title:
Robust Reactive Power Optimization and Voltage Control Method for Active
  Distribution Networks via Dual Time-scale Coordination

abstract:
  In distribution networks, there are slow controlling devices and fast
controlling devices for Volt-VAR regulation. These slow controlling devices,
such as capacitors or voltage regulators, cannot be operated frequently and
should be scheduled tens of minutes ahead (Hereafter named as slow control).
Since of the uncertainties in predicting the load and distributed generation,
the voltage violations cannot be eliminated by fast controlling devices with
improper schedule of the slow controlling devices. In this paper we propose
dual time-scale coordination for the Volt-VAR control scheme, corresponding to
slow and fast control. In the case of slow control, a robust voltage and
reactive power optimization model is developed. This guarantees that subsequent
fast controls can maintain the system's voltage security if the uncertain
parameters vary within predefined limits. This nonconvex optimization problem
is relaxed to a mix integer second order conic problem, and the dual form of
its sub-problem is also derived. Then a column-and-constraint generation
algorithm was used to solve the robust convexified model. A conventional
deterministic optimization model can be used to determine the fast control
mechanism. Numerical tests were conducted on a real distribution feeder in
China, a balanced IEEE 69-bus and unbalanced 123-bus benchmark distribution
networks. The simulation results show that solving the deterministic model is
not always feasible and voltage violation may occur. The robust model was shown
to be effective with respect to all possible scenarios in the uncertainty set,
with little compromise in terms of network losses.


title:
Mathematical model for pest-insect control using mating disruption and
  trapping

abstract:
  Controlling pest insects is a challenge of main importance to preserve crop
production. In the context of Integrated Pest Management (IPM) programs, we
develop a generic model to study the impact of mating disruption control using
an artificial female pheromone to confuse males and adversely affect their
mating opportunities. Consequently the reproduction rate is diminished leading
to a decline in the population size. For more efficient control, trapping is
used to capture the males attracted to the artificial pheromone. The model,
derived from biological and ecological assumptions, is governed by a system of
ODEs. A theoretical analysis of the model without control is first carried out
to establish the properties of the endemic equilibrium. Then, control is added
and the theoretical analysis of the model enables to identify threshold values
of pheromone which are practically interesting for field applications. In
particular, we show that there is a threshold above which the global asymptotic
stability of the trivial equilibrium is ensured, i.e. the population goes to
extinction. Finally we illustrate the theoretical results via numerical
experiments.


title: The Modular Gromov-Hausdorff Propinquity

abstract:
  We introduce a metric on Hilbert modules equipped with a generalized form of
a differential structure, thus extending Gromov-Hausdorff convergence theory to
vector bundles and quantum vector bundles --- not convergence as total space
but indeed as quantum vector bundle. Our metric is new even in the classical
picture, and creates a framework for the study of the moduli spaces of modules
over C*-algebras from a metric perspective. We apply our construction, in
particular, to the continuity of Heisenberg modules over quantum $2$-tori.


title:
Loss-resilient photonic entanglement swapping using optical hybrid
  states

abstract:
  We propose a scheme of loss-resilient entanglement swapping between two
distant parties via an imperfect optical channel. In this scheme, two copies of
hybrid entangled states are prepared and the continuous-variable parts
propagate through lossy media. In order to perform successful entanglement
swapping, several different measurement schemes are considered for the
continuousvariable parts such as single-photon detection for ideal cases and a
homodyne detection for practical cases. We find that the entanglement swapping
using hybrid states with small amplitudes offers larger entanglement than the
discrete-variable entanglement swapping in the presence of large losses.
Remarkably, this hybrid scheme still offers excellent robustness of
entanglement to the detection inefficiency. Thus, the proposed scheme could be
used for the practical quantum key distribution in hybrid optical states under
photon losses.


title: Approximating the Chromatic Polynomial

abstract:
  Chromatic polynomials are important objects in graph theory and statistical
physics, but as a result of computational difficulties, their study is limited
to graphs that are small, highly structured, or very sparse. We have devised
and implemented two algorithms that approximate the coefficients of the
chromatic polynomial $P(G,x)$, where $P(G,k)$ is the number of proper
$k$-colorings of a graph $G$ for $k\in\mathbb{N}$. Our algorithm is based on a
method of Knuth that estimates the order of a search tree. We compare our
results to the true chromatic polynomial in several known cases, and compare
our error with previous approximation algorithms.


title:
Non-invasive stabilization of periodic orbits in $O_4$-symmetrically
  coupled Van der Pol oscillators

abstract:
  Pyragas time delayed feedback control has proven itself as an effective tool
to non-invasively stabilize periodic solutions. In a number of publications,
this method was adapted to equivariant settings and applied to stabilize
branches of small periodic solutions in systems of symmetrically coupled Landau
oscillators near a Hopf bifurcation point. The form of the control ensures the
non-invasiveness property, hence reducing the problem to finding a set of the
gain matrices, which would guarantee the stabilization. In this paper, we apply
this method to a system of Van der Pol oscillators coupled in a cube-like
configuration leading to $O_4$-equivariance. We discuss group theoretic
restrictions which help to shape our choice of control. Furthermore, we
explicitly describe the domains in the parameter space for which the periodic
solutions are stable.


title:
Opaque Response Generation Enabling Automatic Creation of Virtual
  Services for Service Virtualisation

abstract:
  Service virtualisation is a method to create virtual service models that can
mimic interaction behaviors between a system under test and the target system.
With service virtualisation, the development team can get access to the
production-like conditions whenever and however many times they need, enabling
frequent and comprehensive testing. Previous techniques for service
virtualisation have relied on explicitly modelling the target services by a
service expert and require detailed knowledge of message protocol and
structure. However, neither of these are necessarily available.
  In this thesis, we introduce our novel opaque response generation approach.
This approach enables services to be virtualised automatically without any
expert knowledge or documentation of system protocol and interaction
behaviours. Given a collection of interactions exchanged between a system under
test and a target real service, our approach can 1) organise the same type of
interactions into the same cluster and derive a cluster prototype for each
cluster; 2) search a given incoming request for its the most similar request in
the interaction library; 3) learn knowledge from the incoming request and the
recorded interaction; and 4) generate a response. A framework and
proof-of-concept implementation of our opaque response generation approach is
described. Experimental results show our opaque response generation approach is
able to automatically generate accurate responses in real time with an accuracy
rate over 99% on average.


title: Maxi observations of long X-ray bursts

abstract:
  We report nine long X-ray bursts from neutron stars, detected with Monitor of
All-sky X-ray Image (MAXI). Some of these bursts lasted for hours, and hence
are qualified as superbursts, which are prolonged thermonuclear flashes on
neutron stars and are relatively rare events. MAXI observes roughly 85% of the
whole sky every 92 minutes in the 2-20 keV energy band, and has detected nine
bursts with a long e-folding decay time, ranging from 0.27 to 5.2 hours, since
its launch in 2009 August until 2015 August. The majority of the nine events
were found to originate from transient X-ray sources. The persistent
luminosities of the sources, when these prolonged bursts were observed, were
lower than 1% of the Eddington luminosity for five of them and lower than 20%
for the rest. This trend is contrastive to the 18 superbursts observed before
MAXI, all but two of which originated from bright persistent sources. The
distribution of the total emitted energy, i.e., the product of e-folding time
and luminosity, of these bursts clusters around $10^{41}$-$10^{42}$ erg,
whereas either of the e-folding time and luminosity ranges for an order of
magnitude. Among the nine events, two were from 4U 1850-086 during the phases
of relatively low persistent-flux, whereas it usually exhibits standard short
X-ray bursts during outbursts.


title: Entanglement entropy of the $Q \ge 4$ quantum Potts chain

abstract:
  The entanglement entropy, ${\cal S}$, is an indicator of quantum correlations
in the ground state of a many body quantum system. At a second-order quantum
phase-transition point in one dimension ${\cal S}$ generally has a logarithmic
singularity. Here we consider quantum spin chains with a first-order quantum
phase transition, the prototype being the $Q$-state quantum Potts chain for
$Q>4$ and calculate ${\cal S}$ across the transition point. According to
numerical, density matrix renormalization group results at the first-order
quantum phase transition point ${\cal S}$ shows a jump, which is expected to
vanish for $Q \to 4^+$. This jump is calculated in leading order as $\Delta
{\cal S}=\ln Q[1-4/Q-2/(Q \ln Q)+{\cal O}(1/Q^2)]$.


title: The metrology system of the VLTI instrument GRAVITY

abstract:
  The VLTI instrument GRAVITY combines the beams from four telescopes and
provides phase-referenced imaging as well as precision-astrometry of order 10
microarcseconds by observing two celestial objects in dual-field mode. Their
angular separation can be determined from their differential OPD (dOPD) when
the internal dOPDs in the interferometer are known. Here, we present the
general overview of the novel metrology system which performs these
measurements. The metrology consists of a three-beam laser system and a
homodyne detection scheme for three-beam interference using phase-shifting
interferometry in combination with lock-in amplifiers. Via this approach the
metrology system measures dOPDs on a nanometer-level.


title: New mechanism of acceleration of particles by stellar black holes

abstract:
  In this paper we study efficiency of particle acceleration in the
magnetospheres of stellar mass black holes. For this purpose we consider the
linearized set of the Euler equation, continuity equation and Poisson equation
respectively. After introducing the varying relativistic centrifugal force, we
show that the charge separation undergoes the parametric instability, leading
to generation of centrifugally excited Langmuir waves. It is shown that these
waves, via the Langmuir collapse damp by means of the Landau damping, as a
result energy transfers to particles accelerating them to energies of the order
of $10^{16}$eV.


title:
Emulating anyonic fractional statistical behavior in a superconducting
  quantum circuit

abstract:
  Anyons are exotic quasiparticles obeying fractional statistics,whose behavior
can be emulated in artificially designed spin systems.Here we present an
experimental emulation of creating anyonic excitations in a superconducting
circuit that consists of four qubits, achieved by dynamically generating the
ground and excited states of the toric code model, i.e., four-qubit
Greenberger-Horne-Zeilinger states. The anyonic braiding is implemented via
single-qubit rotations: a phase shift of \pi related to braiding, the hallmark
of Abelian 1/2 anyons, has been observed through a Ramsey-type interference
measurement.


title:
Mumford curves covering p-adic Shimura curves and their fundamental
  domains

abstract:
  We give an explicit description of fundamental domains associated to the
$p$-adic uniformisation of families of Shimura curves of discriminant $Dp$ and
level $N\geq 1$, for which the one-sided ideal class number $h(D,N)$ is $1$.
The obtained results generalise those in \cite[Ch. IX]{Gerritzen_vanderPut1980}
for Shimura curves of discriminant $2p$ and level $N=1$. The method we present
here enables us to find Mumford curves covering Shimura curves, together with a
free system of generators for the associated Schottky groups, $p$-adic good
fundamental domains and their stable reduction-graphs. This is based on a
detailed study of the modular arithmetic of an Eichler order of level $N$
inside the definite quaternion algebra of discriminant $D$, for which we
generalise classical results of Hurwitz \cite{Hurwitz1896}. As an application,
we prove general formulas for the reduction-graphs with lengths at $p$ of the
considered families of Shimura curves.


