title:
Prediction of a Two-dimensional Sulfur Nitride (S3N2) Solid for
  Nanoscale Optoelectronic Applications

abstract:
  Two-dimensional materials have attracted tremendous attention for their
fascinating electronic, optical, chemical and mechanical properties. However,
the band gaps of most 2D materials reported are smaller than 2.0 eV, which
greatly restricted their optoelectronic applications in blue and ultraviolet
range of the spectrum. Here, we propose a new stable sulfur nitride (S3N2) 2D
crystal that is a covalent network composed solely of S-N {\sigma} bonds. S3N2
crystal is dynamically stable as confirmed by the computed phonon spectrum and
ab initio molecular dynamics simulations in the NPT ensemble. Hybrid density
functional calculations show that 2D S3N2 crystal is a wide, direct band-gap
(3.17 eV) semiconductor with good hole mobility. These fascinating electronic
properties could pave the way for its optoelectronic applications such as blue
or ultra-violet light-emitting diodes (LEDs) and photodetectors.


title:
Energy loss of a nonaccelerating quark moving through a strongly coupled
  N=4 super Yang-Mills vacuum or plasma in strong magnetic field

abstract:
  Using AdS/CFT correspondence, we find that a massless quark moving at the
speed of light $v=1$, in arbitrary direction, through a strongly coupled
$\mathcal{N}=4$ super Yang-Mills (SYM) vacuum at $T=0$, in the presence of
strong magnetic field $\mathcal{B}$, loses its energy at a rate linearly
dependent on $\mathcal{B}$, i.e.,
$\frac{dE}{dt}=-\frac{\sqrt{\lambda}}{6\pi}\mathcal{B}$. We also show that a
heavy quark of mass $M\neq 0$ moving at near the speed of light
$v^2=v_{*}^2=1-\frac{4\pi^2 T^2}{\mathcal{B}}\simeq1$, in arbitrary direction,
through a strongly coupled $\mathcal{N}=4$ SYM plasma at finite temperature
$T\neq 0$, in the presence of strong magnetic field $\mathcal{B}\gg T^2$, loses
its energy at a rate linearly dependent on $\mathcal{B}$, i.e.,
$\frac{dE}{dt}=-\frac{\sqrt{\lambda}}{6\pi}\mathcal{B}v_{*}^2\simeq-\frac{\sqrt{\lambda}}{6\pi}\mathcal{B}$.
Moreover, we argue that, in the strong magnetic field $\mathcal{B}\gg T^2$ (IR)
regime, $\mathcal{N}=4$ SYM and adjoint QCD theories (when the adjoint QCD
theory has four flavors of Weyl fermions and is at its conformal IR fixed point
$\lambda=\lambda^*$) have the same microscopic degrees of freedom (i.e., gluons
and lowest Landau levels of Weyl fermions) even though they have quite
different microscopic degrees of freedom in the UV when we consider higher
Landau levels. Therefore, in the strong magnetic field $\mathcal{B}\gg T^2$
(IR) regime, the thermodynamic and hydrodynamic properties of $\mathcal{N}=4$
SYM and adjoint QCD plasmas, as well as the rates of energy loss of a quark
moving through the plasmas, should be the same.


title:
Effect of Densification on Cellular Network Performance with Bounded
  Pathloss Model

abstract:
  In this paper, we investigate how network densification influences the
performance of downlink cellular network in terms of coverage probability (CP)
and area spectral efficiency (ASE). Instead of the simplified unbounded
pathloss model (UPM), we apply a more realistic bounded pathloss model (BPM) to
model the decay of signal power caused by pathloss. It is shown that network
densification indeed degrades CP when the base station (BS) density $\lambda$
is sufficiently large. This is inconsistent with the result derived using UPM
that CP is independent of $\lambda$. Moreover, we shed light on the impact of
ultra-dense deployment of BSs on the ASE scaling law. Specifically, it is
proved that the cellular network ASE scales with rate $\lambda
e^{-\kappa\lambda}$, i.e., first increases with $\lambda$ and then diminishes
to be zero as $\lambda$ goes to infinity.


title: Attainable numbers and the Lagrange spectrum

abstract:
  The paper is devoted to the properties of the Lagrange spectrum left
endpoints and so-called attainable numbers.


title: shapeDTW: shape Dynamic Time Warping

abstract:
  Dynamic Time Warping (DTW) is an algorithm to align temporal sequences with
possible local non-linear distortions, and has been widely applied to audio,
video and graphics data alignments. DTW is essentially a point-to-point
matching method under some boundary and temporal consistency constraints.
Although DTW obtains a global optimal solution, it does not necessarily achieve
locally sensible matchings. Concretely, two temporal points with entirely
dissimilar local structures may be matched by DTW. To address this problem, we
propose an improved alignment algorithm, named shape Dynamic Time Warping
(shapeDTW), which enhances DTW by taking point-wise local structural
information into consideration. shapeDTW is inherently a DTW algorithm, but
additionally attempts to pair locally similar structures and to avoid matching
points with distinct neighborhood structures. We apply shapeDTW to align audio
signal pairs having ground-truth alignments, as well as artificially simulated
pairs of aligned sequences, and obtain quantitatively much lower alignment
errors than DTW and its two variants. When shapeDTW is used as a distance
measure in a nearest neighbor classifier (NN-shapeDTW) to classify time series,
it beats DTW on 64 out of 84 UCR time series datasets, with significantly
improved classification accuracies. By using a properly designed local
structure descriptor, shapeDTW improves accuracies by more than 10% on 18
datasets. To the best of our knowledge, shapeDTW is the first distance measure
under the nearest neighbor classifier scheme to significantly outperform DTW,
which had been widely recognized as the best distance measure to date. Our code
is publicly accessible at: https://github.com/jiapingz/shapeDTW.


title:
A new device-independent dimension witness and its experimental
  implementation

abstract:
  A dimension witness is a criterion that sets a lower bound on the dimension
needed to reproduce the observed data. Three types of dimension witnesses can
be found in the literature: device-dependent ones, in which the bound is
obtained assuming some knowledge on the state and the measurements;
device-independent prepare-and-measure ones, that can be applied to any system
including classical ones; and device-independent Bell-based ones, that certify
the minimal dimension of some entangled systems. Here we consider the
Collins-Gisin-Linden-Massar-Popescu (CGLMP) Bell-type inequality for four
outcomes. We show that a sufficiently high violation of this inequality
witnesses $d \geq 4$ and present a proof-of-principle experimental observation
of such a violation. This presents a first experimental violation of the third
type of dimension witness beyond qutrits.


title:
Generating and Exploiting Large-scale Pseudo Training Data for Zero
  Pronoun Resolution

abstract:
  Most existing approaches for zero pronoun resolution are heavily relying on
annotated data, which is often released by shared task organizers. Therefore,
the lack of annotated data becomes a major obstacle in the progress of zero
pronoun resolution task. Also, it is expensive to spend manpower on labeling
the data for better performance. To alleviate the problem above, in this paper,
we propose a simple but novel approach to automatically generate large-scale
pseudo training data for zero pronoun resolution. Furthermore, we successfully
transfer the cloze-style reading comprehension neural network model into zero
pronoun resolution task and propose a two-step training mechanism to overcome
the gap between the pseudo training data and the real one. Experimental results
show that the proposed approach significantly outperforms the state-of-the-art
systems with an absolute improvements of 3.1% F-score on OntoNotes 5.0 data.


title:
Orthogonality of the mean and error distribution in generalized linear
  models

abstract:
  We show that the mean-model parameter is always orthogonal to the error
distribution in generalized linear models. Thus, the maximum likelihood
estimator of the mean-model parameter will be asymptotically efficient
regardless of whether the error distribution is known completely, known up to a
finite vector of parameters, or left completely unspecified, in which case the
likelihood is taken to be an appropriate semiparametric likelihood. Moreover,
the maximum likelihood estimator of the mean-model parameter will be
asymptotically independent of the maximum likelihood estimator of the error
distribution. This generalizes some well-known results for the special cases of
normal, gamma and multinomial regression models, and, perhaps more
interestingly, suggests that asymptotically efficient estimation and inferences
can always be obtained if the error distribution is nonparametrically estimated
along with the mean. In contrast, estimation and inferences using misspecified
error distributions or variance functions are generally not efficient.


title:
Note on the index conjecture in zero-sum theory and its connection to a
  Dedekind-type sum

abstract:
  Let $S=(a_1)\cdots(a_k)$ be a minimal zero-sum sequence over a finite cyclic
group $G$. The index conjecture states that if $k=4$ and $\gcd(|G|,6)=1$, then
$S$ has index 1. In this note we study the index conjecture and connect it to a
Dedekind-type sum. In particular we reprove a special case of the conjecture
when $|G|$ is prime.


title:
Improved energy confinement with nonlinear isotope effects in
  magnetically confined plasmas

abstract:
  The efficient production of electricity from nuclear fusion in magnetically
confined plasmas relies on a good confinement of the thermal energy. For more
than thirty years, the observation that such confinement depends on the mass of
the plasma isotope and its interaction with apparently unrelated plasma
conditions has remained largely unexplained and it has become one of the main
unsolved issues. By means of numerical studies based on the gyrokinetic theory,
we quantitatively show how the plasma microturbulence depends on the isotope
mass through nonlinear multiscale microturbulence effects involving the
interplay between zonal flows, electromagnetic effects and the torque applied.
This finding has crucial consequences for the design of future reactors since,
in spite of the fact that they will be composed by multiple ion species, their
extrapolation from present day experiments heavily relies on the knowledge
obtained from a long experimental tradition based in single isotope plasmas.


title: CG-OoO: Energy-Efficient Coarse-Grain Out-of-Order Execution

abstract:
  We introduce the Coarse-Grain Out-of-Order (CG- OoO) general purpose
processor designed to achieve close to In-Order processor energy while
maintaining Out-of-Order (OoO) performance. CG-OoO is an energy-performance
proportional general purpose architecture that scales according to the program
load. Block-level code processing is at the heart of the this architecture;
CG-OoO speculates, fetches, schedules, and commits code at block-level
granularity. It eliminates unnecessary accesses to energy consuming tables, and
turns large tables into smaller and distributed tables that are cheaper to
access. CG-OoO leverages compiler-level code optimizations to deliver efficient
static code, and exploits dynamic instruction-level parallelism and block-level
parallelism. CG-OoO introduces Skipahead issue, a complexity effective, limited
out-of-order instruction scheduling model. Through the energy efficiency
techniques applied to the compiler and processor pipeline stages, CG-OoO closes
64% of the average energy gap between the In-Order and Out-of-Order baseline
processors at the performance of the OoO baseline. This makes CG-OoO 1.9x more
efficient than the OoO on the energy-delay product inverse metric.


