title:
Pointwise bounds for positive supersolutions of nonlinear elliptic
  problems involving the $p$-Laplacian and application

abstract:
  We derive a priori bounds for positive supersolutions of $ - \Delta_{p} u =
\rho(x) f(u) $, where $p>1$ and $\Delta_{p}$ is the $p$-Laplace operator, in a
smooth bounded domain of $R^{N}$ with zero Dirichlet boundary conditions. We
apply the results to nonlinear elliptic eigenvalue problem $ - \Delta_{p} u =
\lambda f(u) $, with Dirichlet boundary condition, where $ f $ is a
nondecreasing continuous differentiable function on $[0,\infty]$ such that $
f(0) > 0 $, $ f(t)^{\frac{1}{p-1}} $ is superlinear at infinity, and give sharp
upper and lower bounds for the extremal parameter $ \lambda_{p}^{*} $. In
particular, we consider the nonlinearities $ f(u) = e^u $ and $ f(u) =
(1+u)^{m} $ ($ m > p-1 $) and give explicit estimates on $ \lambda_{p}^{*} $.
As a by-product of our results, we obtain a lower bound for the principal
eigenvalue of the $ p $-Laplacian that improves obtained results in the recent
literature for some range of $ p $ and $ N $.


title: Hall sets, Lazard sets and comma-free codes

abstract:
  We investigate the relationship between two constructions of maximal
comma-free codes described respectively by Eastman and by Scholtz and the
notions of Hall sets and Lazard sets introduced in connection with
factorizations of free monoids and bases of free Lie algebras.


title: Hybrid gold single crystals incorporating amino acids

abstract:
  Composite hybrid gold crystals are of profound interest in various research
areas ranging from materials science to biology. Their importance is due to
their unique properties and potential implementation, for example in sensing or
in bio-nanomedicine. Here we report on the formation of hybrid organic-metal
composites via the incorporation of selected amino acids histidine, aspartic
acid, serine, glutamine, alanine, cysteine, and selenocystine into the crystal
lattice of single crystals of gold. We used electron microscopy, chemical
analysis and high-resolution synchrotron powder X ray diffraction to examine
these composites. Crystal shape, as well as atomic concentrations of occluded
amino acids and their impact on the crystal structure of gold, were determined.
Concentration of the incorporated amino acid was highest for cysteine, followed
by serine and aspartic acid. Our results indicate that the incorporation
process probably occurs through a complex interaction of their individual
functional groups with gold atoms. Although various organic gold composites
have been prepared, to the best of our knowledge this is the first reported
finding of incorporation of organic molecules within the gold lattice. We
present a versatile strategy for fabricating crystalline nanohybrid composite
gold crystals of potential importance for a wide range of applications.


title:
New open cluster Cepheids in the VVV survey tightly constrain
  near-infrared period--luminosity relations

abstract:
  Classical Cepheids are among the most useful Galactic and nearby
extragalactic distance tracers because of their well-defined period--luminosity
relations (PLRs). Open cluster (OC) Cepheids are important objects to
independently calibrate these PLRs. Based on Data Release 1 of the {\sl VISTA}
Variables in the V\'ia L\'actea survey, we have discovered four new, faint and
heavily reddened OC Cepheids, including the longest-period OC Cepheid known,
ASAS J180342$-$2211.0 in Teutsch 14a. The other OC--Cepheid pairs include NGC
6334 and V0470 Sco, Majaess 170 and ASAS J160125$-$5150.3, and Teutsch 77 and
BB Cen. ASAS J180342$-$2211.0, with a period of $\log P = 1.623$ [days] is
important to constrain the slope of the PLR. The currently most complete
$JHK_{\rm s}$ Galactic Cepheid PLRs are obtained based on a significantly
increased sample of 31 OC Cepheids, with associated uncertainties that are
improved by 40 per cent compared with previous determinations (in the $J$
band). The NIR PLRs are in good agreement with previous PLRs determined based
on other methods.


title: Theory of hard probes in PbPb collisions

abstract:
  The jet quenching phenomenon in heavy ion collisions provides a strong
evidence of the modification of parton shower in the quark-gluon plasma. This
contribution focuses on the hard probes of QGP using jets and summarizes the
new theoretical progress of jet substructure modification studies using
effective field theory techniques. We emphasize the important role of jet
substructure observables as they probe various aspects of the jet formation
mechanism and allow us to study the medium properties in great details. The
precise calculations require the systematic resummation and consistently
including medium modifications. Specifically, we discuss the calculations of
jet shapes and cross sections in proton-proton and lead-lead collisions at the
LHC using soft-collinear effective theory, with Glauber gluon interactions in
the medium. In the end we present the comparison between our calculations and
the recent measurements at the LHC with very good agreement. We conclude that
precise jet modification studies in heavy ion collisions has been initiated.


title: Detecting Chiral Magnetic Effect by Lattice Dynamics

abstract:
  In the present paper, we propose that the chiral magnetic effect, the direct
consequence of the presence of Weyl points in the band structure, can be
detected by its coupling to certain phonon modes, which behave like pseudo
scalars under point group transformations. Such coupling can generate resonance
between intrinsic plasmon oscillation and the corresponding phonon modes,
leading to dramatic modification of the optical response by the external
magnetic field, which provides a new way to study chiral magnetic effect by
optical measurements.


title:
Cauchy and signaling problems for the time-fractional diffusion-wave
  equation

abstract:
  In this paper, some known and novel properties of the Cauchy and signaling
problems for the one-dimensional time-fractional diffusion-wave equation with
the Caputo fractional derivative of order $\beta,\ 1 \le \beta \le 2$ are
investigated. In particular, their response to a localized disturbance of the
initial data is studied. It is known that whereas the diffusion equation
describes a process where the disturbance spreads infinitely fast, the
propagation velocity of the disturbance is a constant for the wave equation. We
show that the time-fractional diffusion-wave equation interpolates between
these two different responses in the sense that the propagation velocities of
the maximum points, centers of gravity, and medians of the fundamental
solutions to both the Cauchy and the signaling problems are all finite. On the
other hand, the disturbance spreads infinitely fast and the time-fractional
diffusion-wave equation is non-relativistic like the classical diffusion
equation. In this paper, the maximum locations, the centers of gravity, and the
medians of the fundamental solution to the Cauchy and signaling problems and
their propagation velocities are described analytically and calculated
numerically. The obtained results for the Cauchy and the signaling problems are
interpreted and compared to each other.

categories: math.AP cond-mat.stat-mech math-ph math.CV math.MP


title:
Magnetic Moments of Baryons containing all heavy quarks in Quark-Diquark
  Model

abstract:
  The triply heavy flavour baryons are studied using the Quark-diquark
description of the three-body system. The confinement potential for present
study of triply heavy flavour baryons is assumed as coulomb plus power
potential with power index $\nu$. We have solved Schrodinger equation
numerically to calculate the masses of triply heavy flavour baryons. The masses
and magnetic moments of triply heavy flavour baryons are computed for different
power indices, $\nu$, starting from 0.4 to 1.0. The predicted masses and
magnetic moments are in good agreement with other theoretical predictions.


title: $\mathcal{PT}$-symmetric mode-locking

abstract:
  Parity-time ($\mathcal{PT}$) symmetry is one of the most important
accomplishments in optics over the past decade. Here the concept of
$\mathcal{PT}$ mode-locking of a laser is introduced, in which active phase
locking of cavity axial modes is realized by asymmetric mode coupling in a
complex time crystal. $\mathcal{PT}$ mode-locking shows a transition from
single to double pulse emission as the $\mathcal{PT}$ symmetry breaking point
is crossed. The transition can show a turbulent behavior, depending on a
dimensionless modulation parameter that plays the same role as the Reynolds
number in hydrodynamic flows.


title:
NMR Evidences for the coupling between conduction electrons and
  molecular degrees of freedom in the exotic member of the Bechgaard salt,
  (TMTSF)2FSO3

abstract:
  We performed Se and F-NMR measurements on single crystals of (TMTSF)2FSO3 to
characterize the electronic structures of different phases in the
Temperature-Pressure phase diagram, determined by precise transport
measurements [Jo et al., Phys. Rev. B67, 014516 (2003)]. We claim that such
varieties of electronic states in the refined phase diagram are caused by
strong couplings of the conduction electrons with FSO3 anions, especially with
the permanent electric dipoles on the anions. We suggest that as temperature
decreases, the FSO3 anions form orientational ordering through two steps; first
only the tetrahedrons form an orientational order leaving the orientations of
the electronic dipoles in random (transition I); then the dipoles form a
perfect orientational order at a lower temperature (transition II). In the
intermediate temperature range between transitions I and II, we found an
appreciable enhancement of homogeneous and inhomogeneous widths of 77Se-NMR
spectrum. From the analysis of the angular dependence of the linewidth, we
attributed these anomalies to the intramolecular charge disproportionation or
imbalance and its slow dynamics caused by the coupling with the permanent
electric dipole of anion. Results of 19F-NMR relaxation and lineshape
measurements support this picture very well. Electronic structures at higher
pressures up to 1.25 GPa are discussed on the basis of the results of the 77Se
and 19F-NMR measurements.


title:
Implementation of A Nanosecond Time-resolved APD Detector System for NRS
  Experiment in HEPS-TF

abstract:
  A nanosecond time-resolved APD detector system is implemented for Nuclear
Resonance Scattering (NRS) experiments in High Energy Photon Source-Test
Facility (HEPS-TF) project of China. The detector system consists of three
parts: the APD sensors, the fast preamplifiers and the TDC readout electronics.
To improve the reception solid angle and the quantum efficiency, the C30703FH
APDs (fabricated by Excelitas) are used as the sensors of the detectors. The
C30703FH has an effective light-sensitive area of 10X10 mm2 and an absorption
layer thickness of 110 {\mu}m. The fast preamplifier with gain of 59 dB and
bandwidth of 2 GHz is designed to readout the weak signal outputted by the
C30703FH APD. The detector system can work in single photon measurement mode
because the preamplifier increases the signal-to-noise ratio. Moreover, the TDC
is realized by FPGA multiphase method with a resolution bin of 1ns. The arrival
time of all scattering events between two start triggers can be recorded by the
FPGA TDC. In the X-ray energy of 14.4 keV, the time resolution (FWHM) of the
developed detector (APD sensor + fast amplifier) is 0.86 ns, and the whole
detector system (APD sensors + fast amplifiers + TDC readout electronics)
achieves a time resolution of 1.4 ns.