title:
Narrow-line-width UV bursts in the transition region above Sunspots
  observed by IRIS

abstract:
  Various small-scale structures abound in the solar atmosphere above active
regions, playing an important role in the dynamics and evolution therein. We
report on a new class of small-scale transition region structures in active
regions, characterized by strong emissions but extremely narrow Si IV line
profiles as found in observations taken with the Interface Region Imaging
Spectrograph (IRIS). Tentatively named as Narrow-line-width UV bursts (NUBs),
these structures are located above sunspots and comprise of one or multiple
compact bright cores at sub-arcsecond scales. We found six NUBs in two datasets
(a raster and a sit-and-stare dataset). Among these, four events are
short-living with a duration of $\sim$10 mins while two last for more than 36
mins. All NUBs have Doppler shifts of 15--18 km/s, while the NUB found in
sit-and-stare data possesses an additional component at $\sim$50 km/s found
only in the C II and Mg II lines. Given that these events are found to play a
role in the local dynamics, it is important to further investigate the physical
mechanisms that generate these phenomena and their role in the mass transport
in sunspots.


title:
Helioseismic holography of simulated sunspots: magnetic and thermal
  contributions to travel times

abstract:
  Wave propagation through sunspots involves conversion between waves of
acoustic and magnetic character. In addition, the thermal structure of sunspots
is very different than that of the quiet Sun. As a consequence, the
interpretation of local helioseismic measurements of sunspots has long been a
challenge. With the aim of understanding these measurements, we carry out
numerical simulations of wave propagation through sunspots. Helioseismic
holography measurements made from the resulting simulated wavefields show
qualitative agreement with observations of real sunspots. We use additional
numerical experiments to determine, separately, the influence of the thermal
structure of the sunspot and the direct effect of the sunspot magnetic field.
We use the ray approximation to show that the travel-time shifts in the thermal
(non-magnetic) sunspot model are primarily produced by changes in the wave path
due to the Wilson depression rather than variations in the wave speed. This
shows that inversions for the subsurface structure of sunspots must account for
local changes in the density. In some ranges of horizontal phase speed and
frequency there is agreement (within the noise level in the simulations)
between the travel times measured in the full magnetic sunspot model and the
thermal model. If this conclusion proves to be robust for a wide range of
models, it would suggest a path towards inversions for sunspot structure.


title:
Gamma ray vortices from nonlinear inverse Compton scattering of
  circularly polarized light

abstract:
  Inverse Compton scattering (ICS) is an elemental radiation process that
produces high-energy photons both in nature and in the laboratory. Non-linear
ICS is a process in which multiple photons are converted to a single
high-energy photon. Here, we theoretically show that the photon produced by
non-linear ICS of circularly polarized photons is a vortex, which means that it
possesses a helical wave front and carries orbital angular momentum. Our work
explains a recent experimental result regarding non-linear Compton scattering
that clearly shows an annular intensity distribution as a remarkable feature of
a vortex beam. Our work implies that gamma ray vortices should be produced in
various situations in astrophysics in which high-energy electrons and intense
circularly polarized light fields coexist. They should play a critical role in
stellar nucleosynthesis. Non-linear ICS is the most promising radiation process
for realizing a gamma ray vortex source based on currently available laser and
accelerator technologies, which would be an indispensable tool for exploring
gamma ray vortex science.


title: Theory of pulsar magnetosphere and wind

abstract:
  Neutron stars are fascinating astrophysical objects immersed in strong
gravitational and electromagnetic fields, at the edge of our current theories.
These stars manifest themselves mostly as pulsars, emitting a timely very
stable and regular electromagnetic signal. Even though discovered almost fifty
years ago, they still remain mysterious compact stellar objects. In this
review, we summarize the most fundamental theoretical aspects of neutron star
magnetospheres and winds. The main competing models susceptible to explain
their radiative properties like multi-wavelength pulse shapes and spectra and
the underlying physical processes such as pair creation and radiation
mechanisms are scrutinized. A global but still rather qualitative picture
emerges slowly thanks to recent advances in numerical simulations on the
largest scales. However considerations about pulsar magnetospheres remain
speculative. For instance the exact composition of the magnetospheric plasma is
not yet known. Is it solely filled with a mixture of $e^\pm$~leptons, or does
it contain a non negligible fraction of protons and/or ions? Actually, is it
almost entirely filled or mostly empty except for some small anecdotal plasma
filled regions? Answers to these questions will strongly direct the description
of the magnetosphere to seemingly contradictory results leading sometimes to
inconsistencies. Nevertheless, account are given to the latest developments in
the theory of pulsar magnetospheres and winds, the existence of a possible
electrosphere and physical insight obtained from related observational
signatures of multi-wavelength pulsed emission.


title:
Optimisation of the lowest Robin eigenvalue in the exterior of a compact
  set

abstract:
  We consider the problem of geometric optimisation of the lowest eigenvalue of
the Laplacian in the exterior of a compact planar set, subject to attractive
Robin boundary conditions. Under either a constraint of fixed perimeter or
area, we show that the maximiser within the class of exteriors of convex sets
is always the exterior of a disk. We also argue why the results fail without
the convexity constraint and in higher dimensions.


title: Metal-loaded organic scintillators for neutrino physics

abstract:
  Organic liquid scintillators are used in many neutrino physics experiments of
the past and present. In particular for low energy neutrinos when realtime and
energy information are required, liquid scintillators have several advantages
compared to other technologies. In many cases the organic liquid needs to be
loaded with metal to enhance the neutrino signal over background events.
Several metal loaded scintillators of the past suffered from chemical and
optical instabilities, limiting the performance of these neutrino detectors.
Different ways of metal loading are described in the article with a focus on
recent techniques providing metal loaded scintillators that can be used under
stable conditions for many years even in ton scale experiments. Applications of
metal loaded scintillators in neutrino experiments are reviewed and the
performance as well as the prospects of different scintillator types are
compared.


title:
Von-Neumann finiteness and reversibility in some classes of
  non-associative algebras

abstract:
  We investigate criteria for von-Neumann finiteness and reversibility in some
classes of non-associative algebras. We show that all finite-dimensional
alternative algebras, as well as all algebras obtained from the real numbers
via the standard Cayley-Dickson doubling process, are von-Neumann finite.
Precise criteria for von-Neumann finiteness and reversibility of involutive
algebras are given, in terms of isomorphism types of their 3-dimensional
subalgebras.


title:
Exactly Solved Models and Beyond: a special issue in honour of R J
  Baxter's 75th birthday

abstract:
  This is an introduction to Exactly Solved Models and Beyond, a special issue
collection of articles published in J. Phys. A in honour of R J Baxter's 75th
birthday.

categories: cond-mat.stat-mech hep-th math-ph math.MP


title:
On the logarithmic divergent part of entanglement entropy, smooth versus
  singular regions

abstract:
  The entanglement entropy for smooth regions $\cal A$ has a logarithmic
divergent contribution with a shape dependent coefficient and that for regions
with conical singularities an additional $\log ^2$ term. Comparing the
coefficient of this extra term, obtained by direct holographic calculation for
an infinite cone, with the corresponding limiting case for the shape dependent
coefficient for a regularised cone, a mismatch by a factor two has been
observed in the literature. We discuss several aspects of this issue. In
particular a regularisation of $\cal A$, intrinsically delivered by the
holographic picture, is proposed and applied to an example of a compact region
with two conical singularities. Finally, the mismatch is removed in all studied
regularisations of $\cal A$, if equal scale ratios are chosen for the limiting
procedure.


title: Evolutionary algorithm based configuration interaction approach

abstract:
  A stochastic configuration interaction method based on evolutionary algorithm
is designed as an affordable approximation to full configuration interaction
(FCI). The algorithm comprises of initiation, propagation and termination
steps, where the propagation step is performed with cloning, mutation and
cross-over, taking inspiration from genetic algorithm. We have tested its
accuracy in 1D Hubbard problem and a molecular system (symmetric bond breaking
of water molecule). We have tested two different fitness functions based on
energy of the determinants and the CI coefficients of determinants. We find
that the absolute value of CI coefficients is a more suitable fitness function
when combined with a fixed selection scheme.


title:
Globally Variance-Constrained Sparse Representation and Its Application
  in Image Set Coding

abstract:
  Sparse representation leads to an efficient way to approximately recover a
signal by the linear composition of a few bases from a learnt dictionary, based
on which various successful applications have been achieved. However, in the
scenario of data compression, its efficiency and popularity are hindered. It is
because of the fact that encoding sparsely distributed coefficients may consume
more bits for representing the index of nonzero coefficients. Therefore,
introducing an accurate rate-constraint in sparse coding and dictionary
learning becomes meaningful, which has not been fully exploited in the context
of sparse representation. According to the Shannon entropy inequality, the
variance of a Gaussian distributed data bounds its entropy, indicating the
actual bitrate can be well estimated by its variance. Hence, a Globally
Variance-Constrained Sparse Representation (GVCSR) model is proposed in this
work, where a variance-constrained rate term is introduced to the optimization
process. Specifically, we employ the Alternating Direction Method of
Multipliers (ADMM) to solve the non-convex optimization problem for sparse
coding and dictionary learning, both of them have shown the state-of-the-art
rate-distortion performance for image representation. Furthermore, we
investigate the potential of applying the GVCSR algorithm in the practical
image set compression, where the optimized dictionary is trained to efficiently
represent the images captured in similar scenarios by implicitly utilizing
inter-image correlations. Experimental results have demonstrated superior
rate-distortion performance against the state-of-the-art methods.


title: Atomic-scale sensor for charge- and atomic-lattice-dynamics on surfaces

abstract:
  We present here a powerful method providing simultaneous atomic spatial and
nanosecond temporal resolution for investigating dynamics and structure on the
atomic scale, in general. We reveal the dynamic reorganization of surface
(ad)atoms induced by radio frequency alternating charging and decharging of a
metal. Our method utilizes taylor-made nano-fabricated two-dimensional islands
of physisorbed argon atoms, acting as motion sensors, probed by a radio
frequency low-temperature scanning tunneling microscope.


title:
RMPCDMD: Simulations of colloids with coarse-grained hydrodynamics,
  chemical reactions and external fields

abstract:
  The RMPCDMD software package performs hybrid Molecular Dynamics simulations,
coupling Multiparticle Collision Dynamics to model the solvent and Molecular
Dynamics to model suspended colloids, including hydrodynamics, thermal
fluctuations, and chemically active solvent particles and catalytic colloids.
The main usage of RMPCDMD is the simulation of chemically powered nanomotors,
but other setups are considered: colloids in the presence of a thermal
gradients or forced flows. RMPCDMD is developed in Fortran 2008 with OpenMP for
multithreaded operation and uses the HDF5-based H5MD file format for storing
data. RMPCDMD comes with documentation and a tutorial for the simulation of
chemically powered nanomotors.


