title:
Absorption Line Spectroscopy of Gravitationally-Lensed Galaxies: Further
  Constraints on the Escape Fraction of Ionizing Photons at High Redshift

abstract:
  The fraction of ionizing photons escaping from high-redshift star-forming
galaxies remains a key obstacle in evaluating whether galaxies were the primary
agents of cosmic reionization. We previously proposed using the covering
fraction of low-ionization gas, measured via deep absorption line spectroscopy,
as a proxy. We now present a significant update, sampling seven
gravitationally-lensed sources at $4<z<5$. We show that the absorbing gas in
our sources is spatially inhomogeneous with a median covering fraction of 66\%.
Correcting for reddening according to a dust-in-cloud model, this implies an
estimated absolute escape fraction of $\simeq19\pm6$\%. With possible biases
and uncertainties, collectively we find the average escape fraction could be
reduced to no less than 11\%, excluding the effect of spatial variations. For
one of our lensed sources, we have sufficient signal/noise to demonstrate the
presence of such spatial variations and scatter in its dependence on the
Ly$\alpha$ equivalent width, consistent with recent simulations. If this source
is typical, our lower limit to the escape fraction could be reduced by a
further factor $\simeq$2. Across our sample, we find a modest anti-correlation
between the inferred escape fraction and the local star formation rate,
consistent with a time delay between a burst and leaking Lyman continuum
photons. Our analysis demonstrates considerable variations in the escape
fraction consistent with being governed by the small-scale behavior of
star-forming regions, whose activities fluctuate over short timescales. This
supports the suggestion that the escape fraction may increase toward the
reionization era when star formation becomes more energetic and burst-like.


title: Holistic Features For Real-Time Crowd Behaviour Anomaly Detection

abstract:
  This paper presents a new approach to crowd behaviour anomaly detection that
uses a set of efficiently computed, easily interpretable, scene-level holistic
features. This low-dimensional descriptor combines two features from the
literature: crowd collectiveness [1] and crowd conflict [2], with two newly
developed crowd features: mean motion speed and a new formulation of crowd
density. Two different anomaly detection approaches are investigated using
these features. When only normal training data is available we use a Gaussian
Mixture Model (GMM) for outlier detection. When both normal and abnormal
training data is available we use a Support Vector Machine (SVM) for binary
classification. We evaluate on two crowd behaviour anomaly detection datasets,
achieving both state-of-the-art classification performance on the violent-flows
dataset [3] as well as better than real-time processing performance (40 frames
per second).


title: On Monotonic Fixed-Point Free Bijections on Subgroups of $\mathbb R$

abstract:
  We show that for any continuous monotonic fixed-point free automorphism $f$
on a $\sigma$-compact subgroup $G\subset \mathbb R$ there exists a binary
operation $+_f$ such that $\langle G, +_f\rangle$ is a topological group
topologically isomorphic to $\langle G, +\rangle$ and $f$ is a shift with
respect to $+_f$. We then show that monotonicity cannot be replaced by the
property of being periodic-point free. We explore a few routes leading to
generalizations and counterexamples.


title: Successor Features for Transfer in Reinforcement Learning

abstract:
  Transfer in reinforcement learning refers to the notion that generalization
should occur not only within a task but also across tasks. We propose a
transfer framework for the scenario where the reward function changes between
tasks but the environment's dynamics remain the same. Our approach rests on two
key ideas: "successor features", a value function representation that decouples
the dynamics of the environment from the rewards, and "generalized policy
improvement", a generalization of dynamic programming's policy improvement
operation that considers a set of policies rather than a single one. Put
together, the two ideas lead to an approach that integrates seamlessly within
the reinforcement learning framework and allows the free exchange of
information across tasks. The proposed method also provides performance
guarantees for the transferred policy even before any learning has taken place.
We derive two theorems that set our approach in firm theoretical ground and
present experiments that show that it successfully promotes transfer in
practice, significantly outperforming alternative methods in a sequence of
navigation tasks and in the control of a simulated robotic arm.


title:
Unsupervised Risk Estimation Using Only Conditional Independence
  Structure

abstract:
  We show how to estimate a model's test error from unlabeled data, on
distributions very different from the training distribution, while assuming
only that certain conditional independencies are preserved between train and
test. We do not need to assume that the optimal predictor is the same between
train and test, or that the true distribution lies in any parametric family. We
can also efficiently differentiate the error estimate to perform unsupervised
discriminative learning. Our technical tool is the method of moments, which
allows us to exploit conditional independencies in the absence of a
fully-specified model. Our framework encompasses a large family of losses
including the log and exponential loss, and extends to structured output
settings such as hidden Markov models.