title: Achieving Zero-Error Capacity 1 for a Collision Channel Without Feedback

abstract:
  The collision channel without feedback (CCw/oFB) model introduced by Massey
and Mathys, depicts a scenario in which M users share a thermal noise-free
communication channel with random relative time offsets among their clocks.
This paper considers an extension of this model, which allows the receiver to
use successive interference cancellation (SIC) to iteratively cancel the
interference caused by those collided packets that have been decoded by the
receiver. As the main result of this paper, we derive the zero-error capacity
region of this channel in the slot-synchronous case, and present a zero-error
capacity achieving scheme by joint protocol sequences and channel coding
design. It is shown that the negative impact on the zero-error capacity due to
a lack of time synchronization can be removed by the help of SIC. Moreover, we
characterize the protocol sequences that can be used to achieve zero-error
capacity 1 [packets/slot] by proving new results on shift-invariant sequences
and throughput-invariant sequences; these sequences have been known to achieve
zero-error capacity for the basic CCw/oFB model without SIC. This
characterization sheds light on the minimum sequence period required in order
to attain zero-error capacity 1.


title: Narrowly distributed crystal orientation in biomineral vaterite

abstract:
  Biominerals formed by animals provide skeletal support, and many other
functions. They were previously shown to grow by aggregation of amorphous
nanoparticles, but never to grow ion-by-ion from solution, which is a common
growth mechanism for abiotic crystals. We analyze vaterite CaCO3 multi
crystalline spicules from the solitary tunicate Herdmania momus, with
Polarization dependent Imaging Contrast PIC mapping, scanning and aberration
corrected transmission electron microscopies. The first fully quantitative PIC
mapping data, presented here, measured 0{\deg} 30{\deg} angle spreads between
immediately adjacent crystals. Such narrowly distributed crystal orientations
demonstrate that crystallinity does not propagate from one crystal to another
0{\deg} angle spreads, nor that new crystals with random orientation 90{\deg}
nucleate. There are no organic layers at the interface between crystals, hence
a new, unknown growth mechanism must be invoked, with crystal nucleation
constrained within 30{\deg}. Two observations are consistent with crystal
growth from solution: vaterite microcrystals express crystal faces, and are
smooth at the nanoscale after cryo fracture. The observation of 30{\deg} angle
spreads, lack of interfacial organic layers, and smooth fracture figures
broadens the range of known biomineralization mechanisms and may inspire novel
synthetic crystal growth strategies. Spherulitic growth from solution is one
possible mechanism consistent with all these observations.


title: Self-consistent approach to many-body localization and subdiffusion

abstract:
  An analytical theory, based on the perturbative treatment of the disorder and
extended into a self-consistent set of equations for the dynamical density
correlations, is developed and applied to the prototype one-dimensional model
of many-body localization. Results show a qualitative agreement with
numerically obtained dynamical structure factor in the whole range of
frequencies and wavevectors, as well as across the transition to the nonergodic
behavior. The theory reveals the singular nature of the one-dimensional
problem, whereby on the ergodic side the dynamics is subdiffusive with
dynamical conductivity $\sigma(\omega) \propto |\omega|^\alpha$, i.e., with
vanishing d.c. limit $\sigma_0=0$ and $\alpha<1$ varying with disorder, while
we get $\alpha >1$ in the localized phase.


title: On the length of global integrals for $GL_n$

abstract:
  In this paper we prove Conjecture \ref{conj1} for a set of representations of
the group $GL_n({\bf A})$. This Conjecture is stated in complete generality as
Conjecture 1 in \cite{G2}, and here we prove it for various cases. See
Conjecture \ref{conj2} below. First we prove it in the case when the length of
the integral is four, and then we discuss the general case.


title: Sponge like nanoporous single crystals of gold

abstract:
  Single crystals in nature often demonstrate fascinating intricate porous
morphologies rather than classical faceted surfaces. We attempt to grow such
crystals, drawing inspiration from biogenic porous single crystals. Here we
show that nanoporous single crystals of gold can be grown with no need for any
elaborate fabrication steps. These crystals are found to grow following
solidification of a eutectic composition melt that forms as a result of the
dewetting of nanometric thin films. We also present a kinetic model that shows
how this nano-porous single-crystalline structure can be obtained, and which
allows the potential size of the porous single crystal to be predicted.
Retaining their single crystalline nature is due to the fact that the full
crystallization process is faster than the average period between two
subsequent nucleation events. Our findings clearly demonstrate that it is
possible to form singe crystalline nano porous metal crystals in a controlled
manner. INTRODUCTION


title: Exact correlations in a single file system with a driven tracer

abstract:
  We study the effect of a single driven tracer particle in a bath of other
particles performing the random average process on an infinite line using a
stochastic hydrodynamics approach. We consider arbitrary fixed as well as
random initial conditions and compute the two-point correlations. For quenched
uniform and annealed steady state initial conditions we show that in the large
time $T$ limit the fluctuations and the correlations of the positions of the
particles grow subdiffusively as $\sqrt{T}$ and have well defined scaling forms
under proper rescaling of the labels. We compute the corresponding scaling
functions exactly for these specific initial configurations and verify them
numerically. We also consider a non translationally invariant initial condition
with linearly increasing gaps where we show that the fluctuations and
correlations grow superdiffusively as $T^{3/2}$ at large times.


title: A Sequential Approach to the Henstock Integral

abstract:
  The theory of integration over R is rich with techniques as well as necessary
and sufficient conditions under which integration can be performed. Of the many
different types of integrals that have been developed since the days of Newton
and Leibniz, one relative newcomer is that of the Henstock integral, aka the
Henstock-Kurzweil integral, Generalized Riemann integral, or gauge integral,
which was discovered independently by Henstock and Kurzweil in the mid-1950s.
In this paper, we develop an alternative, sequential definition of the Henstock
integral over closed intervals in R that we denote as the Sequential Henstock
integral. We show its equivalence to the standard epsilon-delta definition of
the Henstock integral as well as to the Darboux definition and to a topological
definition of the Henstock integral. We then establish the basic properties and
fundamental theorems, including two convergence theorems, for the Sequential
Henstock integral and offer suggestions for further study.


title:
Order, disorder and tunable gaps in the spectrum of Andreev bound states
  in a multi-terminal superconducting device

abstract:
  We consider the spectrum of Andreev bound states (ABSs) in an exemplary
4-terminal superconducting structure where 4 chaotic cavities are connected by
QPCs to the terminals and to each other forming a ring. Such a tunable device
can be realized in 2DEG-superconductor structures.
  We concentrate on the limit of a short structure and large conductance of the
QPCs where a quasi-continuous spectrum is formed. The energies can be tuned by
the superconducting phases. We observe the opening and closing of gaps in the
spectrum. This concerns the usual proximity gap that separates the levels from
zero energy as well as less usual "smile" gaps that split the levels of the
spectrum.
  We demonstrate a remarkable crossover in the overall spectrum that occurs
upon changing the ratio of conductance of the inner and outer QPCs. At big
values of the ratio, the levels exhibit a generic behavior expected for the
spectrum of a disordered system manifesting level repulsion and "Brownian
motion" upon changing the phases. At small values of the ratio, the levels are
squeezed into narrow bunches separated by wide smile gaps. Each bunch consists
of almost degenerate ABSs.
  We study in detail the properties of the spectrum in the limit of a small
ratio, paying special attention to the crossings of bunches. We distinguish two
types of crossings: i. with a regular phase dependence of the levels and ii.
crossings where the Brownian motion of the levels leads to an apparently
irregular phase-dependence. We work out a perturbation theory to explain the
observations.
  The unusual properties of the spectrum originate from unobvious topological
effects. Topology of the first kind is related to the winding of the
semiclassical Green's function. It is responsible for the proximity gaps.
Topology of the second kind comes about the discreteness of the number of modes
and is responsible for the smile gaps.


title:
Measurement of horizontal air showers with the Auger Engineering Radio
  Array

abstract:
  The Auger Engineering Radio Array (AERA), at the Pierre Auger Observatory in
Argentina, measures the radio emission of extensive air showers in the 30-80
MHz frequency range. AERA consists of more than 150 antenna stations
distributed over 17 km$^2$. Together with the Auger surface detector, the
fluorescence detector and the under-ground muon detector (AMIGA), AERA is able
to measure cosmic rays with energies above 10$^{17}$ eV in a hybrid detection
mode. AERA is optimized for the detection of air showers up to 60$^{\circ}$
zenith angle, however, using the reconstruction of horizontal air showers with
the Auger surface array, very inclined showers can also be measured. In this
contribution an analysis of the AERA data in the zenith angle range from
62$^{\circ}$ to 80$^{\circ}$ will be presented. CoREAS simulations predict
radio emission footprints of several km$^2$ for horizontal air showers, which
are now confirmed by AERA measurements. This can lead to radio-based
composition measurements and energy determination of horizontal showers in the
future and the radio detection of neutrino induced showers is possible.


title: D-branes from Pure Spinor Superstring in AdS_5 x S^5 Background

abstract:
  We examine the surface term for the BRST transformation of the open pure
spinor superstring in an AdS_5 x S^5 background. We find that the boundary
condition to eliminate the surface term leads to a classification of possible
configurations of 1/2 supersymmetric D-branes.


title: A note on intersecting hypergraphs with large cover number

abstract:
  We give a construction of r-partite r-uniform intersecting hypergraphs with
cover number at least r-4 for all but finitely many r. This answers a question
of Abu-Khazneh, Barat, Pokrovskiy and Szabo, and shows that a long-standing
unsolved conjecture due to Ryser is close to being best possible for every
value of r.


title:
Algebraic disturbances and their consequences in rotating channel flow
  transition

abstract:
  It is now established that subcritical mechanisms play a crucial role in the
transition to turbulence of non-rotating plane shear flows. The role of these
mechanisms in rotating channel flow is examined here in the linear and
nonlinear stages. Distinct patterns of behaviour are found: the transient
growth leading to nonlinearity at low rotation rates $Ro$, a highly chaotic
intermediate $Ro$ regime, a localised weak chaos at higher $Ro$, and complete
stabilization of transient disturbances at very high $Ro$. At very low $Ro$,
the transient growth amplitudes are close to those for non-rotating flow, but
Coriolis forces already assert themselves by producing distinct asymmetry about
the channel centreline. Nonlinear processes are then triggered, in a
streak-breakdown mode of transition. The high $Ro$ regimes do not show these
signatures, here the leading eigenmode emerges as dominant in the early stages.
Elongated structures plastered close to one wall are seen at higher rotation
rates. Rotation is shown to reduce non-normality in the linear operator, in an
indirect manifestation of Taylor--Proudman effects. Although the critical
Reynolds for exponential growth of instabilities is known to vary a lot with
rotation rate, we show that the energy critical Reynolds number is insensitive
to rotation rate. It is hoped that these findings will motivate experimental
verification, and examination of other rotating flows in this light.