title: Quantum Soliton Evaporation

abstract:
  We have very little experience of the quantum dynamics of the ubiquitous
nonlinear waves. Observed phenomena in high energy physics are perturbations to
linear waves, and classical nonlinear waves, like solitons, are barely affected
by quantum effects. We know that solitons, immutable in classical physics,
exhibit collapse and revivals according to quantum mechanics. However this
effect is very weak and has never been observed experimentally. By predicting
black hole evaporation Hawking first introduced a distinctly quantum effect in
nonlinear gravitational physics.Here we show the existence of a general and
universal quantum process whereby a soliton emits quantum radiation with a
specific frequency content, and a temperature given by the number of quanta,
the soliton Schwarzschild radius, and the amount of nonlinearity, in a precise
and surprisingly simple way. This result may ultimately lead to the first
experimental evidence of genuine quantum black hole evaporation. In addition,
our results show that black hole radiation occurs in a fully quantised theory,
at variance with the common approach based on quantum field theory in a curved
background; this may provide insights into quantum gravity theories. Our
findings also have relevance to the entire field of nonlinear waves, including
cold atomic gases and extreme phenomena such as shocks and rogue-waves.
Finally, the predicted effect may potentially be exploited for novel tunable
quantum light sources.

categories: physics.optics cond-mat.quant-gas nlin.PS physics.atom-ph quant-ph


title: Quicksort Is Optimal For Many Equal Keys

abstract:
  I prove that the average number of comparisons for median-of-$k$ Quicksort
(with fat-pivot a.k.a. three-way partitioning) is asymptotically only a
constant $\alpha_k$ times worse than the lower bound for sorting random
multisets with $\Omega(n^\varepsilon)$ duplicates of each value (for any
$\varepsilon>0$). The constant is $\alpha_k = \ln(2) /
\bigl(H_{k+1}-H_{(k+1)/2} \bigr)$, which converges to 1 as $k\to\infty$, so
Quicksort is asymptotically optimal for inputs with many duplicates. This
resolves a conjecture by Sedgewick and Bentley (1999, 2002) and constitutes the
first progress on the analysis of Quicksort with equal elements since
Sedgewick's 1977 article.


title: Gr\"uneisen parameter studies on heavy fermion quantum criticality

abstract:
  The Gr\"uneisen parameter, experimentally determined from the ratio of
thermal expansion to specific heat, quantifies the pressure dependence of
characteristic energy scales of matter. It is highly enhanced for Kondo lattice
systems, whose properties strongly dependent on the pressure sensitive
antiferromagnetic exchange interaction between f- and conduction electrons. In
this review, we focus on the divergence of the Gr\"uneisen parameter and its
magnetic analogue, the adiabatic magnetocaloric effect, for heavy-fermion
metals near quantum critical points. We compare experimental results with
current theoretical models, including the effect of strong geometrical
frustration. We also discuss the possibility to use materials with divergent
magnetic Gr\"uneisen parameter for adiabatic demagnetization cooling to very
low temperatures.


title:
A two-fold quantum delayed-choice experiment in a superconducting
  circuit

abstract:
  We propose and experimentally demonstrate a two-fold quantum delayed-choice
experiment where wave or particle nature of a superconducting interfering
device can be post-selected twice after the interferometer. The wave-particle
complementarity is controlled by a quantum which-path detector (WPD) in a
superposition of its on and off states implemented through a superconducting
cavity. The WPD projected to its on state records which-path information, which
manifests the particle nature and destroys the interference associated with
wave nature of the system. In our experiment, we can recover the interference
signal through a quantum eraser even if the WPD has selected out the particle
nature in the first round of delayed-choice detection, showing that a quantum
WPD adds further unprecedented controllability to test of wave-particle
complementarity through the peculiar quantum delayed-choice measurements.


title:
A high visibility Hong-Ou-Mandel interference via a time-resolved
  coincidence measurement

abstract:
  We report on the observation of a high visibility Hong-Ou-Mandel interference
of two heralded photons emitted from a spontaneous parametric down
conversion~(SPDC) pumped by continuous-wave~(cw) light. A non-degenerate photon
pair at 1541~nm and 1580~nm is generated by cw-pumped SPDC through a
periodically poled lithium niobate waveguide. The heralded single photon at
1541~nm is prepared by the detection of the photon at 1580~nm. We performed the
experiment of the Hong-Ou-Mandel interference between heralded single photons
in separated time bins and observed a high visibility interference. All
detectors we used are superconducting nanowire single-photon detectors and an
overall temporal resolution of the photon detection is estimated as 85 ps,
which is sufficiently shorter than the coherence time of the heralded photons.


title:
Tweedie distributions for fitting semicontinuous health care utilization
  cost data

abstract:
  We explore a statistical distribution that can simultaneously model the
probability of zero outcome for non-users of health care utilization and
continuous costs for users. We compare this distribution to other com- monly
used models on example data and show that it fits cost data well and has some
appealing properties that provide flexible use.


title:
Leptogenesis after Chaotic Sneutrino Inflation and the Supersymmetry
  Breaking Scale

abstract:
  We discuss resonant leptogenesis arising from the decays of two
nearly-degenerate right-handed neutrinos, identified as the inflaton and
stabiliser superfields in a model of chaotic sneutrino inflation. We compare an
analytical estimate of the baryon asymmetry $ \eta_B $ in the Boltzmann
approximation to a numerical solution of the full density matrix equations, and
find that the analytical result fails to capture the correct physics in certain
regions of parameter space. The observed baryon asymmetry can be realised for a
breaking of the mass degeneracy as small as $ \mathcal{O}(10^{-8}) $. The
origin of such a small mass splitting is explained by considering supersymmetry
(SUSY) breaking in supergravity, which requires a constant in the
superpotential of the order of the gravitino mass $ m_{3/2} $ to cancel the
cosmological constant. This yields additional terms in the (s)neutrino mass
matrices, lifting the degeneracy and linking $ \eta_B $ to the SUSY breaking
scale. We find that achieving the correct baryon asymmetry requires a gravitino
mass $ m_{3/2} \geq \mathcal{O}(100) $ TeV.


title: Correlators with $s\ell_2$ Yangian symmetry

abstract:
  Correlators based on $s\ell_2$ Yangian symmetry and its quantum deformation
are studied. Symmetric integral operators can be defined with such correlators
as kernels. Yang-Baxter operators can be represented in this way. Particular
Yangian symmetric correlators are related to the kernels of QCD parton
evolution. The solution of the eigenvalue problem of Yangian symmetric
operators is described.


title:
When an Equivalence Relation with All Borel Classes will be Borel
  Somewhere?

abstract:
  In $\mathsf{ZFC}$, if there is a measurable cardinal with infinitely many
Woodin cardinals below it, then for every equivalence relation $E \in
L(\mathbb{R})$ on $\mathbb{R}$ with all $\mathbf{\Delta}_1^1$ classes and every
$\sigma$-ideal $I$ on $\mathbb{R}$ so that the associated forcing
$\mathbb{P}_I$ of $I^+$ $\mathbf{\Delta}_1^1$ subsets is proper, there exists
some $I^+$ $\mathbf{\Delta}_1^1$ set $C$ so that $E \upharpoonright C$ is a
$\mathbf{\Delta}_1^1$ equivalence relation. In $\mathsf{ZF} + \mathsf{DC} +
\mathsf{AD}_\mathbb{R} + V = L(\mathscr{P}(\mathbb{R}))$, for every equivalence
relation $E$ on $\mathbb{R}$ with all $\mathbf{\Delta}_1^1$ classes and every
$\sigma$-ideal $I$ on $\mathbb{R}$ so that the associated forcing
$\mathbb{P}_I$ is proper, there is some $I^+$ $\mathbf{\Delta}_1^1$ set $C$ so
that $E \upharpoonright C$ is a $\mathbf{\Delta}_1^1$ equivalence relation.


title:
Geometry-aware Similarity Learning on SPD Manifolds for Visual
  Recognition

abstract:
  Symmetric Positive Definite (SPD) matrices have been widely used for data
representation in many visual recognition tasks. The success mainly attributes
to learning discriminative SPD matrices with encoding the Riemannian geometry
of the underlying SPD manifold. In this paper, we propose a geometry-aware SPD
similarity learning (SPDSL) framework to learn discriminative SPD features by
directly pursuing manifold-manifold transformation matrix of column full-rank.
Specifically, by exploiting the Riemannian geometry of the manifold of
fixed-rank Positive Semidefinite (PSD) matrices, we present a new solution to
reduce optimizing over the space of column full-rank transformation matrices to
optimizing on the PSD manifold which has a well-established Riemannian
structure. Under this solution, we exploit a new supervised SPD similarity
learning technique to learn the transformation by regressing the similarities
of selected SPD data pairs to their ground-truth similarities on the target SPD
manifold. To optimize the proposed objective function, we further derive an
algorithm on the PSD manifold. Evaluations on three visual classification tasks
show the advantages of the proposed approach over the existing SPD-based
discriminant learning methods.


title: Study of Instability of Liquid Jets Under Gravity

abstract:
  Breakup of water jets under gravity is a common-place phenomenon. The role of
surface tension in the instability of water jets was recognized by Rayleigh and
the theory propounded goes by the name of Plateau-Rayleigh theory. The necks
and bulges down along the jet-length that are created by perturbation waves of
wavelengths larger than a certain value keep growing with time and ultimately
cause the jet to breakup into drops. The effect of perturbation waves have been
investigated experimentally and found to confirm the essentials of the theory.
However, there is no unanimity about the origin of these perturbation waves.
Recently, the idea of recoil capillary waves as an important source of the
perturbation waves has been emphasized. The recoil of the end point of the
remaining continuous jet at its breakup point is considered to travel upward as
a recoil capillary wave which gets reflected at the mouth of the nozzle from
which the jet originates. The reflected capillary wave travels along the jet
downward with its Doppler shifted wavelength as a perturbation wave. We set up
an experiment to directly verify the existence and effect of the recoil
capillary waves and present some preliminary results of our experiment.


title: On Doubling and Volume: Chains

abstract:
  The well--known Freiman--Ruzsa Theorem provides a structural description of a
set $A$ of integers with $|2A|\le c|A|$ as a subset of a $d$--dimensional
arithmetic progression $P$ with $|P|\le c'|A|$, where $d$ and $c'$ depend only
on $c$. The estimation of the constants $d$ and $c'$ involved in the statement
has been the object of intense research. Freiman conjectured in 2008 a formula
for the largest volume of such a set. In this paper we prove the conjecture for
a general class of sets called chains.


