title:
Method for identifying electromagnetically induced transparency in a
  tunable circuit quantum electrodynamics system

abstract:
  Electromagnetically induced transparency (EIT) has been realized in atomic
systems, but fulfilling the EIT conditions for artificial atoms made from
superconducting circuits is a more difficult task. Here we report an
experimental observation of the EIT in a tunable three-dimensional transmon by
probing the cavity transmission. To fulfill the EIT conditions, we tune the
transmon to adjust its damping rates by utilizing the effect of the cavity on
the transmon states. From the experimental observations, we clearly identify
the EIT and Autler-Townes splitting (ATS) regimes as well as the transition
regime in between. Also, the experimental data demonstrate that the threshold
$\Omega_{\rm AIC}$ determined by the Akaike information criterion can describe
the EIT-ATS transition better than the threshold $\Omega_{\rm EIT}$ given by
the EIT theory.


title: Muffled Semi-Supervised Learning

abstract:
  We explore a novel approach to semi-supervised learning. This approach is
contrary to the common approach in that the unlabeled examples serve to
"muffle," rather than enhance, the guidance provided by the labeled examples.
We provide several variants of the basic algorithm and show experimentally that
they can achieve significantly higher AUC than boosted trees, random forests
and logistic regression when unlabeled examples are available.


title: Information Measure as Time Complexity

abstract:
  The concept of Shannon entropy of random variables was generalized to
measurable functions in general, and to simple functions with finite values in
particular. It is shown that the information measure of a function is related
to the time complexity of search problems concerning the functions in question.
Formally, given a Turing reduction from a search problem f(x)=y to another
function g(x), the amount of information about f(x)=y provided by querying g(x)
is exactly equal to the average mutual information I(f;g). As a result, the
average number of queries is I(f=y)/I(f;g), where I(f) is amount of
self-information about the event {f=y}. In the idea case, if I(f=y)/I(f;g) is
polynomial in the size of input and the function g(x) can be computed in
polynomial time, then the problem f(x)=y also has polynomial-time algorithm. As
it turns out, our information-based complexity estimation is a natural setting
in which to study the power of randomized or probabilistic algorithms. Applying
to decision problems, our result provides a strong evidence that P=RP=BPP.
Using brute-force search as a benchmark for efficiency, our results also
support that P!=PP. Further, applying an argument similar to Carnot's work on
measuring the efficiency of an ideal heat engine in thermodynamics, it is shown
that I(f=y)/H(f) is a lower bound on query complexity of solving f(x)=y.
According to Markov's inequality, if I(f=y)/H(f) is exponential in the size of
input, then the probability of f(x)=y having polynomial-time algorithm is a
negative exponential in the size of input. This result enables us to reduce the
problem of proving FP!=FNP to the computation of the entropy of certain simple
functions, such as the subset sum function. As a result, P!=NP is provable,
answering a long-standing open problem.


title:
Filamentary flow and magnetic geometry in evolving cluster-forming
  molecular cloud clumps

abstract:
  We present an analysis of the relationship between the orientation of
magnetic fields and filaments that form in 3D magnetohydrodynamic simulations
of cluster-forming, turbulent molecular cloud clumps. We examine simulated
cloud clumps with size scales of L ~ 2-4 pc and densities of n ~ 400-1000 cm^-3
with Alfven Mach numbers near unity. We simulated two cloud clumps of different
masses, one in virial equilibrium, the other strongly gravitationally bound,
but with the same initial turbulent velocity field and similar mass-to-flux
ratio. We apply various techniques to analyze the filamentary and magnetic
structure of the resulting cloud, including the DisPerSE filament-finding
algorithm in 3D. The largest structure that forms is a 1-2 parsec-long
filament, with smaller connecting sub-filaments. We find that our simulated
clouds, wherein magnetic forces and turbulence are comparable, coherent
orientation of the magnetic field depends on the virial parameter. Subvirial
clumps undergo strong gravitational collapse and magnetic field lines are
dragged with the accretion flow. We see evidence of filament-aligned flow and
accretion flow onto the filament in the subvirial cloud. Magnetic fields
oriented more parallel in the subvirial cloud and more perpendicular in the
denser, marginally bound cloud. Radiative feedback from a 16 Msun star forming
in a cluster in one of our simulations ultimately results in the destruction of
the main filament, the formation of an HII region, and the sweeping up of
magnetic fields within an expanding shell at the edges of the HII region.


title: Analysis aspects of Ricci flow on conical surfaces

abstract:
  In this paper, we establish a framework for the analysis of linear parabolic
equations on conical surfaces and use them to study the conical Ricci flow. In
particular, we prove the long time existence of the conical Ricci flow for
general cone angle and show that this solution has the optimal regularity,
namely, the time derivatives of the conformal factor are bounded and for each
fixed time, the conformal factor has an explicit asymptotic expansion near the
cone points.


title: Bethe-Salpeter bound-state structure in Minkowski space

abstract:
  The quantitative investigation of the scalar Bethe-Salpeter equation in
Minkowski space, within the ladder-approximation framework, is extended to
include the excited states. This study has been carried out for an interacting
system composed by two massive bosons exchanging a massive scalar, by adopting
(i) the Nakanishi integral representation of the Bethe-Salpeter amplitude, and
(ii) the formally exact projection onto the null plane. Our analysis, on one
hand, confirms the reliability of the method already applied to the ground
state and, on the other one, extends the investigation from the valence
distribution in momentum space to the corresponding quantity in the
impact-parameter space, pointing out some relevant features, like (i) the
equivalence between Minkowski and Euclidean transverse-momentum amplitudes, and
(ii) the leading exponential fall-off of the valence wave function in the
impact-parameter space.


title: Dueling Bandits with Dependent Arms

abstract:
  We study dueling bandits with weak utility-based regret when preferences over
arms have a total order and carry observable feature vectors. The order is
assumed to be determined by these feature vectors, an unknown preference
vector, and a known utility function. This structure introduces dependence
between preferences for pairs of arms, and allows learning about the preference
over one pair of arms from the preference over another pair of arms. We propose
an algorithm for this setting called Comparing The Best (CTB), which we show
has constant expected cumulative weak utility-based regret. We provide a
Bayesian interpretation for CTB, an implementation appropriate for a small
number of arms, and an alternate implementation for many arms that can be used
when the input parameters satisfy a decomposability condition. We demonstrate
through numerical experiments that CTB with appropriate input parameters
outperforms all benchmarks considered.


title:
Kernel ridge vs. principal component regression: minimax bounds and
  adaptability of regularization operators

abstract:
  Regularization is an essential element of virtually all kernel methods for
nonparametric regression problems. A critical factor in the effectiveness of a
given kernel method is the type of regularization that is employed. This
article compares and contrasts members from a general class of regularization
techniques, which notably includes ridge regression and principal component
regression. We derive an explicit finite-sample risk bound for
regularization-based estimators that simultaneously accounts for (i) the
structure of the ambient function space, (ii) the regularity of the true
regression function, and (iii) the adaptability (or qualification) of the
regularization. A simple consequence of this upper bound is that the risk of
the regularization-based estimators matches the minimax rate in a variety of
settings. The general bound also illustrates how some regularization techniques
are more adaptable than others to favorable regularity properties that the true
regression function may possess. This, in particular, demonstrates a striking
difference between kernel ridge regression and kernel principal component
regression. Our theoretical results are supported by numerical experiments.


title: Optimal dynamic mechanisms with ex-post IR via bank accounts

abstract:
  Lately, the problem of designing multi-stage dynamic mechanisms has been
shown to be both theoretically challenging and practically important. In this
paper, we consider the problem of designing revenue optimal dynamic mechanism
for a setting where an auctioneer sells a set of items to a buyer in multiple
stages. At each stage, there could be multiple items for sale but each item can
only appear in one stage. The type of the buyer at each stage is thus a
multi-dimensional vector characterizing the buyer's valuations of the items at
that stage and is assumed to be stage-wise independent.
  In particular, we propose a novel class of mechanisms called bank account
mechanisms. Roughly, a bank account mechanism is no different from any
stage-wise individual mechanism except for an augmented structure called bank
account, a real number for each node that summarizes the history so far. We
first establish that the optimal revenue from any dynamic mechanism in this
setting can be achieved by a bank account mechanism, and we provide a simple
characterization of the set of incentive compatible and ex-post individually
rational bank account mechanisms. Based on these characterizations, we then
investigate the problem of finding the (approximately) optimal bank account
mechanisms. We prove that there exists a simple, randomized bank account
mechanism that approximates optimal revenue up to a constant factor. Our result
is general and can accommodate previous approximation results in single-shot
multi-dimensional mechanism design. Based on the previous mechanism, we further
show that there exists a deterministic bank account mechanism that achieves
constant-factor approximation as well. Finally, we consider the problem of
computing optimal mechanisms when the type space is discrete and provide an
FPTAS via linear and dynamic programming.


title:
Surviving an "Eternal September" - How an Online Community Managed a
  Surge of Newcomers

abstract:
  We present a qualitative analysis of interviews with participants in the
NoSleep community within Reddit where millions of fans and writers of horror
fiction congregate. We explore how the community handled a massive, sudden, and
sustained increase in new members. Although existing theory and stories like
Usenet's infamous "Eternal September" suggest that large influxes of newcomers
can hurt online communities, our interviews suggest that NoSleep survived
without major incident. We propose that three features of NoSleep allowed it to
manage the rapid influx of newcomers gracefully: (1) an active and
well-coordinated group of administrators, (2) a shared sense of community which
facilitated community moderation, and (3) technological systems that mitigated
norm violations. We also point to several important trade-offs and limitations.


title:
Spatial Phase and Amplitude Structuring of Beams Using a Combination of
  Multiple Orthogonal Spatial Functions with Complex Coefficients

abstract:
  Analogous to time signals that can be composed of multiple frequency
functions, we use uniquely structured orthogonal spatial modes to create
different beam shapes. We tailor the spatial structure by judiciously choosing
a weighted combination of multiple modal states within an orthogonal basis set,
and we can tunably create beam phase and intensity "shapes" that are not
otherwise readily achievable. As an example shape, we use a series of
orbital-angular-momentum (OAM) functions with adjustable complex weights to
create a reconfigurable spatial region of higher localized power as compared to
traditional beam combining. We simulate a structured beam created by coherently
combining several orthogonal OAM beams with different complex weights, and we
achieve a >10X localized power density enhancement with 19 beams. Additionally,
we can create unique shapes by passing a single beam through a specially
designed phase and intensity mask that contains the combination of multiple OAM
functions each with complex weights. Using this approach, we experimentally
demonstrate a ~2.5X localized power density increase when utilizing 9
functions.