title: Jupiter internal structure: the effect of different equations of state

abstract:
  Heavy elements, even though its smaller constituent, are crucial to
understand Jupiter formation history. Interior models are used to determine the
amount of heavy elements in Jupiter interior, nevertheless this range is still
subject to degeneracies due to uncertainties in the equations of state. Prior
to Juno mission data arrival, we present Jupiter optimized calculations
exploring the effect of different model parameters in the determination of
Jupiter's core and heavy element's mass. We perform comparisons between
equations of state published recently. The interior model of Jupiter is
calculated from the equations of hydrostatic equilibrium, mass and energy
conservation, and energy transport. The mass of the core and heavy elements is
adjusted to match Jupiter's observational constrains radius and gravitational
moments. We show that the determination of Jupiter interior structure is tied
to the estimation of its gravitational moments and the accuracy of equations of
state of hydrogen, helium and heavy elements. The location of the region where
Helium rain occurs as well as its timescale are important to determine the
distribution of heavy elements and helium in the interior of Jupiter. We show
that differences find when modeling Jupiter's interior with recent EOS are more
likely due to differences in the internal energy and entropy calculation. The
consequent changes in the thermal profile lead to different estimations of the
mass of the core and heavy elements, explaining differences in recently
published Jupiter interior models. Our results help clarify differences find in
Jupiter interior models and will help the interpretation of upcoming Juno data.


title: Formation of Curved Micron-Sized Single Crystals

abstract:
  Crystals in nature often demonstrate curved morphologies rather than
classical faceted surfaces. Inspired by biogenic curved single crystals, we
demonstrate that gold single crystals exhibiting curved surfaces can be grown
with no need of any fabrication steps. These single crystals grow from the
confined volume of a droplet of a eutectic composition melt which forms via the
dewetting of nanometric thin films. We can control their curvature by
controlling the environment in which the process is carried out, including
several parameters, such as the contact angle and the curvature of the drops by
changing the surface tension of the liquid drop during crystal growth. Here we
present an energetic model that explains this phenomenon and predicts why and
under what conditions crystals will be forced to grow with the curvature of the
micro droplet even though the energetic state of a curved single crystal is
very high.


title:
Calcite single crystals as hosts for atomic-scale entrapment and slow
  release of drugs

abstract:
  This study presents a complete structural and biological characterization of
Doxorubicin CaCO3 single crystals as a pH responsive drug carrier. Using a
biomimetic approach, it was demonstrated that calcite single crystals are able,
during their growth in presence of doxorubicin, to entrap drug molecules inside
their lattice, along specific crystallographic directions. High resolution
synchrotron powder diffraction measurements allowed the determination of the
lattice distortion and microstructural parameters. Confocal microscopy
confirmed that doxorubicin is uniformly embedded in the crystal and that the
drug is not only adsorbed on the crystal surface. A slow release of DOX is
obtained that occurs preferentially in proximity of the crystals, targeting
cancer cells.


title:
Intracrystalline inclusions within single crystalline hosts: from
  biomineralization to bio-inspired crystal growth

abstract:
  Many crystals in nature exhibit fascinating mechanical, optical, magnetic and
other characteristics. One of the reasons for this phenomenon has to do with
the presence of specific organic molecules that are tightly associated with the
mineral. Over the years, some organic crystals have been found to be located
within the lattices of their singlecrystalline biogenic hosts. A number of
questions remain unanswered: for example, how do these molecules become
incorporated and what is their function? In this review we survey the gradual
refinement of the above mentioned finding in biogenic crystals, with the object
of tracing the acquisition of our fundamental knowledge in this field during
the last 50 years. We highlight the progress made in understanding the function
and significance of this intracrystalline organic matter, from the earliest
observations of this phenomenon in a biological system to the highly promising
recent achievements in bio-inspired material synthesis, where intracrystalline
molecules have been used in many studies to synthesize numerous synthetic
nanohybrid composites with fascinating new properties.


title: Hidden long-range order in a spin-orbit coupled two-dimensional Bose gas

abstract:
  A spin-orbit coupled two-dimensional (2D) Bose gas is shown to simultaneously
possess quasi and true long-range order in the total and relative phase
sectors, respectively. The total phase undergoes a Berenzinskii-
Kosterlitz-Thouless transition to a low temperature phase with quasi long-range
order, as expected for a two- dimensional quantum gas. Additionally, the
relative phase undergoes an Ising-type transition building up true long-range
order, which is induced by the anisotropic spin-orbit coupling. Based on the
Bogoliubov approach, expressions for the total- and relative-phase fluctuations
are derived analytically for the low temperature regime. Numerical simulations
of the stochastic projected Gross-Pitaevskii equation (SPGPE) give a good
agreement with the analytical predictions.


title: Temporal ghost imaging with pseudo-thermal speckle light

abstract:
  We report ghost imaging of a single non-reproducible temporal signal in the
range of tens kHz by using pseudo-thermal speckle light patterns and a single
detector array with a million of pixels working without any temporal
resolution. A set of speckle patterns is generated deterministically at
radio-frequency rate, multiplied by the temporal signal and time integrated in
a single shot by the camera. The temporal information is retrieved by computing
the spatial intensity correlations between this time integrated image and each
speckle pattern of the set.


title:
Beaming of helical light from plasmonic vortices via adiabatically
  tapered nanotip

abstract:
  We demonstrate the generation of far-field propagating optical beams with a
desired orbital angular momentum by using a smooth optical mode transformation
between a plasmonic vortex and free space Laguerre-Gaussian modes. This is
obtained by means of an adiabatically tapered gold tip surrounded by a spiral
slit. The proposed physical model, backed up by the numerical study, brings
about an optimized structure which is fabricated by using highly reproducible
secondary electron lithography technique. Optical measurements of the structure
excellently agree with the theoretically predicted far-field distributions.
This architecture provides a unique platform for a localized excitation of
plasmonic vortices followed by its beaming.


title: The KLOE-2 experiment at DAFNE

abstract:
  The KLOE-2 experiment at the INFN Laboratori Nazionali di Frascati (LNF) is
currently taking data at the upgraded $e^{+}e^{-}$ DAFNE collider. Present Run
II follows a~development phase to assess the feasibility of a long term
acquisition program, Run I, which successfully ended in July 2015 with 1
fb$^{-1}$ integrated luminosity collected in less than eight months. KLOE-2
represents the continuation of the KLOE experiment with a new physics program.
The KLOE detector has undergone several upgrades including state-of-the-art
cylindrical GEM Inner Tracker, electron-positron taggers for the
$\gamma\gamma$-physics studies and new calorimeters around the interaction
point. In this article we briefly present the overview of the KLOE-2 experiment
including the present status and achievements together with the physics plans.


title: Structural Analysis of Metal doped Calcium Oxalate

abstract:
  Calcium oxalate crystals are the most common biominerals found in plants.
They also make their presence known as painful kidney stones in humans and
animals. Their function in plants is extraordinarily versatile and encompasses
calcium storage and defense mechanisms against herbivores and detoxification
processes. Since plants containing calcium oxalate crystals are often exposed
to metallic environments, we studied the interaction of such environmental
metals with calcium oxalate in vitro. We showed that selected metals are indeed
incorporated into synthetic calcium oxalate, and in a manner that depends on
their ionic radius when precipitated in solution. One such mechanism of
incorporation is based on the replacement of calcium ions by other metal
cations within the host unit cell. The unit cell of calcium oxalate expands
when incorporating elements with larger atomic radii and shrinks when doped
with elements possessing ionic radii smaller than that of calcium. In this
systematic study, metal-doped calcium oxalate crystals were characterized by
means of high-resolution synchrotron X-ray powder diffraction,
energy-dispersive X-ray spectroscopy, inductively coupled plasma atomic
emission spectroscopy, and transmission electron microscopy. Better
understanding of metal incorporation into mineral hosts might lead to ways of
developing new and more efficient sorbent materials for detoxification
processes.


title:
Existence uniqueness for a class of Nonlinear Discrete Boundary Value
  Problems

abstract:
  A monotone iterative method is proposed to solve nonlinear discrete boundary
value problems with the support of upper and lower solutions. We establish some
new existence results. Under some sufficient conditions, we establish maximum
principle for linear discrete boundary value problem, which relies on Green's
function and its constant sign. We then use it to establish existence of unique
solution for the nonlinear discrete boundary value problem $\Delta^2 y(t-1)=
f(t, y(t)),~t\in[1, T]$, $y(0)=0,~y(T+1)=0$.


title: Realising Type II Weyl Points in an Optical Lattice

abstract:
  The recent discovery of the Lorentz symmetry-violating 'Type II' Weyl
semimetal phase has renewed interest in the study of Weyl physics in condensed
matter systems. However, tuning the exceptional properties of this novel state
has remained a challenge. Optical lattices, created using standing laser beams,
provide a convenient platform to tune tunnelling parameters continuously in
time. In this paper, we propose a generalised two level system exhibiting type
II Weyl points that can be realised using ultra-cold atoms in an optical
lattice. The system is engineered using a three-dimensional lattice with
complex $\pi$ phase tunnelling amplitudes. Various unique properties of the
type II Weyl semimetal such as open Fermi surface, anomalous chirality and
topological Fermi arcs can be probed using the proposed optical lattice scheme.


title: Connected Order Ideals and P-Partitions

abstract:
  Given a finite poset $P$, we associate a simple graph denoted by $G_P$ with
all connected order ideals of $P$ as vertices, and two vertices are adjacent if
and only if they have nonempty intersection and are incomparable with respect
to set inclusion. We establish a bijection between the set of maximum
independent sets of $G_P$ and the set of $P$-forests, introduced by F\'eray and
Reiner in their study of the fundamental generating function $F_P(\textbf{x})$
associated with $P$-partitions. Based on this bijection, in the cases when $P$
is naturally labeled we show that $F_P(\textbf{x})$ can factorise, such that
each factor is a summation of rational functions determined by maximum
independent sets of a connected component of $G_P$. This approach enables us to
give an alternative proof for F\'eray and Reiner's nice formula of
$F_P(\textbf{x})$ for the case of $P$ being a naturally labeled forest with
duplications. Another consequence of our result is a product formula to compute
the number of linear extensions of $P$.