title:
Throughput Optimal Decentralized Scheduling of Multi-Hop Networks with
  End-to-End Deadline Constraints: Unreliable Links

abstract:
  We consider unreliable multi-hop networks serving multiple flows in which
packets not delivered to their destination nodes by their deadlines are
dropped. We address the design of policies for routing and scheduling packets
that optimize any specified weighted average of the throughputs of the flows.
We provide a new approach which directly yields an optimal distributed
scheduling policy that attains any desired maximal timely-throughput vector
under average-power constraints on the nodes. It pursues a novel intrinsically
stochastic decomposition of the Lagrangian of the constrained network-wide MDP
rather than of the fluid model. All decisions regarding a packet's transmission
scheduling, transmit power level, and routing, are completely distributed,
based solely on the age of the packet, not requiring any knowledge of network
state or queue lengths at any of the nodes. Global coordination is achieved
through a tractably computable "price" for transmission energy. This price is
different from that used to derive the backpressure policy where price
corresponds to queue lengths. A quantifiably near-optimal policy is provided if
nodes have peak-power constraints.


title:
Deep Recurrent Convolutional Networks for Video-based Person
  Re-identification: An End-to-End Approach

abstract:
  In this paper, we present an end-to-end approach to simultaneously learn
spatio-temporal features and corresponding similarity metric for video-based
person re-identification. Given the video sequence of a person, features from
each frame that are extracted from all levels of a deep convolutional network
can preserve a higher spatial resolution from which we can model finer motion
patterns. These low-level visual percepts are leveraged into a variant of
recurrent model to characterize the temporal variation between time-steps.
Features from all time-steps are then summarized using temporal pooling to
produce an overall feature representation for the complete sequence. The deep
convolutional network, recurrent layer, and the temporal pooling are jointly
trained to extract comparable hidden-unit representations from input pair of
time series to compute their corresponding similarity value. The proposed
framework combines time series modeling and metric learning to jointly learn
relevant features and a good similarity measure between time sequences of
person.
  Experiments demonstrate that our approach achieves the state-of-the-art
performance for video-based person re-identification on iLIDS-VID and PRID
2011, the two primary public datasets for this purpose.


title: Optimal Auctions with Restricted Allocations

abstract:
  We study the problem of designing optimal auctions under restrictions on the
set of permissible allocations. In addition to allowing us to restrict to
deterministic mechanisms, we can also indirectly model non-additive valuations.
We prove a strong duality result, extending a result due to Daskalakis et al.
[2015], that guarantees the existence of a certificate of optimality for
optimal restricted mechanisms. As a corollary of our result, we provide a new
characterization of the set of allocations that the optimal mechanism may
actually use. To illustrate our result we find and certify optimal mechanisms
for four settings where previous frameworks do not apply, and provide new
economic intuition about some of the tools that have previously been used to
find optimal mechanisms.


title: Divisors computing the minimal log discrepancy on a smooth surface

abstract:
  We study a divisor computing the minimal log discrepancy on a smooth surface.
Such a divisor is obtained by a weighted blow-up. There exists an example of a
pair such that any divisor computing the minimal log discrepancy computes no
log canonical thresholds.


title:
Integrated Transmission & Distribution System Modeling and Analysis:
  Need & Advantages

abstract:
  The primary objective of this paper is to highlight the need for and benefits
of studying the steady state and dynamic response of power systems using three
phase integrated transmission and distribution (T&D) system models (hereafter
referred to as hybrid models). Modeling and simulation requirements for
building and analyzing hybrid models are also discussed. Finally, results from
steady state and dynamic simulations of a large hybrid model are presented to
demonstrate insights that can be obtained from hybrid models which cannot be
obtained from the study of transmission and distribution systems separately.


title: Duality in entanglement of macroscopic states of light

abstract:
  We investigate duality in entanglement of a bipartite multi-photon system
generated from a coherent state of light. The system can exhibit polarization
entanglement if the two parts are distinguished by their parity, or parity
entanglement if the parts are distinguished by polarization. It was shown in
[PRL 110, 140404 (2013)] that this phenomenon can be exploited as a method to
test indistinguishability of two particles and it was conjectured that one can
also test indistinguishability of macroscopic systems. We propose a setup to
test this conjecture. Contrary to the previous studies using two-particle
interference effect as in Hong-Ou- Mandel setup, our setup neither assumes that
the tested state is composed of single particles nor requires that the total
number of particles be fixed. Consequently the notion of entanglement duality
is shown to be compatible with a broader class of physical systems. Moreover,
by observing duality in entanglement in the above system one can confirm that
macroscopic systems exhibit quantum behaviour. As a practical side,
entanglement duality is a useful concept that enables adaptive conversion of
entanglement of one degree of freedom (DOF) to that of another DOF according to
varying quantum protocols.


title:
Adversarial Deep Averaging Networks for Cross-Lingual Sentiment
  Classification

abstract:
  In recent years great success has been achieved in sentiment classification
for English, thanks in part to the availability of copious annotated resources.
Unfortunately, most languages do not enjoy such an abundance of labeled data.
To tackle the sentiment classification problem in low-resource languages
without adequate annotated data, we propose an Adversarial Deep Averaging
Network (ADAN) to transfer the knowledge learned from labeled data on a
resource-rich source language to low-resource languages where only unlabeled
data exists. ADAN has two discriminative branches: a sentiment classifier and
an adversarial language discriminator. Both branches take input from a shared
feature extractor to learn hidden representations that are simultaneously
indicative for the classification task and invariant across languages.
Experiments on Chinese and Arabic sentiment classification demonstrate that
ADAN significantly outperforms state-of-the-art systems.


title:
Extragradient and linesearch algorithms for solving equilibrium problems
  and fixed point problems in Banach spaces

abstract:
  In this paper, using sunny generalized nonexpansive retraction, we propose
new extragradient and linesearch algorithms for finding a common element of the
set of solutions of an equilibrium problem and the set of fixed points of a
relatively nonexpansive mapping in Banach spaces. To prove strong convergence
of iterates in the extragradient method, we introduce a $\phi$-Lipschitz-type
condition and assume that the equilibrium bifunction satisfies in this
condition. This condition is unnecessary when the linesearch method is used
instead of the extragradient method. A numerical example is given to illustrate
the usability of our results. Our results generalize, extend and enrich some
existing results in the literature.


title: Surface and corner free energies of the self-dual Potts model

abstract:
  We consider the bulk, vertical surface, horizontal surface and corner free
energies $f_b, f_s, f'_s, f_c$ of the anisotropic self-dual $Q$-state Potts
model for $Q > 4$. $f_b$ was calculated in 1973[1]. For $Q<4$, $f_s, f'_s$ were
calculated in 1989[2]. Here we extend this last calculation to $Q>4$ and find
agreement with the conjectures made in 2012 by Vernier and Jacobsen (VJ)[3] for
the isotropic case. All these four free energies satisfy inversion and rotation
relations. Together with some plausible analyticity assumptions, these provide
a less rigorous, but much simpler, way of determining $f_b, f_s, f'_s$. They
also imply that $f_c$ is independent of the anisotropy, being a function only
of $Q$, in which respect they resemble the order parameters of the associated
six-vertex model. Hence VJ's conjecture for $f_c$ should apply to the full
anisotropic model.


title: Berry-Esseen theorems under weak dependence

abstract:
  Let $\{{X}_k\}_{k\geq\mathbb{Z}}$ be a stationary sequence. Given $p\in(2,3]$
moments and a mild weak dependence condition, we show a Berry-Esseen theorem
with optimal rate $n^{p/2-1}$. For $p\geq4$, we also show a convergence rate of
$n^{1/2}$ in $\mathcal{L}^q$-norm, where $q\geq1$. Up to $\log n$ factors, we
also obtain nonuniform rates for any $p>2$. This leads to new optimal results
for many linear and nonlinear processes from the time series literature, but
also includes examples from dynamical system theory. The proofs are based on a
hybrid method of characteristic functions, coupling and conditioning arguments
and ideal metrics.


title:
On approximate continuity and the support of reflected stochastic
  differential equations

abstract:
  In this paper we prove an approximate continuity result for stochastic
differential equations with normal reflections in domains satisfying Saisho's
conditions, which together with the Wong-Zakai approximation result completes
the support theorem for such diffusions in the uniform convergence topology.
Also by adapting Millet and Sanz-Sol\'{e}'s idea, we characterize in H\"{o}lder
norm the support of diffusions reflected in domains satisfying the
Lions-Sznitman conditions by proving limit theorems of adapted interpolations.
Finally we apply the support theorem to establish a boundary-interior maximum
principle for subharmonic functions.


title: Large deviation principle for Poisson driven SDEs in epidemic models

abstract:
  We consider a general class of epidemic models obtained by applying a random
time change to a collection of Poisson processes and we show the large
deviation principle for such models. We generalize to a more general situation
the approach followed by Dolgoaschinnykh [3] in the case of the SIR epidemic
model. Thanks to an assumption which is satisfied in many examples, we simplify
the recent work by P. Kratz and E. Pardoux [8].


title:
Non-singular $\mathbb{Z}^d$-actions: an ergodic theorem over rectangles
  with application to the critical dimensions

abstract:
  We adapt techniques of Hochman to prove a non-singular ergodic theorem for
$\mathbb{Z}^d$-actions where the sums are over rectangles with side lengths
increasing at arbitrary rates, and in particular are not necessarily balls of a
norm. This result is applied to show that the critical dimensions with respect
to sequences of such rectangles are invariants of metric isomorphism. These
invariants are calculated for a class of product actions.


