On the restricted partition function

abstract:
  For a vector $\mathbf a=(a_1,\ldots,a_r)$ of positive integers we prove
formulas for the restricted partition function $p_{\mathbf a}(n): = $ the
number of integer solutions $(x_1,\dots,x_r)$ to $\sum_{j=1}^r a_jx_j=n$ with
$x_1\geq 0, \ldots, x_r\geq 0$ and its polynomial part.


title:
Static and Dynamic Magnetic Response of Fragmented Haldane-like Spin
  Chains in Layered Li3Cu2SbO6

abstract:
  The structure and the magnetic properties of layered Li3Cu2SbO6 are
investigated by powder X-ray diffraction, static susceptibility, and electron
spin resonance studies up to 330 GHz. The XRD data experimentally verify the
space group C2/m with halved unit cell volume in contrast to previously
reported C2/c. In addition, the data show significant Li/Cu-intersite exchange.
Static magnetic susceptibility and ESR measurements show two magnetic
contributions, i.e. quasi-free spins at low-temperature and a spin-gapped
magnetic subsystem, with about half of the spins being associated to each
subsystem. The data suggest ferromagnetic-antiferromagnetic alternating chains
with JFM = -285 K and JAFM = 160 K with a significant amount of Li-defects in
the chains. The results are discussed in the scenario of fragmented 1D S = 1
AFM chains with a rather high defect concentration of about 17% and associated
S = 1/2 edge states of the resulting finite Haldane chains.


title: A trapped atom interferometer with ultracold Sr atoms

abstract:
  We report on a trapped atom interferometer based on Bragg diffraction and
Bloch oscillations with alkaline-earth-metal atoms. We use a Ramsey-Bord\'e
Bragg interferometer with $^{88}$Sr atoms combined with Bloch oscillations to
extend the interferometer time. Thanks to a long coherence time for Bloch
oscillations of $^{88}$Sr atoms, we observed interference up to 1 s evolution
time in the lattice. A detailed study of decoherence sources during the Bloch
phase is also presented. While still limited in sensitivity by lattice lifetime
and beam inhomogeneity this result opens the way to high contrast trapped
interferometers with extended interrogation time.


title:
Heavy flavor $R_\text{AA}$ and $v_n$ in event-by-event viscous
  relativistic hydrodynamics

abstract:
  Recently it has been shown that a realistic description of the medium via
event-by-event viscous hydrodynamics plays an important role in the
long-standing $R_\text{AA}$ vs. $v_2$ puzzle at high $p_T$. In this proceedings
we begin to extend this approach to the heavy flavor sector by investigating
the effects of full event-by-event fluctuating hydrodynamic backgrounds on the
nuclear suppression factor and $v_2\{2\}$ of heavy flavor mesons and
non-photonic electrons at intermediate to high $p_T$. We also show results for
$v_3\{2\}$ of $B^0$ and D$^0$ for PbPb collisions at $\sqrt{s}=2.76$ TeV.


title:
Simultaneous entanglement swapping of multiple orbital angular momentum
  states of light

abstract:
  Entanglement swapping generates remote quantum correlations between particles
that have not interacted and is the cornerstone of long-distance quantum
communication, quantum networks, and fundamental tests of quantum science. In
the context of spatial modes of light, high-dimensional entanglement provides
an avenue to increase the bandwidth of quantum communications and provides more
stringent limits for tests of quantum foundations. Here we simultaneously swap
the entanglement of multiple orbital angular momentum states of light. The
system is based on a degenerate filter that cannot distinguish between
different anti-symmetric states, and thus entanglement swapping occurs for
several thousand pairs of spatial light modes simultaneously.


title:
Microwave-assisted hydrothermal synthesis of NH4V3O8 microcrystals with
  controllable morphology

abstract:
  Water-free NH4V3O8 microcrystals have been successfully synthesized by a
microwave-assisted hydrothermal method. The products were characterized by
means of X-ray diffraction, scanning electron microscopy, Fourier transform
infrared spectroscopy, thermal gravimetric analysis, cyclic voltammetry, and
galvanostatic cycling. The results show phase-pure products whose particle size
and morphology can be tailored by varying the reaction conditions, i.e.,
reaction temperature, synthesis duration, and initial pH value. For instance,
at low pH (2.5 to 3), flower-like agglomerates with primary particles of 20 to
30 microm length are found, while at pH = 5.5 single microplates with hexagonal
outline (30 to 40 microm) prevail. The sample with the comparably highest
specific surface area (11 m2/g) was studied regarding its electrochemical
performance. It shows an extraordinary initial discharge capacity of 378 mA h
g-1 at 10 mA g-1, which corresponds to the intercalation of 4.2 Li+/f.u.


title: Output feedback stabilization of the Korteweg-de Vries equation *

abstract:
  This paper presents an output feedback control law for the Korteweg-de Vries
equation. The control design is based on the backstepping method and the
introduction of an appropriate observer. The local exponential stability of the
closed-loop system is proven. Some numerical simulations are shown to
illustrate this theoretical result.


title: Twisted Linnik implies optimal covering exponent for $S^3$

abstract:
  We show that a twisted variant of Linnik's conjecture on sums of Kloosterman
sums leads to an optimal covering exponent for $S^3$.


title:
A fully diagonalized spectral method using generalized Laguerre
  functions on the half line

abstract:
  A fully diagonalized spectral method using generalized Laguerre functions is
proposed and analyzed for solving elliptic equations on the half line. We first
define the generalized Laguerre functions which are complete and mutually
orthogonal with respect to an equivalent Sobolev inner product. Then the
Fourier-like Sobolev orthogonal basis functions are constructed for the
diagonalized Laguerre spectral method of elliptic equations. Besides, a unified
orthogonal Laguerre projection is established for various elliptic equations.
On the basis of this orthogonal Laguerre projection, we obtain optimal error
estimates of the fully diagonalized Laguerre spectral method for both Dirichlet
and Robin boundary value problems. Finally, numerical experiments, which are in
agreement with the theoretical analysis, demonstrate the effectiveness and the
spectral accuracy of our diagonalized method.


title: Compaction and flow rule of oxide nanopowders

abstract:
  Transparent Al2O3 ceramics have attracted considerable interest for use in a
wide range of optical, electronic and structural applications. The fabrication
of these ceramics using powder metallurgy processes requires the development of
theoretical approaches to the compaction of nanopowders. In this work, we
investigate the compaction processes of two model granular systems imitating
Al2O3 nanosized powders. System I is a loosely aggregated powder, and system II
is a powder strongly inclined to agglomeration (for instance, calcined powder).
The processes of isostatical (uniform), biaxial, and uniaxial compaction as
well as uniaxial compaction with simultaneous shear deformation are studied.
The energy parameters of compaction such as the energy change of elastic
interparticle interactions and dispersion interactions, dissipative energy
losses related to the processes of interparticle friction, and the total work
of compaction are calculated for all the processes. The nonapplicability of the
associated flow rule to the description of deformation processes of oxide
nanopowders is shown and an alternative plastic flow rule is suggested. A
complete system of determining the relationship of the flow including
analytical approximations of yield surfaces is obtained.


title: Distributed Adaptive Learning of Graph Signals

abstract:
  The aim of this paper is to propose distributed strategies for adaptive
learning of signals defined over graphs. Assuming the graph signal to be
bandlimited, the method enables distributed reconstruction, with guaranteed
performance in terms of mean-square error, and tracking from a limited number
of sampled observations taken from a subset of vertices. A detailed mean square
analysis is carried out and illustrates the role played by the sampling
strategy on the performance of the proposed method. Finally, some useful
strategies for distributed selection of the sampling set are provided. Several
numerical results validate our theoretical findings, and illustrate the
performance of the proposed method for distributed adaptive learning of signals
defined over graphs.


title:
Clifford theory for Yokonuma--Hecke algebras and deformation of complex
  reflection groups

abstract:
  We define and study an action of the symmetric group on the Yokonuma--Hecke
algebra. This leads to the definition of two classes of algebras. The first one
is connected with the image of the algebra of the braid group inside the
Yokonuma--Hecke algebras, and in turn with an algebra defined by Aicardi and
Juyumaya known as the algebra of braids and ties. The second one can be seen as
new deformations of complex reflection groups of type G(d,p,n). We provide
several presentations for both algebras and a complete study of their
representation theories using Clifford theory.


title:
H{\"o}lder stability in determining the potential and the damping
  coefficient in a wave equation

abstract:
  We improve the preceding results obtained by the first and the second authors
in [3]. They concern the stability issue of the inverse problem that consists
in determining the potential and the damping coefficient in a wave equation
from an initial-to-boundary operator. We partially modify the arguments in [3]
to show that actually we have H{\"o}lder stability instead of logarithmic
stability.


title: A neutrino mass model with S3 symmetry and see-saw interplay

abstract:
  We develop a see-saw model for neutrino masses and mixing with an S3\times Z3
symmetry. It involves an interplay of Type-I and Type-II see-saw contributions
of which the former is subdominant. The S3 \times Z3 quantum numbers of the
fermion and scalar fields are chosen such that the Type-II see-saw generates a
mass matrix which incorporates the atmospheric mass splitting and sets
\theta_{23} = \pi/4. The solar splitting and \theta_{13} are absent, while the
third mixing angle can achieve any value, \theta_{12}^0. Specific choices of
\theta_{12}^0 are of interest, e.g., 35.3^\circ (tribimaximal), 45.0^\circ
(bimaximal), 31.7^\circ (golden ratio), and 0^\circ (no solar mixing). The role
of the Type-I see-saw is to nudge all the above into the range indicated by the
data. The model results in novel interrelationships between these quantities
due to their common origin, making it readily falsifiable. For example, normal
(inverted) ordering is associated with \theta_{23} in the first (second)
octant. CP-violation is controlled by phases in the right-handed neutrino
Majorana mass matrix, M_{\nu R}. In their absence, only normal ordering is
admissible. When M_{\nu R} is complex the Dirac CP-phase, \delta, can be large,
i.e., \sim \pm \pi/2, and inverted ordering is also allowed. The preliminary
results from T2K and NOVA which favour normal ordering and \delta \sim -\pi/2
are indicative, in this model, of a lightest neutrino mass of 0.05 eV or more.