title:
Frameworks for Solving Turing Kernel Lower Bound Problem and Finding
  Natural Candidate Problems in NP-intermediate

abstract:
  Kernelization is a significant topic in parameterized complexity. Turing
kernelization is a general form of kernelization. In the aspect of
kernelization, an impressive hardness theory has been established [Bodlaender
etc. (ICALP 2008, JCSS2009), Fortnow and Santhanam (STOC 2008, JCSS 2011), Dell
and van Melkebeek (STOC 2010, J. ACM 2014), Drucker (FOCS 2012, SIAM J. Comput.
2015)], which can obtain lower bounds of kernel size. Unfortunately, there is
yet no tool can prove Turing kernel lower bound for any FPT problem modulo any
reasonable complexity hypothesis. Thus, constructing a framework for Turing
kernel lower bound was proposed as an open problem in different occasions
[Fernau etc. (STACS 2009), Misra etc. (Discrete Optimization 2011), Kratsch
(Bulletin of the EATCS 2014), Cygan etc. (Dagstuhl Seminars on kernels 2014)].
Ladner [J. ACM 1975] proved that if $P \not = NP$, then there exist infinitely
many NP-intermediate problems. However, the NP-intermediate problem constructed
by Ladner is artificial. Thus, finding natural NP-intermediate problems under
the assumption of $P \not= NP$ is a longstanding open problem in computation
complexity community. This paper builds a new bridge between parameterized
complexity and classic computational complexity. By using this new connection,
some frameworks can be constructed. Based on the assumption that the polynomial
hierarchy and the exponential hierarchy will not collapse, these frameworks
have three main applications. Firstly, these frameworks can be used to obtain
Turing kernel lower bounds of some important FPT problems, thus solving the
first open problem. Secondly, these frameworks can also be used to obtain
better kernel lower bounds for these problems. Thirdly, these frameworks can be
used to figure out a large number of natural problems in NP-intermediate, thus
making some contributions to the second open problem.


title: SeqGAN: Sequence Generative Adversarial Nets with Policy Gradient

abstract:
  As a new way of training generative models, Generative Adversarial Nets (GAN)
that uses a discriminative model to guide the training of the generative model
has enjoyed considerable success in generating real-valued data. However, it
has limitations when the goal is for generating sequences of discrete tokens. A
major reason lies in that the discrete outputs from the generative model make
it difficult to pass the gradient update from the discriminative model to the
generative model. Also, the discriminative model can only assess a complete
sequence, while for a partially generated sequence, it is non-trivial to
balance its current score and the future one once the entire sequence has been
generated. In this paper, we propose a sequence generation framework, called
SeqGAN, to solve the problems. Modeling the data generator as a stochastic
policy in reinforcement learning (RL), SeqGAN bypasses the generator
differentiation problem by directly performing gradient policy update. The RL
reward signal comes from the GAN discriminator judged on a complete sequence,
and is passed back to the intermediate state-action steps using Monte Carlo
search. Extensive experiments on synthetic data and real-world tasks
demonstrate significant improvements over strong baselines.


title: Intrinsic Proton NMR Studies of Mg(OH)$_2$ and Ca(OH)$_2$

abstract:
  We studied the short proton free induction decay signals and the broad ^1H
NMR spectra of Mg(OH)2 and Ca(OH)2 powders at 77-355 K and 42 MHz using pulsed
NMR techniques. Using a Gaussian-type back extrapolation procedure for the
obscured data of the proton free induction decay signals, we obtained more
precise values of the second moments of the Fourier-transformed broad NMR
spectra than those in a previous report [Y. Itoh and M. Isobe, J. Phys. Soc.
Jpn. Vol. 84, 113601 (2015)] and compared with the theoretical second moments.
The decrease in the second moment could not account for the large decrease in
the magnitude of the intrinsic proton spin-lattice relaxation rate 1/T_1 from
Mg(OH)2 to Ca(OH)2. The analysis of 1/T_1 $propto$ exp(-E_g/k_BT) with E_g~0.01
eV points to a local hopping mechanism, and that of 1/T_1 $propto$ T^n with
n~0.5 points to an anharmonic rattling mechanism.


title: Replica Analysis for the Duality of the Portfolio Optimization Problem

abstract:
  In the present paper, the primal-dual problem consisting of the investment
risk minimization problem and the expected return maximization problem in the
mean-variance model is discussed using replica analysis. As a natural extension
of the investment risk minimization problem under only a budget constraint that
we analyzed in a previous study, we herein consider a primal-dual problem in
which the investment risk minimization problem with budget and expected return
constraints is regarded as the primal problem, and the expected return
maximization problem with budget and investment risk constraints is regarded as
the dual problem. With respect to these optimal problems, we analyze a quenched
disordered system involving both of these optimization problems using the
approach developed in statistical mechanical informatics, and confirm that both
optimal portfolios can possess the primal-dual structure. Finally, the results
of numerical simulations are shown to validate the effectiveness of the
proposed method.

categories: q-fin.PM cond-mat.dis-nn math.OC stat.AP


title:
Cosmological constraints from the redshift dependence of the
  Alcock-Paczynski effect: application to the SDSS-III BOSS DR12 galaxies

abstract:
  We apply the methodology developed in \cite{Li2014,Li2015} to BOSS DR12
galaxies and derive cosmological constraints from the redshift dependence of
the Alcock-Paczynski (AP) effect. The apparent anisotropy in the distribution
of observed galaxies arise from two main sources, the redshift-space distortion
(RSD) effect due to the galaxy peculiar velocities, and the geometric
distortion when incorrect cosmological models are assumed for transforming
redshift to comoving distance, known as the AP effect. Anisotropies produced by
the RSD effect are, although large, maintaining a nearly uniform magnitude over
a large range of redshift, while the degree of anisotropies from the AP effect
varies with redshift by much larger magnitude. We split the DR12 galaxies into
six redshift bins, measure the 2-point correlation function in each bin, and
assess the redshift evolution of anisotropies. We obtain constraints of
$\Omega_m=0.290 \pm 0.053,\ \ w = -1.07 \pm 0.15$, which are comparable with
the current constraints from other cosmological probes such as type Ia
supernovae, cosmic microwave background, and baryon acoustic oscillation (BAO).
Combining these cosmological probes with our method yield tight constraints of
$ \Omega_m = 0.301 \pm 0.006,\ w=-1.054 \pm 0.025$. Our method is complementary
to the other large scale structure probes like BAO and topology. We expect this
technique will play an important role in deriving cosmological constraints from
large scale structure surveys.


title:
A spiral galaxy's mass distribution uncovered through lensing and
  dynamics

abstract:
  We investigate the matter distribution of a spiral galaxy with a
counter-rotating stellar core, SDSS J1331+3628 (J1331), independently with
gravitational lensing and stellar dynamical modelling. By fitting a
gravitational potential model to a quadruplet of lensing images around J1331's
bulge, we tightly constrain the mass inside the Einstein radius R_ein = (0.91
+/- 0.02)'' (~= 1.83 +/- 0.04 kpc) to within 4%: M_ein = (7.8 +/- 0.3) x 10^10
M_Sun. We model observed long-slit major axis stellar kinematics in J1331's
central regions by finding Multi-Gaussian Expansion (MGE) models for the
stellar and dark matter distribution that solve the axisymmetric Jeans
equations. The lens and dynamical model are independently derived, but in very
good agreement with each other around ~R_ein. We find that J1331's center
requires a steep total mass-to-light ratio gradient. A dynamical model
including an NFW halo (with virial velocity v_200 ~= 240 +/- 40 km/s and
concentration c_200 ~= 8 +/- 2) and moderate tangential velocity anisotropy
(beta_z ~= -0.4 +/- 0.1) can reproduce the signatures of J1331's
counter-rotating core and predict the stellar and gas rotation curve at larger
radii. However, our models do not agree with the observed velocity dispersion
at large radii. We speculate that the reason could be a non-trivial change in
structure and kinematics due to a possible merger event in J1331's recent past.


title:
MILES extended: Stellar population synthesis models from the optical to
  the infrared

abstract:
  We present the first single-burst stellar population models which covers the
optical and the infrared wavelength range between 3500 and 50000 Angstrom and
which are exclusively based on empirical stellar spectra. To obtain these joint
models, we combined the extended MILES models in the optical with our new
infrared models that are based on the IRTF (Infrared Telescope Facility)
library. The latter are available only for a limited range in terms of both age
and metallicity. Our combined single-burst stellar population models were
calculated for ages larger than 1 Gyr, for metallicities between [Fe/H] = -0.40
and 0.26, for initial mass functions of various types and slopes, and on the
basis of two different sets of isochrones. They are available to the scientific
community on the MILES web page. We checked the internal consistency of our
models and compared their colour predictions to those of other models that are
available in the literature. Optical and near infrared colours that are
measured from our models are found to reproduce the colours well that were
observed for various samples of early-type galaxies. Our models will enable a
detailed analysis of the stellar populations of observed galaxies.


title:
Lp and almost sure rates of convergence of averaged stochastic gradient
  algorithms: locally strongly convex objective

abstract:
  An usual problem in statistics consists in estimating the minimizer of a
convex function. When we have to deal with large samples taking values in high
dimensional spaces, stochastic gradient algorithms and their averaged versions
are efficient candidates. Indeed, (1) they do not need too much computational
efforts, (2) they do not need to store all the data, which is crucial when we
deal with big data, (3) they allow to simply update the estimates, which is
important when data arrive sequentially. The aim of this work is to give
asymptotic and non asymptotic rates of convergence of stochastic gradient
estimates as well as of their averaged versions when the function we would like
to minimize is only locally strongly convex.


title: Topological Hall and Spin Hall Effects in Disordered Skyrmionic Textures

abstract:
  We carry out a throughout study of the topological Hall and topological spin
Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall
angles are evaluated across the energy band structure in the multiprobe
Landauer-B\"uttiker formalism and their link to the effective magnetic field
emerging from the real space topology of the spin texture is highlighted. We
discuss these results for an optimal skyrmion size and for various sizes of the
sample and found that the adiabatic approximation still holds for large
skyrmions as well as for few atomic size-nanoskyrmions. Finally, we test the
robustness of the topological signals against disorder strength and show that
topological Hall effect is highly sensitive to momentum scattering.