title: Photo Aesthetics Ranking Network with Attributes and Content Adaptation

abstract:
  Real-world applications could benefit from the ability to automatically
generate a fine-grained ranking of photo aesthetics. However, previous methods
for image aesthetics analysis have primarily focused on the coarse, binary
categorization of images into high- or low-aesthetic categories. In this work,
we propose to learn a deep convolutional neural network to rank photo
aesthetics in which the relative ranking of photo aesthetics are directly
modeled in the loss function. Our model incorporates joint learning of
meaningful photographic attributes and image content information which can help
regularize the complicated photo aesthetics rating problem.
  To train and analyze this model, we have assembled a new aesthetics and
attributes database (AADB) which contains aesthetic scores and meaningful
attributes assigned to each image by multiple human raters. Anonymized rater
identities are recorded across images allowing us to exploit intra-rater
consistency using a novel sampling strategy when computing the ranking loss of
training image pairs. We show the proposed sampling strategy is very effective
and robust in face of subjective judgement of image aesthetics by individuals
with different aesthetic tastes. Experiments demonstrate that our unified model
can generate aesthetic rankings that are more consistent with human ratings. To
further validate our model, we show that by simply thresholding the estimated
aesthetic scores, we are able to achieve state-or-the-art classification
performance on the existing AVA dataset benchmark.


title:
Nonlinear two-dimensional terahertz photon echo and rotational
  spectroscopy in the gas phase

abstract:
  Ultrafast two-dimensional spectroscopy utilizes correlated multiple
light-matter interactions for retrieving dynamic features that may otherwise be
hidden under the linear spectrum. Its extension to the terahertz regime of the
electromagnetic spectrum, where a rich variety of material degrees of freedom
reside, remains an experimental challenge. Here we report ultrafast
two-dimensional terahertz spectroscopy of gas-phase molecular rotors at room
temperature. Using time-delayed terahertz pulse pairs, we observe photon echoes
and other nonlinear signals resulting from molecular dipole orientation induced
by three terahertz field-dipole interactions. The nonlinear time-domain
orientation signals are mapped into the frequency domain in two-dimensional
rotational spectra which reveal J-state-resolved nonlinear rotational dynamics.
The approach enables direct observation of correlated rotational transitions
and may reveal rotational coupling and relaxation pathways in the ground
electronic and vibrational state.


title: Position-Indexed Formulations for Kidney Exchange

abstract:
  A kidney exchange is an organized barter market where patients in need of a
kidney swap willing but incompatible donors. Determining an optimal set of
exchanges is theoretically and empirically hard. Traditionally, exchanges took
place in cycles, with each participating patient-donor pair both giving and
receiving a kidney. The recent introduction of chains, where a donor without a
paired patient triggers a sequence of donations without requiring a kidney in
return, increased the efficacy of fielded kidney exchanges---while also
dramatically raising the empirical computational hardness of clearing the
market in practice. While chains can be quite long, unbounded-length chains are
not desirable: planned donations can fail before transplant for a variety of
reasons, and the failure of a single donation causes the rest of that chain to
fail, so parallel shorter chains are better in practice.
  In this paper, we address the tractable clearing of kidney exchanges with
short cycles and chains that are long but bounded. This corresponds to the
practice at most modern fielded kidney exchanges. We introduce three new
integer programming formulations, two of which are compact. Furthermore, one of
these models has a linear programming relaxation that is exactly as tight as
the previous tightest formulation (which was not compact) for instances in
which each donor has a paired patient. On real data from the UNOS nationwide
exchange in the United States and the NLDKSS nationwide exchange in the United
Kingdom, as well as on generated realistic large-scale data, we show that our
new models are competitive with all existing solvers---in many cases
outperforming all other solvers by orders of magnitude.


title: Feature-rich electronic properties of aluminum-doped graphenes

abstract:
  The electronic properties of aluminum-doped graphenes enriched by
multi-orbital hybridizations are investigated using first-principles
calculations. The feature-rich electronic structures exhibit the quasi-rigid
red shifts of the carbon-created energy bands, the Al-dominated valence and
conduction bands, and many free electrons in the conduction Dirac cone. These
are directly reflected in the special structures of density of states (DOS).
The Al- and alkali-induced high free carrier densities are almost the same.
There exist certain important differences among the Al-, alkali- and
halogen-doped grapehenes, such as, the buckled or planar graphene, the
preserved or seriously distorted Dirac cone, the existence of the
adatom-dominated valence bands, the free electrons or holes, the degenerate or
splitting spin-related states, and the simple or complicated peaks in DOS. The
similarities and differences mainly come from the diverse orbital
hybridizations in adatom-C bonds, as indicated from the atom-dominated bands,
the spatial charge distributions and the orbital-projected DOS.


title: Deformation of minimal surfaces with planar curvature lines

abstract:
  Minimal surfaces with planar curvature lines are classical geometric objects,
having been studied since the late 19th century. In this paper, we revisit the
subject from a different point of view. After calculating their metric
functions using an analytical method, we recover the Weierstrass data, and give
clean parametrizations for these surfaces. Then, using these parametrizations,
we show that there exists a single continuous deformation between all minimal
surfaces with planar curvature lines. In the process, we establish the
existence of axial directions for these surfaces.


title:
Frequency locking in auditory hair cells: Distinguishing between
  additive and parametric forcing

abstract:
  The auditory system displays remarkable sensitivity and frequency
discrimination, attributes shown to rely on an amplification process that
involves a mechanical as well as a biochemical response. Models that display
proximity to an oscillatory onset (a.k.a. Hopf bifurcation) exhibit a resonant
response to distinct frequencies of incoming sound, and can explain many
features of the amplification phenomenology. To understand the dynamics of this
resonance, frequency locking is examined in a system near the Hopf bifurcation
and subject to two types of driving forces: additive and parametric. Derivation
of a universal amplitude equation that contains both forcing terms enables a
study of their relative impact on the hair cell response. In the parametric
case, although the resonant solutions are 1:1 frequency locked, they show the
coexistence of solutions obeying a phase shift of $\pi$, a feature typical of
the 2:1 resonance. Different characteristics are predicted for the transition
from unlocked to locked solutions, leading to smooth or abrupt dynamics in
response to different types of forcing. The theoretical framework provides a
more realistic model of the auditory system, which incorporates a direct
modulation of the internal control parameter by an applied drive. The results
presented here can be generalized to many other media, including Faraday waves,
chemical reactions, and nonlinear optics, which are known to exhibit resonant
behavior.


title: Schwarz type model comparison for LAQ models

abstract:
  For model-specification purpose, we study asymptotic behavior of the marginal
quasi-log likelihood associated with a family of locally asymptotically
quadratic (LAQ) statistical experiments. Our result entails a far-reaching
extension of applicable scope of the classical approximate Bayesian model
comparison due to Schwarz, with frequentist-view theoretical foundation. In
particular, the proposed statistics can deal with both ergodic and non-ergodic
stochastic-process models, where the corresponding $M$-estimator is of
multi-scaling type and the asymptotic quasi-information matrix is random.
Focusing on the ergodic diffusion model, we also deduce the consistency of the
multistage optimal-model selection where we may select an optimal sub-model
structure step by step, so that computational cost can be much reduced. We
illustrate the proposed method by the Gaussian quasi-likelihood for
diffusion-type models in details, together with several numerical experiments.


title: SIMP from a strong U(1) gauge theory with a monopole condensation

abstract:
  We provide a variant model of strongly interacting massive particle (SIMP),
where composite dark matter comes from a strongly interacting U(1) theory. We
first explain a non-Abelian version of the model with an additional singlet
field, which is mixed with the Higgs field to maintain the kinetic equilibrium
between the hidden and Standard Model (SM) sectors. The mixing leads to signals
that would be detected by future collider experiments, direct DM detection
experiments, and beam-dump experiments. Then we investigate a U(1) theory with
a scalar monopole, where U(1) charged particles are confined by monopole
condensation. In this model, the radial component of monopole can mix with the
Higgs field, so that we do not need to introduce the additional singlet field.


title:
Convergence in distribution norms in the CLT for non identical
  distributed random variables

abstract:
  We study the convergence in distribution norms in the Central Limit Theorem
for non identical distributed random variables that is $$
\varepsilon_{n}(f):={\mathbb{E}}\Big(f\Big(\frac 1{\sqrt
n}\sum_{i=1}^{n}Z_{i}\Big)\Big)-{\mathbb{E}}\big(f(G)\big)\rightarrow 0 $$
where $Z_{i}$ are centred independent random variables and $G$ is a Gaussian
random variable. We also consider local developments (Edgeworth expansion).
This kind of results is well understood in the case of smooth test functions
$f$. If one deals with measurable and bounded test functions (convergence in
total variation distance), a well known theorem due to Prohorov shows that some
regularity condition for the law of the random variables $Z_{i}$, $i\in
{\mathbb{N}}$, on hand is needed. Essentially, one needs that the law of $
Z_{i}$ is locally lower bounded by the Lebesgue measure (Doeblin's condition).
This topic is also widely discussed in the literature. Our main contribution is
to discuss convergence in distribution norms, that is to replace the test
function $f$ by some derivative $\partial_{\alpha }f$ and to obtain upper
bounds for $\varepsilon_{n}(\partial_{\alpha }f)$ in terms of the infinite norm
of $f$. Some applications are also discussed: an invariance principle for the
occupation time for random walks, small balls estimates and expected value of
the number of roots of trigonometric polynomials with random coefficients.


title: A Splitting Method for Deep Water with Bathymetry

abstract:
  In this paper we derive and prove the wellposedness of a deep water model
that generalizes the Saut-Xu system for nonflat bottoms. Then, we present a new
numerical method based on a splitting approach for studying this system. The
advantage of this method is that it does not require any low pass filter to
avoid spurious oscillations. We prove a local error estimate and we show that
our scheme represents a good approximation of order one in time. Then, we
perform some numerical experiments which confirm our theoretical result and we
study three physical phenomena : the evolution of water waves over a rough
bottom; the evolution of a KdV soliton when the shallowness parameter
increases; the homogenization effect of rapidly varying topographies on water
waves.


title: Concepts of Classification and Taxonomy. Phylogenetic Classification

abstract:
  Phylogenetic approaches to classification have been heavily developed in
biology by bioinformaticians. But these techniques have applications in other
fields, in particular in linguistics. Their main characteristics is to search
for relationships between the objects or species in study, instead of grouping
them by similarity. They are thus rather well suited for any kind of
evolutionary objects. For nearly fifteen years, astrocladistics has explored
the use of Maximum Parsimony (or cladistics) for astronomical objects like
galaxies or globular clusters. In this lesson we will learn how it works. 1 Why
phylogenetic tools in astrophysics? 1.1 History of classification The need for
classifying living organisms is very ancient, and the first classification
system can be dated back to the Greeks. The goal was very practical since it
was intended to distinguish between eatable and toxic aliments, or kind and
dangerous animals. Simple resemblance was used and has been used for centuries.
Basically, until the XVIIIth century, every naturalist chose his own criterion
to build a classification. At the end, hundreds of classifications were
available, most often incompatible to each other. The criteria for this
traditional way of classifying is the subjective appearance of the living
organisms. During the XVIIIth a revolution occurred. Scientists like Adanson
and Linn{\'e} devised new ways of classifying the objects and naming the
classes. Adanson realised that all the observable traits should be used, giving
birth to the mutivariate clustering and classification activity (Adanson,
1763). Linn{\'e} based his binomial nomenclature on neutral names unrelated
whatsoever to any property of the classes. We can realise the success of these
two ideas more than two centuries and a half later!