title: Balanced pairs of operators and their relative index

abstract:
  We show that the K_1 group of a C*-algebra $A$ can be defined as homotopy
classes of pairs, called balanced, of not necessarily unitary matrices over $A$
that have equal defects from being unitary. We also consider pairs of order
zero pseudodifferential operators, not necessarily elliptic, with symbols being
a balanced pair. A relative index is defined for such pairs of operators and it
equals the topological index of the pair of their symbols.


title: Smart Societies: From Citizens as Sensors to Collective Action

abstract:
  Social media has become globally ubiquitous, transforming how people are
networked and mobilized. This forum explores research and applications of these
new networked publics at individual, organizational, and societal levels.


title: The effect of environment on the structure of disc galaxies

abstract:
  We study the influence of environment on the structure of disc galaxies,
using \texttt{IMFIT} to measure the g- and r-band structural parameters of the
surface-brightness profiles for $\sim$700 low-redshift (z$<$0.063) cluster and
field disc galaxies with intermediate stellar mass (0.8 $\times$ 10$^{10}$
$M_{\odot}$ $<$ $M_{\star}$ $<$ 4 $\times$ 10$^{10}$ $M_{\odot}$) from the
Sloan Digital Sky Survey, DR7. Based on this measurement, we assign each galaxy
to a surface-brightness profile type (Type I $\equiv$ single-exponential, Type
II $\equiv$ truncated, Type III $\equiv$ anti-truncated). In addition, we
measure (g-r) restframe colour for disc regions separated by the break radius.
Cluster disc galaxies (at the same stellar mass) have redder (g-r) colour by
$\sim$0.2 mag than field galaxies. This reddening is slightly more pronounced
outside the break radius. Cluster disc galaxies also show larger global
S\'ersic-indices and are more compact than field discs, both by $\sim$15\%.
This change is connected to a flattening of the (outer) surface-brightness
profile of Type I and - more significantly - of Type III galaxies by $\sim$8\%
and $\sim$16\%, respectively, in the cluster environment compared to the field.
We find fractions of Type I, II and III of (6$\pm$2)\%, (66$\pm$4)\% and
(29$\pm$4)\% in the field and (15$_{-4}^{+7}$)\%, (56$\pm$7)\% and (29$\pm$7)\%
in the cluster environment, respectively. We suggest that the larger abundance
of Type I galaxies in clusters (matched by a corresponding decrease in the Type
II fraction) could be the signature of a transition between Type II and Type I
galaxies produced/enhanced by environment-driven mechanisms.


title:
A Human-Centered Approach to Data Privacy : Political Economy, Power,
  and Collective Data Subjects

abstract:
  Researchers find weaknesses in current strategies for protecting privacy in
large datasets. Many anonymized datasets are reidentifiable, and norms for
offering data subjects notice and consent over emphasize individual
responsibility. Based on fieldwork with data managers in the City of Seattle, I
identify ways that these conventional approaches break down in practice.
Drawing on work from theorists in sociocultural anthropology, I propose that a
Human Centered Data Science move beyond concepts like dataset identifiability
and sensitivity toward a broader ontology of who is implicated by a dataset,
and new ways of anticipating how data can be combined and used.


title:
Light Baryons Mass in a Non-Relativistic Quark Model within an
  Hypercentral Power Low Potential

abstract:
  In this work, we calculated the baryon mass within a non-relativistically
quark model using an approach based on the G\"ursey Radicati mass formula (GR).
The average energy value of each SU(6) multiplet is described using the SU(6)
invariant interaction given by a hypercentral potential. In our series studies
we investigate different interactions and situations to gain the best possible
model. This goal can be obtained by checking and studying various potentials in
different situations. In this paper we present the solution of the
Schr\"odinger equation with an hypercentral power low potential. The results of
our model (the combination of our proposed hypercentral Potential and
generalized GR mass formula to description of the spectrum) show that the
strange and non-strange baryons spectra are in general fairly well reproduced.
The overall good description of the mass which we obtain shows that our model
can also be used to give a fair description of the energies of the excited
multiplets up to three GeV and the position of the Roper resonances of the
nucleon.


title: Landau-Lifshitz Equation with Affine Control

abstract:
  The Landau-Lifshitz equation is a coupled set of nonlinear partial
differential equations that describes the dynamics of magnetization in a
ferromagnet. This equation has an infinite number of stable equilibria.
Steering the system from one equilibrium to another is a problem of both
theoretical and practical interest. Since the objective is to steer between
equilibria, approaches based on linearization are not appropriate. It is proven
that affine proportional control can be used to steer the system from an
arbitrary initial state, including an equilibrium point, to a specified
equilibrium point. The second point becomes a globally asymptotically stable
equilibrium of the controlled system. The control also removes hysteresis from
the Landau-Lifshitz equation. These results are illustrated with simulations.


title:
The effect of Microstructure in Exchange Decoupling of SmCo5/Co
  bi-layers at low temperatures

abstract:
  Here, we investigated the influence of grain formation on the magnetization
reversal of SmCo5/Co at low temperature. A set of SmCo5/Co bi-layer samples
were fabricated under identical conditions on MgO(100) and glass substrates
with a Cr underlayer. Analysis of each magnetic layer by an Atomic Force
Microscope (AFM) reveals that MgO(100) results small and uniform grain
formation of 23 nm in contrast to 57 nm on glass, and x-ray diffraction studies
show that the sample on MgO(100) has high crystallinity with SmCo5(11 0) phase.
At room temperature, both samples exhibit good hard magnetic properties with
coercivity (HC) of 13.2 kOe and 12.5 kOe, and energy products (BH)max of 14.5
MGOe and 5.3 MGOe for samples on MgO(100) and glass, respectively. Low
temperature hysteresis measurements show an exchange decoupling at low
temperatures for the sample on glass, and this is due to the formation of large
grains on glass that reduces the effective inter-grain exchange coupling
between phases.


title: Asymmetric vector mesons produced in nuclear collisions

abstract:
  It is argued that the experimentally observed phenomenon of asymmetric shapes
of vector mesons produced in nuclear media during high energy nucleus-nucleus
collisions can be explained as Fano-Feshbach resonances. It has been observed
that the mass distributions of lepton pairs created at meson decays decline
from the traditional Breit-Wigner shape with some excess in the low-mass wing
of the resonance. It is clear that the whole phenomenon is related to some
interaction with the nuclear medium. Moreover, it can be further detalized in
quantum mechanics as the interference of direct and continuum states in
Fano-Feshbach effect. To reveal the nature of the interaction it is proposed to
use a phenomenological model of the additional contribution due to Cherenkov
gluons. They can be created because of the excess of the refractivity index
over 1 just in the low-mass wing as required by the classical Cherenkov
treatment. In quantum mechanics, this requirement is related to the positive
real part of the interaction amplitude in this wing. The corresponding
parameters are found from the comparison with $\rho $-meson data and admit
reasonable explanation.


title:
A Simplified Sub-Nyquist Receiver Architecture for Joint DOA and
  Frequency Estimation

abstract:
  Joint estimation of carrier frequency and direction of arrival (DOA) for
multiple signals has been found in many practical applications such as
Cognitive Radio (CR). However, Nyquist sampling mechanism is costly or
implemented due to wide spectrum range. Taking advantage of sub-Nyquist
sampling technology, some array receiver architectures are proposed to realize
joint estimation of carrier frequency and DOA. To further decrease equivalent
sampling rate and hardware complexity, we propose a simplifying receiver
architecture based on our previous work. We come up with joint DOA and
frequency estimation algorithms for the novel architecture. The simulations
demonstrate that the receiver architecture and the proposed approaches are
feasible.


title: Computing Overlaps of Two Quadrilateral Mesh Of the Same Connectivity

abstract:
  An exact conservative remapping scheme requires overlaps between two meshes
and a reconstruction scheme on the old cells (Lagrangian mesh). While the are
intensive discussion on reconstruction schemes, there are relative sparse
discussion on how to calculate overlaps of two grids. Computing the exact
overlaps was believed complicated and often be avoided. This paper introduces
the mathematical formulation of such a problem and tools to solve the problem.
We propose methods to calculate the overlaps of two dismissable general
quadrilateral mesh of the same logically structure in a planar domain. The
quadrilateral polygon intersection problem is reduced to as a problem that how
an edge in a new mesh intersects with a local frame which consists at most 7
connected edges in the old mesh. As such, locality of the method is persevered.
The alternative direction technique is applied to reduce the dimension of the
searching space. It reduces more than 256 possible intersections between a new
cell with the old tessellation to 34 (17 when considering symmetry)
programmable intersections between an edge and an local frame whenever the
intersection between the old and new cell does not degenerate. At the same
time, we shall how the computational amount of the overlaps depends on the
underlying problem in terms of singular intersection points. A simple and
detailed classification on the type of overlaps is presented, according to
classification, degeneracy of an overlap can be easily identified.


title: A Simons' type formula for cmc surfaces in homogeneous $3$-manifolds

abstract:
  In this paper, we give a Simons' type formula for the cmc surfaces in
homogeneous $3$-manifolds $E(\kappa,\tau)$, $\tau\neq0$. As an application, we
give a rigidity result in the case of $\kappa> 4\tau^2$ for the cmc surfaces
under a pinching assumption of the second fundamental form.


title: Charged rotating black holes at large D

abstract:
  We study odd dimensional charged equally rotating black holes in the
Einstein-Maxwell theory with/without a cosmological constant by using the large
D expansion method, where D is a spacetime dimension. Solving the
Einstein-Maxwell equations in the 1/D expansion we obtain the large D effective
equations for charged equally rotating black holes. The effective equations
describe the nonlinear dynamics of charged equally rotating black holes.
Especially the perturbation analysis of the effective equations gives analytic
formula for quasinormal mode frequencies, and we can show charged equally
rotating black holes have instabilities. As one interesting feature of
instabilities, we observe that the ultraspinning instability of neutral equally
rotating black holes in de Sitter is connected with the instability of de
Sitter Reissner-Nordstrom black hole in a rotation-charge plane of the solution
parameter space. So these instabilities have same origin as dynamical
properties of charged rotating black holes. We also give perturbation analysis
by a small charge for even dimensional equally rotating black holes.