title:
Collective dynamics and entanglement of two atoms embedded into negative
  index material

abstract:
  We study the dynamics of two two-level atoms embedded near to the interface
of paired meta-material slabs, one of negative permeability and the other of
negative permittivity. The interface behaves as a plasmonic waveguide composed
of surface-plasmon polariton modes. It is found that significantly different
dynamics occur for the resonant and an off-resonant couplings of the plasma
field to the atoms. In the case of the resonant coupling, the plasma field does
not appear as a dissipative reservoir to the atoms. We adopt the image method
and show that the dynamics of the two atoms are completely equivalent to those
of a four-atom system. Moreover, two threshold coupling strengths exist, one
corresponding to the strength of coupling of the plasma field to the symmetric
and the other the antisymmetric mode of the two-atom system. The thresholds
distinguish between the non-Markovian (memory preserving) and Markovian
(memoryless) regimes of the evolutions that different time scales of the
evolution of the memory effects and entanglement can be observed. The Markovian
regime is characterized by exponentially decaying whereas the non-Markovian
regime by sinusoidally oscillating contributions to the evolution of the
probability amplitudes. The solutions predict a large and long living
entanglement mediated by the plasma field in both Markovian and non-Markovian
regimes of the evolution. We also show that a simultaneous Markovian and
non-Markovian regime of the evolution may occur in which the memory effects
exist over a finite evolution time. In the case of an off-resonant coupling of
the atoms to the plasma field, the atoms interact with each other by exchanging
virtual photons which results in the dynamics corresponding to those of two
atoms coupled to a common reservoir. In addition, the entanglement is
significantly enhanced under the off-resonant coupling.


title: Quasicontinuous functions with values in Piotrowski spaces

abstract:
  A topological space $X$ is called Piotrowski if every quasicontinuous map
$f:Z\to X$ from a Baire space $Z$ to $X$ has a continuity point. In this paper
we survey known results on Piotrowski spaces and investigate the relation of
Piotrowski spaces to strictly fragmentable, Stegall, and game determined
spaces. Also we prove that a Piotrowski Tychonoff space $X$ contains a dense
(completely) metrizable Baire subspace if and only if $X$ is Baire (Choquet).


title:
Set-Point Regulation of Linear Continuous-Time Systems using
  Neuromorphic Vision Sensors

abstract:
  Recently developed neuromorphic vision sensors have become promising
candidates for agile and autonomous robotic applications primarily due to, in
particular, their high temporal resolution and low latency. Each pixel of this
sensor independently fires an asynchronous stream of "retinal events" once a
change in the light field is detected. Existing computer vision algorithms can
only process periodic frames and so a new class of algorithms needs to be
developed that can efficiently process these events for control tasks. In this
paper, we investigate the problem of regulating a continuous-time linear time
invariant (LTI) system to a desired point using measurements from a
neuromorphic sensor. We present an $H_\infty$ controller that regulates the LTI
system to a desired set-point and provide the set of neuromorphic sensor based
cameras for the given system that fulfill the regulation task. The
effectiveness of our approach is illustrated on an unstable system.


title: Enumeration of points, lines, planes, etc

abstract:
  One of the earliest results in enumerative combinatorial geometry is the
following theorem of de Bruijn and Erd\H{o}s: Every set of points $E$ in a
projective plane determines at least $|E|$ lines, unless all the points are
contained in a line. Motzkin and others extended the result to higher
dimensions, who showed that every set of points $E$ in a projective space
determines at least $|E|$ hyperplanes, unless all the points are contained in a
hyperplane. Let $E$ be a spanning subset of a $d$-dimensional vector space. We
show that, in the partially ordered set of subspaces spanned by subsets of $E$,
there are at least as many $(d-k)$-dimensional subspaces as there are
$k$-dimensional subspaces, for every $k$ at most $d/2$. This confirms the
"top-heavy" conjecture of Dowling and Wilson for all matroids realizable over
some field. The proof relies on the decomposition theorem package for
$\ell$-adic intersection complexes.


title: A Multi-Technique Study of $CO_2$ Adsorption on $Fe_3$$O_4$ Magnetite

abstract:
  The adsorption of $CO_2$ on the $Fe_3$$O_4$(001)-($\sqrt{2}$ $\times$
$\sqrt{2}$)R45{\deg} surface was studied experimentally using temperature
programmed desorption (TPD), electron spectroscopies (UPS and XPS), and
scanning tunneling microscopy (STM). $CO_2$ binds most strongly at defects
related to Fe2+ including antiphase domain boundaries in the surface
reconstruction and above incorporated Fe interstitials. On the pristine
surface, $CO_2$ adsorbs molecularly at fivefold-coordinated Fe3+ sites with a
binding energy of 0.4 eV. Above a coverage of 4 molecules per ($\sqrt{2}$
$\times$ $\sqrt{2}$)R45{\deg} unit cell, further adsorption results in a
compression of the first monolayer up to a density approaching that of a $CO_2$
ice layer. Surprisingly, desorption of the second monolayer occurs at a lower
temperature ($\approx$ 84 K) than $CO_2$ multilayers ($\approx$ 88 K),
suggestive of a metastable phase or diffusion-limited island growth. The paper
also discusses design considerations for a vacuum system optimized to study the
surface chemistry of metal oxide single crystals, including the calibration and
characterisation of a molecular beam source for quantitative TPD measurements.


title: Probabilistic Feature Selection and Classification Vector Machine

abstract:
  Sparse Bayesian learning is a state-of-the-art supervised learning algorithm
that can choose a subset of relevant samples from the input data and make
reliable probabilistic predictions. However, in the presence of
high-dimensional data with irrelevant features, traditional sparse Bayesian
classifiers suffer from performance degradation and low efficiency by failing
to eliminate irrelevant features. To tackle this problem, we propose a novel
sparse Bayesian embedded feature selection method that adopts truncated
Gaussian distributions as both sample and feature priors. The proposed method,
called probabilistic feature selection and classification vector machine
(PFCVMLP ), is able to simultaneously select relevant features and samples for
classification tasks. In order to derive the analytical solutions, Laplace
approximation is applied to compute approximate posteriors and marginal
likelihoods. Finally, parameters and hyperparameters are optimized by the
type-II maximum likelihood method. Experiments on three datasets validate the
performance of PFCVMLP along two dimensions: classification performance and
effectiveness for feature selection. Finally, we analyze the generalization
performance and derive a generalization error bound for PFCVMLP . By tightening
the bound, the importance of feature selection is demonstrated.


title: Uniqueness of closed self-similar solutions to the Gauss curvature flow

abstract:
  We show the uniqueness of strictly convex closed smooth self-similar
solutions to the $\alpha$-Gauss curvature flow with $(1/n) < \alpha < 1+(1/n)$.
We introduce a Pogorelov type computation, and then we apply the strong maximum
principle. Our work combined with earlier works on the Gauss Curvature flow
imply that the $\alpha$-Gauss curvature flow with $(1/n) < \alpha < 1+(1/n)$
shrinks a strictly convex closed smooth hypersurface to a round sphere.


title: Leonard triples of $q$-Racah type

abstract:
  Let $\mathbb F$ denote a field, and let $V$ denote a vector space over
$\mathbb F$ with finite positive dimension. Pick a nonzero $q \in \mathbb F$
such that $q^4 \not=1$, and let $A,B,C$ denote a Leonard triple on $V$ that has
$q$-Racah type. We show that there exist invertible $W, W', W'' $ in ${\rm
End}(V)$ such that (i) $A$ commutes with $W$ and $W^{-1}BW-C$; (ii) $B$
commutes with $W'$ and $(W')^{-1}CW'-A$; (iii) $C$ commutes with $W''$ and
$(W'')^{-1}AW''-B$. Moreover each of $W,W', W''$ is unique up to multiplication
by a nonzero scalar in $\mathbb F$. We show that the three elements $W'W,
W''W', WW''$ mutually commute, and their product is a scalar multiple of the
identity. A number of related results are obtained.


title:
Exotic Multi-fold Vortex Lattices of Spin-Orbit Coupled Bose-Einstein
  Condensates in Optical Lattices

abstract:
  We investigate the ground state of two-dimensional Bose-Einstein condensates
with Rashba spin-orbit coupling in square optical lattices and demonstrate the
existence of rich phases with different lattice structures, which is closely
related to the degenerate structure of single particle energy spectrum induced
by the competition of spin-orbit coupling and optical lattices. We find that
the ground state is in the phase with either parity-time-reversal or parity
symmetry by direct numerical simulation. We show the phase diagram of ground
state in the whole regime of spin-orbit coupling strength, and particularly
find that the system supports multi-fold vortex lattices, in which ground state
holds half-quantum vortex lattices, vortex-antivortex pair lattices and
fundamental vortex lattices, simultaneously, when single particle energy
minimums touch the boundary of the first Brillouin zone.


title: Efficient Integer Coefficient Search for Compute-and-Forward

abstract:
  Integer coefficient selection is an important decoding step in the
implementation of compute-and-forward (C-F) relaying scheme. Choosing the
optimal integer coefficients in C-F has been shown to be a shortest vector
problem (SVP) which is known to be NP hard in its general form. Exhaustive
search of the integer coefficients is only feasible in complexity for small
number of users while approximation algorithms such as Lenstra-Lenstra-Lovasz
(LLL) lattice reduction algorithm only find a vector within an exponential
factor of the shortest vector. An optimal deterministic algorithm was proposed
for C-F by Sahraei and Gastpar specifically for the real valued channel case.
In this paper, we adapt their idea to the complex valued channel and propose an
efficient search algorithm to find the optimal integer coefficient vectors over
the ring of Gaussian integers and the ring of Eisenstein integers. A second
algorithm is then proposed that generalises our search algorithm to the
Integer-Forcing MIMO C-F receiver. Performance and efficiency of the proposed
algorithms are evaluated through simulations and theoretical analysis.


title: Optomechanical Force Sensor in non-Markovian Regime

abstract:
  The optomechanical force sensor in non-Markovian environment for a mechanical
oscillator is presented. By performing homodyne detection we obtain an
generally expression for the output signal. It is shown that the weak force
detection is sensitive to the non-Markovian environment. The additional noise
can be obviously reduced comparing to the Markovian condition. Moreover, the
optimal additional noise can be maintained in a rather low level without using
assistant system or squeezing under available experimental condition in
unsolved sideband regime. Our results provides a promising platform for
reducing the additional noise by using engineered non-Markovian reservoir in
ultrasensitive detection.


title:
A first view with GAIA on KIC 8462852 - distance estimates and a
  comparison to other F stars

abstract:
  Distance estimates from Gaia parallax and expected luminosities are compared
for KIC 8462852. Gaia DR1 yields a parallax of $2.55\pm0.31$mas, that is a
distance of $391.4\substack{+53.6 \\ -42.0}$pc, or $391.4\substack{+122.1 \\
-75.2}$pc including systematic uncertainty. The distance estimate based on the
absolute magnitude of an F3V star and measured reddening is $\sim454\pm35$pc.
Both estimates agree within $<1\sigma$, which only excludes some of the most
extreme theorized scenarios for KIC 8462852. Future Gaia data releases will
determine the distance to within 1% and thus allow for the determination a
precise absolute luminosity.