title:
Orbital Magnetism of Bloch Electrons II. Application to Single-Band
  Models and Corrections to Landau-Peierls susceptibility

abstract:
  Orbital susceptibility for Bloch electrons is calculated for the first time
up to the first order with respect to overlap integrals between the neighboring
atomic orbitals, assuming single-band models. A general and rigorous theory of
orbital susceptibility developed in the preceding paper is applied to
single-band models in two-dimensional square and triangular lattices. In
addition to the Landau-Peierls orbital susceptibility, it is found that there
are comparable contributions from the Fermi surface and from the occupied
states in the partially filled band called intraband atomic diamagnetism. This
result means that the Peierls phase used in tight-binding models is
insufficient as the effect of magnetic field.


title: Conditions for a L\'evy process to stay positive near 0, in probability

abstract:
  A necessary and sufficient condition for a L\'evy process $X$ to stay
positive, in probability, near 0, which arises in studies of Chung-type laws
for $X$ near 0, is given in terms of the characteristics of $X$.


title: Number of clusters, deconvolution and classical problem of moments

abstract:
  In the paper there is given a connection between one special case of cluster
analysis, deconvolution problem, and classical moment problem. Namely, the
methods used there are applied to solve deconvolution problem for the case of
one known distribution and another one concentrated in unknown finite number of
points. These results can be applied to estimate a number of clusters for the
case of scale or location mixture of identical distributions.
  keywords: number of clusters, deconvolution problem, classical moment
problem, scale and location mixtures.


title:
Effect of magnetic field on intersubband polaritons in a quantum well:
  Strong to weak coupling conversion

abstract:
  We investigate theoretically the effect of a magnetic field on intersubband
polaritons in an asymmetric quantum well placed inside an optical resonator. It
is demonstrated that the field-induced diamagnetic shift of electron subbands
in the well increases the broadening of optical lines corresponding to
intersubband electron transitions. As a consequence, the magnetic field can
switch the polariton system from the regime of strong light-matter coupling to
the regime of weak one. This effect paves a way to the effective control of
polaritonic devices with a magnetic field.


title:
One-step approach to ARPES from strongly correlated solids: a
  Mott-Hubbard system

abstract:
  An expression is derived for angle-resolved photocurrent from a semi-infinite
correlated system. Within the sudden approximation, the photocurrent is
proportional to the spectral function of a one-particle two-time retarded
Green's function $\mathcal{G}$ of an operator that creates an electron in a
special quantum state $\chi$ localized at the surface. For a system described
by a many-body single-band model we present an analytical expression that
relates the Green's function $\mathcal{G}$ with the Green's function of an
infinite crystal $G_{b,\mathbf{k}}(\omega)$ in Wannier representation. The role
of final states and of the crystal surface is analysed for a model Green's
function of the infinite crystal with a three-peak spectral function typical of
a Mott-Hubbard metal. The momentum dependence of both the quasiparticle pole
position and the spectral weight of the incoherent band manifest themselves in
the shape of the photocurrent energy distribution curve.


title:
On the distribution of Rudin-Shapiro polynomials and lacunary walks on
  $SU(2)$

abstract:
  We characterize the limiting distribution of Rudin-Shapiro polynomials,
showing that, normalized, their values become uniformly distributed in the
disc. This resolves conjectures of Saffari and Montgomery. Our proof proceeds
by relating the polynomials' distribution to that of a product of weakly
dependent random matrices, which we analyze using the representation theory of
$SU(2)$. Our approach leads us to a non-commutative analogue of the classical
central limit theorem of Salem and Zygmund, which may be of independent
interest.


title: Distance-based Control of K4 Formation with Almost Global Convergence

abstract:
  In this paper, we propose a distance-based formation control strategy that
can enable four mobile agents, which are modelled by a group of
single-integrators, to achieve the desired formation shape specified by using
six consistent inter-agent distances in a 2-dimensional space. The control law
is closely related to a gradient-based control law formed from a potential
function reflecting the error between the actual inter-agent distances and the
desired inter-agent distances. There are already control strategies achieving
the same objective in a distance-based control manner in the literature, but
the results do not yet include a global as opposed to local stability analysis.
We propose a control strategy modified from the existing gradient-based control
law so that we can achieve almost global convergence to the desired formation
shape, and the control law uses known properties for an associated formation
shape control problem involving a four-agent tetrahedron formation in
3-dimensional space. Simulation results verifying our analysis are also
presented.


title: The trunkenness of a volume-preserving vector field

abstract:
  We construct a new invariant-the trunkenness-for volume-perserving vector
fields on S^3 up to volume-preserving diffeomorphism. We prove that the
trunkenness is independent from the helicity and that it is the limit of a knot
invariant (called the trunk) computed on long pieces of orbits.

categories: math.DS astro-ph.SR math.GT physics.flu-dyn physics.plasm-ph


title: Another piece of the puzzle: the fast HI outflow in Mrk231

abstract:
  We present the detection, performed with the Westerbork Synthesis Radio
Telescope (WSRT) and the Karl Jansky Very Large Array (VLA), of a fast HI 21-cm
outflow in the ultra-luminous infrared galaxy Mrk 231. The outflow is observed
as shallow HI absorption blueshifted ~1300 km/s with respect to the systemic
velocity and located against the inner kpc of the radio source. The outflowing
gas has an estimated column density between 5 and 15x10^18 Tspin cm^-2. We
derive the Tspin to lie in the range 400-2000 K and the densities are
n_HI~10-100 cm^-3. Our results confirm the multiphase nature of the outflow in
Mrk231. Although effects of the interaction between the radio plasma and the
surrounding medium cannot be ruled out, the energetics and the lack of a clear
kpc-scale jet suggest that the most likely origin of the HI outflow is a
wide-angle nuclear wind, as earlier proposed to explain the neutral outflow
traced by NaI and molecular gas. Our results suggest that an HI component is
present in fast outflows regardless of the acceleration mechanism (wind vs jet
driven) and that it must be connected with common properties of the
pre-interaction gas. Considering the observed similarity of their column
densities, the HI outflow likely represents the inner part of the broad wind
identified on larger scales in NaI. The mass outflow rate of the HI outflow
does not appear to be as large as the one observed in molecular gas. These
characteristics suggest that the HI may represent a short intermediate phase in
the rapid cooling of the gas. We also obtained deeper continuum images than
previously available. At the resolution of ~1arcsec we do not see a kpc-scale
jet. Instead, we detect a plateau of emission, likely due to star formation,
surrounding the bright nuclear region. We also detect a poorly collimated
bridge which may represent the channel feeding the southern lobe.


title: Simulation of Radiation Energy Release in Air Showers

abstract:
  A simulation study of the energy released by extensive air showers in the
form of MHz radiation is performed using the CoREAS simulation code. We develop
an efficient method to extract this radiation energy from air-shower
simulations. We determine the longitudinal profile of the radiation energy
release and compare it to the longitudinal profile of the energy deposit by the
electromagnetic component of the air shower. We find that the radiation energy
corrected for the geometric dependence of the geomagnetic emission scales
quadratically with the energy in the electromagnetic component of the air
shower with a second-order dependence on the atmospheric density at the
position of the maximum shower development $X_\mathrm{max}$. In a measurement
where $X_\mathrm{max}$ is not accessible, this second order dependence can be
approximated using the zenith angle of the incoming direction of the air shower
with only a minor loss in accuracy. Our method results in an intrinsic
uncertainty of 4% in the determination of the energy in the electromagnetic
air-shower component, which is well below current experimental uncertainties.


title:
An introduction to Differential Linear Logic: proof-nets, models and
  antiderivatives

abstract:
  Differential Linear Logic enriches Linear Logic with additional logical rules
for the exponential connectives, dual to the usual rules of dereliction,
weakening and contraction. We present a proof-net syntax for Differential
Linear Logic and a categorical axiomatization of its denotational models. We
also introduce a simple categorical condition on these models under which a
general antiderivative operation becomes available. Last we briefly describe
the model of sets and relations and give a more detailed account of the model
of finiteness spaces and linear and continuous functions.


title:
Etale representations for reductive algebraic groups with
  one-dimensional center

abstract:
  A complex vector space $V$ is a prehomogeneous $G$-module if $G$ acts
rationally on $V$ with a Zariski-open orbit. The module is called etale if
$\dim V=\dim G$. We study etale modules for reductive algebraic groups $G$ with
one-dimensional center. For such $G$, even though every etale module is a
regular prehomogeneous module, its irreducible submodules have to be
non-regular. For these non-regular prehomogeneous modules, we determine some
strong constraints on the ranks of their simple factors. This allows us to show
that there do not exist etale modules for $G=\mathrm{GL}_1\times
S\times\cdots\times S$, with $S$ simple.


title:
Exponential decay of correlations for a real-valued dynamical system
  generated by a k dimensional system

abstract:
  We study the real, bounded-variables process (X_n) defined by a k-term
recurrence relation X_{n+k} ={\phi}(X_n, ... , X_{n+k-1}). We prove the decay
of correlations, mainly under purely analytic hypotheses concerning the
function {\phi} and its partial derivatives.


title: Nonequilibrium Majorana fluctuations

abstract:
  Nonequilibrium physics of random events, or fluctuations, is a unique
fingerprint of a given system. Here we demonstrate that in noninteracting
systems, whose dynamics is driven by Majorana states, the effective charge
$e^*$, characterizing the electric current fluctuations, is fractional. This is
in contrast to noninteracting Dirac systems with the trivial electronic charge,
$e^*=e$. Quite the opposite, in the Majorana state we predict two different
fractional effective charges at low and high energies, $e^*_l=e/2$ and
$e^*_h=3e/2$, accessible at low and high bias voltages, respectively. We show
that while the low energy effective charge $e^*_l$ is sensitive to thermal
fluctuations of the current, the high energy effective charge $e^*_h$ is robust
against thermal noise. A unique fluctuation signature of Majorana fermions is,
therefore, encoded in the high voltage tails of the electric current noise
easily accessible in experiments on strongly nonequilibrium systems even at
high temperatures.