title:
Quasisymmetric embedding of the integer set and its quasiconformal
  extension

abstract:
  We prove that an injection from the integer set into the real line admits a
quasiconformal extension to the complex plane if and only if it is
quasisymmetric.


title:
A Channelized Binning Method for Extraction of Dominant Color Pixel
  Value

abstract:
  The Color is one of the most important and easily identifiable features for
describing the visual content. The MPEG standard has developed a number of
descriptors that covers different aspects of the visual content. The Dominant
color descriptor is one of them. This paper proposes a channelized binning
approach a novel method for extraction of the dominant color pixel value which
is a variant of the dominant color descriptor. The Channelized binning method
treats the problem as a statistical problem and tries to avoid color
quantization and interpolation guessing of number and centroid of dominant
colors. Channelized binning is an iterative approach which automatically
estimates the number of dominant pixel values and their centroids. It operates
on 24 bit full RGB color space, by considering one color channel at a time and
hence avoiding the color quantization. Results show that the proposed method
can successfully extract dominant color pixel values.


title:
Video Key Frame Extraction using Entropy value as Global and Local
  Feature

abstract:
  Key frames play an important role in video annotation. It is one of the
widely used methods for video abstraction as this will help us for processing a
large set of video data with sufficient content representation in faster way.
In this paper a novel approach for key-frame extraction using entropy value is
proposed. The proposed approach classifies frames based on entropy values as
global feature and selects frame from each class as representative key-frame.
It also eliminates redundant frames from selected key-frames using entropy
value as local feature. Evaluation of the approach on several video clips has
been presented. Results show that the algorithm is successful in helping
annotators automatically identify video key-frames.


title:
Hilbert Manifold Structure of The Set of Solutions of Constraint
  Equations For Coupled Einstein and Scalar Fields

abstract:
  In this paper, we prove that the set of solutions of constraint equations for
coupled Einstein and scalar fields in classical general relativity possesses
Hilbert manifold structure. We follow the work of R. Bartnik [2] and use
weighted Sobolev spaces and Implicit Function Theorem to prove our results.


title: New Constructions of MDS Symbol-Pair Codes

abstract:
  Motivated by the application of high-density data storage technologies,
symbol-pair codes are proposed to protect against pair-errors in symbol-pair
channels, whose outputs are overlapping pairs of symbols. The research of
symbol-pair codes with the largest minimum pair-distance is interesting since
such codes have the best possible error-correcting capability. A symbol-pair
code attaining the maximal minimum pair-distance is called a maximum distance
separable (MDS) symbol-pair code. In this paper, we focus on constructing
linear MDS symbol-pair codes over the finite field $\mathbb{F}_{q}$. We show
that a linear MDS symbol-pair code over $\mathbb{F}_{q}$ with pair-distance $5$
exists if and only if the length $n$ ranges from $5$ to $q^2+q+1$. As for codes
with pair-distance $6$, length ranging from $6$ to $q^{2}+1$, we construct
linear MDS symbol-pair codes by using a configuration called ovoid in
projective geometry. With the help of elliptic curves, we present a
construction of linear MDS symbol-pair codes for any pair-distance $d+2$ with
length $n$ satisfying $7\le d+2\leq n\le q+\lfloor
2\sqrt{q}\rfloor+\delta(q)-3$, where $\delta(q)=0$ or $1$.


title: Using history matching for prior choice

abstract:
  It can be important in Bayesian analyses of complex models to construct
informative prior distributions which reflect knowledge external to the data at
hand. Nevertheless, how much prior information an analyst can elicit from an
expert will be limited due to constraints of time, cost and other factors. This
paper develops effective numerical methods for exploring reasonable choices of
a prior distribution from a parametric class, when prior information is
specified in the form of some limited constraints on prior predictive
distributions, and where these prior predictive distributions are analytically
intractable. The methods developed may be thought of as a novel application of
the ideas of history matching, a technique developed in the literature on
assessment of computer models. We illustrate the approach in the context of
logistic regression and sparse signal shrinkage prior distributions for
high-dimensional linear models.


title: The associativity rule in pathwise functional It\^o calculus

abstract:
  In this paper we establish the associativity property of the pathwise It\^o
integral in a functional setting for continuous integrators. Here,
associativity refers to the computation of the It\^o differential of an It\^o
integral, by means of the intuitive cancellation of the It\^o differential and
integral signs.


title: L\'evy-driven GPS queues with heavy-tailed input

abstract:
  In this paper we derive exact large-buffer asymptotics for a two-class
Generalized Processor Sharing (GPS) model, under the assumption that the input
traffic streams generated by both classes correspond to heavy-tailed L\'evy
processes. Four scenarios need to be distinguished, which differ in terms of
(i)~the level of heavy-tailedness of the driving L\'evy processes as well as
(ii)~the values of the corresponding mean rates relative to the GPS weights.
The derived results are illustrated by two important special cases, in which
the queues' inputs are modeled by heavy-tailed compound Poisson processes and
by $\alpha$-stable L\'evy motions.


title: Approximation of barter exchanges with cycle length constraints

abstract:
  We explore the clearing problem in the barter exchange market. The problem,
described in the terminology of graph theory, is to find a set of
vertex-disjoint, length-restricted cycles that maximize the total weight in a
weighted digraph. The problem has previously been shown to be NP-hard. We
advance the understanding of this problem by the following contributions.
  We prove three constant inapproximability results for this problem. For the
weighted graphs, we prove that it is NP-hard to approximate the clearing
problem within a factor of 14/13 under general length constraints and within a
factor of 434/433 when the cycle length is not longer than 3. For the
unweighted graphs, we prove that this problem is NP-hard to approximate within
a factor of 698/697.
  For the unweighted graphs when the cycle length is not longer than 3, we
design and implement two simple and practical algorithms. Experiments on
simulated data suggest that these algorithms yield excellent performances.


title: Analysing the Effects of Routing Centralization on BGP Convergence Time

abstract:
  Software-defined networking (SDN) has improved the routing functionality in
networks like data centers or WANs. Recently, several studies proposed to apply
the SDN principles in the Internet's inter-domain routing as well. This could
offer new routing opportunities and improve the performance of BGP, which can
take minutes to converge to routing changes.
  Previous works have demonstrated that centralization can benefit the
functionality of BGP, and improve its slow convergence that causes severe
packet losses and performance degradation. However, due to (a) the fact that
previous works mainly focus on system design aspects, and (b) the lack of real
deployments, it is not clearly understood yet to what extent inter-domain SDN
can improve performance.
  To this end, in this work, we make the first effort towards analytically
studying the effects of routing centralization on the performance of
inter-domain routing, and, in particular, the convergence time of BGP.
Specifically, we propose a Markovian model for inter-domain networks, where a
subset of nodes (domains) coordinate to centralize their inter-domain routing.
We then derive analytic results that quantify the BGP convergence time under
various network settings (like, SDN penetration, topology, BGP configuration,
etc.). Our analysis and results facilitate the performance evaluation of
inter-domain SDN networks, which have been studied (till now) only through
simulations/emulations that are known to suffer from high time/resource
requirements and limited scalability.


title: Many-body breakdown of indirect gap in topological Kondo insulators

abstract:
  We show that the inclusion of nonlocal correlation effects in a variational
wave function for the ground state of a topological Anderson lattice
Hamiltonian is capable of describing both topologically trivial insulating
phases and nontrivial ones characterized by an indirect gap, as well as its
closure at the transition into a metallic phase. The method, though applied to
an oversimplified model, thus captures the metallic and insulating states that
are indeed observed in a variety of Kondo semiconductors, while accounting for
topologically nontrivial band structures.


title: Fast simulation of Brownian dynamics in a crowded environment

abstract:
  Brownian dynamics simulations are an increasingly popular tool for
understanding spatially-distributed biochemical reaction systems. Recent
improvements in our understanding of the cellular environment show that volume
exclusion effects are fundamental to reaction networks inside cells. These
systems are frequently studied by incorporating inert hard spheres (crowders)
into three-dimensional Brownian dynamics simulations, however these methods are
extremely slow owing to the sheer number of possible collisions between
particles. Here we propose a rigorous "crowder-free" method to dramatically
increase simulation speed for crowded biochemical reaction systems by
eliminating the need to explicitly simulate the crowders. We consider both the
case where the reactive particles are point particles, and where they
themselves occupy a volume. We use simulations of simple chemical reaction
networks to confirm that our simplification is just as accurate as the original
algorithm, and that it corresponds to a large speed increase.


title: Worms and Spiders: Reflection calculi and ordinal notation systems

abstract:
  We give a general overview of ordinal notation systems arising from
reflection calculi, and extend the to represent impredicative ordinals up to
those representable using Buchholz-style collapsing functions.


title: Classical equation of motion and Anomalous dimensions at leading order

abstract:
  Motivated by a recent paper by Rychkov-Tan \cite{Rychkov:2015naa}, we
calculate the anomalous dimensions of the composite operators at the leading
order in various models including a $\phi^3$-theory in $(6-\epsilon)$
dimensions. The method presented here relies only on the classical equation of
motion and the conformal symmetry. In case that only the leading expressions of
the critical exponents are of interest, it is sufficient to reduce the
multiplet recombination discussed in \cite{Rychkov:2015naa} to the classical
equation of motion. We claim that in many cases the use of the classical
equations of motion and the CFT constraint on two- and three-point functions
completely determine the leading behavior of the anomalous dimensions at the
Wilson-Fisher fixed point without any input of the Feynman diagrammatic
calculation. The method developed here is closely related to the one presented
in \cite{Rychkov:2015naa} but based on a more perturbative point of view.


title: On monogenic mappings of the quaternionic variables

abstract:
  In the paper [1] we consider a new class, so-called, $G$-monogenic
(differentiable in the sense of Gateaux) quaternionic mappings. In the present
paper we introduce quaternionic $H$-monogenic (differentiable in the sense of
Hausdorff) mappings and establish the relation between $G$-monogenic and
$H$-monogenic mappings. The equivalence of different definitions of
$G$-monogenic mapping is proved.