title: Rationality in map and hypermap enumeration by genus

abstract:
  Generating functions for a fixed genus map and hypermap enumeration become
rational after a simple explicit change of variables. Their numerators are
polynomials with integer coefficients that obey a differential recursion, and
denominators are products of powers of explicit linear functions.


title:
Representation theory of the cyclotomic Cherednik algebra via the
  Dunkl-Opdam subalgebra

abstract:
  We give an alternate presentation of the cyclotomic rational Cherednik
algebra, which has the useful feature of compatibility with the Opdam-Dunkl
subalgebra. This presentation has a diagrammatic flavor, and it provides a
simple explanation of several surprising facts about this algebra. It allows
direct proof of the connection of category $\mathcal{O}$ to weighted KLR
algebras, allows us to classify the simple Dunkl-Opdam modules over the
Cherednik algebra and provides an algebraic construction of the KZ functor.
Furthermore, one of prime motivations for considering this approach is to
provide a better framework for connecting Cherednik algebras to Coulomb
branches of 3-d gauge theories.


title:
Predictions on the alpha decay chains of superheavy nuclei with Z =121
  within the range 290 $\leq$ A $\leq$ 339

abstract:
  A systematic study on the alpha decay half lives of various isotopes of
superheavy element \textit{Z} = 121 within the range 290 $\leq$ A $\leq$ 339 is
presented for the first time using Coulomb and proximity potential model for
deformed nuclei (CPPMDN). The calculated $\alpha$ decay half lives of the
isotopes within our formalism match well with the values computed using
Viola-Seaborg systematic, Universal curve of Poenaru et al., and the analytical
formula of Royer. In our study by comparing the $\alpha$ decay half lives with
the spontaneous fission half lives, we have predicted $2\alpha$ chain from
$^{309, 311, 312}$121, $3\alpha$ chain from $^{310}$121 and $1\alpha$ chain
from $^{313, 314}$121. Clearly our study shows that the isotopes of superheavy
element \textit{Z} = 121 within the mass range 309 $\leq$ A $\leq$ 314 will
survive fission and can be synthesized and detected in the laboratory via alpha
decay. We hope that our predictions will provide a new guide to future
experiments.


title: On two-quotient strong starters for $\mathbb{F}_q$

abstract:
  Let $G$ be a finite additive abelian group of odd order $n$, and let
$G^*=G\setminus\{0\}$ be the set of non-zero elements. A starter for $G$ is a
set $S=\{\{x_i,y_i\}:i=1,\ldots,\frac{n-1}{2}\}$ such that
$\{x_1,\ldots,x_\frac{n-1}{2},y_1,\ldots,y_\frac{n-1}{2}\}=G^*$ and
$\{\pm(x_i-y_i):i=1,\ldots,\frac{n-1}{2}\}=G^*$. Moreover, if
$\left|\left\{x_i+y_i:i=1,\ldots,\frac{n-1}{2}\right\}\right|=\frac{n-1}{2}$,
then $S$ is called a strong starter for $G$. A starter $S$ for $G$ is a $k$
quotient starter if there exists $Q\subseteq G^*$ of cardinality $k$ such that
$y_i/x_i\in Q$ or $x_i/y_i\in Q$, for $i=1,\ldots,\frac{n-1}{2}$. In this
paper, we give examples of two-quotient strong starters for $\mathbb{F}_q$,
where $q=2^kt+1$ is a prime power with $k>1$ a positive integer and $t$ an odd
integer greater than 1.


title:
Cross-Spectrum PM Noise Measurements, Thermal Energy and Metamaterial
  Filters

abstract:
  Virtually all commercial instruments for the measurement of the oscillator PM
noise make use of the Cross Spectrum method (arXiv:1004.5539 [physics.ins-det],
2010). High sensitivity is achieved by correlation and averaging on two equal
channels which measure the same input, and reject the background of the
instrument. We show that a systematic error is always present if the thermal
energy of the input power splitter is not accounted for. Such error can result
in noise under estimation up to a few dB in the lowest-noise quartz
oscillators, and in a complete nonsense in the case of cryogenic oscillators.
As another alarming fact, the presence of metamaterial components in the
oscillator results in unpredictable behavior and large errors, even in well
controlled experimental conditions. We observed a spread of 40 dB in the phase
noise spectra of an oscillator, just replacing the output filter.


title:
Feasibility of observing the {\alpha} decay chains from isotopes of SHN
  with Z = 128, Z = 126, Z = 124 and Z = 122

abstract:
  Taking the Coulomb and proximity potential model for deformed nuclei (CPPMDN)
as the interacting potential for the post-scission region, the alpha decay
properties of 34 isotopes of the superheavy nuclei with Z = 128 within the
range 306 $\leq$ A $\leq$ 339 have been studied, considering both the parent
and daughter nuclei to be deformed. The manuscript also deals with the decay
properties of the isotopes of Z = 126 (within 288 $\leq$ A $\leq$ 339), Z = 124
(within 284 $\leq$A $\leq$ 339) and Z = 122 (within 280 $\leq$ A $\leq$ 339).
The alpha decay half lives thus evaluated has been compared with the values
evaluated using other theoretical models and it was seen that, our theoretical
alpha decay half lives matches well with these values. Through the present
study, we have underlined and have established the fact that, among the 192
isotopes considered in the present study, only those isotopes
$^{321-324,328-335}$128, $^{318-320,323-327}$126, $^{305-308,315-322}$124 and
$^{298-307,311-314}$122 can be synthesized and detected through alpha decay in
laboratory. As the alpha decay half lives of these superheavy isotopes lie
within the experimental limits, we hope these predictions, on the decay modes
of these unknown nuclei, to pave the way for the future experiments. The proton
separation energy calculations on $^{306-339}$128, $^{288-336}$126,
$^{284-339}$124 and $^{280-339}$122 superheavy nuclei have also been done and
the study revealed the probable proton emitters among these nuclei.


title:
Incipient Berezinskii-Kosterlitz-Thouless transition in two-dimensional
  coplanar Josephson junctions

abstract:
  Superconducting hybrid junctions are revealing a variety of novel effects.
Some of them are due to the special layout of these devices, which often use a
coplanar configuration with relatively large barrier channels and the
possibility of hosting Pearl vortices. A Josephson junction with a quasi ideal
two-dimensional barrier has been realized by growing graphene on SiC with Al
electrodes. Chemical Vapor Deposition offers centimeter size monolayer areas
where it is possible to realize a comparative analysis of different devices
with nominally the same barrier. In samples with a graphene gap below 400 nm,
we have found evidence of Josephson coherence in presence of an incipient
Berezinskii-Kosterlitz-Thouless transition. When the magnetic field is cycled,
a remarkable hysteretic collapse and revival of the Josephson supercurrent
occurs. Similar hysteresis are found in granular systems and are usually
justified within the Bean Critical State model (CSM). We show that the CSM,
with appropriate account for the low dimensional geometry, can partly explain
the odd features measured in these junctions.


title:
On Selberg's Eigenvalue Conjecture for moduli spaces of abelian
  differentials

abstract:
  J.-C. Yoccoz proposed a natural extension of Selberg's Eigenvalue Conjecture
to moduli spaces of abelian differentials. We prove an approximation to this
conjecture. This gives a qualitative generalization of Selberg's $\frac{3}{16}$
Theorem to moduli spaces of abelian differentials on surfaces of genus $\geq
2$.


title: Quantum evolution in the stroboscopic limit of repeated measurements

abstract:
  We consider a quantum system dynamics caused by successive selective and
non-selective measurements of the probe coupled to the system. For the finite
measurement rate $\tau^{-1}$ and the system-probe interaction strength $\gamma$
we derive analytical evolution equations in the stroboscopic limit $\tau
\rightarrow 0$ and $\gamma^2 \tau = {\rm const}$, which can be considered as a
deviation from the Zeno subspace dynamics on a longer timescale $T \sim
(\gamma^2 \tau)^{-1} \gg \gamma^{-1}$. Non-linear quantum dynamics is analyzed
for selective stroboscopic projective measurements of an arbitrary rank.
Non-selective measurements are shown to induce the semigroup dynamics of the
system-probe aggregate. Both non-linear and decoherent effects become
significant at the timescale $T \sim (\gamma^2 \tau)^{-1}$, which is
illustrated by a number of examples.


title: Inverse Problems with Invariant Multiscale Statistics

abstract:
  We propose a new approach to linear ill-posed inverse problems. Our algorithm
alternates between enforcing two constraints: the measurements and the
statistical correlation structure in some transformed space. We use a
non-linear multiscale scattering transform which discards the phase and thus
exposes strong spectral correlations otherwise hidden beneath the phase
fluctuations. As a result, both constraints may be put into effect by linear
projections in their respective spaces. We apply the algorithm to
super-resolution and tomography and show that it outperforms ad hoc convex
regularizers and stably recovers the missing spectrum.


title:
Genetic Algorithm-based Mapper to Support Multiple Concurrent Users on
  Wireless Testbeds

abstract:
  Communication and networking research introduces new protocols and standards
with an increasing number of researchers relying on real experiments rather
than simulations to evaluate the performance of their new protocols. A number
of testbeds are currently available for this purpose and a growing number of
users are requesting access to those testbeds. This motivates the need for
better utilization of the testbeds by allowing concurrent experimentations. In
this work, we introduce a novel mapping algorithm that aims to maximize
wireless testbed utilization using frequency slicing of the spectrum resources.
The mapper employs genetic algorithm to find the best combination of requests
that can be served concurrently, after getting all possible mappings of each
request via an induced sub-graph isomorphism stage. The proposed mapper is
tested on grid testbeds and randomly generated topologies. The solution of our
mapper is compared to the optimal one, obtained through a brute-force search,
and was able to serve the same number of requests in 82.96% of testing
scenarios. Furthermore, we show the effect of the careful design of testbed
topology on enhancing the testbed utilization by applying our mapper on a
carefully positioned 8-nodes testbed. In addition, our proposed approach for
testbed slicing and requests mapping has shown an improved performance in terms
of total served requests, about five folds, compared to the simple allocation
policy with no slicing.


title: Indistinguishability

abstract:
  This is a systematic review of the concept of indistinguishability in both
classical and quantum mechanics, with particular attention to Gibbs' paradox.
Section 1 is on the Gibbs paradox; section 2 is a defense of the concept of
classical indistinguishability, that addresses (and refutes) the view that
classical particles can always be distinguished by their trajectories so are
distinguishable. Section 3 is on the notion of object more generally, and on
whether indistinguishables should be thought of as objects at all


title: A comparison of boundary correction methods for Strang splitting

abstract:
  In this paper we consider splitting methods in the presence of
non-homogeneous boundary conditions. In particular, we consider the corrections
that have been described and analyzed in Einkemmer, Ostermann 2015 and
Alonso-Mallo, Cano, Reguera 2016. The latter method is extended to the
non-linear case, and a rigorous convergence analysis is provided. We perform
numerical simulations for diffusion-reaction, advection-reaction, and
dispersion-reaction equations in order to evaluate the relative performance of
these two corrections. Furthermore, we introduce an extension of both methods
to obtain order three locally and evaluate under what circumstances this is
beneficial.