title:
Controlled Capillary Assembly of Magnetic Janus Particles at Fluid-Fluid
  Interfaces

abstract:
  Capillary interactions can be used to direct assembly of particles adsorbed
at fluid-fluid interfaces. Precisely controlling the magnitude and direction of
capillary interactions to assemble particles into favoured structures for
materials science purposes is desirable but challenging. In this paper, we
investigate capillary interactions between magnetic Janus particles adsorbed at
fluid-fluid interfaces. We develop a pair-interaction model that predicts that
these particles should arrange into a side--side configuration, and carry out
simulations that confirm the predictions of our model. Finally, we investigate
the monolayer structures that form when many magnetic Janus particles adsorb at
the interface. We find that the particles arrange into long, straight chains
exhibiting little curvature, in contrast with capillary interactions between
ellipsoidal particles. We further find a regime in which highly ordered,
lattice-like monolayer structures form, which can be tuned dynamically using an
external magnetic field.


title: On the intersection graphs of modules and rings

abstract:
  We classify modules and rings with some specific properties of their
intersection graphs. In particular, we describe rings with infinite
intersection graphs containing maximal left ideals of finite degree. This
answers a question raised in [A2]. We also generalize this result to modules,
i.e. we get the structure theorem of modules for which their intersection
graphs are infinite and contain maximal submodules of finite degree.
Furthermore we omit the assumption of maximality of submodules and still get a
satisfactory characterization of such modules. In addition we show that, if the
intersection graph of a module is infinite but its clique number is finite,
then the clique and chromatic numbers of the graph coincide. This fact was
known earlier only in some particular cases. It appears that such equality
holds also in the complement graph.


title:
Relaxed Large Economies with Infinite-Dimensional Commodity Spaces: The
  Existence of Walrasian Equilibria

abstract:
  Whereas "convexification by aggregation" is a well-understood procedure in
mathematical economics, "convexification by randomization" has largely been
limited to theories of statistical decision-making, optimal control and
non-cooperative games. In this paper, in the context of classical Walrasian
general equilibrium theory, we offer a comprehensive treatment of {\it relaxed
economies} and their {\it relaxed Walrasian equilibria}: our results pertain to
a setting with a finite or a continuum of agents, and a continuum of
commodities modeled either as an ordered separable Banach space or as an
$L^\infty$-space. As a substantive consequence, we demonstrate that the
convexity hypothesis can be removed from the original large economy under the
saturation hypothesis, and that existing results in the antecedent literature
can be effortlessly recovered.


title:
Double-spin asymmetry $A^{\cos\phi_S}_{LT}$ in semi-inclusive DIS at
  CLAS12 and EIC within the collinear framework

abstract:
  We study the longitudinal-transverse double-spin asymmetry with a
$\cos\phi_S$ modulation in semi-inclusive deep inelastic scattering for charged
and neutral pions production. We consider the particular case in which the
transverse momentum of the final state hadron is integrated out. The
corresponding asymmetry may be contributed by two parts: one is the convolution
of the twist-3 distribution function $g_{T}(x)$ and the unpolarized
fragmentation function $D_1(z)$, the other is related to the coupling of the
transversity distribution function $h_1(x)$ and the collinear twist-3
fragmentation function $\tilde{E}(z)$. We take into account both contributions
to predict the $\cos\phi_S$ asymmetry at the kinematics of CLAS12 and a future
Electron Ion Collider. We find that the asymmetry of pion production at CLAS12
is sizable, and $\tilde{E}(z)$ can play an important role in the asymmetry in
the large-$z$ region.


title:
Axial charges of hyperons and charmed baryons using $N_f=2+1+1$ twisted
  mass fermions

abstract:
  The axial couplings of the low lying baryons are evaluated using a total of
five ensembles of dynamical twisted mass fermion gauge configurations. The
simulations are performed using the Iwasaki gauge action and two degenerate
flavors of light quarks, and a strange and a charm quark fixed to approximately
their physical values at two values of the coupling constant. The lattice
spacings, determined using the nucleon mass, are $a=0.082$ fm and $a=0.065$ fm
and the simulations cover a pion mass in the range of about 210 MeV to 430 MeV.
We study the dependence of the axial couplings on the pion mass in the range of
about 210 MeV to 430 MeV as well as the $SU(3)$ breaking effects as we decrease
the light quark mass towards its physical value.


title:
Feedforward Initialization for Fast Inference of Deep Generative
  Networks is biologically plausible

abstract:
  We consider deep multi-layered generative models such as Boltzmann machines
or Hopfield nets in which computation (which implements inference) is both
recurrent and stochastic, but where the recurrence is not to model sequential
structure, only to perform computation. We find conditions under which a simple
feedforward computation is a very good initialization for inference, after the
input units are clamped to observed values. It means that after the feedforward
initialization, the recurrent network is very close to a fixed point of the
network dynamics, where the energy gradient is 0. The main condition is that
consecutive layers form a good auto-encoder, or more generally that different
groups of inputs into the unit (in particular, bottom-up inputs on one hand,
top-down inputs on the other hand) are consistent with each other, producing
the same contribution into the total weighted sum of inputs. In biological
terms, this would correspond to having each dendritic branch correctly
predicting the aggregate input from all the dendritic branches, i.e., the soma
potential. This is consistent with the prediction that the synaptic weights
into dendritic branches such as those of the apical and basal dendrites of
pyramidal cells are trained to minimize the prediction error made by the
dendritic branch when the target is the somatic activity. Whereas previous work
has shown how to achieve fast negative phase inference (when the model is
unclamped) in a predictive recurrent model, this contribution helps to achieve
fast positive phase inference (when the target output is clamped) in such
recurrent neural models.


title:
Distribution of energetic oxygen and hydrogen in the near-Earth plasma
  sheet

abstract:
  The spatial distributions of different ion species are useful indicators for
plasma sheet dynamics. In this statistical study based on 7 years of Cluster
observations, we establish the spatial distributions of oxygen ions and protons
at energies from 274 to 955 keV, depending on geomagnetic and solar wind (SW)
conditions. Compared with protons, the distribution of energetic oxygen has
stronger dawn-dusk asymmetry in response to changes in the geomagnetic
activity. When the interplanetary magnetic field (IMF) is directed southward,
the oxygen ions show significant acceleration in the tail plasma sheet. Changes
in the SW dynamic pressure ($\mathit{P}_{dyn}$) affect the oxygen and proton
intensities in the same way. The energetic protons show significant intensity
increases at the near-Earth duskside during disturbed geomagnetic conditions,
enhanced SW $\mathit{P}_{dyn}$, and southward IMF, implying there location of
effective inductive acceleration mechanisms and a strong duskward drift due to
the increase of the magnetic field gradient in the near-Earth tail. Higher
losses of energetic ions are observed in the dayside plasma sheet under
disturbed geomagnetic conditions and enhanced SW $\mathit{P}_{dyn}$. These
observations are in agreement with theoretical models.


title: Superconformal index with surface defects for class ${\cal S}_k$

abstract:
  We study surface defects in 4d $\mathcal{N}=1$ $SU(N)$ superconformal gauge
theories of class $\mathcal{S}_k$ obtained from the 6d (1,0) theories of type
$A_{N-1}$, which are worldvolume theories on $N$ M5-branes at
$\mathbb{C}^2/\mathbb{Z}_k$ singularities, compactified on Riemann surfaces
with punctures. First we apply a method based on Riemann surface description
and obtain the superconformal index of the theories in the presence of surface
defects labelled by arbitrary symmetric representations of $su(N)$. Then we
propose another description for the same surface defects, which involves 4d-2d
coupled systems, by identifying which 2d $\mathcal{N}=(0,2)$ theories should be
coupled. We compute the index of the 4d-2d systems and reproduce the results
obtained from the first method. Finally we study the 2d TQFT structure of the
index for class $\mathcal{S}_{k}$ theories by obtaining several eigenfunctions
and eigenvalues of the difference operators that capture the surface defects
and checking their relation.


title: Cohomology and deformations of Courant pairs

abstract:
  In this note we define a notion of Courant pair as a Courant algebra over the
Lie algebra of linear derivations on an associative algebra. We study formal
deformations of Courant pairs by constructing a cohomology bicomplex with
coefficients in a module from the cochain complexes defining Hochschild
cohomology and Leibniz cohomology.


title: The Circle Game: Scalable Private Membership Test Using Trusted Hardware

abstract:
  Malware checking is changing from being a local service to a cloud-assisted
one where users' devices query a cloud server, which hosts a dictionary of
malware signatures, to check if particular applications are potentially
malware. Whilst such an architecture gains all the benefits of cloud-based
services, it opens up a major privacy concern since the cloud service can infer
personal traits of the users based on the lists of applications queried by
their devices. Private membership test (PMT) schemes can remove this privacy
concern. However, known PMT schemes do not scale well to a large number of
simultaneous users and high query arrival rates. We propose a simple PMT
approach using a carousel: circling the entire dictionary through trusted
hardware on the cloud server. Users communicate with the trusted hardware via
secure channels. We show how the carousel approach, using different data
structures to represent the dictionary, can be realized on two different
commercial hardware security architectures (ARM TrustZone and Intel SGX). We
highlight subtle aspects of securely implementing seemingly simple PMT schemes
on these architectures. Through extensive experimental analysis, we show that
for the malware checking scenario our carousel approach surprisingly
outperforms Path ORAM on the same hardware by supporting a much higher query
arrival rate while guaranteeing acceptable response latency for individual
queries.