title: k-neighborhood for Cellular Automata

abstract:
  A neighborhood for d-dimensional cellular automata is introduced that spans
the range from von Neumann to Moore neighborhood using a parameter which
represents the dimension of hypercubes connecting neighboring cells. The
neighborhood is extended to include a concept of radius. The number of
neighbors is calculated. For diamond-shaped neighborhoods, a sequence is
obtained whose partial sums equal Delannoy numbers.


title:
Interband characterization and electronic transport control of
  nanoscaled GeTe/Sb$_2$Te$_3$ superlattices

abstract:
  The extraordinary electronic and optical properties of the
crystal-to-amorphous transition in phase-change materials led to important
developments in memory applications. A promising outlook is offered by
nanoscaling such phase-change structures. Following this research line, we
study the interband optical transmission spectra of nanoscaled
GeTe/Sb$_2$Te$_3$ chalcogenide superlattice films. We determine, for films with
varying stacking sequence and growth methods, the density and scattering time
of the free electrons, and the characteristics of the valence-to-conduction
transition. It is found that the free electron density decreases with
increasing GeTe content, for sub-layer thickness below $\sim$3 nm. A simple
band model analysis suggests that GeTe and Sb$_2$Te$_3$ layers mix, forming a
standard GeSbTe alloy buffer layer. We show that it is possible to control the
electronic transport properties of the films by properly choosing the
deposition layer thickness and we derive a model for arbitrary film stacks.


abstract:
  Collaborative Topic Regression (CTR) combines ideas of probabilistic matrix
factorization (PMF) and topic modeling (e.g., LDA) for recommender systems,
which has gained increasing successes in many applications. Despite enjoying
many advantages, the existing CTR algorithms have some critical limitations.
First of all, they are often designed to work in a batch learning manner,
making them unsuitable to deal with streaming data or big data in real-world
recommender systems. Second, the document-specific topic proportions of LDA are
fed to the downstream PMF, but not reverse, which is sub-optimal as the rating
information is not exploited in discovering the low-dimensional representation
of documents and thus can result in a sub-optimal representation for
prediction. In this paper, we propose a novel scheme of Online Bayesian
Collaborative Topic Regression (OBCTR) which is efficient and scalable for
learning from data streams. Particularly, we {\it jointly} optimize the
combined objective function of both PMF and LDA in an online learning fashion,
in which both PMF and LDA tasks can be reinforced each other during the online
learning process. Our encouraging experimental results on real-world data
validate the effectiveness of the proposed method.


title: A Remark to the Theorem of Le Calvez and Yoccoz

abstract:
  The theorem of Le Calvez and Yoccoz states that there are no minimal
homeomorphisms on the finite punctered 2-dimensional sphere S 2 . We show that
this does not hold for other surfaces. Moreover, we discuss why the
fast-conjugation-method fails in the most cases to construct such
homeomorphisms. This article based on an old unpublished article
(Quasi-Minimal, Pseudo-Minimal Systems and Dense Orbits) with incorrect
results.


title: On the Optimality of Time Division for Broadcast Channels

abstract:
  We provide a necessary and sufficient condition that under some technical
assumption characterizes all two-receiver broadcast channels for which time
division is optimal for transmission of private messages.


title:
An Ensemble Kalman Filter Implementation Based on Modified Cholesky
  Decomposition for Inverse Covariance Matrix Estimation

abstract:
  This paper develops an efficient implementation of the ensemble Kalman filter
based on a modified Cholesky decomposition for inverse covariance matrix
estimation. This implementation is named EnKF-MC. Background errors
corresponding to distant model components with respect to some radius of
influence are assumed to be conditionally independent. This allows to obtain
sparse estimators of the inverse background error covariance matrix. The
computational effort of the proposed method is discussed and different
formulations based on various matrix identities are provided. Furthermore, an
asymptotic proof of convergence with regard to the ensemble size is presented.
In order to assess the performance and the accuracy of the proposed method,
experiments are performed making use of the Atmospheric General Circulation
Model SPEEDY. The results are compared against those obtained using the local
ensemble transform Kalman filter (LETKF). Tests are performed for dense
observations ($100\%$ and $50\%$ of the model components are observed) as well
as for sparse observations (only $12\%$, $6\%$, and $4\%$ of model components
are observed). The results reveal that the use of modified Cholesky for inverse
covariance matrix estimation can reduce the impact of spurious correlations
during the assimilation cycle, i.e., the results of the proposed method are of
better quality than those obtained via the LETKF in terms of root mean square
error.


title: Finite-size scaling at infinite-order phase transitions

abstract:
  For systems with infinite-order phase transitions, in which an order
parameter smoothly becomes nonzero, a new observable for finite-size scaling
analysis is suggested. By construction this new observable has the favourable
property of diverging at the critical point. Focussing on the example of the
F-model we compare the analysis of this observable with that of another
observable, which is also derived from the order parameter but does not
diverge, as well as that of the associated susceptibility. We discuss the
difficulties that arise in the finite-size scaling analysis of such systems. In
particular we show that one may reach incorrect conclusions from large-system
size extrapolations of observables that are not known to diverge at the
critical point. Our work suggests that one should base finite-size scaling
analyses for infinite-order phase transitions only on observables that are
guaranteed to diverge.


title:
Light propagation in the gravitational field of N arbitrarily moving
  bodies in the 1.5PN approximation for high-precision astrometry

abstract:
  High-precision astrometry on sub-micro-arcsecond level in angular resolution
requires accurate determination of the trajectory of a light-signal from the
celestial light source through the gravitational field of the Solar system
toward the observer. In this investigation the light trajectory in the
gravitational field of N moving bodies is determined in the 1.5 post-Newtonian
approximation. In the approach presented two specific issues of particular
importance are accounted for:
  (1) According to the recommendations of International Astronomical Union, the
metric of the Solar system is expressed in terms of intrinsic mass-multipoles
and intrinsic spin-multipoles of the massive bodies, allowing for arbitrary
shape, inner structure and rotational motion of the massive bodies of the Solar
system.
  (2) The Solar system bodies move along arbitrary worldlines which can later
be specified by Solar system ephemeris.
  The presented analytical solution for light trajectory is a primary
requirement for extremely high-precision astrometry on sub-micro-arcsecond
level of accuracy and associated massive computations in astrometric data
reduction. An estimation of the numerical magnitude for time delay and light
deflection of the leading multipoles is given.


title:
Computational Estimate Visualisation and Evaluation of Agent Classified
  Rules Learning System

abstract:
  Student modelling and agent classified rules learning as applied in the
development of the intelligent Preassessment System has been presented in
[10],[11]. In this paper, we now demystify the theory behind the development of
the pre-assessment system followed by some computational experimentation and
graph visualisation of the agent classified rules learning algorithm in the
estimation and prediction of classified rules. In addition, we present some
preliminary results of the pre-assessment system evaluation. From the results,
it is gathered that the system has performed according to its design
specification.


title:
Towards a polynomial basis of the algebra of peak quasisymmetric
  functions

abstract:
  Hazewinkel proved the Ditters conjecture that the algebra of quasisymmetric
functions over the integers is free commutative by constructing a nice
polynomial basis. In this paper we prove a structure theorem for the algebra of
peak quasisymmetric functions (PQSym) over the integers. It provides a
polynomial basis of PQSym over the rational field, different from Hsiao's
basis, and implies the freeness of PQSym over its subring of symmetric
functions spanned by Schur's Q-functions.


title: Alternative asymptotics for cointegration tests in large VARs

abstract:
  Johansen's (1988, 1991) likelihood ratio test for cointegration rank of a
Gaussian VAR depends only on the squared sample canonical correlations between
current changes and past levels of a simple transformation of the data. We
study the asymptotic behavior of the empirical distribution of those squared
canonical correlations when the number of observations and the dimensionality
of the VAR diverge to infinity simultaneously and proportionally. We find that
the distribution almost surely weakly converges to the so-called Wachter
distribution. This finding provides a theoretical explanation for the observed
tendency of Johansen's test to find "spurious cointegration". It also sheds
light on the workings and limitations of the Bartlett correction approach to
the over-rejection problem. We propose a simple graphical device, similar to
the scree plot, for a preliminary assessment of cointegration in
high-dimensional VARs.


title: Sparse Coding and Counting for Robust Visual Tracking

abstract:
  In this paper, we propose a novel sparse coding and counting method under
Bayesian framwork for visual tracking. In contrast to existing methods, the
proposed method employs the combination of L0 and L1 norm to regularize the
linear coefficients of incrementally updated linear basis. The sparsity
constraint enables the tracker to effectively handle difficult challenges, such
as occlusion or image corruption. To achieve realtime processing, we propose a
fast and efficient numerical algorithm for solving the proposed model. Although
it is an NP-hard problem, the proposed accelerated proximal gradient (APG)
approach is guaranteed to converge to a solution quickly. Besides, we provide a
closed solution of combining L0 and L1 regularized representation to obtain
better sparsity. Experimental results on challenging video sequences
demonstrate that the proposed method achieves state-of-the-art results both in
accuracy and speed.


title: Optimal Rates for Multi-pass Stochastic Gradient Methods

abstract:
  We analyze the learning properties of the stochastic gradient method when
multiple passes over the data and mini-batches are allowed. We study how
regularization properties are controlled by the step-size, the number of passes
and the mini-batch size. In particular, we consider the square loss and show
that for a universal step-size choice, the number of passes acts as a
regularization parameter, and optimal finite sample bounds can be achieved by
early-stopping. Moreover, we show that larger step-sizes are allowed when
considering mini-batches. Our analysis is based on a unifying approach,
encompassing both batch and stochastic gradient methods as special cases. As a
byproduct, we derive optimal convergence results for batch gradient methods
(even in the non-attainable cases).


title:
User-based solutions for increasing level of service in bike-sharing
  transportation systems

abstract:
  Bike-sharing transportation systems have been well studied from a top-down
viewpoint, either for an optimal conception of the system, or for a better
statistical understanding of their working mechanisms in the aim of the
optimization of the management strategy. Yet bottom-up approaches that could
include behavior of users have not been well studied so far. We propose an
agent-based model for the short time evolution of a bike-sharing system, with a
focus on two strategical parameters that are the role of the quantity of
information users have on the all system and the propensity of user to walk
after having dropped their bike. We implement the model in a general way so it
is applicable to every system as soon as data are available in a certain
format. The model of simulation is parametrized and calibrated on processed
real time-series of bike movements for the system of Paris. After showing the
robustness of the simulations by validating internally and externally the
model, we are able to test different user-based strategies for an increase of
the level of service. In particular, we show that an increase of user
information can have significant impact on the homogeneity of repartition of
bikes in docking stations, and, what is important for a future implementation
of the strategy, that an action on only 30% of regular users is enough to
obtain most of the possible amelioration.