title: Experimental results on chiral magnetic and vortical effects

abstract:
  Various novel transport phenomena in chiral systems result from the interplay
of quantum anomalies with magnetic field and vorticity in high-energy heavy-ion
collisions, and could survive the expansion of the fireball and be detected in
experiments. Among them are the chiral magnetic effect, the chiral vortical
effect and the chiral magnetic wave, the experimental searches for which have
aroused extensive interest. The goal of this review is to describe the current
status of experimental studies at Relativistic Heavy Ion Collider at BNL and
the Large Hadron Collider at CERN, and to outline the future work in experiment
needed to eliminate the existing uncertainties in the interpretation of the
data.


title: Computability Theory of Closed Timelike Curves

abstract:
  We ask, and answer, the question of what's computable by Turing machines
equipped with time travel into the past: that is, closed timelike curves or
CTCs (with no bound on their size). We focus on a model for CTCs due to
Deutsch, which imposes a probabilistic consistency condition to avoid
grandfather paradoxes. Our main result is that computers with CTCs can solve
exactly the problems that are Turing-reducible to the halting problem, and that
this is true whether we consider classical or quantum computers. Previous work,
by Aaronson and Watrous, studied CTC computers with a polynomial size
restriction, and showed that they solve exactly the problems in PSPACE, again
in both the classical and quantum cases.
  Compared to the complexity setting, the main novelty of the computability
setting is that not all CTCs have fixed-points, even probabilistically. Despite
this, we show that the CTCs that do have fixed-points suffice to solve the
halting problem, by considering fixed-point distributions involving infinite
geometric series. The tricky part is to show that even quantum computers with
CTCs can be simulated using a Halt oracle. For that, we need the Riesz
representation theorem from functional analysis, among other tools.
  We also study an alternative model of CTCs, due to Lloyd et al., which uses
postselection to "simulate" a consistency condition, and which yields BPP_path
in the classical case or PP in the quantum case when subject to a polynomial
size restriction. With no size limit, we show that postselected CTCs yield only
the computable languages if we impose a certain finiteness condition, or all
languages nonadaptively reducible to the halting problem if we don't.


title:
Electron effective mass and mobility limits in degenerate perovskite
  stannate BaSnO$_3$

abstract:
  The high room temperature mobility and the electron effective mass in
BaSnO$_3$ are investigated in depth by evaluation of the free carrier
absorption observed in infrared spectra for epitaxial films with free electron
concentrations from $8.3 \times 10^{18}$ to $7.3 \times 10^{20}$~cm$^{-3}$.
Both the optical band gap widening by conduction band filling and the carrier
scattering mechanisms in the low and high doping regimes are consistently
described employing parameters solely based on the intrinsic physical
properties of BaSnO$_3$. The results explain the current mobility limits in
epitaxial films and demonstrate the potential of BaSnO$_3$ to outperform
established wide band gap semiconductors also in the moderate doping regime.


title: Constructing Sequences One Step at a Time

abstract:
  We propose a new method for constructing Turing ideals satisfying principles
of reverse mathematics below the Chain-Antichain Principle (CAC). Using this
method, we are able to prove several new separations in the presence of Weak
Konig's Lemma (WKL), including showing that CAC+WKL does not imply the thin set
theorem for pairs, and that the principle "the product of well-quasi-orders is
a well-quasi-order" is strictly between CAC and the Ascending/Descending
Sequences principle, even in the presence of WKL.


title:
Attojoule Optoelectronics for Low-Energy Information Processing and
  Communications: a Tutorial Review

abstract:
  Optics offers unique opportunities for reducing energy in information
processing and communications while resolving the problem of interconnect
bandwidth density inside machines. Such energy dissipation overall is now at
environmentally significant levels; the source of that dissipation is
progressively shifting from logic operations to interconnect energies. Without
the prospect of substantial reduction in energy per bit communicated, we cannot
continue the exponential growth of our use of information. The physics of
optics and optoelectronics fundamentally addresses both interconnect energy and
bandwidth density, and optics may be the only scalable solution to such
problems. Here we summarize the corresponding background, status,
opportunities, and research directions for optoelectronic technology and novel
optics, including sub-femtojoule devices in waveguide and novel 2D array
optical systems. We compare different approaches to low-energy optoelectronic
output devices and their scaling, including lasers, modulators and LEDs,
optical confinement approaches (such as resonators) to enhance effects, and the
benefits of different material choices, including 2D materials and other
quantum-confined structures. Beyond the elimination of line charging by the use
optical connections, the next major interconnect dissipations are in the
electronic circuits for receiver amplifiers, timing recovery and multiplexing.
We can address these through the integration of photodetectors to reduce or
eliminate receiver circuit energies, free-space optics to eliminate the need
for timing and multiplexing circuits (while solving bandwidth density
problems), and using optics generally to save power by running large
synchronous systems. One target concept is interconnects from ~ 1 cm to ~ 10 m
that have the same energy (~ 10fJ/bit) and simplicity as local electrical wires
on chip.


title: Multilinear Grammar: Ranks and Interpretations

abstract:
  Multilinear Grammar provides a framework for integrating the many different
syntagmatic structures of language into a coherent semiotically based Rank
Interpretation Architecture, with default linear grammars at each rank. The
architecture defines a Sui Generis Condition on ranks, from discourse through
utterance and phrasal structures to the word, with its sub-ranks of morphology
and phonology. Each rank has unique structures and its own semantic-pragmatic
and prosodic-phonetic interpretation models. Default computational models for
each rank are proposed, based on a Procedural Plausibility Condition:
incremental processing in linear time with finite working memory. We suggest
that the Rank Interpretation Architecture and its multilinear properties
provide systematic design features of human languages, contrasting with
unordered lists of key properties or single structural properties at one rank,
such as recursion, which have previously been been put forward as language
design features. The framework provides a realistic background for the gradual
development of complexity in the phylogeny and ontogeny of language, and
clarifies a range of challenges for the evaluation of realistic linguistic
theories and applications. The empirical objective of the paper is to
demonstrate unique multilinear properties at each rank and thereby motivate the
Multilinear Grammar and Rank Interpretation Architecture framework as a
coherent approach to capturing the complexity of human languages in the
simplest possible way.


title:
Omnidirectional Bats, Point-to-Plane Distances, and the Price of
  Uniqueness

abstract:
  We study simultaneous localization and mapping with a device that uses
reflections to measure its distance from walls. Such a device can be realized
acoustically with a synchronized collocated source and receiver; it behaves
like a bat with no capacity for directional hearing or vocalizing. In this
paper we generalize our previous work in 2D, and show that the 3D case is not
just a simple extension, but rather a fundamentally different inverse problem.
While generically the 2D problem has a unique solution, in 3D uniqueness is
always absent in rooms with fewer than nine walls. In addition to the complete
characterization of ambiguities which arise due to this non-uniqueness, we
propose a robust solution for inexact measurements similar to analogous results
for Euclidean Distance Matrices. Our theoretical results have important
consequences for the design of collocated range-only SLAM systems, and we
support them with an array of computer experiments.


title:
Statistical properties and dynamics of phenotype components in
  individual bacteria

abstract:
  Cellular phenotype is characterized by different components such as cell
size, protein content and cell cycle time. These are global variables that are
the outcome of multiple internal microscopic processes. Accordingly, they
display some universal statistical properties and scaling relations, such as
distribution collapse and relation between moments. Cell size statistics and
its relation to growth and division has been mostly studied separately from
proteins and other cellular variables. Here we present experimental and
theoretical analyses of these phenotype components in a unified framework that
reveals their correlations and interactions inside the cell. We measure these
components simultaneously in single cells over dozens of generations, quantify
their correlations, and compare population to temporal statistics. We find that
cell size and highly expressed proteins have very similar dynamics over growth
and division cycles, which result in parallel statistical properties, both
universal and individual. In particular, while distribution shapes of
fluctuations along time are common to all cells and components, other
properties are variable and remain distinct in individual cells for a
surprisingly large number of generations. These include temporal averages of
cell size and protein content, and the structure of their auto-correlation
functions. We explore possible roles of the different components in controlling
cell growth and division. We find that in order to stabilize exponential
accumulation and division of all components across generations, coupled
dynamics among them is required. Finally, we incorporate effective coupling
within the cell cycle with a phenomenological mapping across consecutive
cycles, and show that this model reproduces the entire array of experimental
observations.


title: Multi-scale spatio-temporal analysis of human mobility

abstract:
  The recent availability of digital traces generated by phone calls and online
logins has significantly increased the scientific understanding of human
mobility. Until now, however, limited data resolution and coverage have
hindered a coherent description of human displacements across different spatial
and temporal scales. Here, we characterise mobility behaviour across several
orders of magnitude by analysing ~850 individuals' digital traces sampled every
~16 seconds for 25 months with ~10 meters spatial resolution. We show that the
distributions of distances and waiting times between consecutive locations are
best described by log-normal distributions and that natural time-scales emerge
from the regularity of human mobility. We point out that log-normal
distributions also characterise the patterns of discovery of new places,
implying that they are not a simple consequence of the routine of modern life.


title: Best polynomial approximation on the unit ball

abstract:
  Let $E_n(f)_\mu$ be the error of best approximation by polynomials of degree
at most $n$ in the space $L^2(\varpi_\mu, \mathbb{B}^d)$, where $\mathbb{B}^d$
is the unit ball in $\mathbb{R}^d$ and $\varpi_\mu(x) = (1-\|x\|^2)^\mu$ for
$\mu > -1$. Our main result shows that, for $s \in \mathbb{N}$, $$ E_n(f)_\mu
\le c n^{-2s}[E_{n-2s}(\Delta^s f)_{\mu+2s} + E_{n}(\Delta_0^s f)_{\mu}], $$
where $\Delta$ and $\Delta_0$ are the Laplace and Laplace-Beltrami operators,
respectively. We also derive a bound when the right hand side contains odd
order derivatives.