title:
Effect of the edge states on the conductance and thermopower in Zigzag
  Phosphorene Nanoribbons

abstract:
  We numerically study the effect of the edge states on the conductance and
thermopower in zigzag phosphorene nanoribbons (ZPNRs) based on the
tight-binding model and the scattering-matrix method. It is interesting to find
that the band dispersion, conductance, and thermopower can be modulated by
applying a bias voltage and boundary potentials to the two layers of the ZPNRs.
Under the certain bias voltage, the two-fold degenerate quasi-flat edge bands
split perfectly. The conductance can be switched off, and the thermopower
around zero energy increases. In addition, when only the boundary potential of
the top layer or bottom layer is adjusted, only one edge band bends and merges
into the bulk band. The first conductance plateau is strongly decreased to
$e^2/h$ around zero energy. Particularly, when the two boundary potentials are
adjusted, all the edge bands bend and fully merge into the bulk band, and the
bulk energy gap is maximized. More interestingly, a pronounced conductance
plateau with $G=0$ is found around zero energy, which is attributable to the
opening of the bulk energy gap between the valence and conduction bands.
Meanwhile, the thermopower can be enhanced more than twice, compared to that of
the perfect ZPNRs. The large magnitude of thermopower is ascribed to the
appearance of the bulk energy gap around zero energy. Our results show that the
modulated ZPNRs are more reliable in thermoelectric application.


title:
Surface effect that causes a peak in band-edge photocurrent spectra: a
  quantitative model

abstract:
  Band edge photocurrent spectra are typically observed in either of two
shapes: a peak or a step. In this study, we show that the photocurrent band
edge response of a GaN layer forms a peak, while the same response in GaN
nanowires takes the form of a step, both are red-shifted to the actual band
edge energy. Although this apparent inconsistency is not limited to GaN, the
physics of this phenomenon has been unclear. To understand the physics behind
these observations, we propose a model explaining the apparent discrepancy as
resulting from a structure-dependent surface-effect. To test the model, we
experiment with a GaAs layer showing that we can deliberately switch between a
step and a peak. We demonstrate that using this quantitative model one may
obtain the exact band edge transition energy, regardless of the red-shift
variance, as well as the density of the surface state charges that cause the
red shift. The model thus adds quantitative features to photocurrent
spectroscopy.


title:
Heteroclinic structure of parametric resonance in the nonlinear
  Schr\"odinger equation

abstract:
  We show that the nonlinear stage of modulational instability induced by
parametric driving in the {\em defocusing} nonlinear Schr\"odinger equation can
be accurately described by combining mode truncation and averaging methods,
valid in the strong driving regime. The resulting integrable oscillator reveals
a complex hidden heteroclinic structure of the instability. A remarkable
consequence, validated by the numerical integration of the original model, is
the existence of breather solutions separating different Fermi-Pasta-Ulam
recurrent regimes. Our theory also shows that optimal parametric amplification
unexpectedly occurs outside the bandwidth of the resonance (or Arnold tongues)
arising from the linearised Floquet analysis.


title:
Duality and reciprocity of fluctuation-dissipation relations in
  conductors

abstract:
  By analogy with linear-response we formulate the duality and reciprocity
properties of current and voltage fluctuations expressed by Nyquist relations
including the intrinsic bandwidths of the respective fluctuations. For this
purpose we individuate total-number and drift-velocity fluctuations of carriers
inside a conductor as the microscopic sources of noise. The spectral densities
at low frequency of the current and voltage fluctuations and the respective
conductance and resistance are related in a mutual exclusive way to the
corresponding noise-source. The macroscopic variance of current and voltage
fluctuations are found to display a dual property via a plasma conductance that
admits a reciprocal plasma resistance. Analogously, the microscopic
noise-sources are found to obey a dual property and a reciprocity relation. The
formulation is carried out in the frame of the grand canonical (for current
noise) and canonical (for voltage noise) ensembles and results are derived
which are valid for classical as well as for degenerate statistics including
fractional exclusion statistics. The unifying theory so developed sheds new
light on the microscopic interpretation of dissipation and fluctuation
phenomena in conductors. In particular it is proven that, as a consequence of
the Pauli principle, for Fermions non-vanishing single-carrier velocity
fluctuations at zero temperature are responsible for diffusion but not for
current noise, which vanishes in this limit.


title:
Cutsize Distributions of Balanced Hypergraph Bipartitions for Random
  Hypergraphs

abstract:
  In a previous work, we presented a parallel encoding algorithm for
low-density parity-check (LDPC) codes by partitioning hypergraph representation
for the LDPC codes. The aim of this research is to analyze the processing time
of this encoding algorithm. This paper clarifies that the processing time of
the encoding algorithm depends on the minimum cutsize of balanced hypergraph
partitions. Moreover, this paper gives the typical minimum cutsize and cutsize
distribution for balanced hypergraph bipartitions of random hypergraphs defined
from a regular LDPC ensemble.


title:
From one-dimensional fields to Vlasov equilibria: Theory and application
  of Hermite polynomials

abstract:
  We consider the theory and application of a solution method for the inverse
problem in collisionless equilibria, namely that of calculating a
Vlasov-Maxwell equilibrium for a given macroscopic (fluid) equilibrium. Using
Jeans' Theorem, the equilibrium distribution functions are expressed as
functions of the constants of motion, in the form of a Maxwellian multiplied by
an unknown function of the canonical momenta. In this case it is possible to
reduce the inverse problem to inverting Weierstrass transforms, which we
achieve by using expansions over Hermite polynomials. A sufficient condition on
the pressure tensor is found which guarantees the convergence and the
boundedness of the candidate solution, when satisfied. This condition is
obtained by elementary means, and it is clear how to put it into practice. We
also argue that for a given pressure tensor for which our method applies, there
always exists a positive distribution function solution for a sufficiently
magnetised plasma. Illustrative examples of the use of this method with both
force-free and non-force-free macroscopic equilibria are presented, including
the full verification of a recently derived distribution function for the
force-free Harris Sheet (Allanson $\textit{et al., Phys. Plasmas}$, vol. 22
(10), 2015, 102116). In the effort to model equilibria with lower values of the
plasma beta, solutions for the same macroscopic equilibrium in a new gauge are
calculated, with numerical results presented for $\beta_{pl}=0.05$.


title:
Sparse polynomial chaos expansions of frequency response functions using
  stochastic frequency transformation

abstract:
  Frequency response functions (FRFs) are important for assessing the behavior
of stochastic linear dynamic systems. For large systems, their evaluations are
time-consuming even for a single simulation. In such cases, uncertainty
quantification by crude Monte-Carlo simulation is not feasible. In this paper,
we propose the use of sparse adaptive polynomial chaos expansions (PCE) as a
surrogate of the full model. To overcome known limitations of PCE when applied
to FRF simulation, we propose a frequency transformation strategy that
maximizes the similarity between FRFs prior to the calculation of the PCE
surrogate. This strategy results in lower-order PCEs for each frequency.
Principal component analysis is then employed to reduce the number of random
outputs. The proposed approach is applied to two case studies: a simple 2-DOF
system and a 6-DOF system with 16 random inputs. The accuracy assessment of the
results indicates that the proposed approach can predict single FRFs
accurately. Besides, it is shown that the first two moments of the FRFs
obtained by the PCE converge to the reference results faster than with the
Monte-Carlo (MC) methods.


title:
Transient response from Unruh-DeWitt detector along Rindler trajectory
  in polymer quantization

abstract:
  If an Unruh-DeWitt detector operates for an infinite proper time along the
trajectory of a uniformly accelerated observer in Fock space then induced
transition rate of the detector is proportional to Planck distribution. For a
realistic detector which operates only for a finite period, the instantaneous
transition rate contains both transient and non-transient terms. In particular,
the non-transient term contains a residue evaluated at the pole of the
two-point function. We show here by considering a massless scalar field that
unlike in Fock quantization, the short-distance two-point function contains no
pole in polymer quantization, the quantization techniques used in loop quantum
gravity. Consequently, corresponding transition rate of the Unruh-DeWitt
detector contains only transient terms. Thus, the result presented here
provides an alternative evidence for absence of Unruh effect in polymer
quantization which was shown earlier by the authors using methods of Bogoliubov
transformation and Kubo-Martin-Schwinger condition.


title: Rydberg-dressed atoms in BCS-state

abstract:
  We consider a system consisting of Rydberg dressed atoms interacting with BEC
condensate of diatomic molecules. Using random phase approximation (RPA) we
calculate the effective interactions between Rydberg atoms accounting for their
Wan der Waals repulsion and exchange of virtual excitations of the condensate
and demonstrate that total interaction can become attractive and BCS state of
Rydberg dressed atoms can be formed. Using the example of 6Li atoms we
demonstrate that the strength of the interactions can be controlled optically,
and BCS regime is achievable at realistic experimental conditions.


title:
The dichotomy between 'practical' and 'theoretical' astronomy in ancient
  and late antique literature

abstract:
  In Plato's dialogues Republic and Laws, the most important disciplines for
the best education of the rulers of the city are identified with arithmetic,
geometry and astronomy. Those disciplines, however, are not intended for
practical applications, but to reach the truth and see the form of good. In
particular, another dialogue, Epinomis, stresses on the relevance of astronomy
itself as main discipline, since it coincides with the study of the gods, that
is, the planets and the heaven. According to Epinomis, the wise astronomer does
not observe the risings and settings of stars for practical applications such
as the farmer calendar, but he studies the orbits of the planets. Therefore,
the 'practical' astronomy of farmers appears intrinsically less important than
the 'theoretical' one, i.e. the study of the planetary motions. We discuss the
possibly far-reaching negative implications of such a specific discrimination.
We report some examples taken from Greek and Latin literature illustrating the
difficulties of a coherent description of the risings and settings of stars
that was attempted by scholars, and should have been of little help for
farming. We conclude by pointing out the practical importance of astronomy
(intended in a broad sense) even today, and of the dangers of the separation or
discrimination of disciplines and sub-disciplines for the culture during the
present global economic crisis.


title:
Beyond unimodal regression: modelling multimodality with piecewise
  unimodal regression or deconvolution models

abstract:
  Shape constraints enable us to reflect prior knowledge in regression
settings. A unimodality constraint, for example, can describe the frequent case
of a first increasing and then decreasing intensity. Yet, data shapes often
exhibit multiple modes. Therefore, we go beyond unimodal regression and propose
modelling multimodality with piecewise unimodal regression or with
deconvolution models based on unimodal peak shapes. Usefulness of unimodal
regression and its multimodal extensions is demonstrated within three
applications areas: marine biology, astroparticle physics and breath gas
analysis. Despite this diversity, valuable results are obtained in each
application. This encourages the use of these methods in other areas as well.