title:
Multi-particle correlations and KNO scaling in the medium-induced jet
  evolution

abstract:
  We study the gluon distribution produced via successive medium-induced
branchings by an energetic jet propagating through a weakly-coupled quark-gluon
plasma. We show that under suitable approximations the evolution of the jet can
be described as a classical stochastic process, which is exactly solvable. For
this process, we construct exact analytic solutions for all the n-point
correlation functions (the n-body densities in the space of energy). The
corresponding results for the one-point and the two-point functions were
already known, but those for the higher-point functions are new. These results
demonstrate strong correlations associated with the existence of common
ancestors in the branching process. By integrating these n-point functions over
the gluon energies, we deduce the mean gluon multiplicity $\langle N\rangle$ as
well as the higher moments $\langle N^p\rangle$ with $p\ge 2$. We find that the
multiplicities of the soft gluons are parametrically large and show a
remarkable regularity, known as Koba-Nielsen-Olesen (KNO) scaling: the reduced
moments $\langle N^p\rangle/\langle N\rangle^p$ are pure numbers, independent
of any of the physical parameters of the problem. We recognize a special
negative binomial distribution which is characterized by large statistical
fluctuations. These predictions can be tested in Pb+Pb collisions at the LHC,
via event-by-event measurements of the di-jet asymmetry.


title: Magnetic anisotropy and the phase diagram of chiral MnSb2O6

abstract:
  The magnetic phase diagram and low-energy magnon excitations of structurally
and magnetically chiral MnSb2O6 are reported. The specific heat and the static
magnetization are investigated in magnetic fields up to 9 and 30 T,
respectively, while the dynamicmagnetic properties are probed by X-band as well
as tunable high-frequency electron spin-resonance spectroscopy. Below TN = 11.5
K, we observe antiferromagnetic resonance modes which imply small but finite
planar anisotropy showing up in a zero-field splitting of 20 GHz. The data are
well described by means of an easy-plane two-sublattice model with the
anisotropy field BA = 0.02 T. The exchange field BE = 13 T is obtained from the
saturation field derived from the pulsed-field magnetization. A crucial role of
the small anisotropy for the spin structure is reflected by competing
antiferromagnetic phases appearing, at T = 2 K, in small magnetic fields at BC1
$\approx$ 0.5 T and BC2 = 0.9 T. We discuss the results in terms of spin
reorientation and of small magnetic fields favoring helical spin structure over
the cycloidal ground state which, at B = 0, is stabilized by the planar
anisotropy. Above TN, short-range magnetic correlations up to >=60 K and
magnetic entropy changes well above TN reflect the frustrated triangular
arrangement of Mn2+ ions in MnSb2O6.


title:
Production of $\pi^{0}$, $K^{\pm}$ and $\eta$ mesons in Pb-Pb and pp
  collisions at $\sqrt{s_{\rm NN}}=$2.76 TeV measured with the ALICE detector
  at the LHC

abstract:
  One of the key signatures of the Quark-Gluon Plasma (QGP) is the modification
of hadron transverse momentum differential cross-sections in heavy-ion
collisions (HIC) as compared to proton-proton (pp) collisions. Suppression of
hadron production at high transverse momenta ($p_{\rm T}$) in HIC has been
explained by the energy loss of the partons produced in the hard scattering
processes which traverse the deconfined quantum chromodynamic (QCD) matter. The
dependence of the observed suppression on the $p_{\rm T}$ of the measured
hadron towards higher $p_{\rm T}$ is an important input for the theoretical
understanding of jet quenching effects in the QGP and the nature of the energy
loss, while suppression towards lower $p_{\rm T}$ gives information about
collective behaviour. The ALICE experiment at the Large Hadron Collider (LHC)
performs a variety of measurements including the spectra of neutral mesons and
kaons at mid-rapidity in a wide $p_{\rm T}$ range in pp, p-Pb and Pb-Pb
collisions. An overview of ALICE results in HIC and pp collisions at
$\sqrt{s_{NN}}=$2.76 TeV of neutral pions, kaons and eta mesons as a function
of transverse momentum ($p_{\rm T}$) and centrality will be presented. Ratios
$\eta$/$\pi^{0}$, $K^{\pm}$/$\pi^{\pm}$ as well as comparisons to model
calculations will also be discussed.


title:
Stability Analysis of Population Dynamics Model in Microbial Biofilms
  with Non-participating Strains

abstract:
  The existence of phenotypic heterogeneity in single-species bacterial
biofilms is well-established in the published literature. However, the modeling
of population dynamics in biofilms from the viewpoint of social interactions,
i.e. interplay between heterotypic strains, and the analysis of this kind using
control theory are not addressed significantly. Therefore, in this paper, we
theoretically analyze the population dynamics model in microbial biofilms with
non-participating strains (coexisting with public goods producers and
non-producers) in the context of evolutionary game theory and nonlinear
dynamics. Our analysis of the replicator dynamics model is twofold: first
without the inclusion of spatial pattern, and second with the consideration of
degree of assortment. In the first case, Lyapunov stability analysis of the
stable equilibrium point of the proposed replicator system determines (1,0)
('full dominance of cooperators') as a global asymptotic stable equilibrium
whenever the return exceeds the metabolic cost of cooperation. Hence, the
global asymptotic stable nature of (1,0) in the context of non-consideration of
spatial pattern helps to justify mathematically the adversity in the
eradication of "cooperative enterprise" that is an infectious biofilm. In the
second case, we found non-existence of global asymptotic stability in the
system, and it unveils two additional phenomena - bistability and coexistence.
In this context, two inequality conditions are derived for the 'full dominance
of cooperators' and coexistence. Therefore, the inclusion of spatial pattern in
biofilms with non-competing strains intends conditional dominance of pathogenic
(with respect to the hosts) public goods producers which can be an effective
strategy towards the control of an infectious biofilm with the drug-dependent
regulation of degree of segregation.


title:
Effects of source and loss terms on the wave-pinning description of cell
  polarisation

abstract:
  A system of two Schnakenberg-like reaction-diffusion equations is
investigated analytically and numerically. The system has previously been used
as a minimal model for concentrations of GTPases involved in the process of
cell polarisation. Source and loss terms are added, breaking the mass
conservation, which was shown previously to be responsible for the generation
of stable fronts via a so-called wave-pinning mechanism. The extended model
gives rise to a unique homogeneous equilibrium in the parameter region of
interest, which loses stability via a pattern formation, or Turing bifurcation.
The bistable character of the reaction terms ensures that this bifurcation is
subcrtical for sufficiently small values of the driving parameter multiplying
the nonlinear kinetics. This subcriticality leads to the onset of a multitude
of localised solutions, through the homoclinic snaking mechanism. As the
driving parameter is further decreased, the multitude of solutions transforms
into a single pulse through a Belyakov-Devaney transition in which there is the
loss of a precursive pattern. An asymptotic analysis is used to probe the
conservative limit in which the source and loss terms vanish. Matched
asymptotic analysis shows that on an infinite domain the pulse solution
transitions into a pair of fronts, with an additional weak quadratic core and
exponential tails. On a finite domain, the core and tails disappear, leading to
the mere wave-pinning front and its mirror image.


title: FPGA implementation of the procedures for video quality assessment

abstract:
  Video resolutions used in variety of media are constantly rising. While
manufacturers struggle to perfect their screens it is also important to ensure
high quality of displayed image. Overall quality can be measured using Mean
Opinion Score (MOS). Video quality can be affected by miscellaneous artifacts,
appearing at every stage of video creation and transmission. In this paper, we
present a solution to calculate four distinct video quality metrics that can be
applied to a real time video quality assessment system. Our assessment module
is capable of processing 8K resolution in real time set at the level of 30
frames per second. Throughput of 2.19 GB/s surpasses performance of pure
software solutions. To concentrate on architectural optimization, the module
was created using high level language.


title: Tunable Magnetic Properties of Carbon-shielded NiPt Nanoalloys

abstract:
  Spherical NiPt@C nanoalloys encapsulated in carbon shells are synthesized by
means of high-pressure chemical vapour deposition. Upon variation of the
synthesis parameters, both the alloy core composition and the particle size of
the resulting spherical NixPt1-x@C nanocapsules can be controlled. The
sublimation temperatures of the Ni- and Pt-precursors are found key to control
the alloy composition and diameter. Depending on the synthesis parameters, the
diameters of the cores are tuneable in the range of 3 - 15 nm while the carbon
coatings for all conditions are 1 - 2 nm. The core particle size decreases
linearly upon increasing either of the sublimation temperatures while the Ni
and Pt content, respectively, are linearly increasing with the related
precursor temperature. Accordingly, the magnetic properties of the nanoalloys,
i.e. magnetization, remanent magnetization and critical field, are well
controlled by the two sublimation temperatures. As compared to bulk NiPt, our
data show an increase of Stoner enhancement by nanoscaling as ferromagnetism
appears in the Pt rich NiPt nanoalloy which is not observed for the related
bulk alloys. The magneto-crystalline anisotropy constants K are in the range of
0.3 - 4 x 105 J/m3 underlining that NiPt@C is a stable, highly magnetic
functional nanomaterial.


title: On Vertex Rankings of Graphs and its Relatives

abstract:
  A vertex ranking of a graph is an assignment of ranks (or colors) to the
vertices of the graph, in such a way that any simple path connecting two
vertices of equal rank, must contain a vertex of a higher rank. In this paper
we study a relaxation of this notion, in which the requirement above should
only hold for paths of some bounded length $l$ for some fixed $l$. For
instance, already the case $l=2$ exhibit quite a different behavior than proper
coloring. We prove upper and lower bounds on the minimum number of ranks
required for several graph families, such as trees, planar graphs, graphs
excluding a fixed minor and degenerate graphs.


title:
Resonant unidirectional and elastic scattering of surface plasmon
  polaritons by high-refractive index dielectric nanoparticles

abstract:
  We consider scattering of surface plasmon polaritons (SPPs) and light by
individual high-refractive-index dielectric nanoparticles (NPs) located on a
metal (gold) substrate and supporting electric and magnetic dipole resonances
in the visible spectral range. Numerical calculations are carried out by making
use of the discrete dipole approximation including the multipole decomposition
procedure. Extinction and scattering cross section spectra of spheroid silicon
NPs in visible and near-infrared are presented and discussed. The roles of the
in-plane and out-of-plane components of electric and magnetic dipoles in the
scattering processes are clarified and demonstrated. It is revealed that, owing
to the NP interaction with electromagnetic fields reflected from the substrate
(that leads to bianisotropy), the in-plane electric and magnetic dipoles can
resonantly be excited at the same wavelength. Due to this effect, the resonant
unidirectional (forward) and elastic (in-plane) scattering of SPPs by oblate
spheroid NPs can be realized within a narrow spectral range. In the case of
normal light incidence, the bianisotropy effect can provide significant
suppression of the SPP excitation because of the destructive interference
between the SPP waves generated by induced electric and magnetic dipole
moments. The results obtained open new possibilities for the Development of
SPP-based photonic components and metasurfaces, whose operation involves
resonant excitations of dielectric NPs.