title: On Erd\H{o}s constant

abstract:
  In 1944, P. Erd\H{o}s \cite{1} proved that if $n$ is a large highly composite
number (HCN) and $n_1$ is the next HCN, then $$n<n_1<n+n(\log n)^{-c},$$ where
$c>0$ is a constant. In this paper, using numerical results by D. A. Corneth,
we show that most likely $c<1.$


title: Gromov-Witten Theory of Quotient of Fermat Calabi-Yau varieties

abstract:
  We construct a global B-model for weighted homogeneous polynomials based on
K. Saito's theory of primitive forms. Our main motivation is to give a rigorous
statement of the so called global mirror symmetry conjecture relating
Gromov-Witten invariants and Fan--Jarvis--Ruan--Witten invariants. Furthermore,
our construction allows us to generalize the notion of a quasi-modular form and
holomorphic anomaly equations. Finally, we prove the global mirror symmetry
conjecture for the Fermat polynomials.


title:
Potential thermoelectric materials $\mathrm{CsMI_3}$ (M=Sn and Pb) in
  perovskite structures from the first-principles calculations

abstract:
  The thermoelectric properties of halide perovskites $\mathrm{CsMI_3}$ (M=Sn
and Pb) are investigated from a combination of first-principles calculations
and semiclassical Boltzmann transport theory by considering both the electron
and phonon transport. The electronic part is performed using a modified Becke
and Johnson (mBJ) exchange potential, including spin-orbit coupling (SOC),
while the phonon part is computed using generalized gradient approximation
(GGA). It is found that SOC has remarkable detrimental effect on n-type power
factor, while has a negligible influence in p-type doping, which can be
explained by considering SOC effect on conduction and valence bands. Calculated
results show exceptionally low lattice thermal conductivities in
$\mathrm{CsSnI_3}$ and $\mathrm{CsPbI_3}$, and the corresponding
room-temperature lattice thermal conductivity is 0.54 $\mathrm{W m^{-1}
K^{-1}}$ and 0.25 $\mathrm{W m^{-1} K^{-1}}$. At 1000 K, the maximal figure of
merit $ZT$ is up to 0.63 and 0.64 for $\mathrm{CsSnI_3}$ and $\mathrm{CsPbI_3}$
with scattering time $\tau$=$10^{-14}$ s, and the peak $ZT$ is 0.49 and 0.41
with $\tau$=$10^{-15}$ s. These results make us believe that $\mathrm{CsMI_3}$
(M=Sn and Pb) in perovskite structures may be potential thermoelectric
materials.


title:
Controlling the joint local false discovery rate is more powerful than
  meta-analysis methods in joint analysis of summary statistics from multiple
  genome-wide association studies

abstract:
  In genome-wide association studies (GWASs) of common diseases/traits, we
often analyze multiple GWASs with the same phenotype together to discover
associated genetic variants with higher power. Since it is difficult to access
data with detailed individual measurements, summary-statistics-based
meta-analysis methods have become popular to jointly analyze data sets from
multiple GWASs. In this paper, we propose a novel summary-statistics-based
joint analysis method based on controlling the joint local false discovery rate
(Jlfdr). We prove that our method is the most powerful summary-statistics-based
joint analysis method when controlling the false discovery rate at a certain
level. In particular, the Jlfdr-based method achieves higher power than
commonly used meta-analysis methods when analyzing heterogeneous data sets from
multiple GWASs. Simulation experiments demonstrate the superior power of our
method over meta-analysis methods. Also, our method discovers more associations
than meta-analysis methods from empirical data sets of four phenotypes. The
R-package is available at: http://bioinformatics.ust.hk/Jlfdr.html.


title:
Models Coupling Urban Growth and Transportation Network Growth : An
  Algorithmic Systematic Review Approach

abstract:
  A broad bibliographical study suggests a scarcity of quantitative models of
simulation integrating both network and urban growth. This absence may be due
to diverging interests of concerned disciplines, resulting in a lack of
communication. We propose to proceed to an algorithmic systematic review to
give quantitative elements of answer to this question. A formal iterative
algorithm to retrieve corpuses of references from initial keywords, based on
text-mining, is developed and implemented. We study its convergence properties
and do a sensitivity analysis. We then apply it on queries representative of
the specific question, for which results tend to confirm the assumption of
disciplines compartmentalisation.


title: Building an Evaluation Scale using Item Response Theory

abstract:
  Evaluation of NLP methods requires testing against a previously vetted
gold-standard test set and reporting standard metrics
(accuracy/precision/recall/F1). The current assumption is that all items in a
given test set are equal with regards to difficulty and discriminating power.
We propose Item Response Theory (IRT) from psychometrics as an alternative
means for gold-standard test-set generation and NLP system evaluation. IRT is
able to describe characteristics of individual items - their difficulty and
discriminating power - and can account for these characteristics in its
estimation of human intelligence or ability for an NLP task. In this paper, we
demonstrate IRT by generating a gold-standard test set for Recognizing Textual
Entailment. By collecting a large number of human responses and fitting our IRT
model, we show that our IRT model compares NLP systems with the performance in
a human population and is able to provide more insight into system performance
than standard evaluation metrics. We show that a high accuracy score does not
always imply a high IRT score, which depends on the item characteristics and
the response pattern.


title:
Understanding effects of TCO work function on the performance of organic
  solar cells by numerical simulation

abstract:
  The influences of work function of transparent conducting oxides (TCO) on the
per-formance of organic solar cells, including open circuit voltage, conversion
efficiency and fill factor, has been simulated. It is obtained that for
non-Ohmic contact the open circuit voltage and conversion efficiency increase
monotonically with the TCO work function but keep constant for Ohmic contact.
Fill factor decreases and increases with the electrode work function when the
electrode work function is below and above a critical value (4.2 eV for TCO and
4.5 eV for back-contact), respectively. The results of this simulation are
significant in the choice of TCO contacts to optimize organic planar
heterojunction solar cells.


title:
High-fidelity Rydberg-blockade entangling gate using shaped, analytic
  pulses

abstract:
  We show that the use of shaped pulses improves the fidelity of a Rydberg
blockade two-qubit entangling gate by several orders of magnitude compared to
previous protocols based on square pulses or optimal control pulses. Using
analytical Derivative Removal by Adiabatic Gate (DRAG) pulses that reduce
excitation of primary leakage states and an analytical method of finding the
optimal Rydberg blockade we generate Bell states with a fidelity of $F>0.9999$
in a 300 K environment for a gate time of only $50\;{\rm ns}$, which is an
order of magnitude faster than previous protocols. These results establish the
potential of neutral atom qubits with Rydberg blockade gates for scalable
quantum computation.


title:
Ion velocity distribution functions in argon and helium discharges:
  detailed comparison of numerical simulation results and experimental data

abstract:
  Using Monte Carlo Collisions (MCC) method, we have performed simulations of
ion velocity distribution functions (IVDF) taking into account both elastic
collisions and charge exchange collisions of ions with atoms in uniform
electric fields for argon and helium background gases. The simulation results
are verified by comparison with the experiment data of the ion drift velocities
and the ion transverse diffusion coefficients in argon and helium. The recently
published experimental data for the first seven coefficients of the Legendre
polynomial expansion of the ion energy and angular distribution functions are
used to validate simulation results for IVDF. Good agreements between measured
and simulated IVDFs show that the developed simulation model can be used for
accurate calculations of IVDFs.


title: Saturation and bistability of defect-mode intersubband polaritons

abstract:
  In this article we report about linear and nonlinear optical properties of
intersubband cavity polariton samples, where the resonant photonic mode is a
defect state in a metallo-dielectric photonic crystal slab. By tuning a single
geometric parameter of the resonator, the cavity Q-factor can reach values as
large as 85, with a consequent large cooperativity for the light-matter
interaction. We show that a device featuring large cooperativity leads to sharp
saturation, or even bistability, of the polariton states. This nonlinear
dynamics occurs at the crossover between the weak and the strong coupling
regimes, where the weak critical coupling concept plays a fundamental role.


title:
Trapping neutral particles endowed with a magnetic moment by an
  electromagnetic wave carrying orbital angular momentum: Semiclassical theory

abstract:
  The motion of a neutral atom endowed with a magnetic moment interacting with
the magnetic field is determined from the Ehrenfest-like equations of motion.
These equations for the average values of the translational and spin degrees of
freedom are derived from the Schr\"odinger-Pauli wave equation and they form a
set of nine coupled nonlinear evolution equations. The numerical and analytic
solutions of these equations are obtained for the combination of the rotating
magnetic field of a wave carrying orbital angular momentum and a static
magnetic field. The running wave traps the atom only in the transverse
direction while the standing wave traps the atom also in the direction of the
beam.


title:
Unidirectional superscattering by multilayered cavities of effective
  radial anisotropy

abstract:
  We achieve unidirectional forward superscattering by multilayered spherical
cavities which are effectively radially anisotropic. It is demonstrated that,
relying on the large effective anisotropy, the electric and magnetic dipoles
can be tuned to spectrally overlap in such cavities, which satisfies the
Kerker's condition of simultaneous backward scattering suppression and forward
scattering enhancement. We show such scattering pattern shaping can be obtained
in both all-dielectric and plasmonic multilayered cavities, and believe that
the mechanism we have revealed provides extra freedom for scattering shaping,
which may play a significant role in many scattering related applications and
also in optoelectronic devices made up of intrinsically anisotropic two
dimensional materials.


title: Isgur-Wise function and a new approach to Potential Model

abstract:
  Considering the Cornell potential $V(r)=-\frac{4\alpha_s}{3r}+br+c$, we have
revisited the Dalgarno's method of perturbation by incorporating two scales
$r^{short}$ and $r^{long}$ as integration limit so that the perturbative
procedure can be improved in a potential model. With the improved version of
the wave function the ground state masses of the heavy-light mesons $ D, D_s,
B, B_s$ and $B_c $ are computed. The slopes and curvatures of the form factors
of semi-leptonic decays of heavy-light mesons in both HQET limit and finite
mass limit are calculated and compared with the available data.