title:
Tracking local magnetic dynamics via high-energy charge excitations in a
  relativistic Mott insulator

abstract:
  We use time- and energy-resolved optical spectroscopy to investigate the
coupling of electron-hole excitations to the magnetic environment in the
relativistic Mott insulator Na$_2$IrO$_3$. We show that, on the picosecond
timescale, the photoinjected electron-hole pairs delocalize on the hexagons of
the Ir lattice via the formation of quasi-molecular orbital (QMO) excitations
and the exchange of energy with the short-range-ordered zig-zag magnetic
background. The possibility of mapping the magnetic dynamics, which is
characterized by typical frequencies in the THz range, onto high-energy (1-2
eV) charge excitations provides a new platform to investigate, and possibly
control, the dynamics of magnetic interactions in correlated materials with
strong spin-orbit coupling, even in the presence of complex magnetic phases.


title:
Germanium under high tensile stress: nonlinear dependence of direct band
  gap vs. strain

abstract:
  Germanium is a strong candidate as a laser source for silicon photonics. It
is widely accepted that the band structure of germanium can be altered by
tensile strain so as to reduce the energy difference between its direct and
indirect band gaps. However, the conventional deformation potential model most
widely adopted to describe this transformation happens to have been
investigated only up to 1 % uniaxially loaded strains. In this work, we use a
micro-bridge geometry to uniaxially stress germanium along [100] up to
$\varepsilon_{100}$=3.3 % longitudinal strain and then perform
electro-absorption spectroscopy. We accurately measure the energy gap between
the conduction band at the $\Gamma$ point and the light- and heavy-hole valence
bands. While the experimental results agree with the conventional linear
deformation potential theory up to 2 % strain, a significantly nonlinear
behavior is observed at higher strains. We measure the deformation potential of
germanium to be a = -9.1 $\pm$ 0.3 eV and b = -2.32 $\pm$ 0.06 eV and introduce
a second order deformation potential. The experimental results are found to be
well described by tight-binding simulations. These new high strain coefficients
will be suitable for the design of future CMOS-compatible lasers and
opto-electronic devices based on highly strained germanium.


title:
Locally finite groups in which every non-cyclic subgroup is
  self-centralizing

abstract:
  Locally finite groups having the property that every non-cyclic subgroup
contains its centralizer are completely classified.


title:
Point kinetic model of the early phase of a spherically symmetric
  nuclear explosion

abstract:
  A concise point kinetic model of the explosion of a prompt supercritical
sphere driven by a nuclear fission chain reaction is presented. The findings
are in good agreement with the data available for Trinity, the first detonation
of a nuclear weapon conducted by the United States Army as part of the
Manhattan project. Results are presented for an implosion device containing
pure plutonium-239, although the model can be easily applied to, e.g.,
uranium-235. The fizzle probability and corresponding yield of a fission bomb
containing plutonium recovered from reactor fuel and therefore containing
significant amounts of spontaneously fissioning plutonium-240 which can induce
a predetonation of the device is illustrated by adding a corresponding source
term in the presented model. Related questions whether a bomb could be made by
developing countries or terrorist organizations can be tackled this way.
Although the information needed to answer such questions is in the public
domain, it is difficult to extract a consistent picture of the subject for
members of organizations who are concerned about the proliferation of nuclear
explosives.


title:
Trustworthy and Secure Service-Oriented Architecture for the Internet of
  Things

abstract:
  In the Internet of Things (IoT), heterogeneous devices connect to each other
and to external systems to exchange data and provide services. Given the
diversity of devices, it is becoming increasingly common to establish
collaborative relationships between devices to provide composite services.
However, due to the high degree of heterogeneity in the IoT context, one of the
most significant challenges is to develop software applications that can run on
a wide variety of devices and can communicate and collaborate with an even
wider array of systems. A common middleware infrastructure for these devices
will therefore have a significant impact on the design, deployment, and use of
services in IoT systems by allowing developers to focus on the applications
rather than the low-level implementation details each device.


title:
Predictive Coding for Dynamic Vision : Development of Functional
  Hierarchy in a Multiple Spatio-Temporal Scales RNN Model

abstract:
  The current paper presents a novel recurrent neural network model, the
predictive multiple spatio-temporal scales RNN (P-MSTRNN), which can generate
as well as recognize dynamic visual patterns in the predictive coding
framework. The model is characterized by multiple spatio-temporal scales
imposed on neural unit dynamics through which an adequate spatio-temporal
hierarchy develops via learning from exemplars. The model was evaluated by
conducting an experiment of learning a set of whole body human movement
patterns which was generated by following a hierarchically defined movement
syntax. The analysis of the trained model clarifies what types of
spatio-temporal hierarchy develop in dynamic neural activity as well as how
robust generation and recognition of movement patterns can be achieved by using
the error minimization principle.


title:
Relationship among various Vietoris-type and microsimplicial homology
  theories

abstract:
  In this paper, we clarify the relationship among the Vietoris-type homology
theories and the microsimplicial homology theories, where the latter are
nonstandard homology theories defined by M. C. McCord (for topological spaces),
T. Korppi (for completely regular topological spaces) and the author (for
uniform spaces). We show that McCord's and our homology are isomorphic for all
compact uniform spaces and that Korppi's and our homology are isomorphic for
all fine uniform spaces. Our homology shares many good properties with Korppi's
homology. As an example, we outline a proof of the continuity of our homology
with respect to uniform resolutions. S. Garavaglia proved that McCord's
homology is isomorphic to Vietoris homology for all compact topological spaces.
Inspired by this result, we prove that our homology is isomorphic to uniform
Vietoris homology for all precompact uniform spaces and that Korppi's homology
is isomorphic to normal Vietoris homology for all pseudocompact completely
regular topological spaces.


title: Phenomenological signatures of additional scalar bosons at the LHC

abstract:
  We investigate the search prospects for new scalars beyond the Standard Model
(SM) at the Large Hadron Collider (LHC). In these studies two real scalars $S$
and $\chi$ have been introduced in a two Higgs doublet model (2HDM), where $S$
is a portal to dark matter (DM) through its interaction with $\chi$, a DM
candidate and a possible source of missing transverse energy (\MET). Previous
studies focused on a heavy scalar $H$ decay mode $H \to h\chi\chi$, which was
studied using an effective theory in order to explain a distortion in the Higgs
($h$) transverse momentum spectrum [16]. In this work, the effective decay is
understood more deeply by including a mediator $S$, and the focus is changed to
$H \to h S,~SS$ with $S \to \chi\chi$. Phenomenological signatures of all the
new scalars in the proposed 2HDM are discussed in the energy regime of the LHC,
and their mass bounds have been set accordingly. Additionally, we have
performed several analyses with final states including leptons and \MET, with
$H \to 4 W$, $t\bar t H \to 6 W$ and $A \to ZH$ channels, in order to
understand the impact these scalars have on current searches.


title:
Solar cycle full-shape predictions: a global error evaluation for cycle
  24

abstract:
  There are many proposed prediction methods for solar cycles behavior. In a
previous paper we updated the full-shape curve prediction of the current solar
cycle 24 using a non-linear dynamics method and we compared the results with
the predictions collected by the NOAA/SEC prediction panel, using observed data
up to October 2010. The aim of the present paper is to give a quantitative
evaluation, a posteriori, of the performances of these prediction methods using
a specific global error, updated on a monthly basis, which is a measure of the
global performance on the predicted shape (both amplitude and phase) of the
solar cycle. We suggest also the use of a percent cycle similarity degree, to
better evaluate the predicted shape of the solar cycle curve.


title: Detection of tau neutrinos by Imaging Air Cherenkov Telescopes

abstract:
  This paper investigates the potential to detect tau neutrinos in the energy
range of 1-1000 PeV searching for very inclined showers with imaging Cherenkov
telescopes. A neutrino induced tau lepton escaping from the Earth may decay and
initiate an air shower which can be detected by a fluorescence or Cherenkov
telescope. We present here a study of the detection potential of Earth-skimming
neutrinos taking into account neutrino interactions in the Earth crust, local
matter distributions at various detector sites, the development of tau-induced
showers in air and the detection of Cherenkov photons with IACTs. We analyzed
simulated shower images on the camera focal plane and implemented generic
reconstruction chains based on Hillas parameters. We find that present IACTs
can distinguish air showers induced by tau neutrinos from the background of
hadronic showers in the PeV-EeV energy range. We present the neutrino trigger
efficiency obtained for a few configurations being considered for the
next-generation Cherenkov telescopes, i.e. the Cherenkov Telescope Array.
Finally, for a few representative neutrino spectra expected from astrophysical
sources, we compare the expected event rates at running IACTs to what is
expected for the dedicated IceCube neutrino telescope.


title: Electron motion enhanced high harmonic generation in xenon clusters

abstract:
  Atomic clusters presents an isolated system that models the bulk materials
whose mechanism of HHG remains uncertain, and a promising medium to produce HHG
beyond the limited conversion efficiency for gaseous atoms. Here we reveal that
the oscillation of collective electron motion within clusters develops after
the interaction of intense laser fields, and it significantly enhances the
harmonic dipole and increases the quantum phase of the harmonics.
Experimentally, the phase matching conditions of HHG from nanometer xenon
clusters and atoms are distinguished, which confirms the enhanced internal
field that was proposed theoretically a decade ago. The separation of HHG from
atoms and clusters allows the determination of the amplitude of the HHG for
clusters to be 5 orders higher, corresponding to 4 times higher conversion
efficiency for atomic response. The finding provides an insight on the HHG
mechanism of bulk materials and a means by which an efficient coherent X-ray
source can be developed.


title:
Extensive Characterization of Seismic Laws in Acoustic Emissions of
  Crumpled Plastic Sheets

abstract:
  Statistical similarities between earthquakes and other systems that emit
cracking noises have been explored in diverse contexts, ranging from materials
science to financial and social systems. Such analogies give promise of a
unified and universal theory for describing the complex responses of those
systems. There are, however, very few attempts to simultaneously characterize
the most fundamental seismic laws in such systems. Here we present a complete
description of the Gutenberg-Richter law, the recurrence times, Omori's law,
the productivity law, and Bath's law for the acoustic emissions that happen in
the relaxation process of uncrumpling thin plastic sheets. Our results show
that these laws also appear in this phenomenon, but (for most cases) with
different parameters from those reported for earthquakes and fracture
experiments. This study thus contributes to elucidate the parallel between
seismic laws and cracking noises in uncrumpling processes, revealing striking
qualitative similarities but also showing that these processes display unique
features.