title: Lepton number violation by heavy Majorana neutrino in $B$ decays

abstract:
  Heavy Majorana neutrinos are predicted in addition to ordinary active
neutrinos in the models with the seesaw mechanism. We investigate the lepton
number violation (LNV) in $B$ decays induced by such a heavy neutrino $N$ with
GeV-scale mass. Especially, we consider the decay channel $B^+ \to \mu^+ \, N
\to \mu^+ \mu^+ \pi^-$ and derive the sensitivity limits on the mixing angle
$\Theta_\mu$ by the future search experiments at Belle II and in $e^+ e^-$
collisions at the Future Circular Collider (FCC-ee).


title:
Better local hidden variable models for two-qubit Werner states and an
  upper bound on the Grothendieck constant $K_G(3)$

abstract:
  We consider the problem of reproducing the correlations obtained by arbitrary
local projective measurements on the two-qubit Werner state $\rho = v |\psi_- >
<\psi_- | + (1- v ) \frac{1}{4}$ via a local hidden variable (LHV) model, where
$|\psi_- >$ denotes the singlet state. We show analytically that these
correlations are local for $ v = 999\times689\times{10^{-6}}$ $\cos^4(\pi/50)
\simeq 0.6829$. In turn, as this problem is closely related to a purely
mathematical one formulated by Grothendieck, our result implies a new bound on
the Grothendieck constant $K_G(3) \leq 1/v \simeq 1.4644$. We also present a
LHV model for reproducing the statistics of arbitrary POVMs on the Werner state
for $v \simeq 0.4553$. The techniques we develop can be adapted to construct
LHV models for other entangled states, as well as bounding other Grothendieck
constants.


title:
Angular analyses of exclusive $\overline{B} \to X_J \ell_1 \ell_2$
  decays for spin $J \leq 4$

abstract:
  As an update to our previous calculation for spin $J\leq2$, we present the
angular moments for exclusive $\overline{B} \to X_J \ell_1 \ell_2$, where
$\ell_1$ is a charged massless lepton and $\ell_2$ is a charged or neutral
massless lepton, and $X_J$ is a mesonic system with spin $J\leq4$. The expected
applications include higher resonances in the $[K\pi]$ system in
$\overline{B}^0 \to K^- \pi^+ \mu^- \mu^+$ at LHCb in Run~II, and in the $[\pi
\pi]$ system for $ \overline{B} \to \pi \pi \ell^- \bar{\nu}_\ell$ at Belle~II.
For the $J\leq2$ case, we also provide a set of consistency relations among the
measured moments observables and validate them against the latest measurements
from LHCb.


title:
Nonequilibrium interpretation of DC properties of NbN superconducting
  hot electron bolometers

abstract:
  We present a physically consistent interpretation of the dc electrical
properties of niobiumnitride (NbN)-based superconducting hot-electron bolometer
(HEB-) mixers, using concepts of nonequilibrium superconductivity. Through this
we clarify what physical information can be extracted from the resistive
transition and the dc current-voltage characteristics, measured at suitably
chosen temperatures, and relevant for device characterization and optimization.
We point out that the intrinsic spatial variation of the electronic properties
of disordered superconductors, such as NbN, leads to a variation from device to
device.


title: Triply heavy tetraquark states with the $QQ\bar{Q}\bar{q}$ configuration

abstract:
  In the framework of the color-magnetic interaction, we systematically
investigate the mass splittings of the $QQ\bar{Q}\bar{q}$ tetraquark states and
estimated their rough masses in this work. These systems include the explicitly
exotic states $cc\bar{b}\bar{q}$ and $bb\bar{c}\bar{q}$ and the hidden exotic
states $cc\bar{c}\bar{q}$, $cb\bar{b}\bar{q}$, $bc\bar{c}\bar{q}$, and
$bb\bar{b}\bar{q}$. If a state around the estimated mass region could be
observed, its nature as a genuine tetraquark is favored. The strong decay
patterns shown here will be helpful to the experimental search for these exotic
states.


title:
Adaptive Decontamination of the Training Set: A Unified Formulation for
  Discriminative Visual Tracking

abstract:
  Tracking-by-detection methods have demonstrated competitive performance in
recent years. In these approaches, the tracking model heavily relies on the
quality of the training set. Due to the limited amount of labeled training
data, additional samples need to be extracted and labeled by the tracker
itself. This often leads to the inclusion of corrupted training samples, due to
occlusions, misalignments and other perturbations. Existing
tracking-by-detection methods either ignore this problem, or employ a separate
component for managing the training set.
  We propose a novel generic approach for alleviating the problem of corrupted
training samples in tracking-by-detection frameworks. Our approach dynamically
manages the training set by estimating the quality of the samples. Contrary to
existing approaches, we propose a unified formulation by minimizing a single
loss over both the target appearance model and the sample quality weights. The
joint formulation enables corrupted samples to be down-weighted while
increasing the impact of correct ones. Experiments are performed on three
benchmarks: OTB-2015 with 100 videos, VOT-2015 with 60 videos, and Temple-Color
with 128 videos. On the OTB-2015, our unified formulation significantly
improves the baseline, with a gain of 3.8% in mean overlap precision. Finally,
our method achieves state-of-the-art results on all three datasets. Code and
supplementary material are available at
http://www.cvl.isy.liu.se/research/objrec/visualtracking/decontrack/index.html .


title:
FastBDT: A speed-optimized and cache-friendly implementation of
  stochastic gradient-boosted decision trees for multivariate classification

abstract:
  Stochastic gradient-boosted decision trees are widely employed for
multivariate classification and regression tasks. This paper presents a
speed-optimized and cache-friendly implementation for multivariate
classification called FastBDT. FastBDT is one order of magnitude faster during
the fitting-phase and application-phase, in comparison with popular
implementations in software frameworks like TMVA, scikit-learn and XGBoost. The
concepts used to optimize the execution time and performance studies are
discussed in detail in this paper. The key ideas include: An equal-frequency
binning on the input data, which allows replacing expensive floating-point with
integer operations, while at the same time increasing the quality of the
classification; a cache-friendly linear access pattern to the input data, in
contrast to usual implementations, which exhibit a random access pattern.
FastBDT provides interfaces to C/C++, Python and TMVA. It is extensively used
in the field of high energy physics by the Belle II experiment.


title: ExoMol line lists XVIII. The high temperature spectrum of VO

abstract:
  An accurate line list, VOMYT, of spectroscopic transitions is presented for
hot VO. The 13 lowest electronic states are considered. Curves and couplings
are based on initial {\it ab initio} electronic structure calculations and then
tuned using available experimental data. Dipole moment curves, used to obtain
transition intensities, are computed using high levels of theory (e.g.
MRCI/aug-cc-pVQZ using state-specific or minimal-state CAS for dipole moments).
This line list contains over 277 million transitions between almost 640,000
energy levels. It covers the wavelengths longer than 0.29 $\mu$m and includes
all transitions from energy levels within the lowest nine electronic states
which have energies less than 20,000 \cm{} to upper states within the lowest 13
electronic states which have energies below 50,000 \cm{}. The line lists give
significantly increased absorption at infrared wavelengths compared to
currently available VO line lists. The full line lists is made available in
electronic form via the CDS database and at www.exomol.com.


title: Superconducting phase in the BCS model with imaginary magnetic field

abstract:
  We prove that in the reduced quartic BCS model with an imaginary external
magnetic field a spontaneous U(1)-symmetry breaking (SSB) and an off-diagonal
long range order (ODLRO) occur. The system is defined on a hyper-cubic lattice
with periodic boundary conditions at positive temperature. In the free part of
the Hamiltonian we assume the nearest-neighbor hopping. The chemical potential
is fixed so that the free Fermi surface does not degenerate. The term
representing the interaction between electrons' spin and the imaginary external
magnetic field is the z-component of the spin operator multiplied by a pure
imaginary parameter. The SSB and the ODLRO are shown in the infinite-volume
limit of the thermal average over the full Fermionic Fock space. The magnitude
of the negative coupling constant must be larger than a certain value so that
the gap equation is solvable. The gap equation is different from that of the
conventional mean field BCS model because of the presence of the imaginary
magnetic field. By adjusting the imaginary magnetic field this model shows the
SSB and the ODLRO in high temperature, weak coupling regimes where the
conventional reduced BCS model does not show these phenomena. The proof is
based on Grassmann Gaussian integral formulations and a double-scale
integration scheme to analytically control the formulations.


title:
Fluorescence via Reverse Intersystem Crossing from Higher Triplet States
  in a Bisanthracene Derivative

abstract:
  To elucidate the high external quantum efficiency observed for organic
light-emitting diodes using a bisanthracene derivative, BD1, as the emitting
molecule, off-diagonal vibronic coupling constants (VCCs) between the excited
states of BD1, which govern non-radiative transition rates, were calculated
employing time-dependent density functional theory. The VCCs were analysed
based on the concept of vibronic coupling density. The VCC calculations suggest
a fluorescence via higher triplets (FvHT) mechanism, which entails the
conversion of a T$_4$ exciton generated during electrical excitation into an
S$_2$ exciton via reverse intersystem crossing (RISC); moreover, the S$_2$
exciton relaxes to a fluorescent S$_1$ exciton because of large vibronic
coupling between S$_2$ and S$_1$. This mechanism is valid as long as the
relaxation of triplet states higher than T$_1$ to lower states is suppressed.
The symmetry-controlled thermally activated delayed fluorescence (SC-TADF) and
inverted singlet and triplet (iST) structure, which have been proposed in our
previous studies, are the special examples of the FvHT mechanism that need high
molecular symmetry. However, BD1 achieves the FvHT mechanism in spite of its
asymmetrical structure. A general condition for the suppression of radiative
and non-radiative transitions in molecules with pseudo-degenerate electronic
structures such as BD1 is discussed. A superordinate concept, fluorescence via
RISC, which includes TADF, SC-TADF, iST structure, and FvHT is also proposed.