title: Comparison of the Categories of Motives defined by Voevodsky and Nori

abstract:
  In this thesis we compare V. Voevodsky's geometric motives to the derived
category of M. Nori's abelian category of mixed motives by constructing a
triangulated tensor functor between them. It will be compatible with the Betti
realizations on both sides. We allow an arbitrary noetherian ring of
coefficients, but require it to be a field or a Dedekind domain for the tensor
structure on derived Nori motives to exist.
  There are three key ingredients: we present a theory of Nisnevich covers on
finite acyclic diagrams of finite correspondences, explain, following D. Rydh,
how to interpret finite correspondences as multivalued morphisms and elaborate
on M. Nori's cohomological cell structures. For the first two, we will be
working over an arbitrary regular scheme, but the last one will require that we
restrict ourselves to a subfield of the complex numbers.
  On the way we also show that smooth commutative group schemes over a normal
base automatically admit transfers, generalizing a result by M. Spiess and T.
Szamuely.


title: Finite-State Channel Models for Signal Transduction in Neural Systems

abstract:
  Information theory provides powerful tools for understanding communication
systems. This analysis can be applied to intercellular signal transduction,
which is a means of chemical communication among cells and microbes. We discuss
how to apply information-theoretic analysis to ligand-receptor systems, which
form the signal carrier and receiver in intercellular signal transduction
channels. We also discuss the applications of these results to neuroscience.


title: Towards Deep Symbolic Reinforcement Learning

abstract:
  Deep reinforcement learning (DRL) brings the power of deep neural networks to
bear on the generic task of trial-and-error learning, and its effectiveness has
been convincingly demonstrated on tasks such as Atari video games and the game
of Go. However, contemporary DRL systems inherit a number of shortcomings from
the current generation of deep learning techniques. For example, they require
very large datasets to work effectively, entailing that they are slow to learn
even when such datasets are available. Moreover, they lack the ability to
reason on an abstract level, which makes it difficult to implement high-level
cognitive functions such as transfer learning, analogical reasoning, and
hypothesis-based reasoning. Finally, their operation is largely opaque to
humans, rendering them unsuitable for domains in which verifiability is
important. In this paper, we propose an end-to-end reinforcement learning
architecture comprising a neural back end and a symbolic front end with the
potential to overcome each of these shortcomings. As proof-of-concept, we
present a preliminary implementation of the architecture and apply it to
several variants of a simple video game. We show that the resulting system --
though just a prototype -- learns effectively, and, by acquiring a set of
symbolic rules that are easily comprehensible to humans, dramatically
outperforms a conventional, fully neural DRL system on a stochastic variant of
the game.


title: Some copula inference procedures adapted to the presence of ties

abstract:
  When modeling the distribution of a multivariate continuous random vector
using the so-called \emph{copula approach}, it is not uncommon to have ties in
the coordinate samples of the available data because of rounding or lack of
measurement precision. Yet, the vast majority of existing inference procedures
on the underlying copula were both theoretically derived and practically
implemented under the assumption of no ties. Applying them nonetheless can lead
to strongly biased results. Some of the existing statistical tests can however
be adapted to provide meaningful results in the presence of ties. It is the
case of some tests of exchangeability, radial symmetry, extreme-value
dependence and goodness of fit. Detailed algorithms for computing approximate
p-values for the modified tests are provided and their finite-sample behaviors
are empirically investigated through extensive Monte Carlo experiments. An
illustration on a real-world insurance data set concludes the work.


title: Complex Laplacian based Distributed Control for Multi-Agent Network

abstract:
  The work done in this paper, proposes a complex Laplacian-based distributed
control scheme for convergence in the multi-agent network. The proposed scheme
has been designated as cascade formulation. The proposed technique exploits the
traditional method of organizing large scattered networks into smaller
interconnected clusters to optimize information flow within the network. The
complex Laplacian-based approach results in a hierarchical structure, with
formation of a meta-cluster leading other clusters in the network. The proposed
formulation enables flexibility to constrain the eigen spectra of the overall
closed-loop dynamics, ensuring desired convergence rate and control input
intensity. The sufficient conditions ensuring globally stable formation for
proposed formulation are also asserted. Robustness of the proposed formulation
to uncertainties like loss in communication links and actuator failure has also
been discussed. The effectiveness of the proposed approach is illustrated by
simulating a finitely large network of thirty vehicles.


title: Playing FPS Games with Deep Reinforcement Learning

abstract:
  Advances in deep reinforcement learning have allowed autonomous agents to
perform well on Atari games, often outperforming humans, using only raw pixels
to make their decisions. However, most of these games take place in 2D
environments that are fully observable to the agent. In this paper, we present
the first architecture to tackle 3D environments in first-person shooter games,
that involve partially observable states. Typically, deep reinforcement
learning methods only utilize visual input for training. We present a method to
augment these models to exploit game feature information such as the presence
of enemies or items, during the training phase. Our model is trained to
simultaneously learn these features along with minimizing a Q-learning
objective, which is shown to dramatically improve the training speed and
performance of our agent. Our architecture is also modularized to allow
different models to be independently trained for different phases of the game.
We show that the proposed architecture substantially outperforms built-in AI
agents of the game as well as humans in deathmatch scenarios.


title: Learning camera viewpoint using CNN to improve 3D body pose estimation

abstract:
  The objective of this work is to estimate 3D human pose from a single RGB
image. Extracting image representations which incorporate both spatial relation
of body parts and their relative depth plays an essential role in accurate3D
pose reconstruction. In this paper, for the first time, we show that camera
viewpoint in combination to 2D joint lo-cations significantly improves 3D pose
accuracy without the explicit use of perspective geometry mathematical
models.To this end, we train a deep Convolutional Neural Net-work (CNN) to
learn categorical camera viewpoint. To make the network robust against clothing
and body shape of the subject in the image, we utilized 3D computer rendering
to synthesize additional training images. We test our framework on the largest
3D pose estimation bench-mark, Human3.6m, and achieve up to 20% error reduction
compared to the state-of-the-art approaches that do not use body part
segmentation.


title:
Static vs adapted optimal execution strategies in two benchmark trading
  models

abstract:
  We consider the optimal solutions to the trade execution problem in the two
different classes of i) fully adapted or adaptive and ii) deterministic or
static strategies, comparing them. We do this in two different benchmark
models. The first model is a discrete time framework with an information flow
process, dealing with both permanent and temporary impact, minimizing the
expected cost of the trade. The second model is a continuous time framework
where the objective function is the sum of the expected cost and a value at
risk (or expected shortfall) type risk criterion. Optimal adapted solutions are
known in both frameworks from the original works of Bertsimas and Lo (1998) and
Gatheral and Schied (2011). In this paper we derive the optimal static
strategies for both benchmark models and we study quantitatively the
improvement in optimality when moving from static strategies to fully adapted
ones. We conclude that, in the benchmark models we study, the difference is not
relevant, except for extreme unrealistic cases for the model or impact
parameters. This indirectly confirms that in the similar framework of Almgren
and Chriss (2000) one is fine deriving a static optimal solution, as done by
those authors, as opposed to a fully adapted one, since the static solution
happens to be tractable and known in closed form.


title: Principled Option Learning in Markov Decision Processes

abstract:
  It is well known that options can make planning more efficient, among their
many benefits. Thus far, algorithms for autonomously discovering a set of
useful options were heuristic. Naturally, a principled way of finding a set of
useful options may be more promising and insightful. In this paper we suggest a
mathematical characterization of good sets of options using tools from
information theory. This characterization enables us to find conditions for a
set of options to be optimal and an algorithm that outputs a useful set of
options and illustrate the proposed algorithm in simulation.


title:
Dipolariton formation in quantum dot molecules strongly coupled to
  optical resonators

abstract:
  In this theoretical work, we study a double quantum dot interacting strongly
with a microcavity, while undergoing resonant tunneling. Effects of interdot
tunneling on the light-matter hybridized states are determined, and tunability
of their brightness degrees and associated dipole moments is demonstrated.
These results predict dipolariton generation in artificial molecules coupled to
optical resonators, and provide a promising scenario for control of emission
efficiency and coherence times of exciton polaritons.


title:
Inertia effects in the real-time dynamics of a quantum spin coupled to a
  Fermi sea

abstract:
  Spin dynamics in the Kondo impurity model, initiated by suddenly switching
the direction of a local magnetic field, is studied by means of the
time-dependent density-matrix renormalization group. Quantum effects are
identified by systematic computations for different spin quantum numbers $S$
and by comparing with tight-binding spin-dynamics theory for the classical-spin
Kondo model. We demonstrate that, besides the conventional precessional motion
and relaxation, the quantum-spin dynamics shows nutation, similar to a spinning
top. Opposed to semiclassical theory, however, the nutation is efficiently
damped on an extremely short time scale. The effect is explained in the
large-$S$ limit as quantum dephasing of the eigenmodes in an emergent two-spin
model that is weakly entangled with the bulk of the system. We argue that,
apart from the Kondo effect, the damping of nutational motion is essentially
the only characteristics of the quantum nature of the spin. Qualitative
agreement between quantum and semiclassical spin dynamics is found down to
$S=1/2$.


title:
On the spectrum of discrete Schr\"odinger equation with one-dimensional
  perturbation

abstract:
  We consider the spectrum of the discrete Schr\"odinger equation with
one-dimensional perturbation. We obtain the explicit form of scattering matrix
and find the exact condition of absence of singular part of the spectrum. We
calculated also the eigenvalue that appears if this condition is not true. In
the last part of our paper we give few remarks on the case of two-dimensional
perturbations.


title:
Sequential Ensemble Learning for Outlier Detection: A Bias-Variance
  Perspective

abstract:
  Ensemble methods for classification and clustering have been effectively used
for decades, while ensemble learning for outlier detection has only been
studied recently. In this work, we design a new ensemble approach for outlier
detection in multi-dimensional point data, which provides improved accuracy by
reducing error through both bias and variance. Although classification and
outlier detection appear as different problems, their theoretical underpinnings
are quite similar in terms of the bias-variance trade-off [1], where outlier
detection is considered as a binary classification task with unobserved labels
but a similar bias-variance decomposition of error.
  In this paper, we propose a sequential ensemble approach called CARE that
employs a two-phase aggregation of the intermediate results in each iteration
to reach the final outcome. Unlike existing outlier ensembles which solely
incorporate a parallel framework by aggregating the outcomes of independent
base detectors to reduce variance, our ensemble incorporates both the parallel
and sequential building blocks to reduce bias as well as variance by ($i$)
successively eliminating outliers from the original dataset to build a better
data model on which outlierness is estimated (sequentially), and ($ii$)
combining the results from individual base detectors and across iterations
(parallelly). Through extensive experiments on sixteen real-world datasets
mainly from the UCI machine learning repository [2], we show that CARE performs
significantly better than or at least similar to the individual baselines. We
also compare CARE with the state-of-the-art outlier ensembles where it also
provides significant improvement when it is the winner and remains close
otherwise.