categories: physics.geo-ph cond-mat.mtrl-sci cond-mat.stat-mech physics.data-an


title: The double gluon distribution from the single gluon distribution

abstract:
  Using momentum sum rule for evolution equations for Double Parton
Distribution Functions (DPDFs) in the leading logarithmic approximation, we
find that the double gluon distribution function can be uniquely constrained
via the single gluon distribution function. We also study numerically its
evolution with a hard scale and show that an approximately factorized ansatz
into the product of two single gluon distributions performs quite well at small
values of $x$ but is always violated for larger values, as expected.


title: How many matrices can be spectrally balanced simultaneously?

abstract:
  We prove that any $\ell$ positive definite $d \times d$ matrices,
$M_1,\ldots,M_\ell$, of full rank, can be simultaneously spectrally balanced in
the following sense: for any $k < d$ such that $\ell \leq \lfloor
\frac{d-1}{k-1} \rfloor$, there exists a matrix $A$ satisfying
$\frac{\lambda_1(A^T M_i A) }{ \mathrm{Tr}( A^T M_i A ) } < \frac{1}{k}$ for
all $i$, where $\lambda_1(M)$ denotes the largest eigenvalue of a matrix $M$.
This answers a question posed by Peres, Popov and Sousi and completes the
picture described in that paper regarding sufficient conditions for transience
of self-interacting random walks. Furthermore, in some cases we give
quantitative bounds on the transience of such walks.


title:
Magnetic field effects in a correlated electron system with spin-state
  degree of freedom - Implication of an excitonic insulator -

abstract:
  Magnetic field (H) effects on a correlated electron system with the
spin-state degree of freedom are examined. The effective Hamiltonian derived
from the two-orbital Hubbard model is analyzed by the mean-field approximation.
Applying H to the low-spin (LS) phase induces the excitonic insulating phase,
as well as the spin-state ordered phase where the LS and high-spin (HS) states
are ordered alternately. In the case where H is applied to the HS phase, a
reentrant transition for the HS phase appears. A rich variety of the phase
diagrams are attributed to the spin-state degree of freedom and their
combinations in the wave function as well as in the real-space configuration.


title:
Spontaneous collapse: a solution to the measurement problem and a source
  of the decay in mesonic systems

abstract:
  Dynamical reduction models propose a solution to the measurement problem in
quantum mechanics: the collapse of the wave function becomes a physical
process. We compute the predictions to decaying and Dynamical reduction models
propose a solution to the measurement problem in quantum mechanics: the
collapse of the wave function becomes a physical process. We compute the
predictions to decaying and flavor--oscillating neutral mesons for the two most
promising collapse models, the QMUPL (Quantum Mechanics with Universal Position
Localization) model and the mass-proportional CSL (Continuous Spontaneous
Localization) model. Our results are showing (i) a strong sensitivity to the
very assumptions of the noise field underlying those two collapse models and
(ii) under particular assumptions the CSL case allows even to recover the decay
dynamics. This in turn allows to predict the effective collapse rates solely
based on the measured values for the oscillation (mass differences) and the
measured values of the decay constants. The four types of neutral mesons
($K$-meson, $D$-meson, $B_d$-meson, $B_s$-meson) lead surprisingly to ranges
comparable to those put forward by Adler (2007) and Ghirardi-Rimini-Weber
(1986). Our results show that these systems at high energies are very sensitive
to possible modifications of the standard quantum theory making them a very
powerful laboratory to rule out certain collapse scenarios and studying the
detailed physical processes solving the measurement problem.


title: Excitons and optical spectra of phosphorene nanoribbons

abstract:
  On the basis of many-body {\it ab-initio} calculations, using single-shot
G$_0$W$_0$ method and Bethe-Salpeter equation, we study phosphorene nanoribbons
(PNRs) in the two typical zigzag and armchair directions. The electronic
structure, optical absorption, electron-hole (exciton) binding energy, exciton
exchange splitting, and exciton wave functions are calculated for different
size of PNRs. The typically strong splitting between singlet and triplet
excitonic states make PNRs favorable systems for application in optoelectronic.
Quantum confinement occurs in both kinds of PNRs, and it is stronger in the
zPNRs, as behave like quasi-zero-dimensional systems. Scaling laws are
investigated for the size-dependent behaviors of PNRs. The first bright
excitonic state in PNRs is explored in detail.


title: Regulation of Irregular Neuronal Firing by Autaptic Transmission

abstract:
  The importance of self-feedback autaptic transmission in modulating
spike-time irregularity is still poorly understood. By using a biophysical
model that incorporates autaptic coupling, we here show that self-innervation
of neurons participates in the modulation of irregular neuronal firing,
primarily by regulating the occurrence frequency of burst firing. In
particular, we find that both excitatory and electrical autapses increase the
occurrence of burst firing, thus reducing neuronal firing regularity. In
contrast, inhibitory autapses suppress burst firing and therefore tend to
improve the regularity of neuronal firing. Importantly, we show that these
findings are independent of the firing properties of individual neurons, and as
such can be observed for neurons operating in different modes. Our results
provide an insightful mechanistic understanding of how different types of
autapses shape irregular firing at the single-neuron level, and they highlight
the functional importance of autaptic self-innervation in taming and modulating
neurodynamics.


title: Suprathermal electrons at Saturn's bow shock

abstract:
  The leading explanation for the origin of galactic cosmic rays is particle
acceleration at the shocks surrounding young supernova remnants (SNRs),
although crucial aspects of the acceleration process are unclear. The similar
collisionless plasma shocks frequently encountered by spacecraft in the solar
wind are generally far weaker (lower Mach number) than these SNR shocks.
However, the Cassini spacecraft has shown that the shock standing in the solar
wind sunward of Saturn (Saturn's bow shock) can occasionally reach this
high-Mach number astrophysical regime. In this regime Cassini has provided the
first in situ evidence for electron acceleration under quasi-parallel upstream
magnetic conditions. Here we present the full picture of suprathermal electrons
at Saturn's bow shock revealed by Cassini. The downstream thermal electron
distribution is resolved in all data taken by the low-energy electron detector
(CAPS-ELS, <28 keV) during shock crossings, but the higher energy channels were
at (or close to) background. The high-energy electron detector (MIMI-LEMMS, >18
keV) measured a suprathermal electron signature at 31 of 508 crossings, where
typically only the lowest energy channels (<100 keV) were above background. We
show that these results are consistent with theory in which the "injection" of
thermal electrons into an acceleration process involves interaction with
whistler waves at the shock front, and becomes possible for all upstream
magnetic field orientations at high Mach numbers like those of the strong
shocks around young SNRs. A future dedicated study will analyze the rare
crossings with evidence for relativistic electrons (up to ~1 MeV).


title: Tessellations derived from random geometric graphs

abstract:
  In this paper we consider a random partition of the plane into cells, the
partition being based on the nodes and links of a {\it random planar geometric
graph}. The resulting structure generalises the \emph{random \tes}\ hitherto
studied in the literature. The cells of our partition process, possibly with
holes and not necessarily closed, have a fairly general topology summarised by
a functional which is similar to the Euler characteristic. The functional can
also be extended to certain cell-unions which can arise in applications.
Vertices of all valencies, $0, 1, 2, ...$ are allowed. Many of the formulae
from the traditional theory of random tessellations with convex cells, are made
more general to suit this new structure. Some motivating examples of the
structure are given.


title: Moments estimates for local times of one class of Gaussian processes

abstract:
  In present paper we prove an existence and give a moments estimate for the
local time of Gaussian integrators. Every Gaussian integrator is associated
with a continuous linear operator in the space of square integrable functions
via white noise representation. Hence, all properties of such process are
completely characterized by properties of the corresponding operator. We
describe the sufficient conditions on continuous linear non-invertible operator
which allow the local time of the integrator to exists at any real point.
Moments estimate for local time is obtained. A continuous dependence of local
time of Gaussian integrators on generating them operators is established. The
received statement improves our result presented in [1].


title: Influence of trust in the spreading of information

abstract:
  The understanding and prediction of information diffusion processes on
networks is a major challenge in network theory with many implications in
social sciences. Many theoretical advances occurred due to stochastic spreading
models. Nevertheless, these stochastic models overlooked the influence of
rational decisions on the outcome of the process. For instance, different
levels of trust in acquaintances do play a role in information spreading, and
actors may change their spreading decisions during the information diffusion
process accordingly. Here, we study an information-spreading model in which the
decision to transmit or not is based on trust. We explore the interplay between
the propagation of information and the trust dynamics happening on a two-layer
multiplex network. Actors' trustable or untrustable states are defined as
accumulated cooperation or defection behaviors, respectively, in a Prisoner's
Dilemma set up, and they are controlled by a memory span. The propagation of
information is abstracted as a threshold model on the information-spreading
layer, where the threshold depends on the trustability of agents. The analysis
of the model is performed using a tree approximation and validated on
homogeneous and heterogeneous networks. The results show that the memory of
previous actions has a significant effect on the spreading of information. For
example, the less memory that is considered, the higher is the diffusion.
Information is highly promoted by the emergence of trustable acquaintances.
These results provide insight into the effect of plausible biases on spreading
dynamics in a multilevel networked system.


title:
Information Rates of Next-Generation Long-Haul Optical Fiber Systems
  Using Coded Modulation

abstract:
  A comprehensive study of the coded performance of long-haul
spectrally-efficient WDM optical fiber transmission systems with different
coded modulation decoding structures is presented. Achievable information rates
are derived for three different square QAM formats and the optimal format is
identified as a function of distance and specific decoder implementation. The
four cases analyzed combine hard-decision (HD) or soft-decision (SD) decoding
together with either a bit-wise or a symbol-wise demapper, the last two
suitable for binary and nonbinary codes, respectively. The information rates
achievable for each scheme are calculated based on the mismatched decoder
principle. These quantities represent true indicators of the coded performance
of the system for specific decoder implementations and when the modulation
format and its input distribution are fixed. In combination with the structure
of the decoder, two different receiver-side equalization strategies are also
analyzed: electronic dispersion compensation and digital backpropagation. We
show that, somewhat unexpectedly, schemes based on nonbinary HD codes can
achieve information rates comparable to SD decoders and that, when SD is used,
switching from a symbol-wise to a bit-wise decoder results in a negligible
penalty. Conversely, from an information-theoretic standpoint, HD binary
decoders are shown to be unsuitable for spectrally-efficient, long-haul
systems.