title: Continuous-wave Raman Lasing in Aluminum Nitride Microresonators

abstract:
  We report the first investigation on continuous-wave Raman lasing in
high-quality-factor aluminum nitride (AlN) microring resonators. Although
wurtzite AlN is known to exhibit six Raman-active phonons, single-mode Raman
lasing with low threshold and high slope efficiency is demonstrated. Selective
excitation of A$_1^\mathrm{TO}$ and E$_2^\mathrm{high}$ phonons with Raman
shifts of $\sim$612 and 660 cm$^{-1}$ is observed by adjusting the polarization
of the pump light. A theoretical analysis of Raman scattering efficiency within
${c}$-plane (0001) of AlN is carried out to help account for the observed
lasing behavior. Bidirectional lasing is experimentally confirmed as a result
of symmetric Raman gain in micro-scale waveguides. Furthermore, second-order
Raman lasing with unparalleled output power of $\sim$11.3 mW is obtained, which
offers the capability to yield higher order Raman lasers for mid-infrared
applications.


title: The Complexity of Flat Freeze LTL

abstract:
  We consider the model-checking problem for freeze LTL on one-counter automata
(OCA). Freeze LTL extends LTL with the freeze quantifier, which allows one to
store different counter values of a run in registers so that they can be
compared with one another. As the model-checking problem is undecidable in
general, we focus on the flat fragment of freeze LTL, in which the usage of the
freeze quantifier is restricted. In a previous work, Lechner et al. showed that
model checking for flat freeze LTL on OCA with binary encoding of counter
updates is decidable and in 2NEXPTIME. In this paper, we prove that the problem
is, in fact, NEXPTIME-complete no matter whether counter updates are encoded in
unary or binary. Like Lechner et al., we rely on a reduction to the
reachability problem in OCA with parameterized tests (OCA(P)). The new aspect
is that we simulate OCA(P) by alternating two-way automata over words. This
implies an exponential upper bound on the parameter values that we exploit
towards an NP algorithm for reachability in OCA(P) with unary updates. We
obtain our main result as a corollary. As another application, relying on a
reduction by Bundala and Ouaknine, one obtains an alternative proof of the
known fact that reachability in closed parametric timed automata with one
parametric clock is in NEXPTIME.


title:
Positive Ricci curvature on simply-connected manifolds with
  cohomogeneity-two torus actions

abstract:
  A gap in the proof of the main result in reference [1] in our original
submission propagated into the constructions presented in the first version of
our manuscript. In this version we give an alternative proof for the existence
of Riemannian metrics with positive Ricci curvature on an infinite subfamily of
closed, simply-connected smooth manifolds with a cohomogeneity two torus action
and recover some of our original results.
  Namely, we show that, for each $n\geqslant 1$, there exist infinitely many
spin and non-spin diffeomorphism types of closed, smooth, simply-connected
$(n+4)$-manifolds with a smooth, effective action of a torus $T^{n+2}$ and a
metric of positive Ricci curvature invariant under a $T^{n}$-subgroup of
$T^{n+2}$. As an application, we show that every closed, smooth,
simply-connected $5$- and $6$-manifold admitting a smooth, effective torus
action of cohomogeneity two supports metrics with positive Ricci curvature.


title: Device-Independent Bounds on Detection Efficiency

abstract:
  In many quantum information applications, a minimum detection efficiency must
be exceeded to ensure success. Protocols depending on the violation of a Bell
inequality, for instance, may be subject to the so-called detection loophole:
imperfect detectors may yield spurious violations, which consequently cannot be
used to ensure, say, quantum cryptographic security. Hence, we investigate the
possibility of giving lower bounds on detector efficiency even if an adversary
has full control over both the source and the detectors. To this end, we
present a technique to systematically derive Bell inequalities free from the
detection loophole using only the observed measurements statistics. The
violation of these inequalities certifies that the detectors used exceed a
certain minimal efficiency.


title: A framework for mining process models from emails logs

abstract:
  Due to its wide use in personal, but most importantly, professional contexts,
email represents a valuable source of information that can be harvested for
understanding, reengineering and repurposing undocumented business processes of
companies and institutions. Towards this aim, a few researchers investigated
the problem of extracting process oriented information from email logs in order
to take benefit of the many available process mining techniques and tools. In
this paper we go further in this direction, by proposing a new method for
mining process models from email logs that leverage unsupervised machine
learning techniques with little human involvement. Moreover, our method allows
to semi-automatically label emails with activity names, that can be used for
activity recognition in new incoming emails. A use case demonstrates the
usefulness of the proposed solution using a modest in size, yet real-world,
dataset containing emails that belong to two different process models.


title:
Total Absorption Gamma-Ray Spectroscopy of 87Br, 88Br and 94Rb
  Beta-Delayed Neutron Emitters

abstract:
  We investigate the decay of 87Br, 88Br and 94Rb using total absorption
gamma-ray spectroscopy. These important fission products are beta-delayed
neutron emitters. Our data show considerable gamma-intensity, so far unobserved
in high-resolution gamma-ray spectroscopy, from states at high excitation
energy. We also find significant differences with the beta intensity that can
be deduced from existing measurements of the beta spectrum. We evaluate the
impact of the present data on reactor decay heat using summation calculations.
Although the effect is relatively small it helps to reduce the discrepancy
between calculations and integral measurements of the photon component for 235U
fission at cooling times in the range 1 to 100 s. We also use summation
calculations to evaluate the impact of present data on reactor antineutrino
spectra. We find a significant effect at antineutrino energies in the range of
5 to 9 MeV. In addition, we observe an unexpected strong probability for gamma
emission from neutron unbound states populated in the daughter nucleus. The
gamma branching is compared to Hauser-Feshbach calculations which allow one to
explain the large value for bromine isotopes as due to nuclear structure.
However the branching for 94Rb, although much smaller, hints of the need to
increase the radiative width by one order-of-magnitude. This leads to a similar
increase in the calculated (n,gamma) cross section for this very neutron-rich
nucleus with a potential impact on r-process abundance calculations.


title: On the surface physics affecting solar oscillation frequencies

abstract:
  Adiabatic oscillation frequencies of stellar models, computed with the
standard mixing-length formulation for convection, increasingly deviate with
radial order from observations in solar-like stars. Standard solar models
overestimate adiabatic frequencies by as much as ~ 20 {\mu}Hz. In this letter,
we address the physical processes of turbulent convection that are
predominantly responsible for the frequency differences between standard models
and observations, also called `surface effects'. We compare measured solar
frequencies from the MDI instrument on the SOHO spacecraft with frequency
calculations that include three-dimensional (3D) hydrodynamical simulation
results in the equilibrium model, nonadiabatic effects, and a consistent
treatment of the turbulent pressure in both the equilibrium and stability
computations. With the consistent inclusion of the above physics in our model
computation we are able to reproduce the observed solar frequencies to < 3
{\mu}Hz without the need of any additional ad-hoc functional corrections.


title: Rethinking Newton's $\textit{Principia}$

abstract:
  It is widely accepted that the notion of an inertial frame is central to
Newtonian mechanics and that the correct space-time structure underlying
$\text{Newton's}$ methods in $\textit{Principia}$ is neo-Newtonian or Galilean
space-time. I argue to the contrary that inertial frames are not needed in
$\text{Newton's}$ theory of motion, and that the right space-time structure for
$\text{Newton's}$ $\textit{Principia}$ requires the notion of parallelism of
spatial directions at different times and nothing more.


title:
Magnon nodal-line semimetals and drumhead surface states in anisotropic
  pyrochlore ferromagnets

abstract:
  We introduce a new type of topological magnon matter: the magnonic pendant to
electronic nodal-line semimetals. Magnon spectra of anisotropic pyrochlore
ferromagnets feature twofold degeneracies of magnon bands along a closed loop
in reciprocal space. These magnon nodal lines are topologically protected by
the coexistence of inversion and time-reversal symmetry; they require the
absence of spin-orbit interaction (no Dzyaloshinskii-Moriya interaction). We
calculate the topological invariants of the nodal lines and show that details
of the associated magnon drumhead surface states depend strongly on the
termination of the surface. Magnon nodal-line semimetals complete the family of
topological magnons in three-dimensional ferromagnetic materials.


title:
Topology of the Milnor fibrations of polar weighted homogeneous
  polynomials

abstract:
  In the present paper, we study deformations of polar weighted homogeneous
polynomials which are also polar weighted homogeneous polynomials. We describe
a round handle decomposition of the Milnor fibration of a deformation of a
polar weighted homogeneous polynomial concretely and give the number of round
handles by the number of positive and negative components of the links of
singularities appearing before and after the deformation. We also give a
formula of characteristic polynomials of these singularities by using the
decomposition of the monodromy of the Milnor fibration induced by a round
handle decomposition.


title: On a two-phase problem for harmonic measure in general domains

abstract:
  We show that, for disjoint domains in the Euclidean space, mutual absolute
continuity of their harmonic measures implies absolute continuity with respect
to surface measure and rectifiability in the intersection of their boundaries.
This improves on our previous result which assumed that the boundaries
satisfied the capacity density condition.


title:
Subtraction of power counting breaking terms in chiral perturbation
  theory: spinless matter fields

abstract:
  When matter fields are included in chiral perturbation theory, the
nonvanishing mass in the chiral limit introduces a new energy scale so that the
loop diagrams including such matter field propagators spoil the usual power
counting. However, the power counting breaking terms can be absorbed into
counterterms in the chiral Lagrangian. In this paper, we systematically derive
these terms to leading one-loop order (next-to-next-to leading order in the
chiral expansion) at once by calculating the generating functional using the
path integral. They are then absorbed by counterterms in the next-to-leading
order Lagrangian. The method can be extended to calculating power counting
breaking terms for other matter fields.