title:
Cohesion and Coalition Formation in the European Parliament: Roll-Call
  Votes and Twitter Activities

abstract:
  We study the cohesion within and the coalitions between political groups in
the Eighth European Parliament (2014--2019) by analyzing two entirely different
aspects of the behavior of the Members of the European Parliament (MEPs) in the
policy-making processes. On one hand, we analyze their co-voting patterns and,
on the other, their retweeting behavior. We make use of two diverse datasets in
the analysis. The first one is the roll-call vote dataset, where cohesion is
regarded as the tendency to co-vote within a group, and a coalition is formed
when the members of several groups exhibit a high degree of co-voting agreement
on a subject. The second dataset comes from Twitter; it captures the retweeting
(i.e., endorsing) behavior of the MEPs and implies cohesion (retweets within
the same group) and coalitions (retweets between groups) from a completely
different perspective.
  We employ two different methodologies to analyze the cohesion and coalitions.
The first one is based on Krippendorff's Alpha reliability, used to measure the
agreement between raters in data-analysis scenarios, and the second one is
based on Exponential Random Graph Models, often used in social-network
analysis. We give general insights into the cohesion of political groups in the
European Parliament, explore whether coalitions are formed in the same way for
different policy areas, and examine to what degree the retweeting behavior of
MEPs corresponds to their co-voting patterns. A novel and interesting aspect of
our work is the relationship between the co-voting and retweeting patterns.


title: Linear inverse problems for Markov processes and their regularisation

abstract:
  We study the solutions of the inverse problem \[ g(z)=\int f(y) P_T(z,dy) \]
for a given $g$, where $(P_t(\cdot,\cdot))_{t \geq 0}$ is the transition
function of a given Markov process, $X$, and $T$ is a fixed deterministic time,
which is linked to the solutions of the ill-posed Cauchy problem \[ u_t + A
u=0, \qquad u(0,\cdot)=g, \] where $A$ is the generator of $X$. A necessary and
sufficient condition ensuring square integrable solutions is given. Moreover, a
family of regularisations for the above problems is suggested. We show in
particular that these inverse problems have a solution when $X$ is replaced by
$\xi X + (1-\xi)J$, where $\xi$ is a Bernoulli random variable, whose
probability of success can be chosen arbitrarily close to $1$, and $J$ is a
suitably constructed jump process.


title: Higgs Vacuum Stability and Modified Chaotic Inflation

abstract:
  The issue of electroweak vacuum stability is studied in presence of a scalar
field which participates in modifying the minimal chaotic inflation model. It
is shown that the threshold effect on the Higgs quartic coupling originating
from the Higgs-inflaton sector interaction can essentially make the electroweak
vacuum stable upto the Planck scale. On the other hand we observe that the new
physics parameters in this combined framework are enough to provide deviation
from the minimal chaotic inflation predictions so as to keep it consistent with
recent observation by Planck 2015.


title: Soft factors for double parton scattering at NNLO

abstract:
  We show at NNLO that the soft factors for double parton scattering (DPS) for
both integrated and unintegrated kinematics, can be presented entirely in the
terms of the soft factor for single Drell-Yan process, i.e. the transverse
momentum dependent (TMD) soft factor. Using the linearity of the logarithm of
TMD soft factor in rapidity divergences, we decompose the DPS soft factor
matrices into a product of matrices with rapidity divergences in given sectors,
and thus, define individual double parton distributions at NNLO. The rapidity
anomalous dimension matrices for double parton distributions are presented in
the terms of TMD rapidity anomalous dimension. The analysis is done using the
generating function approach to web diagrams. Significant part of the result is
obtained from the symmetry properties of web diagrams without referring to
explicit expressions or a particular rapidity regularization scheme.
Additionally, we present NNLO expression for the web diagram generating
function for Wilson lines with two light-like directions.


title: Super-spectral curve of irregular conformal blocks

abstract:
  We use super-spectral curve to investigate irregular conformal states of
integer and half-odd integer rank. The spectral curve is the loop equation of
supersymmetrized irregular matrix model. The case of integer rank corresponds
to the colliding limit of supersymmetric vertex operators of NS sector and
half-odd integer to the Ramond sectors. The spectral curve is simply integrable
at Nekrasov-Shatashvili limit and the partition function (inner product of
irregular conformal state) is obtained from the superconformal structure
manifest in the spectral curve. We present some explicit forms of the partition
function of integer (NS sector) and of half-odd ranks (Ramond sector).


title:
Chiral vortical effect from the compactified D4-branes with smeared
  D0-brane charge

abstract:
  By using the boundary derivative expansion formalism of fluid/gravity
correspondence, we study the chiral vortical effect from the compactified
D4-branes with smeared D0-brane charge. This background corresponds to a
strongly coupled, nonconformal relativistic fluid with a conserved vector
current. The presence of the chiral vortical effect is induced by the addition
of a Chern-Simons term in the bulk action. Except that the non-dissipative
anomalous viscous coefficient and the sound speed rely only on the chemical
potential, most of the other thermal and hydrodynamical quantities of the first
order depend both on the temperature and the chemical potential. According to
our result, the way that the chiral vortical effect coefficient depends on the
chemical potential seems irrelevant with whether the relativistic fluid is
conformal or not. Stability analysis shows that this anomalous relativistic
fluid is stable and the doping of the smeared D0-brane charge will slow down
the sound speed.


title:
Squared eigenvalue condition numbers and eigenvector correlations from
  the single ring theorem

abstract:
  We extend the so-called "single ring theorem"[1], also known as the
Haagerup-Larsen theorem[2], by showing that in the limit when the size of the
matrix goes to infinity a particular correlator between left and right
eigenvectors of the relevant non-hermitian matrix $X$, being the spectral
density weighted by the squared eigenvalue condition number, is given by a
simple formula involving only the radial spectral cumulative distribution
function of $X$. We show that this object allows to calculate the conditional
expectation of the squared eigenvalue condition number. We give examples and we
provide cross-check of the analytic prediction by the large scale numerics.


title:
Networks of $\cdot/G/\infty$ Server Queues with Shot-Noise-Driven
  Arrival Intensities

abstract:
  We study infinite-server queues in which the arrival process is a Cox process
(or doubly stochastic Poisson process), of which the arrival rate is given by
shot noise. A shot-noise rate emerges as a natural model, if the arrival rate
tends to display sudden increases (or: shots) at random epochs, after which the
rate is inclined to revert to lower values. Exponential decay of the shot noise
is assumed, so that the queueing systems are amenable for analysis. In
particular, we perform transient analysis on the number of customers in the
queue jointly with the value of the driving shot-noise process. Additionally,
we derive heavy-traffic asymptotics for the number of customers in the system
by using a linear scaling of the shot intensity. First we focus on a one
dimensional setting in which there is a single infinite-server queue, which we
then extend to a network setting.


title:
Gravitational wave generation by interaction of high power lasers with
  matter. Part II: Ablation and Piston models

abstract:
  We analyze theoretical models of gravitational waves generation in the
interaction of high intensity laser with matter, namely ablation and piston
models. We analyse the generated gravitational waves in linear approximation of
gravitational theory. We derive the analytical formulas and estimates for the
metric perturbations and the radiated power of generated gravitational waves.
Furthermore we investigate the characteristics of polarization and the
behaviour of test particles in the presence of gravitational wave which will be
important for the detection.


title: New non-standard Lagrangians for the Li\'enard-type equations

abstract:
  Li\'enard-type equations are used for the description of various phenomena in
physics and other fields of science. Here we find a new family of the
Li\'enard-type equations which admits a non-standard autonomous Lagrangian. As
a by-product we obtain autonomous first integrals for each member of this
family of equations. We also show that some of the previously known conditions
for the existence of a non-standard Lagrangian for the Li\'enard-type equations
follow from the linearizability of the corresponding equation via nonlocal
transformations.


title: Anyon Chains with Pairing Terms

abstract:
  In this paper we introduce a one-dimensional model of $su(2)_k$ anyons in
which the number of anyons can fluctuate by means of a pairing term. The model
can be tuned to a point at which one can determine the exact zero-energy ground
states, in close analogy to the spin-1 AKLT model. We also determine the points
at which the model is integrable and determine the behavior of the model at
these integrable points.


title:
Non-reciprocal few-photon devices based on chiral waveguide-emitter
  couplings

abstract:
  We demonstrate the possibility of designing efficient, non reciprocal
few-photon devices by exploiting the chiral coupling between two waveguide
modes and a single quantum emitter. We show how this system can induce
non-reciprocal photon transport at the single-photon level and act as an
optical diode. Afterwards, we also show how the same system shows a
transistor-like behaviour for a two-photon input. The efficiency in both cases
is shown to be large for feasible experimental implementations. Our results
illustrate the potential of chiral waveguide-emitter couplings for applications
in quantum circuitry.


title:
Reinforcement Learning algorithms for regret minimization in structured
  Markov Decision Processes

abstract:
  A recent goal in the Reinforcement Learning (RL) framework is to choose a
sequence of actions or a policy to maximize the reward collected or minimize
the regret incurred in a finite time horizon. For several RL problems in
operation research and optimal control, the optimal policy of the underlying
Markov Decision Process (MDP) is characterized by a known structure. The
current state of the art algorithms do not utilize this known structure of the
optimal policy while minimizing regret. In this work, we develop new RL
algorithms that exploit the structure of the optimal policy to minimize regret.
Numerical experiments on MDPs with structured optimal policies show that our
algorithms have better performance, are easy to implement, have a smaller
run-time and require less number of random number generations.


title:
On the characterization of vector rogue waves in two-dimensional two
  coupled nonlinear Schr\"{o}dinger equations with distributed coefficients

abstract:
  We construct vector rogue wave solutions of the two-dimensional two coupled
nonlinear Schr\"{o}dinger equations with distributed coefficients, namely
diffraction, nonlinearity and gain parameters through similarity transformation
technique. We transform the two-dimensional two coupled variable coefficients
nonlinear Schr\"{o}dinger equations into Manakov equation with a constraint
that connects diffraction and gain parameters with nonlinearity parameter. We
investigate the characteristics of the constructed vector rogue wave solutions
with four different forms of diffraction parameters. We report some interesting
patterns that occur in the rogue wave structures. Further, we construct vector
dark rogue wave solutions of the two-dimensional two coupled nonlinear
Schr\"{o}dinger equations with distributed coefficients and report some novel
characteristics that we observe in the vector dark rogue wave solutions.