title:
Entanglement spectrum of fermionic bilayer honeycomb lattice: Hofstadter
  butterfly

abstract:
  We perform an analytical study of the energy and entanglement spectrum of
non-interacting fermionic bilayer honeycomb lattices in the presence of
trigonal warping in the energy spectrum, on-site energy difference and uniform
magnetic field. Employing single particle correlation functions, we present an
explicit form for layer-layer entanglement Hamiltonian whose spectrum is
entanglement spectrum. We demonstrate that in the absence of trigonal warping,
at zero on-site energy difference exact correspondence is established between
entanglement spectrum and energy spectrum of monolayer which means that the
entanglement spectrum perfectly reflects the edge state properties of the
bilayer. We also show that trigonal warping breaks down such a perfect
correspondence, however, in $\Gamma$-K direction in hexagonal Brillouin zone,
their behaviors are remarkably the same for particular relevances of hopping
parameters. In the presence of an on-site energy difference the symmetry of
entanglement spectrum is broken with opening an indirect entanglement gap. We
also study the effects of a perpendicular magnetic field on both energy and the
entanglement spectrum of the bilayer in the presence of trigonal warping and
on-site energy difference. We demonstrate that the entanglement spectrum versus
magnetic flux has a self similar fractal structure, known Hofstadter butterfly.
Our results also show that the on-site energy difference causes a transition
from the Hofstadter butterfly to a tree-like picture.


title:
Hierarchical low rank approximation of likelihoods for large spatial
  datasets

abstract:
  Datasets in the fields of climate and environment are often very large and
irregularly spaced. To model such datasets, the widely used Gaussian process
models in spatial statis- tics face tremendous challenges due to the
prohibitive computational burden. Various ap- proximation methods have been
introduced to reduce the computational cost. However, most of them rely on
unrealistic assumptions for the underlying process and retaining statistical
efficiency remains an issue. We develop a new approximation scheme for maximum
likeli- hood estimation. We show how the composite likelihood method can be
adapted to provide different types of hierarchical low rank approximations that
are both computationally and statistically efficient. The improvement of the
proposed method is explored theoretically; the performance is investigated by
numerical and simulation studies; and the practicality is illustrated through
applying our methods to 2 million measurements of soil moisture in the area of
the Mississippi River basin, which facilitates a better understanding of the
climate variability.


title: Modelling Trading Networks and the Role of Trust

abstract:
  We present a simple dynamical model for describing trading interactions
between agents in a social network by considering only two dynamical variables,
namely money and goods or services, that are assumed conserved over the whole
time span of the agents' trading transactions. A key feature of the model is
that agent-to-agent transactions are governed by the price in units of money
per goods, which is dynamically changing, and by a trust variable, which is
related to the trading history of each agent. All agents are able to sell or
buy, and the decision to do either has to do with the level of trust the buyer
has in the seller, the price of the goods and the amount of money and goods at
the disposal of the buyer. Here we show the results of extensive numerical
calculations under various initial conditions in a random network of agents and
compare the results with the available related data. In most cases the
agreement between the model results and real data turns out to be fairly good,
which allow us to draw some general conclusions as how different trading
strategies could affect the distribution of wealth in different kinds of
societies.


title: Aspect Level Sentiment Classification with Deep Memory Network

abstract:
  We introduce a deep memory network for aspect level sentiment classification.
Unlike feature-based SVM and sequential neural models such as LSTM, this
approach explicitly captures the importance of each context word when inferring
the sentiment polarity of an aspect. Such importance degree and text
representation are calculated with multiple computational layers, each of which
is a neural attention model over an external memory. Experiments on laptop and
restaurant datasets demonstrate that our approach performs comparable to
state-of-art feature based SVM system, and substantially better than LSTM and
attention-based LSTM architectures. On both datasets we show that multiple
computational layers could improve the performance. Moreover, our approach is
also fast. The deep memory network with 9 layers is 15 times faster than LSTM
with a CPU implementation.


title: Inside black holes with synchronized hair

abstract:
  Recently, various examples of asymptotically flat, rotating black holes (BHs)
with synchronized hair have been explicitly constructed, including Kerr BHs
with scalar or Proca hair, and Myers-Perry BHs with scalar hair and a mass gap,
showing there is a general mechanism at work. All these solutions have been
found numerically, integrating the fully non-linear field equations of motion
from the event horizon outwards. Here, we address the spacetime geometry of
these solutions inside the event horizon. Firstly, we provide arguments, within
linear theory, that there is no regular inner horizon for these solutions.
Then, we address this question fully non-linearly, using as a tractable model
five dimensional, equal spinning, Myers-Perry hairy BHs. We find that, for
non-extremal solutions: $(1)$ the inside spacetime geometry in the vicinity of
the event horizon is smooth and the equations of motion can be integrated
inwards; $(2)$ before an inner horizon is reached, the spacetime curvature
grows (apparently) without bound. In all cases, our results suggest the absence
of a smooth Cauchy horizon, beyond which the metric can be extended, for hairy
BHs with synchronized hair.


title:
A combined model for pseudorapidity distributions in Cu-Cu collisions at
  BNL-RHIC energies

abstract:
  The charged particles produced in nucleus-nucleus collisions come from
leading particles and those frozen out from the hot and dense matter created in
collisions. The leading particles are conventionally supposed having Gaussian
rapidity distributions normalized to the number of participants. The hot and
dense matter is assumed to expand according to the unified hydrodynamics, a
hydro model which unifies the features of Landau and Hwa-Bjorken model, and
freeze out into charged particles from a space-like hypersurface with a proper
time of Tau_FO . The rapidity distribution of this part of charged particles
can be derived out analytically. The combined contribution from both leading
particles and unified hydrodynamics is then compared against the experimental
data performed by BNL-RHIC-PHOBOS Collaboration in different centrality Cu-Cu
collisions at sqrt(s_NN)=200 and 62.4 GeV, respectively. The model predictions
are in well consistent with experimental measurements.


title: On the Dynamics of Rational Maps with Two Free Critical Points

abstract:
  In this paper we discuss the dynamical structure of the rational family
$(f_t)$ given by $$f_t(z)=tz^{m}\Big(\frac{1-z}{1+z}\Big)^{n}\quad(m\ge 2,~t\ne
0).$$ Each map $f_t$ has two super-attracting immediate basins and two free
critical points. We prove that for $0<|t|\le 1$ and $|t|\ge 1$, either of these
basins is completely invariant and at least one of the free critical points is
inactive. Based on this separation we draw a detailed picture the structure of
the dynamical and the parameter plane.


title:
Error functions, Mordell integrals and an integral analogue of partial
  theta function

abstract:
  A new transformation involving the error function $\textup{erf}(z)$, the
imaginary error function $\textup{erfi}(z)$, and an integral analogue of a
partial theta function is given along with its character analogues. Another
complementary error function transformation is also obtained which when
combined with the first explains a transformation in Ramanujan's Lost Notebook
termed by Berndt and Xu as the one for an integral analogue of theta functions.
These transformations are used to obtain a variety of exact and approximate
evaluations of some non-elementary integrals involving hypergeometric
functions. Several asymptotic expansions, including the one for a
non-elementary integral involving a product of the Riemann $\Xi$-function of
two different arguments, are obtained, which generalize known results due to
Berndt and Evans, and Oloa.


title: A Study of $k$-dipath Colourings of Oriented Graphs

abstract:
  We examine $t$-colourings of oriented graphs in which, for a fixed integer $k
\geq 1$, vertices joined by a directed path of length at most $k$ must be
assigned different colours. A homomorphism model that extends the ideas of
Sherk for the case $k=2$ is described. Dichotomy theorems for the complexity of
the problem of deciding, for fixed $k$ and $t$, whether there exists such a
$t$-colouring are proved.


title:
Perfect energy-feeding into strongly coupled systems and interferometric
  control of polariton absorption

abstract:
  The ability to feed energy into a system, or - equivalently - to drive that
system with an external input is a fundamental aspect of light-matter
interaction. The key concept in many photonic applications is the "critical
coupling" condition: at criticality, all the energy fed to the system via an
input channel is dissipated within the system itself. Although this idea was
crucial to enhance the efficiency of many devices, it was never considered in
the context of systems operating in a non-perturbative regime. In this
so-called strong coupling regime, the matter and light degrees of freedom are
in fact mixed into dressed states, leading to new eigenstates called
polaritons. Here we demonstrate that the strong coupling regime and the
critical coupling condition can indeed coexist; in this situation, which we
term strong critical coupling, all the incoming energy is converted into
polaritons. A semiclassical theory - equivalently applicable to acoustics or
mechanics - reveals that the strong critical coupling corresponds to a special
curve in the phase diagram of the coupled light-matter oscillators. In the more
general case of a system radiating via two scattering ports, the phenomenology
displayed is that of coherent perfect absorption (CPA), which is then naturally
understood and described in the framework of critical coupling. Most
importantly, we experimentally verify polaritonic CPA in a semiconductor-based
intersubband-polariton photonic-crystal membrane resonator. This result opens
new avenues in the exploration of polariton physics, making it possible to
control the pumping efficiency of a system almost independently of its Rabi
energy, i.e., of the energy exchange rate between the electromagnetic field and
the material transition.


title: A Census of Young Stars and Brown Dwarfs in IC 348 and NGC 1333

abstract:
  We have obtained optical and near-infrared spectra of candidate members of
the star-forming clusters IC 348 and NGC 1333. We classify 100 and 42
candidates as new members of the clusters, respectively, which brings the total
numbers of known members to 478 and 203. We also have performed spectroscopy on
a large majority of the previously known members of NGC 1333 in order to
provide spectral classifications that are measured with the same scheme that
has been applied to IC 348 in previous studies. The new census of members is
nearly complete for Ks<16.8 at Aj<1.5 in IC 348 and for Ks<16.2 at Aj<3 in NGC
1333, which correspond to masses of <=0.01 Msun for ages of 3 Myr according to
theoretical evolutionary models. The faintest known members extend below these
completeness limits and appear to have masses of ~0.005 Msun. In
extinction-limited samples of cluster members, NGC 1333 exhibits a higher
abundance of objects at lower masses than IC 348. It would be surprising if the
initial mass functions of these clusters differ significantly given their
similar stellar densities and formation environments. Instead, it is possible
that average extinctions are lower for less massive members of star-forming
clusters, in which case extinction-limited samples could be biased in favor of
low-mass objects in the more heavily embedded clusters like NGC 1333. In the
H-R diagram, the median sequences of IC 348 and NGC 1333 coincide with each
other for the adopted distances of 300 and 235 pc, which would suggest that
they have similar ages. However, NGC 1333 is widely believed to be younger than
IC 348 based on its higher abundance of disks and protostars and its greater
obscuration. Errors in the adopted distances may be responsible for this
discrepancy.