title:
Retrodiction of a sequence of measurement results in qubit
  interferometers

abstract:
  We study how well we can retrodict results of measurements made on a quantum
system if we can make measurements on its final state. We know what
measurements were made, but not their results. An initial examination shows
that we can gain anywhere from no information to perfect information about the
results of previous measurements, depending on the measurements and the initial
state of the system. The case of two two-outcome measurements, the second of
which is a projective measurement, is examined in some detail. We then look at
a model of a qubit interferometer in which measurements are made in order to
determine the path the qubit followed. The measurement made on the final state
of the qubit depends on the information about previous measurement results that
we are trying to determine. One can attempt to find the result of just one of
the measurements, all of them, or find a measurement sequence that was not
realized. We study all three possibilities.


title: On the dynamics of floating structures

abstract:
  This paper addresses the floating body problem which consists in studying the
interaction of surface water waves with a floating body. We propose a new
formulation of the water waves problem that can easily be generalized in order
to take into account the presence of a floating body. The resulting equations
have a compressible-incompressible structure in which the interior pressure
exerted by the fluid on the floating body is a Lagrange multiplier that can be
determined through the resolution of a $d$-dimensional elliptic equation, where
$d$ is the horizontal dimension. In the case where the object is freely
floating, we decompose the hydrodynamic force and torque exerted by the fluid
on the solid in order to exhibit an added mass effect; in the one dimensional
case $d=1$, the computations can be carried out explicitly. We also show that
this approach in which the interior pressure appears as a Lagrange multiplier
can be implemented on reduced asymptotic models such as the nonlinear shallow
water equations and the Boussinesq equations; we also show that it can be
transposed to the discrete version of these reduced models and propose simple
numerical schemes in the one dimensional case. We finally present several
numerical computations based on these numerical schemes; in order to validate
these computations we exhibit explicit solutions in some particular
configurations such as the return to equilibrium problem in which an object is
dropped from a non-equilibrium position in a fluid which is initially at rest.

categories: math.AP math.NA physics.ao-ph physics.flu-dyn


title:
Multiband nodeless superconductivity near the charge-density-wave
  quantum critical point in ZrTe3-xSex

abstract:
  Recently it was found that selenium doping can suppress the
charge-density-wave (CDW) order and induce bulk superconductivity in ZrTe$_3$.
The observed superconducting dome suggests the existence of a CDW quantum
critical point (QCP) in ZrTe$_{3-x}$Se$_x$ near $x \approx$ 0.04. To elucidate
its superconducting state near the CDW QCP, we measure the thermal conductivity
of two ZrTe$_{3-x}$Se$_x$ single crystals ($x$ = 0.044 and 0.051) down to 80
mK. For both samples, the residual linear term $\kappa_0/T$ at zero field is
negligible, which is a clear evidence for nodeless superconducting gap.
Furthermore, the field dependence of $\kappa_0/T$ manifests multigap behavior.
These results demonstrate multiple nodeless superconducting gaps in
ZrTe$_{3-x}$Se$_x$, which indicates conventional superconductivity despite of
the existence of a CDW QCP.


title: DustPedia - A Definitive Study of Cosmic Dust in the Local Universe

abstract:
  The European Space Agency has invested heavily in two cornerstones missions;
Herschel and Planck. The legacy data from these missions provides us with an
unprecedented opportunity to study cosmic dust in galaxies so that we can
answer fundamental questions about, for example: the origin of the chemical
elements, physical processes in the interstellar medium (ISM), its effect on
stellar radiation, its relation to star formation and how this relates to the
cosmic far infrared background. In this paper we describe the DustPedia
project, which is enabling us to develop tools and computer models that will
help us relate observed cosmic dust emission to its physical properties
(chemical composition, size distribution, temperature), to its origins (evolved
stars, super novae, growth in the ISM) and the processes that destroy it (high
energy collisions and shock heated gas). To carry out this research we will
combine the Herschel/Planck data with that from other sources of data,
providing observations at numerous wavelengths (< 41) across the spectral
energy distribution, thus creating the DustPedia database. To maximise our
spatial resolution and sensitivity to cosmic dust we limit our analysis to 4231
local galaxies (v < 3000 km/s) selected via their near infrared luminosity
(stellar mass). To help us interpret the data we have developed a new physical
model for dust (THEMIS), a new Bayesian method of fitting and interpreting
spectral energy distributions (HerBIE) and a state-of-the-art Monte Carlo
photon tracing radiative transfer model (SKIRT). In this the first of the
DustPedia papers we describe the project objectives, data sets used and provide
an insight into the new scientific methods we plan to implement.


title:
Simulating positive-operator-valued measures with projective
  measurements

abstract:
  Standard projective measurements represent a subset of all possible
measurements in quantum physics, defined by positive-operator-valued measures.
We study what quantum measurements are projective simulable, that is, can be
simulated by using projective measurements and classical randomness. We first
prove that every measurement on a given quantum system can be realised by
classical processing of projective measurements on the system plus an ancilla
of the same dimension. Then, given a general measurement in dimension two or
three, we show that deciding whether it is projective-simulable can be solved
by means of semi-definite programming. We also establish conditions for the
simulation of measurements using projective ones valid for any dimension. As an
application of our formalism, we improve the range of visibilities for which
two-qubit Werner states do not violate any Bell inequality for all
measurements. From an implementation point of view, our work provides bounds on
the amount of noise a measurement tolerates before losing any advantage over
projective ones.


title:
Inertial particles distribute in turbulence as Poissonian points with
  random intensity inducing clustering and supervoiding

abstract:
  This work considers the distribution of inertial particles in turbulence
using the point-particle approximation. We demonstrate that the random point
process formed by the positions of particles in space is a Poisson point
process with log-normal random intensity ("log Gaussian Cox process" or LGCP).
The probability of having a finite number of particles in a small volume is
given in terms of the characteristic function of a log-normal distribution.
Corrections due to discreteness of the number of particles to the previously
derived statistics of particle concentration in the continuum limit are
provided. These are relevant for dealing with experimental or numerical data.
The probability of having regions without particles, i.e. voids, is larger for
inertial particles than for tracer particles where voids are distributed
according to Poisson processes. Further, the probability of having large voids
decays only log-normally with size. This shows that particles cluster, leaving
voids behind. At scales where there is no clustering there can still be an
increase of the void probability so that turbulent voiding is stronger than
clustering. The demonstrated double stochasticity of the distribution
originates in the two-step formation of fluctuations. First, turbulence brings
the particles randomly close together which happens with Poisson-type
probability. Then, turbulence compresses the particles' volume in the
observation volume. We confirm the theory of the statistics of the number of
particles in small volumes by numerical observations of inertial particle
motion in a chaotic ABC flow. The improved understanding of clustering
processes can be applied to predict the long-time survival probability of
reacting particles. Our work implies that the particle distribution in weakly
compressible flow with finite time correlations is a LGCP, independently of the
details of the flow statistics.


title: Discriminative Scale Space Tracking

abstract:
  Accurate scale estimation of a target is a challenging research problem in
visual object tracking. Most state-of-the-art methods employ an exhaustive
scale search to estimate the target size. The exhaustive search strategy is
computationally expensive and struggles when encountered with large scale
variations. This paper investigates the problem of accurate and robust scale
estimation in a tracking-by-detection framework. We propose a novel scale
adaptive tracking approach by learning separate discriminative correlation
filters for translation and scale estimation. The explicit scale filter is
learned online using the target appearance sampled at a set of different
scales. Contrary to standard approaches, our method directly learns the
appearance change induced by variations in the target scale. Additionally, we
investigate strategies to reduce the computational cost of our approach.
  Extensive experiments are performed on the OTB and the VOT2014 datasets.
Compared to the standard exhaustive scale search, our approach achieves a gain
of 2.5% in average overlap precision on the OTB dataset. Additionally, our
method is computationally efficient, operating at a 50% higher frame rate
compared to the exhaustive scale search. Our method obtains the top rank in
performance by outperforming 19 state-of-the-art trackers on OTB and 37
state-of-the-art trackers on VOT2014.


title: On-sky tests of sky-subtraction methods for fiber-fed spectrographs

abstract:
  We present preliminary results on on-sky test of sky subtraction methods for
fiber-fed spectrograph. Using dedicated observation with FLAMES/VLT in I-band,
we have tested the accuracy of the sky subtraction for 4 sky subtraction
methods: mean sky, closest sky, dual stare and cross-beam switching. The cross
beam-switching and dual stare method reach accuracy and precision of the sky
subtraction under 1%. In contrast to the commonly held view in the literature,
this result points out that fiber-fed spectrographs are adapted for the
observations of faint targets.


title:
Using Gaussian processes to model light curves in the presence of
  flickering: the eclipsing cataclysmic variable ASASSN-14ag

abstract:
  The majority of cataclysmic variable (CV) stars contain a stochastic noise
component in their light curves, commonly referred to as flickering. This can
significantly affect the morphology of CV eclipses and increases the difficulty
in obtaining accurate system parameters with reliable errors through eclipse
modelling. Here we introduce a new approach to eclipse modelling, which models
CV flickering with the help of Gaussian processes (GPs). A parameterised
eclipse model - with an additional GP component - is simultaneously fit to 8
eclipses of the dwarf nova ASASSN-14ag and system parameters determined. We
obtain a mass ratio $q$ = 0.149 $\pm$ 0.016 and inclination $i$ = 83.4
$^{+0.9}_{-0.6}$ $^{\circ}$. The white dwarf and donor masses were found to be
$M_{w}$ = 0.63 $\pm$ 0.04 $M_{\odot}$ and $M_{d}$ = 0.093 $^{+0.015}_{-0.012}$
$M_{\odot}$, respectively. A white dwarf temperature $T_{w}$ = 14000
$^{+2200}_{-2000}$ K and distance $d$ = 146 $^{+24}_{-20}$ pc were determined
through multicolour photometry. We find GPs to be an effective way of modelling
flickering in CV light curves and plan to use this new eclipse modelling
approach going forward.