title:
Anisotropic Elliott-Yafet Theory and Application to KC$_8$ Potassium
  Intercalated Graphite

abstract:
  We report Electron Spin Resonance (ESR) measurements on stage-I potassium
intercalated graphite (KC$_8$). Angular dependent measurements show that the
spin-lattice relaxation time is longer when the magnetic field is perpendicular
to the graphene layer as compared to when the magnetic field is in the plane.
This anisotropy is analyzed in the framework of the Elliott-Yafet theory of
spin-relaxation in metals. The analysis considers an anisotropic spin-orbit
Hamiltonian and the first order perturbative treatment of Elliott is reproduced
for this model Hamiltonian. The result provides an experimental input for the
first-principles theories of spin-orbit interaction in layered carbon and thus
to a better understanding of spin-relaxation phenomena in graphene and in other
layered materials as well.


title:
General phase transition models for vehicular traffic with point
  constraints on the flow

abstract:
  We generalize the phase transition model studied in [R. Colombo. Hyperbolic
phase transition in traffic flow.\ SIAM J.\ Appl.\ Math., 63(2):708-721, 2002],
that describes the evolution of vehicular traffic along a one-lane road. Two
different phases are taken into account, according to whether the traffic is
low or heavy. The model is given by a scalar conservation law in the
\emph{free-flow} phase and by a system of two conservation laws in the
\emph{congested} phase. In particular, we study the resulting Riemann problems
in the case a local point constraint on the flux of the solutions is enforced.


title: Determination of $\Lambda_{\bar{MS}}$ at five loops from holographic QCD

abstract:
  The recent determination of the $\beta$--function of the QCD running coupling
$\alpha_{\overline{MS}}(Q^2)$ to 5-loops{\color{blue},} provides a verification
of the convergence of a novel method for determining the fundamental QCD
parameter $\Lambda_s$ based on the Light-Front Holographic approach to
nonperturbative QCD. The new 5-loop analysis, together with improvements in
determining the holographic QCD nonperturbative scale parameter $\kappa$ from
hadronic spectroscopy, leads to an improved precision of the value of
$\Lambda_s$ in the ${\overline{MS}}$ scheme close to a factor of two; we find
$\Lambda^{(3)}_{\overline{MS}}=0.339\pm0.019$ GeV for $n_{f}=3$, in excellent
agreement with the world average, $\Lambda_{\overline{MS}}^{(3)}=0.332\pm0.017$
GeV. We also discuss the constraints imposed on the scale dependence of the
strong coupling in the nonperturbative domain by superconformal quantum
mechanics and its holographic embedding in anti-de Sitter space.


title:
Portrait of a Dark Horse: a Photometric and Spectroscopic Study of the
  Ultra-faint Milky Way Satellite Pegasus III

abstract:
  Pegasus III (Peg III) is one of the few known ultra-faint stellar systems in
the outer halo of the Milky Way. We present the results from a follow-up
campaign with Magellan/IMACS and Keck/DEIMOS. Deep stellar photometry down to
$r_0\approx 25$ mag at 50% completeness level has allowed accurate measurements
of its photometric and structural properties. The color-magnitude diagram of
Peg III confirms that the stellar system is well described by an old
($\gtrsim12$ Gyr) and metal-poor ([Fe/H]$\lesssim-2.0$ dex) stellar population
at a heliocentric distance of $215\pm12$ kpc. The revised half-light radius
$r_{h}=53\pm14$ pc, ellipticity $\epsilon=0.38^{+0.22}_{-0.38}$, and total
luminosity $M_{V}=-3.4\pm0.4$ are in good agreement with the values quoted in
our previous paper. We further report on the spectroscopic identification of
seven, possibly eight member stars of Peg III. The Ca II triplet lines of the
brightest member stars indicate that Peg III contains stars with metallicity as
low as [Fe/H]=$-2.55\pm0.15$ dex. Peg III has a systemic velocity of $-222.9
\pm 2.6$ km s$^{-1}$ and a velocity dispersion of $5.4^{+3.0}_{-2.5}$ km
s$^{-1}$. The inferred dynamical mass within the half-light radius is
$1.4^{+3.0}_{-1.1} \times 10^6\rm{M_{\odot}}$ and the mass-to-light ratio
$\rm{M/L}$$_{V} = 1470^{+5660}_{-1240}$ $\rm{M_{\odot}/L_{\odot}}$, providing
further evidence that Peg III is a dwarf galaxy satellite. We find that Peg III
and another distant dwarf satellite Pisces II lie relatively close to each
other ($\Delta d_{spatial}=43\pm19$ kpc) and share similar radial velocities in
the Galactic standard-of-rest frame ($\Delta v_{GSR}=12.3\pm3.7$ km s$^{-1}$).
This suggests that they may share a common origin.


title: Identification of interictal epileptic networks from dense-EEG

abstract:
  Epilepsy is a network disease. The epileptic network usually involves
spatially distributed brain regions. In this context, noninvasive M/EEG source
connectivity is an emerging technique to identify functional brain networks at
cortical level from noninvasive recordings. In this paper, we analyze the
effect of the two key factors involved in EEG source connectivity processing:
i) the algorithm used in the solution of the EEG inverse problem and ii) the
method used in the estimation of the functional connectivity. We evaluate four
inverse solutions algorithms and four connectivity measures on data simulated
from a combined biophysical/physiological model to generate realistic
interictal epileptic spikes reflected in scalp EEG. We use a new network-based
similarity index (SI) to compare between the network identified by each of the
inverse/connectivity combination and the original network generated in the
model. The method will be also applied on real data recorded from one epileptic
patient who underwent a full presurgical evaluation for drug-resistant focal
epilepsy. In simulated data, results revealed that the selection of the
inverse/connectivity combination has a significant impact on the identified
networks. Results suggested that nonlinear methods for measuring the
connectivity are more efficient than the linear one. The wMNE inverse solution
showed higher performance than dSPM, cMEM and sLORETA. In real data, the
combination (wMNE/PLV) led to a very good matching between the interictal
epileptic network identified from noninvasive EEG recordings and the network
obtained from connectivity analysis of intracerebral EEG recordings. These
results suggest that source connectivity method, when appropriately configured,
is able to extract highly relevant diagnostic information about networks
involved in interictal epileptic spikes from non-invasive dense-EEG data.


title:
The hyperelliptic mapping class group of a nonorientable surface of
  genus $g\geq 4$ has a faithful representation into $GL(g^2-1,\mathbb{R})$

abstract:
  We prove that the hyperelliptic mapping class group of a nonorientable
surface of genus $g\geq 4$ has a faithful linear representation of dimension
$g^2-1$ over $\mathbb{R}$.


title: Hydrodynamic Limit For An Active Exclusion Process

abstract:
  Collective dynamics can be observed among many animal species, and have given
rise in the last decades to an active and interdisciplinary field of study.
Such behaviors are often modeled by active matter, in which each individual is
self-driven and tends to update its velocity depending on the one of its
neighbors.
  In a classical model introduced by Vicsek and al., as well as in numerous
related active matter models, a phase transition between chaotic behavior at
high temperature and global order at low temperature can be observed. Even
though ample evidence of these phase transitions has been obtained for
collective dynamics, from a mathematical standpoint, such active systems are
not fully understood yet. Significant progress has been achieved in the recent
years under an assumption of mean-field interactions, however to this day, few
rigorous results have been obtained for models involving purely local
interactions.
  In this paper, as a first step towards the mathematical understanding of
active microscopic dynamics, we describe a lattice active particle system, in
which particles interact locally to align their velocities. We obtain
rigorously, using the formalism developed for hydrodynamic limits of lattice
gases, the scaling limit of this out-of-equilibrium system.
  This article builds on the multi-type exclusion model introduced by Quastel
by detailing his proof and incorporating several generalizations, adding
significant technical and phenomenological difficulties.


title: Doped carbon nanotubes as a model system of biased graphene

abstract:
  Albeit difficult to access experimentally, the density of states (DOS) is a
key parameter in solid state systems which governs several important phenomena
including transport, magnetism, thermal, and thermoelectric properties. We
study DOS in an ensemble of potassium intercalated single-wall carbon nanotubes
(SWCNT) and show using electron spin resonance spectroscopy that a sizeable
number of electron states are present, which gives rise to a Fermi-liquid
behavior in this material. A comparison between theoretical and the
experimental DOS indicates that it does not display significant correlation
effects, even though the pristine nanotube material shows a Luttinger-liquid
behavior. We argue that the carbon nanotube ensemble essentially maps out the
whole Brillouin zone of graphene thus it acts as a model system of biased
graphene.


title:
Spectrum of multi-region-relaxed magnetohydrodynamic modes in
  topologically toroidal geometry

abstract:
  A general formulation of the problem of calculating the spectrum of stable
and unstable eigenmodes of linearized perturbations about a magnetically
confined toroidal plasma is presented. The analysis is based on a new
hydromagnetic dynamical model, Multi-region Relaxed Magnetohydrodynamics
(MRxMHD), which models the plasma-magnetic field system as consisting of
multiple regions, containing compressible Euler fluid and Taylor-relaxed
magnetic field, separated by flexible ideal-MHD current sheets. This is
illustrated using a first-principles analysis of a two-region slab geometry,
with periodic boundary conditions to model the outer regions of typical tokamak
or reversed-field pinch plasmas. The lowest and second-lowest eigenvalues in
plasmas unstable to tearing and kink-tearing modes are calculated. Very near
marginal stability the lowest mode obtained using the incompressible
approximation to the kinetic energy normalization of the present study is shown
to correspond to the eigenvalues found in previous studies with less physical
normalizations.


title:
Role of particle masses in the magnetic field generation driven by the
  parity violating interaction

abstract:
  Recently the new model for the generation of strong large scale magnetic
fields in neutron stars, driven by the parity violating interaction, was
proposed. In this model, the magnetic field instability results from the
modification of the chiral magnetic effect in presence of the electroweak
interaction between ultrarelativistic electrons and nucleons. In the present
work we study how a nonzero mass of charged particles, which are degenerate
relativistic electrons and nonrelativistic protons, influences the generation
of the magnetic field in frames of this approach. For this purpose we calculate
the induced electric current of these charged particles, electroweakly
interacting with background neutrons and an external magnetic field, exactly
accounting for the particle mass. This current is calculated by two methods:
using the exact solution of the Dirac equation for a charged particle in
external fields and computing the polarization operator of a photon in matter
composed of background neutrons. We show that the induced current is vanishing
in both approaches leading to the zero contribution of massive particles to the
generated magnetic field. We discuss the implication of our results for the
problem of the magnetic field generation in compact stars.


title: Bounding Solutions of a Forced Oscillator

abstract:
  Our proof is based on a generalization of action-angle variables, a
convergent Lie transformation, and Moser's invariant curve theorem. As an
overall outline we give a quick proof of Morris' original theorem. Then the
full theorem is established in two steps. In the first step we define a special
case and then follow the proof given for Morris' Theorem to prove boundedness
for the special case. In the second step we use the method of Lie transforms to
reduce the general case to the special case.