title:
What does past correlation structure tell us about the future? An answer
  from network filtering

abstract:
  We discovered that past changes in the market correlation structure are
significantly related with future changes in the market volatility. By using
correlation-based information filtering networks we device a new tool for
forecasting the market volatility changes. In particular, we introduce a new
measure, the "correlation structure persistence", that quantifies the rate of
change of the market dependence structure. This measure shows a deep interplay
with changes in volatility and we demonstrate it can anticipate market risk
variations. Notably, our method overcomes the curse of dimensionality that
limits the applicability of traditional econometric tools to portfolios made of
a large number of assets. We report on forecasting performances and statistical
significance of this tool for two different equity datasets. We also identify
an optimal region of parameters in terms of True Positive and False Positive
trade-off, through a ROC curve analysis. We find that our forecasting method is
robust and it outperforms predictors based on past volatility only. Moreover
the temporal analysis indicates that our method is able to adapt to abrupt
changes in the market, such as financial crises, more rapidly than methods
based on past volatility.


title:
Response statistics dissect the contributions of different sources of
  variability to population activity in V1

abstract:
  Response variability, as measured by fluctuating responses upon repeated
performance of trials, is a major component of neural responses, and its
characterization is key to interpret high dimensional population recordings.
Response variability and covariability display predictable changes upon changes
in stimulus and cognitive or behavioral state, providing an opportunity to test
the predictive power of models of neural variability. Still, there is little
agreement on which model to use as a building block for population-level
analyses, and models of variability are often treated as a subject of choice.
We investigate two competing models, the Doubly Stochastic Poisson (DSP) model
assuming stochasticity at spike generation, and the Rectified Gaussian (RG)
model that traces variability back to membrane potential variance, to analyze
stimulus-dependent modulation of response statistics. Using a model of a pair
of neurons, we demonstrate that the two models predict similar single-cell
statistics. However, DSP and RG models have contradicting predictions on the
joint statistics of spiking responses. In order to test the models against
data, we build a population model to simulate stimulus change-related
modulations in response statistics. We use unit recordings from the primary
visual cortex of monkeys to show that while model predictions for variance are
qualitatively similar to experimental data, only the RG model's predictions are
compatible with joint statistics. These results suggest that models using
Poisson-like variability might fail to capture important properties of response
statistics. We argue that membrane potential-level modelling of stochasticity
provides an efficient strategy to model correlations.


title: The A-Cycle Problem for Transverse Ising Ring

abstract:
  Traditionally, the transverse Ising model is mapped to the fermionic c-cycle
problem, which neglects the boundary effect due to thermodynamic limit. If
persisting on a perfect periodic boundary condition, we can get a so-called
a-cycle problem that has not been treated seriously so far (Lieb et al., 1961
\textit{Ann. of Phys.} \textbf{16} 407). In this work, we show a little
surprising but exact result in this respect. We find the odevity of the number
of lattice sites, $N$, in the a-cycle problem plays an unexpected role even in
the thermodynamic limit, $N\rightarrow\infty$, due to the boundary constraint.
We pay a special attention to the system with $N(\in Odd)\rightarrow\infty$,
which is in contrast to the one with $N(\in Even)\rightarrow\infty$, because
the former suffers a ring frustration. As a new effect, we find the ring
frustration induces a low-energy gapless spectrum above the ground state. By
proving a theorem for a new type of Toeplitz determinant, we demonstrate that
the ground state in the gapless region exhibits a peculiar longitudinal
spin-spin correlation. The entangled nature of the ground state is also
disclosed by the evaluation of its entanglement entropy. At low temperatures,
new behavior of specific heat is predicted. We also propose an experimental
protocol for observing the new phenomenon due to the ring frustration.


title: A geometric characterisation of toric varieties

abstract:
  We prove a conjecture of Shokurov which characterises toric varieties using
log pairs.


title:
A Riemannian Framework for Statistical Analysis of Topological
  Persistence Diagrams

abstract:
  Topological data analysis is becoming a popular way to study high dimensional
feature spaces without any contextual clues or assumptions. This paper concerns
itself with one popular topological feature, which is the number of
$d-$dimensional holes in the dataset, also known as the Betti$-d$ number. The
persistence of the Betti numbers over various scales is encoded into a
persistence diagram (PD), which indicates the birth and death times of these
holes as scale varies. A common way to compare PDs is by a point-to-point
matching, which is given by the $n$-Wasserstein metric. However, a big drawback
of this approach is the need to solve correspondence between points before
computing the distance; for $n$ points, the complexity grows according to
$\mathcal{O}($n$^3)$. Instead, we propose to use an entirely new framework
built on Riemannian geometry, that models PDs as 2D probability density
functions that are represented in the square-root framework on a Hilbert
Sphere. The resulting space is much more intuitive with closed form expressions
for common operations. The distance metric is 1) correspondence-free and also
2) independent of the number of points in the dataset. The complexity of
computing distance between PDs now grows according to $\mathcal{O}(K^2)$, for a
$K \times K$ discretization of $[0,1]^2$. This also enables the use of existing
machinery in differential geometry towards statistical analysis of PDs such as
computing the mean, geodesics, classification etc. We report competitive
results with the Wasserstein metric, at a much lower computational load,
indicating the favorable properties of the proposed approach.

categories: math.AT cs.CG cs.CV math.DG math.ST stat.TH


title:
Bipartite qutrit local realist inequalities and the robustness of their
  quantum mechanical violation

abstract:
  Distinct from the type of local realist inequality (known as the
Collins-Gisin-Linden-Massar-Popescu or CGLMP inequality) usually used for
bipartite qutrit systems, we formulate a new set of local realist inequalities
for bipartite qutrits by generalizing Wigner's argument that was originally
formulated for the bipartite qubit singlet state. This treatment assumes
existence of the overall joint probability distributions in the underlying
stochastic hidden variable space for the measurement outcomes pertaining to the
relevant trichotomic observables, satisfying the locality condition and
yielding the measurable marginal probabilities. Such generalized Wigner
inequalities (GWI) do not reduce to Bell-CHSH type inequalities by clubbing any
two outcomes, and are violated by quantum mechanics (QM) for both the bipartite
qutrit isotropic and singlet states using trichotomic observables defined by
six-port beam splitter as well as by the spin-$1$ component observables. The
efficacy of GWI is then probed in these cases by comparing the QM violation of
GWI with that obtained for the CGLMP inequality. This comparison is done by
incorporating white noise in the singlet and isotropic qutrit states. It is
found that for the six-port beam splitter observables, QM violation of GWI is
more robust than that of the CGLMP inequality for singlet qutrit states, while
for isotropic qutrit states, QM violation of the CGLMP inequality is more
robust. On the other hand, for the spin-$1$ component observables, QM violation
of GWI is more robust for both the type of states considered.


title:
Effects of $c/a$ Anisotropy and Local Crystal Structure on
  Superconductivity in
  $A\mathrm{Fe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$
  ($A$=Ba$_{1-y}$Sr$_y$, Sr$_{1-y}$Ca$_y$ and Eu)

abstract:
  We investigated the effects of $c/a$ anisotropy and local crystal structure
on superconductivity (SC) in As/P solid solution systems,
$A\mathrm{Fe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$ ($A$122P) with
various $A$ ions. With decreasing $A$ site atomic size from $A$=Ba to Eu, the
structural anisotropy decreases, and the rate of decreasing with $x$ also
increases. The rapid narrowing of the region of antiferromagnetic composition
($x$) can be considered to be a result of this anisotropy change due mainly to
the change in the Fermi surface (FS) nesting condition. By contrast, although
the structural anisotropy systematically changes, the maximum $T_{\mathrm{c}}$
values are almost the same in all $A$122P systems except for Eu122P. These
results indicate that the modification of the FS topology via the structural
anisotropy does not affect SC. However local structural parameters, such as
pnictogen height, are crucial for $T_{\mathrm{c}}$.


title: Dark spots along slowly scaling chains of plasmonic nanoparticles

abstract:
  We numerically investigate the optical response of slowly scaling linear
chains of mismatched silver nanoparticles. Hybridized plasmon chain resonances
manifest unusual local field distributions around the nanoparticles that result
from symmetry breaking of the geometry. Importantly, we find localization
patterns characterized by bright hot-spots alternated by what we term
\textit{dark} spots. A dark spot is associated to dark plasmons that have
collinear and antiparallel dipole moments along the chain. As a result, the
field amplification in the dark interjunction gap is extinguished for incident
polarization parallel to the chain axis. Despite the strong plasmonic coupling,
the nanoparticles on the sides of this dark gap experience a dramatic
asymmetric field amplification with amplitude gain contrast $> 2 \times 10^2$.
Remarkably, also for polarization orthogonal to the axis, gap hot-spots form on
resonance.


title: Alpha decay as a probe for the structure of neutron-deficient nuclei

abstract:
  The advent of radioactive ion beam facilities and new detector technologies
have opened up new possibilities to investigate the radioactive decays of
highly unstable nuclei, in particular the proton emission, $\alpha$ decay and
heavy cluster decays from neutron-deficient (or proton-rich) nuclei around the
proton drip line. It turns out that these decay measurements can serve as a
unique probe for studying the structure of the nuclei involved. On the
theoretical side, the development in nuclear many-body theories and
supercomputing facilities have also made it possible to simulate the nuclear
clusterization and decays from a microscopic and consistent perspective. In
this article we would like to review the current status of these structure and
decay studies in heavy nuclei, regarding both experimental and theoretical
opportunities. We then discuss in detail the recent progress in our
understanding of the nuclear $\alpha$ formation probabilities in heavy nuclei
and their indication on the underlying nuclear structure.