title: Multilevel Monte Carlo for Scalable Bayesian Computations

abstract:
  Markov chain Monte Carlo (MCMC) algorithms are ubiquitous in Bayesian
computations. However, they need to access the full data set in order to
evaluate the posterior density at every step of the algorithm. This results in
a great computational burden in big data applications. In contrast to MCMC
methods, Stochastic Gradient MCMC (SGMCMC) algorithms such as the Stochastic
Gradient Langevin Dynamics (SGLD) only require access to a batch of the data
set at every step. This drastically improves the computational performance and
scales well to large data sets. However, the difficulty with SGMCMC algorithms
comes from the sensitivity to its parameters which are notoriously difficult to
tune. Moreover, the Root Mean Square Error (RMSE) scales as
$\mathcal{O}(c^{-\frac{1}{3}})$ as opposed to standard MCMC
$\mathcal{O}(c^{-\frac{1}{2}})$ where $c$ is the computational cost.
  We introduce a new class of Multilevel Stochastic Gradient Markov chain Monte
Carlo algorithms that are able to mitigate the problem of tuning the step size
and more importantly of recovering the $\mathcal{O}(c^{-\frac{1}{2}})$
convergence of standard Markov Chain Monte Carlo methods without the need to
introduce Metropolis-Hasting steps. A further advantage of this new class of
algorithms is that it can easily be parallelised over a heterogeneous computer
architecture. We illustrate our methodology using Bayesian logistic regression
and provide numerical evidence that for a prescribed relative RMSE the
computational cost is sublinear in the number of data items.


title: Quantifying Heteroskedasticity via Bhattacharyya Distance

abstract:
  Heteroskedasticity is a statistical anomaly that describes differing
variances of error terms in a time series dataset. The presence of
heteroskedasticity in data imposes serious challenges for forecasting models
and many statistical tests are not valid in the presence of heteroskedasticity.
Heteroskedasticity of the data affects the relation between the predictor
variable and the outcome, which leads to false positive and false negative
decisions in the hypothesis testing. Available approaches to study
heteroskedasticity thus far adopt the strategy of accommodating
heteroskedasticity in the time series and consider it an inevitable source of
noise. In these existing approaches, two forecasting models are prepared for
normal and heteroskedastic scenarios and a statistical test is to determine
whether or not the data is heteroskedastic.
  This work-in-progress research introduces a quantifying measurement for
heteroskedasticity. The idea behind the proposed metric is the fact that a
heteroskedastic time series features a uniformly distributed local variances.
The proposed measurement is obtained by calculating the local variances using
linear time invariant filters. A probability density function of the calculated
local variances is then derived and compared to a uniform distribution of
theoretical ultimate heteroskedasticity using statistical divergence
measurements. The results demonstrated on synthetic datasets shows a strong
correlation between the proposed metric and number of variances locally
estimated in a heteroskedastic time series.


title: mlr Tutorial

abstract:
  This document provides and in-depth introduction to the mlr framework for
machine learning experiments in R.


title: The complexity of perfect matchings and packings in dense hypergraphs

abstract:
  Given two $k$-graphs $H$ and $F$, a perfect $F$-packing in $H$ is a
collection of vertex-disjoint copies of $F$ in $H$ which together cover all the
vertices in $H$. In the case when $F$ is a single edge, a perfect $F$-packing
is simply a perfect matching. For a given fixed $F$, it is often the case that
the decision problem whether an $n$-vertex $k$-graph $H$ contains a perfect
$F$-packing is NP-complete. Indeed, if $k \geq 3$, the corresponding problem
for perfect matchings is NP-complete whilst if $k=2$ the problem is NP-complete
in the case when $F$ has a component consisting of at least $3$ vertices.
  In this paper we give a general tool which can be used to determine classes
of (hyper)graphs for which the corresponding decision problem for perfect
$F$-packings is polynomial time solvable. We then give three applications of
this tool: (i) Given $1\leq \ell \leq k-1$, we give a minimum $\ell$-degree
condition for which it is polynomial time solvable to determine whether a
$k$-graph satisfying this condition has a perfect matching; (ii) Given any
graph $F$ we give a minimum degree condition for which it is polynomial time
solvable to determine whether a graph satisfying this condition has a perfect
$F$-packing; (iii) We also prove a similar result for perfect $K$-packings in
$k$-graphs where $K$ is a $k$-partite $k$-graph.
  For a range of values of $\ell,k$ (i) resolves a conjecture of Keevash, Knox
and Mycroft whilst (ii) answers a question of Yuster in the negative. In many
cases our results are best possible in the sense that lowering the minimum
degree condition means that the corresponding decision problem becomes
NP-complete.


title: Exoplanetary Detection By Multifractal Spectral Analysis

abstract:
  Owing to technological advances, the number of exoplanets discovered has
risen dramatically in the last few years. However, when trying to observe Earth
analogs, it is often difficult to test the veracity of detection. We have
developed a new approach to the analysis of exoplanetary spectral observations
based on temporal multifractality, which identifies time scales that
characterize planetary orbital motion around the host star, and those that
arise from stellar features such as spots. Without fitting stellar models to
spectral data, we show how the planetary signal can be robustly detected from
noisy data using noise amplitude as a source of information. For observation of
transiting planets, combining this method with simple geometry allows us to
relate the time scales obtained to primary and secondary eclipse of the
exoplanets. Making use of data obtained with ground-based and space-based
observations we have tested our approach on HD 189733b. Moreover, we have
investigated the use of this technique in measuring planetary orbital motion
via Doppler shift detection. Finally, we have analyzed synthetic spectra
obtained using the SOAP 2.0 tool, which simulates a stellar spectrum and the
influence of the presence of a planet or a spot on that spectrum over one
orbital period. We have demonstrated that, so long as the signal-to-noise-ratio
$\ge$ 75, our approach reconstructs the planetary orbital period, as well as
the rotation period of a spot on the stellar surface.

categories: astro-ph.EP astro-ph.SR physics.comp-ph physics.space-ph


title:
Giant Rashba effect at the topological surface of PrGe revealing
  antiferromagnetic spintronics

abstract:
  Rashba spin-orbit splitting in the magnetic materials opens up a new
perspective in the field of spintronics. Here, we report a giant Rashba-type
spin-orbit effect on PrGe [010] surface in the paramagnetic phase with Rashba
coefficient {\alpha}_R=5 eV{\AA}. Significant changes in the electronic band
structure has been observed across the phase transitions from paramagnetic to
antiferromagnetic (44 K) and from antiferromagnetic to the ferromagnetic ground
state (41.5 K). We find that Pr 4f states in PrGe is strongly hybridized with
the Pr 5d and Ge 4s-4p states near the Fermi level. The behavior of Rashba
effect is found to be different in the k_x and the k_y directions showing
electron-like and the hole-like bands, respectively. The possible origin of
Rashba effect in the paramagnetic phase is related to the anti-parallel spin
polarization present in this system. First-principles density functional
calculations of Pr terminated surface with the anti-parallel spins shows a fair
agreement with the experimental results. We find that the anti-parallel spins
are strongly coupled to the lattice such that the PrGe system behaves like weak
ferromagnetic system. Analysis of the energy dispersion curves at different
magnetic phases showed that there is a competition between the
Dzyaloshinsky-Moriya interaction and the exchange interaction which gives rise
to the magnetic ordering in PrGe. Supporting evidences of the presence of
Dzyaloshinsky-Moriya interaction are observed as anisotropic magnetoresistance
with respect to field direction and first-order type hysteresis in the X-ray
diffraction measurements. A giant negative magnetoresistance of 43% in the
antiferromagnetic phase and tunable Rashba parameter with temperature across
the magnetic transitions makes this material a suitable candidate for
technological application in the antiferromagnetic spintronic devices.


title:
Effect of strain, thickness, and local surface environment on electron
  transport properties of oxygen-terminated copper thin films

abstract:
  Electron transport is studied in surface oxidized single-crystal copper thin
films with a thickness of up to 5.6 nm by applying density functional theory
and density functional tight binding methods to determine electron transport
properties within the ballistic regime. The variation of the electron
transmission as a function of film thickness as well as the different
contributions to the overall electron transmission as a function of depth into
the the films is examined. Transmission at the oxidized copper film surfaces is
found to be universally low. Films with thickness greater than 2.7 nm exhibit a
similar behavior in local transmission per unit area with depth from the film
surface; transmission per unit area initially increases rapidly and then
plateaus at a depth of approximately 0.35-0.5 nm away from the surface,
dependent on surface facet. Unstrained films tend to exhibit a higher
transmission per unit area than corresponding films under tensile strain.


title: Vector orthogonal polynomials with Bochner's property

abstract:
  Classical orthogonal polynomial systems of Jacobi, Hermite, Laguerre and
Bessel have the property that the polynomials of each system are eigenfunctions
of a second order ordinary differential operator. According to a classical
theorem by Bochner they are the only systems with this property. Similarly, the
polynomials of Charlier, Meixner, Kravchuk and Hahn are both orthogonal and are
eigenfunctions of a suitable difference operator of second order. We recall
that according to the famous theorem of Favard-Shohat, the condition of
orthogonality is equivalent to the 3-term recurrence relation. Vector
orthogonal polynomials (VOP) satisfy finite-term recurrence relation with more
terms, according to a theorem by J. Van Iseghem and this characterizes them.
  Motivated by Bochner's theorem we are looking for VOP that are also
eigenfunctions of a differential (difference) operator. We call these
simultaneous conditions Bochner's property.
  The goal of this paper is to introduce methods for construction of VOP which
have Bochner's property. The methods are purely algebraic and are based on
automorphisms of non-commutative algebras. They also use ideas from the so
called bispectral problem. Applications of the abstract methods include broad
generalizations of the classical orthogonal polynomials, both continuous and
discrete. Other results connect different families of VOP, including the
classical ones, by linear transforms of purely algebraic origin, despite of the
fact that, when interpreted analytically, they are integral transformations.


title: Science with MATISSE

abstract:
  We present an overview of the scientific potential of MATISSE, the Multi
Aperture mid-Infrared SpectroScopic Experiment for the Very Large Telescope
Interferometer. For this purpose we outline selected case studies from various
areas, such as star and planet formation, active galactic nuclei, evolved
stars, extrasolar planets, and solar system minor bodies and discuss strategies
for the planning and analysis of future MATISSE observations. Moreover, the
importance of MATISSE observations in the context of complementary high-angular
resolution observations at near-infrared and submillimeter/millimeter
wavelengths is highlighted.