title:
Pion transverse-momentum spectrum, elliptic flow, and
  Hanbury-Brown-Twiss interferometry in a viscous granular source model

abstract:
  We examine the evolution of quark-gluon plasma (QGP) droplets with viscous
hydrodynamics and analyze the pion transverse-momentum spectrum, elliptic flow,
and Hanbury-Brown-Twiss (HBT) interferometry in a granular source model
consisting of viscous QGP droplets. The shear viscosity of the QGP droplet
speeds up and slows down the droplet evolution in the central and peripheral
regions of the droplet, respectively. The effect of the bulk viscosity on the
evolution is negligible. Although there are viscous effects on the droplet
evolution, the pion momentum spectrum and elliptic flow change little for
granular sources with and without viscosity. On the other hand, the influence
of viscosity on HBT radius $R_{\rm out}$ is considerable. It makes $R_{\rm
out}$ decrease in the granular source model. We determine the model parameters
of granular sources using the experimental data of pion transverse-momentum
spectrum, elliptic flow, and HBT radii together, and investigate the effects of
viscosity on the model parameters. The results indicate that the granular
source model may reproduce the experimental data of pion transverse-momentum
spectrum, elliptic flow, and HBT radii in heavy-ion collisions of Au-Au at
$\sqrt{s_{NN}}=200$ GeV and Pb-Pb at $\sqrt{s_{NN}}=2.76$ TeV in different
centrality intervals. The viscosity of the droplet leads to an increase in the
initial droplet radius and a decrease of the source shell parameter in the
granular source model.


title:
Demystifying Competition and Cooperation Dynamics of the Aerial mmWave
  Access Market

abstract:
  Cellular has always relied on static deployments for providing wireless
access. However, even the emerging fifth-generation (5G) networks may face
difficulty in supporting the increased traffic demand with rigid, fixed
infrastructure without substantial over-provisioning. This is particularly true
for spontaneous large-scale events that require service providers to augment
capacity of their networks quickly. Today, the use of aerial devices equipped
with high-rate radio access capabilities has the potential to offer the much
needed "on-demand" capacity boost. Conversely, it also threatens to rattle the
long-standing business strategies of wireless operators, especially as the
"gold rush" for cheaper millimeter wave (mmWave) spectrum lowers the market
entry barriers. However, the intricate structure of this new market presently
remains a mystery. This paper sheds light on competition and cooperation
behavior of dissimilar aerial mmWave access suppliers, concurrently employing
licensed and license-exempt frequency bands, by modeling it as a vertically
differentiated market where customers have varying preferences in price and
quality. To understand viable service provider strategies, we begin with
constructing the Nash equilibrium for the initial market competition by
employing the Bertrand and Cournot games. We then conduct a unique assessment
of short-term market dynamics, where two licensed-band service providers may
cooperate to improve their competition positions against the unlicensed-band
counterpart intruding the market. Our unprecedented analysis studies the
effects of various market interactions, price-driven demand evolution, and
dynamic profit balance in this novel type of ecosystem.


title: Examples of Ricci-mean curvature flows

abstract:
  Let $\pi:\mathbb{P}(\mathcal{O}(0)\oplus \mathcal{O}(k))\to \mathbb{P}^{n-1}$
be a projective bundle over $\mathbb{P}^{n-1}$ with $1\leq k \leq n-1$. In this
paper, we show that lens space $L(k\, ;1)(r)$ with radius $r$ embedded in
$\mathbb{P}(\mathcal{O}(0)\oplus \mathcal{O}(k))$ is a self-similar solution,
where $\mathbb{P}(\mathcal{O}(0)\oplus \mathcal{O}(k))$ is endowed with the
$U(n)$-invariant gradient shrinking Ricci soliton structure. We also prove that
there exists a pair of critical radii $r_{1}<r_{2}$ which satisfies the
following. The lens space $L(k\, ;1)(r)$ is a self-shrinker if $r<r_{2}$ and
self-expander if $r_{2}<r$, and the Ricci-mean curvature flow emanating from
$L(k\, ;1)(r)$ collapses to the zero section of $\pi$ if $r<r_{1}$ and to the
$\infty$-section of $\pi$ if $r_{1}<r$. This gives explicit examples of
Ricci-mean curvature flows.


title: A Note on Koldobsky's Lattice Slicing Inequality

abstract:
  $ \newcommand{\R}{{\mathbb{R}}} \newcommand{\Z}{{\mathbb{Z}}}
\renewcommand{\vec}[1]{{\mathbf{#1}}} $We show that if $K \subset \R^d$ is an
origin-symmetric convex body, then there exists a vector $\vec{y} \in \Z^d$
such that \begin{align*} |K \cap \Z^d \cap \vec{y}^\perp| / |K \cap \Z^d| \ge
\min(1,c \cdot d^{-1} \cdot \mathrm{vol}(K)^{-1/(d-1)}) \; , \end{align*} for
some absolute constant $c> 0$, where $\vec{y}^\perp$ denotes the subspace
orthogonal to $\vec{y}$. This gives a partial answer to a question by
Koldobsky.


title:
Generation of strong magnetic fields in dense quark matter driven by the
  electroweak interaction of quarks

abstract:
  We study the generation of strong large scale magnetic fields in dense quark
matter. The magnetic field growth is owing to the magnetic field instability
driven by the electroweak interaction of quarks. We discuss the situation when
the chiral symmetry is unbroken in the degenerate quark matter. In this case we
predict the amplification of the seed magnetic field $10^{12}\,\text{G}$ to the
strengths $(10^{14}-10^{15})\,\text{G}$. In our analysis we use the typical
parameters of the quark matter in the core of a hybrid star or in a quark star.
We also discuss the application of the obtained results to describe the
magnetic fields generation in magnetars.


title: Quasi-normality induced by differential inequalities

abstract:
  We show that the family ${\cal F}_k$ of all meromorphic functions $f$ in a
domain $D$ satisfying $$\frac{|f^{(k)}|}{1+|f|}(z)\ge C \qquad \mbox{ for all }
z\in D$$ (where $k$ is a natural number and $C>0$) is quasi-normal. The proof
relies mainly on the Zalcman-Pang rescaling method.


title: TASI lectures on AdS/CFT

abstract:
  We introduce the AdS/CFT correspondence as a natural extension of QFT in a
fixed AdS background. We start by reviewing some general concepts of CFT,
including the embedding space formalism. We then consider QFT in a fixed AdS
background and show that one can define boundary operators that enjoy very
similar properties as in a CFT, except for the lack of a stress tensor.
Including a dynamical metric in AdS generates a boundary stress tensor and
completes the CFT axioms. We also discuss some applications of the bulk
geometric intuition to strongly coupled QFT. Finally, we end with a review of
the main properties of Mellin amplitudes for CFT correlation functions and
their uses in the context of AdS/CFT.


title:
The mass-ratio and eccentricity distributions of barium and S stars, and
  red giants in open clusters

abstract:
  In order to identify diagnostics distinguishing between pre- and
post-mass-transfer systems, the mass-ratio distribution and period -
eccentricity (P - e) diagram of barium and S stars are compared to those of the
sample of binary red giants in open clusters from Mermilliod et al. (2007).
  From the analysis of the mass-ratio distribution for the cluster binary
giants, we find an excess of systems with companion masses between 0.58 and
0.87 Msun, typical for white dwarfs. They represent 22% of the sample, which
are thus candidate post-mass-transfer systems. Among these candidates which
occupy the same locus as the barium and S stars in the (P-e) diagram, only 33%
(= 4/12) show a chemical signature of mass transfer in the form of s-process
overabundances (from rather moderate -- about 0.3 dex -- to more extreme --
about 1 dex). These s-process-enriched cluster stars show a clear tendency to
be in the clusters with the lowest metallicity in the sample, confirming the
classical prediction that the s-process nucleosynthesis is more efficient at
low metallicities (the only strong barium star in our sample is found in the
cluster with the lowest metallicity, i.e., star 173 in NGC 2420, with [Fe/H] =
-0.26). The s-process overabundance is not clearly correlated with the cluster
turnoff (TO) mass (such a correlation would instead hint at the importance of
the dilution factor). We find as well a mild barium star in NGC 2335, a cluster
with a large TO mass of 4.3 Msun, which implies that intermediate-mass AGB
stars still operate the s-process and the third dredge-up.


title: Relaxation of the chiral imbalance in dense matter of a neutron star

abstract:
  Using the quantum field theory methods, we calculate the helicity flip of an
electron scattering off protons in dense matter of a neutron star. The
influence of the electroweak interaction between electrons and background
nucleons on the helicity flip is examined. We also derive the kinetic equation
for the chiral imbalance. The derived kinetic equation is compared with the
results obtained by other authors.


title:
Red giants observed by CoRoT and APOGEE: The evolution of the Milky
  Way's radial metallicity gradient

abstract:
  Using combined asteroseismic and spectroscopic observations of 418 red-giant
stars close to the Galactic disc plane (6 kpc $<R_{\rm Gal}\lesssim13$ kpc,
$|Z_{\rm Gal}|<0.3$ kpc), we measure the age dependence of the radial
metallicity distribution in the Milky Way's thin disc over cosmic time. The
slope of the radial iron gradient of the young red-giant population
($-0.058\pm0.008$ [stat.] $\pm0.003$ [syst.] dex/kpc) is consistent with recent
Cepheid measurements. For stellar populations with ages of $1-4$ Gyr the
gradient is slightly steeper, at a value of $-0.066\pm0.007\pm0.002$ dex/kpc,
and then flattens again to reach a value of $\sim-0.03$ dex/kpc for stars with
ages between 6 and 10 Gyr. Our results are in good agreement with a
state-of-the-art chemo-dynamical Milky-Way model in which the evolution of the
abundance gradient and its scatter can be entirely explained by a non-varying
negative metallicity gradient in the interstellar medium, together with stellar
radial heating and migration. We also offer an explanation for why
intermediate-age open clusters in the Solar Neighbourhood can be more
metal-rich, and why their radial metallicity gradient seems to be much steeper
than that of the youngest clusters. Already within 2 Gyr, radial mixing can
bring metal-rich clusters from the innermost regions of the disc to
Galactocentric radii of 5 to 8 kpc. We suggest that these outward-migrating
clusters may be less prone to tidal disruption and therefore steepen the local
intermediate-age cluster metallicity gradient. Our scenario also explains why
the strong steepening of the local iron gradient with age is not seen in field
stars. In the near future, asteroseismic data from the K2 mission will allow
for improved statistics and a better coverage of the inner-disc regions,
thereby providing tighter constraints on the evolution of the central parts of
the Milky Way.


title:
Superiorization of Incremental Optimization Algorithms for Statistical
  Tomographic Image Reconstruction

abstract:
  We propose the superiorization of incremental algorithms for tomographic
image reconstruction. The resulting methods follow a better path in its way to
finding the optimal solution for the maximum likelihood problem in the sense
that they are closer to the Pareto optimal curve than the non-superiorized
techniques. A new scaled gradient iteration is proposed and three
superiorization schemes are evaluated. Theoretical analysis of the methods as
well as computational experiments with both synthetic and real data are
provided.