title:
Molecular Emission in Dense Massive Clumps from the Star-Forming Regions
  S231-S235

abstract:
  The article deals with observations of star-forming regions S231-S235 in
'quasi-thermal' lines of ammonia (NH$_3$), cyanoacetylene (HC$_3$N) and maser
lines of methanol (CH$_3$OH) and water vapor (H$_2$O). S231-S235 regions is
situated in the giant molecular cloud G174+2.5. We selected all massive
molecular clumps in G174+2.5 using archive CO data. For the each clump we
determined mass, size and CO column density. After that we performed
observations of these clumps. We report about first detections of NH$_3$ and
HC$_3$N lines toward the molecular clumps WB89 673 and WB89 668. This means
that high-density gas is present there. Physical parameters of molecular gas in
the clumps were estimated using the data on ammonia emission. We found that the
gas temperature and the hydrogen number density are in the ranges 16-30 K and
2.8-7.2$\times10^3$ cm$^{-3}$, respectively. The shock-tracing line of CH$_3$OH
molecule at 36.2 GHz is newly detected toward WB89 673.


title:
Hubbard interactions in iron-based pnictides and chalcogenides: Slater
  parametrization, screening channels and frequency dependence

abstract:
  We calculate the strength of the frequency-dependent on-site electronic
interactions in the iron pnictides LaFeAsO, BaFe2As2, BaRu2As2, and LiFeAs and
the chalcogenide FeSe from first principles within the constrained random phase
approximation. We discuss the accuracy of an atomic-like parametrization of the
two-index density-density interaction matrices based on the calculation of an
optimal set of three independent Slater integrals, assuming that the angular
part of the Fe-d localized orbitals can be described within spherical harmonics
as for isolated Fe atoms. We show that its quality depends on the ligand-metal
bonding character rather than on the dimensionality of the lattice: it is
excellent for ionic-like Fe-Se (FeSe) chalcogenides and a more severe
approximation for more covalent Fe-As (LaFeAsO, BaFe2As2) pnictides. We
furthermore analyze the relative importance of different screening channels,
with similar conclusions for the different pnictides but a somewhat different
picture for the benchmark oxide SrVO3: the ligand channel does not appear to be
dominant in the pnictides, while oxygen screening is the most important process
in the oxide. Finally, we analyze the frequency dependence of the interaction.
In contrast to simple oxides, in iron pnictides its functional form cannot be
simply modeled by a single plasmon, and the actual density of modes enters the
construction of an effective Hamiltonian determining the low-energy properties.


title: Constructing Mutually Unbiased Bases from Quantum Latin Squares

abstract:
  We introduce orthogonal quantum Latin squares, which restrict to traditional
orthogonal Latin squares, and investigate their application in quantum
information science. We use quantum Latin squares to build maximally entangled
bases, and show how a pair of mutually unbiased maximally entangled bases can
be constructed in square dimension from orthogonal quantum Latin squares. We
also compare our construction to an existing construction due to Beth and
Wocjan and show that ours is strictly more general.


title: Odd-even staggering in neutron drip line nuclei

abstract:
  We have done systematic Hartree-Fock-Bogoliubov calculations in coordinate
space on the one-quasi-particle energies and binding energy odd-even staggering
(OES) in semi-magic nuclei with the zero-range volume, mixed and surface
pairing forces in order to explore the influence of their density dependence.
The odd-$N$ isotopes are calculated within the blocking scheme. The strengths
for the pairing forces are determined in two schemes by fitting locally to
reproduce pairing gap in $^{120}$Sn and globally to all available data on the
OES of semi-magic nuclei with $Z\geq8$. In the former calculations, there is a
noticeable difference between the neutron mean gaps in neutron-rich O, Ca, Ni
and Sn isotopes calculated with the surface pairing and those with the mixed
and volume pairing.
  The difference gets much smaller if the globally optimized pairing strengths
are employed. The heavier Pb isotopes show the opposite trend. Moreover, large
differences between the mean gap and the OES may be expected in both
calculations when one goes towards the neutron drip line.


title: Nanofiber-segment ring resonator

abstract:
  We describe a fiber ring resonator comprised of a relatively long loop of
standard single-mode fiber with a short nanofiber segment. The evanescent mode
of the nanofiber segment allows the cavity-enhanced field to interact with
atoms in close proximity to the nanofiber surface. We report on an experiment
using a warm atomic vapor and low-finesse cavity, and briefly discuss the
potential for reaching the strong coupling regime of cavity QED by using
trapped atoms and a high-finesse cavity of this kind.


title: Quantum phase space measurement and entanglement validation made easy

abstract:
  It has recently been shown that it is possible to represent the complete
quantum state of any system as a phase-space quasi-probability distribution
(Wigner function) [Phys Rev Lett 117, 180401]. Such functions take the form of
expectation values of an observable that has a direct analogy to displaced
parity operators. In this work we give a procedure for the measurement of the
Wigner function that should be applicable to any quantum system. We have
applied our procedure to IBM's Quantum Experience five-qubit quantum processor
to demonstrate that we can measure and generate the Wigner functions of two
different Bell states as well as the five-qubit Greenberger-Horne-Zeilinger
(GHZ) state. As Wigner functions for spin systems are not unique, we define,
compare, and contrast two distinct examples. We show how using these Wigner
functions leads to an optimal method for quantum state analysis especially in
the situation where specific characteristic features are of particular interest
(such as for spin Schr\"odinger cat states). Furthermore we show that this
analysis leads to straightforward, and potentially very efficient, entanglement
test and state characterisation methods.


title:
The Higgs Boson Mass from Three-loop Effective Potential of Massless
  Standard Model

abstract:
  The effective potential of massless standard model (SM) is calculated up to
three-loop order. The stability of the effective potential and the Higgs boson
mass are investigated up to three-loop order. We found that, Higgs boson mass
$m_{H}$ of one-loop order is large. The two-loop and three-loop results are not
appreciably different from each other. The two-loop and three-loop radiative
corrections have led to an improvement of Higgs boson mass and the value of the
scalar coupling. For the value $m_{t}=170$ GeV at the energy scale $\mu\approx
5.68\times10^2$GeV, we get $m_{H2-loop}\approx 125.4$ GeV. At the energy scale
$\mu\geq28\times10^2$, the scalar coupling $\lambda$ at two-loop becomes
negative and leads to metastable vacuum while the three-loop level is stable
even at high $\mu$ $\approx 10^{19}$ GeV. For the larger $\mu$-range $(3 \times
10^{3} \text{GeV}\leq \mu \leq 20 \times 10^{3} \text{GeV})$ spontaneous
symmetry breaking for one-loop and three-loop occurs at approximately the same
scalar coupling values. We get $m_{H1-loop}\approx 126.14$ GeV at $\mu \approx
6.5 \times 10^{3}$ GeV while for three-loop $m_{H3-loop}\approx 126$ GeV at
$\mu \approx 20 \times 10^{3}$ GeV.


title:
Cyclic Density Functional Theory : A route to the first principles
  simulation of bending in nanostructures

abstract:
  We formulate and implement Cyclic Density Functional Theory (Cyclic DFT) -- a
self-consistent first principles simulation method for nanostructures with
cyclic symmetries. Using arguments based on Group Representation Theory, we
rigorously demonstrate that the Kohn-Sham eigenvalue problem for such systems
can be reduced to a fundamental domain (or cyclic unit cell) augmented with
cyclic-Bloch boundary conditions. Analogously, the equations of electrostatics
appearing in Kohn-Sham theory can be reduced to the fundamental domain
augmented with cyclic boundary conditions. By making use of this symmetry cell
reduction, we show that the electronic ground-state energy and the
Hellmann-Feynman forces on the atoms can be calculated using quantities defined
over the fundamental domain. We develop a symmetry-adapted finite-difference
discretization scheme to obtain a fully functional numerical realization of the
proposed approach. We verify that our formulation and implementation of Cyclic
DFT is both accurate and efficient through selected examples.
  The connection of cyclic symmetries with uniform bending deformations
provides an elegant route to the ab-initio study of bending in nanostructures
using Cyclic DFT. As a demonstration of this capability, we simulate the
uniform bending of a silicene nanoribbon and obtain its energy-curvature
relationship from first principles. A self-consistent ab-initio simulation of
this nature is unprecedented and well outside the scope of any other systematic
first principles method in existence. Our simulations reveal that the bending
stiffness of the silicene nanoribbon is intermediate between that of graphene
and molybdenum disulphide. We describe several future avenues and applications
of Cyclic DFT, including its extension to the study of non-uniform bending
deformations and its possible use in the study of the nanoscale flexoelectric
effect.


title:
Vibrational mean free paths and thermal conductivity of amorphous
  silicon from non-equilibrium molecular dynamics simulations

abstract:
  The frequency-dependent mean free paths (MFPs) of vibrational heat carriers
in amorphous silicon are predicted from the length dependence of the spectrally
decomposed heat current (SDHC) obtained from non-equilibrium molecular dynamics
simulations. The results suggest a (frequency)$^{-2}$ scaling of the
room-temperature MFPs below 5 THz. The MFPs exhibit a local maximum at a
frequency of 8 THz and fall below 1 nm at frequencies greater than 10 THz,
indicating localized vibrations. The MFPs extracted from sub-10 nm system-size
simulations are used to predict the length-dependence of thermal conductivity
up to system sizes of 100 nm and good agreement is found with separate
molecular dynamics simulations. Weighting the SDHC by the frequency-dependent
quantum occupation function provides a simple and convenient method to account
for quantum statistics and provides reasonable agreement with the
experimentally-measured trend and magnitude.


title:
Decentralized Control via Dynamic Stochastic Prices: The Independent
  System Operator Problem

abstract:
  A smart grid connects wind or solar or storage farms, fossil fuel plants,
industrialor commercial loads, or load serving entities, modeled as stochastic
dynamical systems. In each time period, they consume or supply electrical
energy, with the constraint that total generation equals consumption. Each
agent's utility is either the benefit accrued from consumption, or negative of
generation cost. The Independent System Operator has to maximize their sum, the
social welfare, without agents revealing their dynamic models or utilities. It
has to announce prices after interacting with agents via bids.
  If agents observe and know the laws of uncertainties affecting other agents,
then there is an iterative price and bid interaction that leads to the maximum
social welfare attainable if agents pooled their information.
  In the important case where agents are LQG systems not even knowing of the
existence of other agents, the bid and price iteration is dramatically simple,
exchanging time vectors of future prices and consumptions or generations at
each time step. State dependent bidding is not needed. This solution of the
decentralized stochastic control problem may be of economic importance in power
systems, and of broader interest in general equilibrium theory of economics for
stochastic dynamic agents.