title:
Uncertainty Analysis of Simple Macroeconomic Models Using Angel-Daemon
  Games

abstract:
  We propose the use of an angel-daemon framework to perform an uncertainty
analysis of short-term macroeconomic models with exogenous components. An
uncertainty profile $\mathcal U$ is a short and macroscopic description of a
potentially perturbed situation. The angel-daemon framework uses $\mathcal U$
to define a strategic game where two agents, the angel and the daemon, act
selfishly having different goals. The Nash equilibria of those games provide
the stable strategies in perturbed situations, giving a natural estimation of
uncertainty.
  In this initial work we apply the framework in order to get an uncertainty
analysis of linear versions of the IS-LM and the IS-MP models. In those models,
by considering uncertainty profiles, we can capture different economical
situations. Some of them can be described in terms of macroeconomic policy
coordination. In other cases we just analyse the results of the system under
some possible perturbation level. Besides providing examples of application we
analyse the structure of the Nash equilibria in some particular cases of
interest.


title: XENON100 Dark Matter Results from a Combination of 477 Live Days

abstract:
  We report on WIMP search results of the XENON100 experiment, combining three
runs summing up to 477 live days from January 2010 to January 2014. Data from
the first two runs were already published. A blind analysis was applied to the
last run recorded between April 2013 and January 2014 prior to combining the
results. The ultra-low electromagnetic background of the experiment, ~$5 \times
10^{-3}$ events/(keV$_{\mathrm{ee}}\times$kg$\times$day) before electronic
recoil rejection, together with the increased exposure of 48 kg $\times$ yr
improves the sensitivity. A profile likelihood analysis using an energy range
of (6.6 - 43.3) keV$_{\mathrm{nr}}$ sets a limit on the elastic,
spin-independent WIMP-nucleon scattering cross section for WIMP masses above 8
GeV/$c^2$, with a minimum of 1.1 $\times 10^{-45}$ cm$^2$ at 50 GeV/$c^2$ and
90% confidence level. We also report updated constraints on the elastic,
spin-dependent WIMP-nucleon cross sections obtained with the same data. We set
upper limits on the WIMP-neutron (proton) cross section with a minimum of 2.0
$\times 10^{-40}$ cm$^2$ (52$\times 10^{-40}$ cm$^2$) at a WIMP mass of 50
GeV/$c^2$, at 90% confidence level.


title:
Probing the scale invariance of the inflationary power spectrum in
  expanding quasi-two-dimensional dipolar condensates

abstract:
  We consider an analogue de Sitter cosmos in an expanding
quasi-two-dimensional Bose-Einstein condensate with dominant dipole-dipole
interactions between the atoms or molecules in the ultracold gas. It is
demonstrated that a hallmark signature of inflationary cosmology, the scale
invariance of the power spectrum of inflaton field correlations, experiences
strong modifications when, at the initial stage of expansion, the excitation
spectrum displays a roton minimum. Dipolar quantum gases thus furnish a viable
laboratory tool to experimentally investigate, with well-defined and
controllable initial conditions, whether primordial oscillation spectra
deviating from Lorentz invariance at trans-Planckian momenta violate standard
predictions of inflationary cosmology.


title:
Derandomized concentration bounds for polynomials, and hypergraph
  maximal independent set

abstract:
  A parallel algorithm for maximal independent set (MIS) in hypergraphs has
been a long-standing algorithmic challenge, dating back nearly 30 years to a
survey of Karp & Ramachandran (1990). The best randomized parallel algorithm
for hypergraphs of fixed rank $r$ was developed by Beame & Luby (1990) and
Kelsen (1992), running in time roughly $(\log n)^{r!}$.
  We improve the randomized algorithm of Kelsen, reducing the runtime to
roughly $(\log n)^{2^r}$ and simplifying the analysis through the use of
more-modern concentration inequalities. We also give a method for derandomizing
concentration bounds for low-degree polynomials, which are the key technical
tool used to analyze that algorithm. This leads to a deterministic PRAM
algorithm also running in $(\log n)^{2^{r+3}}$ time and $\text{poly}(m,n)$
processors. This is the first deterministic algorithm with sub-polynomial
runtime for hypergraphs of rank $r > 3$.
  Our analysis can also apply when $r$ is slowly growing; using this in
conjunction with a strategy of Bercea et al. (2015) gives a deterministic MIS
algorithm running in time $\exp(O( \frac{\log (mn)}{\log \log (mn)}))$.


title: $d$-Orthogonal Analogs of Classical Orthogonal Polynomials

abstract:
  Classical orthogonal polynomial systems of Jacobi, Hermite and Laguerre have
the property that the polynomials of each system are eigenfunctions of a second
order ordinary differential operator. According to a famous theorem by Bochner
they are the only systems on the real line with this property. Similar results
hold for the discrete orthogonal polynomials. In a recent paper we introduced a
natural class of polynomial systems whose members are the eigenfunctions of a
differential operator of higher order and which are orthogonal with respect to
d measures, rather than one. These polynomial systems, enjoy a number of
properties which make them a natural analog of the classical orthogonal
polynomials. In the present paper we continue their study. The most important
new properties are their hypergeometric representations which allow us to
derive their generating functions and in some cases also Mehler-Heine type
formulas.


title: The global formulation of generalized Einstein-Scalar-Maxwell theories

abstract:
  We summarize the global geometric formulation of Einstein-Scalar-Maxwell
theories twisted by flat symplectic vector bundle which encodes the duality
structure of the theory. We describe the scalar-electromagnetic symmetry group
of such models, which consists of flat unbased symplectic automorphisms of the
flat symplectic vector bundle lifting those isometries of the scalar manifold
which preserve the scalar potential. The Dirac quantization condition for such
models involves a local system of integral symplectic spaces, giving rise to a
bundle of polarized Abelian varieties equipped with a symplectic flat
connection, which is defined over the scalar manifold of the theory.
Generalized Einstein-Scalar-Maxwell models arise as the bosonic sector of the
effective theory of string/M-theory compactifications to four-dimensions, and
they are characterized by having non-trivial solutions of "U-fold" type.


title:
Steiljes electrostatic model with imaginary charges resolves
  wave-particle duality

abstract:
  In this paper, we show that the quantum bound state problems are mapped to
$N$ point vortices with the identical circulation or strength using the
Steiljes electrostatic model with imaginary charges. We also show that these
$N$ point charges or vortices, become imaginary, in a constant background field
will admit a wave solution under paraxial wave approximation. Therefore, in
quantum mechanics as long as paraxial approximation is valid it behaves like a
wave.


title: Electron transport properties of sub-3-nm diameter copper nanowires

abstract:
  Density functional theory and density functional tight-binding are applied to
model electron transport in copper nanowires of approximately 1 nm and 3 nm
diameters with varying crystal orientation and surface termination. The copper
nanowires studied are found to be metallic irrespective of diameter, crystal
orientation and/or surface termination. Electron transmission is highly
dependent on crystal orientation and surface termination. Nanowires oriented
along the [110] crystallographic axis consistently exhibit the highest electron
transmission while surface oxidized nanowires show significantly reduced
electron transmission compared to unterminated nanowires. Transmission per unit
area is calculated in each case, for a given crystal orientation we find that
this value decreases with diameter for unterminated nanowires but is largely
unaffected by diameter in surface oxidized nanowires for the size regime
considered. Transmission pathway plots show that transmission is larger at the
surface of unterminated nanowires than inside the nanowire and that
transmission at the nanowire surface is significantly reduced by surface
oxidation. Finally, we present a simple model which explains the transport per
unit area dependence on diameter based on transmission pathways results.


title: Self-Stabilizing Robots in Highly Dynamic Environments

abstract:
  This paper deals with the classical problem of exploring a ring by a cohort
of synchronous robots. We focus on the perpetual version of this problem in
which it is required that each node of the ring is visited by a robot
infinitely often. The challenge in this paper is twofold. First, we assume that
the robots evolve in a highly dynamic ring, \ie edges may appear and disappear
unpredictably without any recurrence, periodicity, nor stability assumption.
The only assumption we made (known as temporal connectivity assumption) is that
each node is infinitely often reachable from any other node. Second, we aim at
providing a self-stabilizing algorithm to the robots, i.e., the algorithm must
guarantee an eventual correct behavior regardless of the initial state and
positions of the robots.In this harsh environment, our contribution is to fully
characterize, for each size of the ring, the necessary and sufficient number of
robots to solve deterministically the problem.


title:
Averaged electron collision cross sections for thermal mixtures of
  $\alpha$-Alanine conformers in the gas phase

abstract:
  A theoretical study of elastic electron collisions with 9 conformers of the
gas-phase amino acid $\alpha$-alanine (CH$_3$CH(NH$_2$)COOH) is performed. The
eigenphase sums, resonance features, differential and integral cross sections
are computed for each individual conformer. Resonance positions for the
low-energy $\pi^*$ shape resonance are found to vary from 2.6 eV to 3.1 eV and
the resonance widths from 0.3 eV to 0.5 eV. Averaged cross sections for thermal
mixtures of the 9 conformers are presented. Both theoretical and experimental
population ratios are considered. Thermally-averaged cross sections obtained
using the best theoretical estimates give reasonable agreement with the
observed thermal cross sections. Excited conformers IIA and IIB make a large
contribution to this average due to their large permanent dipole moments.


title: The transport mechanism of the integer quantum Hall effect

abstract:
  The integer quantum Hall effect is analysed using a transport mechanism with
a semi-classic wave packages of electrons in this paper. A strong magnetic
field perpendicular to a slab separates the electron current into two branches
with opposite wave vectors $({\it k})$ and locating at the two edges of the
slab, respectively, along the current. In this case back scattering of
electrons ($k\rightarrow -k$) is prohibited by the separation of electron
currents. Thus the slab exhibits zero longitudinal resistance and plateaus of
Hall resistance. When the Fermi level is scanning over a Landau level when the
magnetic field increases, however, the electron waves locate around the central
axis of the slab and overlap each other thus back scattering of electrons takes
place frequently. Then longitudinal resistance appears and the Hall resistance
goes up from one plateau to a new plateau.


title:
Calculating the Finite-Speed-of-Light Effect in Atom Gravimeters with
  General Relativity

abstract:
  This work mainly presents a relativistic analytical calculating method for
the finite speed-of-light effect in atom gravimeters, which can simplify the
deriva- tion and give a more complete expression for the associated correction.