title: A Perceptual Aesthetics Measure for 3D Shapes

abstract:
  While the problem of image aesthetics has been well explored, the study of 3D
shape aesthetics has focused on specific manually defined features. In this
paper, we learn an aesthetics measure for 3D shapes autonomously from raw voxel
data and without manually-crafted features by leveraging the strength of deep
learning. We collect data from humans on their aesthetics preferences for
various 3D shape classes. We take a deep convolutional 3D shape ranking
approach to compute a measure that gives an aesthetics score for a 3D shape. We
demonstrate our approach with various types of shapes and for applications such
as aesthetics-based visualization, search, and scene composition.


title: Measurement of the underlying-event properties with the ATLAS detector

abstract:
  A correct modelling of the underlying event in proton-proton collisions is
important for the proper simulation of kinematic distributions of high-energy
collisions. The ATLAS collaboration extended previous studies at 7 TeV with a
leading track or jet or Z boson by a new study of Drell-Yan events in 1.1 1/fb
of data collected at a center-of-mass energy of 7 TeV. In this new study the
distributions of several topological event-shape variables based on charged
particles are measured, both integrated and differential in the transverse
momentum of the Drell-Yan lepton pair. These measurements are sensitive to the
underlying-event as well as the onset of hard emissions. The results have been
compared with the predictions of several state-of-the-art MC generators. The
collaboration has also performed a first study of the number and transverse
momentum sum of charged particles as a function of transverse momentum and
azimuthal angle in a special data set taken with low beam currents at a
center-of-mass energy of 13 TeV. The results are compared to predictions of
several MC generators.


title:
An Alternative Distributed Control Architecture for Improvement in the
  Transient Response of DC Microgrids

abstract:
  Distributed secondary control plays an important role in DC microgrids, since
it ensures system control objectives, which are power sharing and DC bus
voltage stability. Previous studies have suggested using a control architecture
that utilizes a parallel secondary bus voltage and current sharing
compensation. However, the parallel controllers have a mutual impact on each
other, which degrades the transient performance of the system. This paper
reports on an alternative distributed secondary control architecture and
controller design process, based on small signal analysis to alleviate the
mutual effect of the current sharing and bus voltage compensation, and to
improve the transient response of the system. Experimental results confirm the
improved transient performance in the current sharing control and DC bus
voltage stability utilizing the proposed control architecture.


title:
PT-Symmetry Breaking and Catastrophes in Dissipationless Resonant
  Tunneling Heterostructures

abstract:
  We study the phenomenon of spontaneous symmetry breaking in dissipationless
resonant tunneling heterostructures (RTS). To describe the quantum transport in
this system we apply both the nonequilibrium Green function formalism based on
a tight-binding model and a numerical solution of the Schroedinger equation
within the envelope wavefunction formalism. An auxiliary non-Hermitian
Hamiltonian is introduced. Its eigenvalues determine exactly the transparency
peak positions. We present a procedure how to construct a family of
non-Hermitian Hamiltonians with real eigenvalues. In general these Hamiltonians
do not have PT-symmetry. In spatially symmetric RTS the corresponding auxiliary
non-Hermitian Hamiltonian becomes PT-symmetric and possesses real eigenvalues,
which can coalesce at exceptional points (EP) of Hamiltonian. A coalescence of
the auxiliary non-Hermitian Hamiltonian eigenvalues means a coalescence of
resonances in RTS, which is accompanied be symmetry breaking of the electron
wavefunction probability distribution (at a given direction of the particle
flow). We construct a classification of different types of the peak coalescence
in terms of the catastrophe theory and investigate the impact of dissipation
and asymmetry on these phenomena. Possible applications include sensors and
broad-band filters.


title:
Size Dependence of Oxygen-annealing Effects on Superconductivity of
  Fe{1+y}Te{1-x}S{x}

abstract:
  For the Fe-based superconductor Fe{1+y}Te{1-x}S{x}, superconductivity is
induced by annealing treatment in oxygen atmosphere, whereas as-grown samples
do not show superconductivity. We have investigated the sample-size dependence
of O2-annealing effects in Fe1.01Te0.91S0.09. The annealing conditions are
fixed to be 1 atm, 200 C, and 2 hours. We have carried out magnetic
susceptibility and specific heat measurements in order to evaluate the
superconducting volume fraction. We have found that Fe{1+y}Te{1-x}S{x} has an
optimal size for the induction of bulk superconductivity by O2 annealing. Our
results indicate that O2 annealing is probably effective near the surface of
samples over a length of a few tens of micro meters.


title:
Mediation Analysis for Censored Survival Data under an Accelerated
  Failure Time Model

abstract:
  Recent advances in causal mediation analysis have formalized conditions for
estimating direct and indirect effects in various contexts. These approaches
have been extended to a number of models for survival outcomes including
accelerated failure time (AFT) models which are widely used in a broad range of
health applications given their intuitive interpretation. In this setting, it
has been suggested that under standard assumptions, the "difference" and
"product" methods produce equivalent estimates of the indirect effect of
exposure on the survival outcome. We formally show that these two methods may
produce substantially different estimates in the presence of censoring or
truncation, due to a form of model misspecification. Specifically, we establish
that while the product method remains valid under standard assumptions in the
presence of independent censoring, the difference method can be biased in the
presence of such censoring whenever the error distribution of the AFT model
fails to be collapsible upon marginalizing over the mediator. This will
invariably be the case for most choices of mediator and outcome error
distributions. A notable exception arises in case of normal mediator-normal
outcome where we show consistency of both difference and product estimators in
the presence of independent censoring. These results are confirmed in
simulation studies and two data applications.


title:
Frame- and Segment-Level Features and Candidate Pool Evaluation for
  Video Caption Generation

abstract:
  We present our submission to the Microsoft Video to Language Challenge of
generating short captions describing videos in the challenge dataset. Our model
is based on the encoder--decoder pipeline, popular in image and video
captioning systems. We propose to utilize two different kinds of video
features, one to capture the video content in terms of objects and attributes,
and the other to capture the motion and action information. Using these diverse
features we train models specializing in two separate input sub-domains. We
then train an evaluator model which is used to pick the best caption from the
pool of candidates generated by these domain expert models. We argue that this
approach is better suited for the current video captioning task, compared to
using a single model, due to the diversity in the dataset.
  Efficacy of our method is proven by the fact that it was rated best in MSR
Video to Language Challenge, as per human evaluation. Additionally, we were
ranked second in the automatic evaluation metrics based table.


title:
Entanglement entropy and massless phase in the antiferromagnetic
  three-state quantum chiral clock model

abstract:
  The von Neumann entanglement entropy is used to estimate the critical point
$h_c/J \simeq 0.143(3)$ of the mixed ferro-antiferromagnetic three-state
quantum Potts model $H = \sum_i [ J ( X_i X_{i+1}^{\,2} + X_i^{\,2} X_{i+1} ) -
h\, R_i ]$, where $X_i$ and $R_i$ are standard three-state Potts spin operators
and $J>0$ is the antiferromagnetic coupling parameter. This critical point
value gives improved estimates for two Kosterlitz-Thouless transition points in
the antiferromagnetic ($\beta < 0$) region of the $\Delta$--$\beta$ phase
diagram of the three-state quantum chiral clock model, where $\Delta$ and
$\beta$ are, respectively, the chirality and coupling parameters in the clock
model. These are the transition points $\beta_c \simeq - 0.143(3)$ at $\Delta =
\frac12$ between incommensurate and commensurate phases and $\beta_c \simeq -
7.0(1)$ at $\Delta = 0$ between disordered and incommensurate phases. The von
Neumann entropy is also used to calculate the central charge $c$ of the
underlying conformal field theory in the massless phase $h \le h_c$. The
estimate $c \simeq 1$ in this phase is consistent with the known exact value at
the particular point $h/J = -1$ corresponding to the purely antiferromagnetic
three-state quantum Potts model. The algebraic decay of the Potts spin-spin
correlation in the massless phase is used to estimate the continuously varying
critical exponent $\eta$.


title:
Clustering Mixed Datasets Using Homogeneity Analysis with Applications
  to Big Data

abstract:
  Datasets with a mixture of numerical and categorical attributes are routinely
encountered in many application domains. In this work we examine an approach to
clustering such datasets using homogeneity analysis. Homogeneity analysis
determines a euclidean representation of the data. This can be analyzed by
leveraging the large body of tools and techniques for data with a euclidean
representation. Experiments conducted as part of this study suggest that this
approach can be useful in the analysis and exploration of big datasets with a
mixture of numerical and categorical attributes.


title:
Stimulated Brillouin scattering enhancement in silicon inverse opal
  waveguides

abstract:
  Silicon is an ideal material for on-chip applications, however its poor
acoustic properties limit its performance for important optoacoustic
applications, particularly for Stimulated Brillouin Scattering (SBS). We
theoretically show that silicon inverse opals exhibit a strongly improved
acoustic performance that enhances the bulk SBS gain coefficient by more than
two orders of magnitude. We also design a waveguide that incorporates silicon
inverse opals and which has SBS gain values that are comparable with
chalcogenide glass waveguides. This research opens new directions for
opto-acoustic applications in on-chip material systems.


title: Brochette percolation

abstract:
  We study bond percolation on the square lattice with one-dimensional
inhomogeneities. Inhomogeneities are introduced in the following way: A
vertical column on the square lattice is the set of vertical edges that project
to the same vertex on $\mathbb{Z}$. Select vertical columns at random
independently with a given positive probability. Keep (respectively remove)
vertical edges in the selected columns, with probability $p$, (respectively
$1-p$). All horizontal edges and vertical edges lying in unselected columns are
kept (respectively removed) with probability $q$, (respectively $1-q$). We show
that, if $p > p_c(\mathbb{Z}^2)$ (the critical point for homogeneous Bernoulli
bond percolation) then $q$ can be taken strictly smaller then
$p_c(\mathbb{Z}^2)$ in such a way that the probability that the origin
percolates is still positive.


title:
Herschel/PACS far-IR spectral imaging of a jet from an intermediate mass
  protostar in the OMC-2 region

abstract:
  We present the first detection of a jet in the far-IR [O I] lines from an
intermediate mass protostar. We have carried out a Herschel/PACS spectral
mapping study in the [O I] lines of OMC-2 FIR 3 and FIR 4, two of the most
luminous protostars in Orion outside of the Orion Nebula. The spatial
morphology of the fine structure line emission reveals the presence of an
extended photodissociation region (PDR) and a narrow, but intense jet
connecting the two protostars. The jet seen in [O I] emission is spatially
aligned with the Spitzer/IRAC 4.5 micron jet and the CO (6-5) molecular outflow
centered on FIR 3. The mass loss rate derived from the total [O I] 63 micron
line luminosity of the jet is 7.7 x 10^-6 M_sun/yr, more than an order of
magnitude higher than that measured for typical low mass class 0 protostars.
The implied accretion luminosity is significantly higher than the observed
bolometric luminosity of FIR 4, indicating that the [O I] jet is unlikely to be
associated with FIR 4. We argue that the peak line emission seen toward FIR 4
originates in the terminal shock produced by the jet driven by FIR 3. The
higher mass-loss rate that we find for FIR 3 is consistent with the idea that
intermediate mass protostars drive more powerful jets than their low-mass
counterparts. Our results also call into question the nature of FIR 4.


title: The evolution of far-infrared CO emission from protostars

abstract:
  We investigate the evolution of far-IR CO emission from protostars observed
with Herschel/PACS for 50 sources from the combined sample of HOPS and DIGIT
Herschel key programs. From the uniformly sampled spectral energy
distributions, we computed $L_{\rm{bol}}$, $T_{\rm{bol}}$ and $L_{\rm
{bol}}/L_{\rm {smm}}$ for these sources to search for correlations between
far-IR CO emission and protostellar properties. We find a strong and tight
correlation between far-IR CO luminosity ($L^{\rm fir}_{\rm CO}$) and the
bolometric luminosity ($L_{\rm{bol}}$) of the protostars with $L^{\rm fir}_{\rm
CO}$ $\propto$ $L_{\rm{bol}}^{0.7}$. We, however, do not find a strong
correlation between $L^{\rm fir}_{\rm CO}$ and protostellar evolutionary
indicators, $T_{\rm{bol}}$ and $L_{\rm {bol}}/L_{\rm {smm}}$. FIR CO emission
from protostars traces the currently shocked gas by jets/outflows, and $L^{\rm
fir}_{\rm CO}$ is proportional to the instantaneous mass loss rate,
$\dot{M}_{\rm{out}}$. The correlation between $L^{\rm fir}_{\rm CO}$ and
$L_{\rm{bol}}$ is indicative of instantaneous $\dot{M}_{\rm{out}}$ tracking
instantaneous $\dot{M}_{\rm{acc}}$. The lack of correlation between $L^{\rm
fir}_{\rm CO}$ and evolutionary indicators $T_{\rm{bol}}$ and $L_{\rm
{bol}}/L_{\rm {smm}}$ suggests that $\dot{M}_{\rm{out}}$ and, therefore,
$\dot{M}_{\rm{acc}}$ do not show any clear evolutionary trend. These results
are consistent with mass accretion/ejection in protostars being episodic. Taken
together with the previous finding that the time-averaged mass
ejection/accretion rate declines during the protostellar phase (e.g., Bontemps
et al. 1996), our results suggest that the instantaneous accretion/ejection
rate of protostars is highly time variable and episodic, but the amplitude
and/or frequency of this variability decreases with time such that the time
averaged accretion/ejection rate declines with system age.


title: Vibrational dephasing in matter-wave interferometers

abstract:
  Matter-wave interferometry is a highly sensitive tool to measure small
perturbations in a quantum system. This property allows the creation of
precision sensors for dephasing mechanisms such as mechanical vibrations. They
are a challenge for phase measurements under perturbing conditions that cannot
be perfectly decoupled from the interferometer, e.g. for mobile interferometric
devices or vibrations with a broad frequency range. Here, we demonstrate a
method based on second-order correlation theory in combination with Fourier
analysis, to use an electron interferometer as a sensor that precisely
characterizes the mechanical vibration spectrum of the interferometer. Using
the high spatial and temporal single-particle resolution of a delay line
detector, the data allows to reveal the original contrast and spatial
periodicity of the interference pattern from "washed-out" matter-wave
interferograms that have been vibrationally disturbed in the frequency region
between 100 and 1000 Hz. Other than with electromagnetic dephasing, due to
excitations of higher harmonics and additional frequencies induced from the
environment, the parts in the setup oscillate with frequencies that can be
different to the applied ones. The developed numerical search algorithm is
capable to determine those unknown oscillations and corresponding amplitudes.
The technique can identify vibrational dephasing and decrease damping and
shielding requirements in electron, ion, neutron, atom and molecule
interferometers that generate a spatial fringe pattern on the detector plane.


title:
The BioDynaMo Project: Creating a Platform for Large-Scale Reproducible
  Biological Simulations

abstract:
  Computer simulations have become a very powerful tool for scientific
research. In order to facilitate research in computational biology, the
BioDynaMo project aims at a general platform for biological computer
simulations, which should be executable on hybrid cloud computing systems. This
paper describes challenges and lessons learnt during the early stages of the
software development process, in the context of implementation issues and the
international nature of the collaboration.


title:
Motivic HyperK\"ahler Resolution Conjecture : I. Generalized Kummer
  varieties

abstract:
  Given a smooth projective variety $M$ endowed with a faithful action of a
finite group $G$, following Jarvis-Kaufmann-Kimura and Fantechi-G\"ottsche, we
define the orbifold motive (or Chen-Ruan motive) of the quotient stack $[M/G]$
as an algebra object in the category of Chow motives. Inspired by Ruan, one can
formulate a motivic version of his Cohomological HyperK\"ahler Resolution
Conjecture. We prove this motivic version, as well as its K-theoretic analogue
conjectured by Jarvis-Kaufmann-Kimura, in two situations related to an abelian
surface $A$ and a positive integer $n$. Case (A) concerns Hilbert schemes of
points of $A$ : the Chow motive of $A^{[n]}$ is isomorphic as algebra objects,
up to a suitable sign change, to the orbifold motive of the quotient stack
$[A^{n}/\mathfrak{S}_{n}]$. Case (B) for generalized Kummer varieties : the
Chow motive of the generalized Kummer variety $K_n(A)$ is isomorphic as algebra
objects, up to a suitable sign change, to the orbifold motive of the quotient
stack $[A_{0}^{n+1}/\mathfrak {S}_{n+1}]$, where $A_{0}^{n+1}$ is the kernel
abelian variety of the summation map $A^{n+1}\to A$. As a byproduct, we prove
the original Cohomological HyperK\"ahler Resolution Conjecture for generalized
Kummer varieties. As an application, we provide multiplicative Chow-K\"unneth
decompositions for Hilbert schemes of abelian surfaces and for generalized
Kummer varieties. In particular, we have a multiplicative direct sum
decomposition of their Chow rings with rational coefficients, which is expected
to be the splitting of the conjectural Bloch-Beilinson-Murre filtration. The
existence of such a splitting for holomorphic symplectic varieties is
conjectured by Beauville.


title: No evidence for a low-mass black hole in Swift J1753.5-0127

abstract:
  We present high-resolution, time-resolved optical spectroscopy of the black
hole X-ray transient Swift J1753.5-0127. Our optical spectra do not show
features that we can associate with the companion star. However we do observe
broad, double-peaked emission lines, typical of an accretion disc. We show that
the mass of the compact object is likely $>7.4\pm1.2M_{\odot}$, much higher
than previous suggestions of a low-mass ($<5M_{\odot}$) black hole.


title: Real space electrostatics for multipoles. III. Dielectric Properties

abstract:
  In the first two papers in this series, we developed new shifted potential
(SP), gradient shifted force (GSF), and Taylor shifted force (TSF) real-space
methods for multipole interactions in condensed phase simulations. Here, we
discuss the dielectric properties of fluids that emerge from simulations using
these methods. Most electrostatic methods (including the Ewald sum) require
correction to the conducting boundary fluctuation formula for the static
dielectric constants, and we discuss the derivation of these corrections for
the new real space methods. For quadrupolar fluids, the analogous material
property is the quadrupolar susceptibility. As in the dipolar case, the
fluctuation formula for the quadrupolar susceptibility has corrections that
depend on the electrostatic method being utilized. One of the most important
effects measured by both the static dielectric and quadrupolar susceptibility
is the ability to screen charges embedded in the fluid. We use potentials of
mean force between solvated ions to discuss how geometric factors can lead to
distance-dependent screening in both quadrupolar and dipolar fluids.


title:
Acoustic properties of glacial ice for neutrino detection and the
  Enceladus Explorer

abstract:
  Ultra high energy neutrinos may be observed in ice by the emission of
acoustic signals. The SPATS detector has investigated the possibility of
observing GZK-neutrinos in the clear ice near the South Pole at the IceCube
detector site. To explore other potential detection sites glacial ice in the
Alps and in Antarctica has been surveyed for its acoustical properties. The
purpose of the Enceladus Explorer (EnEx), on the other hand, is the search for
extraterrestrial life on the Saturn moon Enceladus. Here acoustics is used to
maneuver a subsurface probe inside the ice by trilateration of signals. A
system of acoustic transducers has been developed to study both applications.
In the south polar region of the moon Enceladus there are secluded crevasses.
These are filled with liquid water, probably heated by tidal forces due to the
short distance to Saturn. We intend to take a sample of water from these
crevasses by using a combination of a melt down and steering probe called
IceMole (IM). Maneuvering IM requires a good understanding of ice properties
such as the speed of sound, the attenuation of acoustic signals in ice, their
directional dependencies and their dependence on different frequencies. The
technology developed for this positioning system could also contribute to the
design of future large scale acoustic neutrino detectors. We present our
analysis methods and the findings on attenuation, sound speed, and frequency
response obtained at several sites in the Alps and Antarctica.


title:
A Three Spatial Dimension Wave Latent Force Model for Describing
  Excitation Sources and Electric Potentials Produced by Deep Brain Stimulation

abstract:
  Deep brain stimulation (DBS) is a surgical treatment for Parkinson's Disease.
Static models based on quasi-static approximation are common approaches for DBS
modeling. While this simplification has been validated for bioelectric sources,
its application to rapid stimulation pulses, which contain more high-frequency
power, may not be appropriate, as DBS therapeutic results depend on stimulus
parameters such as frequency and pulse width, which are related to time
variations of the electric field. We propose an alternative hybrid approach
based on probabilistic models and differential equations, by using Gaussian
processes and wave equation. Our model avoids quasi-static approximation,
moreover, it is able to describe dynamic behavior of DBS. Therefore, the
proposed model may be used to obtain a more realistic phenomenon description.
The proposed model can also solve inverse problems, i.e. to recover the
corresponding source of excitation, given electric potential distribution. The
electric potential produced by a time-varying source was predicted using
proposed model. For static sources, the electric potential produced by
different electrode configurations were modeled. Four different sources of
excitation were recovered by solving the inverse problem. We compare our
outcomes with the electric potential obtained by solving Poisson's equation
using the Finite Element Method (FEM). Our approach is able to take into
account time variations of the source and the produced field. Also, inverse
problem can be addressed using the proposed model. The electric potential
calculated with the proposed model is close to the potential obtained by
solving Poisson's equation using FEM.