title:
At which magnetic field, exactly, does the Kondo resonance begin to
  split? A Fermi liquid description of the low-energy properties of the
  Anderson model

abstract:
  This paper is a corrected version of Phys. Rev. B 95, 165404 (2017), which we
have retracted because it contained a trivial but fatal sign error that lead to
incorrect conclusions. --- We extend a recently-eveloped Fermi-liquid (FL)
theory for the asymmetric single-impurity Anderson model [C. Mora $et al.$,
Phys. Rev. B, 92, 075120 (2015)] to the case of an arbitrary local magnetic
field. To describe the system's low-lying quasiparticle excitations for
arbitrary values of the bare Hamiltonian's model parameters, we construct an
effective low-energy FL Hamiltonian whose FL parameters are expressed in terms
of the local level's spin-dependent ground-state occupations and their
derivatives with respect to level energy and local magnetic field. These
quantities are calculable with excellent accuracy from the Bethe Ansatz
solution of the Anderson model. Applying this effective model to a quantum dot
in a nonequilibrium setting, we obtain exact results for the curvature of the
spectral function, $c_A$, describing its leading $\sim\varepsilon^2$ term, and
the transport coefficients $c_V$ and $c_T$, describing the leading $\sim V^2$
and $\sim T^2$ terms in the nonlinear differential conductance. A sign change
in $c_A$ or $c_V$ is indicative of a change from a local maximum to a local
minimum in the spectral function or nonlinear conductance, respectively, as is
expected to occur when an increasing magnetic field causes the Kondo resonance
to split into two subpeaks. We find that the fields $B_A$, $B_T$ and $B_V$ at
which $c_A$, $c_T$ and $c_V$ change sign, respectively, are all of order $T_K$,
as expected, with $B_A = B_T = B_V = 0.75073\,T_K$ in the Kondo limit.


title: The triviality of a certain invariant of link maps in the four-sphere

abstract:
  It is an open problem whether Kirk's $\sigma$ invariant is the complete
obstruction to a link map $S^2\cup S^2\to S^4$ being link homotopically
trivial. With the objective of constructing counterexamples, Li proposed a link
homotopy invariant $\omega$ that is defined on the kernel of $\sigma$ and also
obstructs link nullhomotopy. We show that $\omega$ is determined by $\sigma$,
and is a strictly weaker invariant.


title:
Gauge freedom in observables and Landsbergs nonadiabatic geometric
  phase: pumping spectroscopy of interacting open quantum systems

abstract:
  We set up a general density-operator approach to geometric steady-state
pumping through slowly driven open quantum systems. This approach applies to
strongly interacting systems that are weakly coupled to multiple reservoirs at
high temperature, illustrated by an Anderson quantum dot, but shows potential
for generalization. Pumping gives rise to a nonadiabatic geometric phase that
can be described by a framework originally developed for classical dissipative
systems by Landsberg. This geometric phase is accumulated by the transported
observable (charge, spin, energy) and not by the quantum state. It thus differs
radically from the adiabatic Berry-Simon phase, even when generalizing it to
mixed states, following Sarandy and Lidar. Importantly, our geometric
formulation of pumping stays close to a direct physical intuition (i) by tying
gauge transformations to calibration of the meter registering the transported
observable and (ii) by deriving a geometric connection from a driving-frequency
expansion of the current. Our approach provides a systematic and efficient way
to compute the geometric pumping of various observables, including charge,
spin, energy and heat. Our geometric curvature formula reveals a general
experimental scheme for performing geometric transport spectroscopy that
enhances standard nonlinear spectroscopies based on measurements for static
parameters. We indicate measurement strategies for separating the useful
geometric pumping contribution to transport from nongeometric effects. Finally,
we highlight several advantages of our approach in an exhaustive comparison
with the Sinitsyn-Nemenmann full-counting statistics (FCS) approach to
geometric pumping of an observable`s first moment. We explain how in the FCS
approach an "adiabatic" approximation leads to a manifestly nonadiabatic result
involving a finite retardation time of the response to parameter driving.


title: Quasi-local conserved charges in the Einstein-Maxwell theory

abstract:
  In this paper we consider the Einstein-Maxwell theory and define a combined
transformation composed of diffeomorphism and $U(1)$ gauge transformation. For
generality, we assume that the generator $\chi$ of such transformation is
field-dependent. We define the extended off-shell ADT current and then
off-shell ADT charge such that they are conserved off-shell for the
asymptotically field-dependent symmetry generator $\chi$. Then, we define the
conserved charge corresponding to the asymptotically field-dependent symmetry
generator $\chi$. We apply the presented method to find the conserved charges
of the asymptotically AdS$_{3}$ spacetimes in the context of the
Einstein-Maxwell theory in three dimensions. Although the usual proposal for
the quasi local charges provides divergent global charges for the
Einstein-Maxwell theory with negative cosmological constant in three
dimensions, here we avoid this problem by introducing proposed combined
transformation $\chi$.


title:
Construction and Assembly of the Wire Planes for the MicroBooNE Time
  Projection Chamber

abstract:
  In this paper we describe how the readout planes for the MicroBooNE Time
Projection Chamber were constructed, assembled and installed. We present the
individual wire preparation using semi-automatic winding machines and the
assembly of wire carrier boards. The details of the wire installation on the
detector frame and the tensioning of the wires are given. A strict quality
assurance plan ensured the integrity of the readout planes. The different tests
performed at all stages of construction and installation provided crucial
information to achieve the successful realisation of the MicroBooNE wire
planes.


title:
Statistical state dynamics based theory for the formation and
  equilibration of Saturn's north polar jet

abstract:
  Coherent jets with most of the kinetic energy of the flow are common in
atmospheric turbulence. In the gaseous planets these jets are maintained by
incoherent turbulence excited by small-scale convection. Large-scale coherent
waves are sometimes observed to coexist with the jets; a prominent example is
Saturn's hexagonal North polar jet (NPJ). The mechanism responsible for forming
and maintaining such a turbulent state remains elusive. The coherent
planetary-scale component of the turbulence arises and is maintained by
interaction with the incoherent small-scale turbulence component. Theoretical
understanding of the dynamics of the jet/wave/turbulence coexistence regime is
gained by employing a statistical state dynamics (SSD) model. Here, a
second-order closure implementation of a two-layer beta-plane SSD is used to
develop a theory that accounts for the structure and dynamics of the NPJ.
Asymptotic analysis of the SSD equilibrium in the weak jet damping limit
predicts a universal jet structure in agreement with NPJ observations. This
asymptotic theory also predicts the wavenumber (six) of the prominent jet
perturbation. Analysis with this model of the jet/wave/turbulence regime
dynamics reveals that jet formation is controlled by the effective value of
$\beta$; the required value of this parameter for correspondence with
observation is obtained. As this is a robust prediction it is taken as an
indirect observation of a deep poleward sloping stable layer beneath the NPJ.
The slope required is obtained from observations of NPJ structure as is the
small-scale turbulence excitation required to maintain the jet. The observed
jet structure is then predicted by the theory as is the wave-six disturbance.
This wave, which is identified with the least stable mode of the equilibrated
jet, is shown to be primarily responsible for equilibrating the jet with the
observed structure and amplitude.


title: Coincidences among skew dual stable Grothendieck polynomials

abstract:
  The question of when two skew Young diagrams produce the same skew Schur
function has been well-studied. We investigate the same question in the case of
stable Grothendieck polynomials, which are the K-theoretic analogues of the
Schur functions. We prove a necessary condition for two skew shapes to give
rise to the same dual stable Grothendieck polynomial. We also provide a
necessary and sufficient condition in the case where the two skew shapes are
ribbons.


title: Optimal stretching for lattice points and eigenvalues

abstract:
  We aim to maximize the number of first-quadrant lattice points in a convex
domain with respect to reciprocal stretching in the coordinate directions. The
optimal domain is shown to be asymptotically balanced, meaning that the stretch
factor approaches 1 as the "radius" approaches infinity. In particular, the
result implies that among all p-ellipses (or Lam\'e curves), the p-circle
encloses the most first-quadrant lattice points as the radius approaches
infinity.
  The case p=2 corresponds to minimization of high eigenvalues of the Dirichlet
Laplacian on rectangles, and so our work generalizes a result of Antunes and
Freitas. Similarly, we generalize a Neumann eigenvalue maximization result of
van den Berg, Bucur and Gittins.
  The case p=1 remains open: which right triangles in the first quadrant with
two sides along the axes will enclose the most lattice points, as the area
tends to infinity?


title: Electronic Decoherence of Two-Level Systems in a Josephson Junction

abstract:
  The sensitivity of superconducting qubits allows for spectroscopy and
coherence measurements on individual two-level systems present in the
disordered tunnel barrier of an $\mathrm{Al/AlO_x/Al}$ Josephson junction. We
report experimental evidence for the decoherence of two-level systems by
Bogoliubov quasiparticles leaking into the insulating $\mathrm{AlO_x}$ barrier.
We control the density of quasiparticles in the junction electrodes either by
the sample temperature or by injecting them using an on-chip dc-SQUID driven to
its resistive state. The decoherence rates were measured by observing the
two-level system's quantum state evolving under application of resonant
microwave pulses and were found to increase linearly with quasiparticle
density, in agreement with theory. This interaction with electronic states
provides a noise and decoherence mechanism that is relevant for various
microfabricated devices such as qubits, single-electron transistors, and
field-effect transistors. The presented experiments also offer a possibility to
determine the location of the probed two-level systems across the tunnel
barrier, providing clues about the fabrication step in which they emerge.


title: Comment on "Dislocation Structure and Mobility in hcp $^4$He"

abstract:
  In their Letter, Borda, Cai, and de Koning report the results of ab initio
simulations of dislocations responsible for the giant plasticity. The authors
claim key insights into the recent interpretations of (i) the giant plasticity
and (ii) the mass flow junction experiments. The purpose of this Comment is
clarifying the role of dislocations in the mass flow in conjunction with
explaining that the part (ii) of the claim is misleading.


title:
Reduction in energy dissipation rate with increased effective applied
  field

abstract:
  Dynamics of the response of type-II superconductors to a time-varying
magnetic field can exhibit a rate-independent or rate-dependent hysteresis. An
energy dissipation rate in a superconductor placed in a time-varying magnetic
field depends on its wave form and type of hysteresis, which depends on
temperature. The same wave form may reduce the energy dissipation rate in the
case of true hysteresis, while it may increase the energy dissipation rate in
the case of dynamic hysteresis compared with an energy dissipation rate in a
pure sinusoidal field. We present experimental data which confirm the energy
dissipation rate calculated using the critical state theory for the case of
rate-independent hysteresis and limiting behavior in a normal state for the
case of rate-dependent hysteresis.