title:
A few remarks on the relationship between elementary particle physics,
  gravitation and cosmology

abstract:
  We discuss some current problems in the relationship between elementary
particle physics and gravitation, i.e., in the subject investigated by
Prof.~K.~P.~Staniukovich half a century ago. Specifically, the inflationary
stage of the Universe evolution, originating from the vacuum polarization and
particle creation, corrections to Newton's gravitational law due to exchange of
light elementary particles or spontaneous compactification of extra dimensions,
and constraints on the parameters of axions as probable constituents of dark
matter in our Universe are considered. It is pointed out that presently the
relationship between elementary particles and gravitation has become an
experimental science, and many experiments, directed towards resolution of all
related problems, are performed in many countries.


title: Global minimizers of the Allen-Cahn equation in dimension $n\geq 8$

abstract:
  We prove the existence of global minimizers of Allen-Cahn equation in
dimensions $8$ and above. More precisely, given any strictly area-minimizing
Lawson's cones, there are global minimizers whose nodal sets are asymptotic to
the cones. As a consequence of Jerison-Monneau's program we establish the
existence of many counter-examples to the De Giorgi's conjecture different from
the Bombierie-De Giorgi-Giusti minimal graph.


title: Learning Infinite-Layer Networks: Without the Kernel Trick

abstract:
  Infinite--Layer Networks (ILN) have recently been proposed as an architecture
that mimics neural networks while enjoying some of the advantages of kernel
methods. ILN are networks that integrate over infinitely many nodes within a
single hidden layer. It has been demonstrated by several authors that the
problem of learning ILN can be reduced to the kernel trick, implying that
whenever a certain integral can be computed analytically they are efficiently
learnable.
  In this work we give an online algorithm for ILN, which avoids the kernel
trick assumption. More generally and of independent interest, we show that
kernel methods in general can be exploited even when the kernel cannot be
efficiently computed but can only be estimated via sampling.
  We provide a regret analysis for our algorithm, showing that it matches the
sample complexity of methods which have access to kernel values. Thus, our
method is the first to demonstrate that the kernel trick is not necessary as
such, and random features suffice to obtain comparable performance.


title:
A New Approach to P\'olya Urn Schemes and Its Infinite Color
  Generalization

abstract:
  In this work we generalize Polya urn schemes with possibly infinitely many
colors and extend the earlier models described in [4, 5, 7]. We provide a novel
and unique approach of representing the observed sequence of colors in terms a
branching Markov chain on random recursion tree. This enables us to derive
fairly general asymptotic for our urn schemes. We then illustrate through
several examples that our method can easily derive the classical results for
finite urns, as well as, many new results for infinite color urns.


title: Toward the intrinsic limit of topological insulator Bi2Se3

abstract:
  Combining high resolution scanning tunneling microscopy and first principle
calculations, we identified the major native defects, in particular the Se
vacancies and Se interstitial defects that are responsible for the bulk
conduction and nanoscale potential fluctuation in single crystals of archetypal
topological insulator Bi2Se3. Here it is established that the defect
concentrations in Bi2Se3 are far above the thermodynamic limit, and that the
growth kinetics dominate the observed defect concentrations. Furthermore,
through careful control of the synthesis, our tunneling spectroscopy suggests
that our best samples are approaching the intrinsic limit with the Fermi level
inside the band gap without introducing extrinsic dopants.


title:
Potential improvement for elastocaloric performances of shape memory
  alloys through comparing with natural rubber

abstract:
  The elastocaloric (eC) effects of natural rubber (NR) and shape memory alloys
(SMAs) are compared and potential improvement for eC performances of SMAs is
proposed. Both the plateau and hysteresis of stress-strain curve in NR and SMAs
are observed. They are attributed to the similar phase transformation:
strain-induced crystallization (SIC) in NR and martensitic transformation in
SMAs. For NR, the drawback of large strain can be reduced by pre-strain. For
SMAs, the stress change with strain is smaller in stress plateau regime. Thus,
the drawback of large dynamic stress of SMAs is proposed to be reduced by a
static pre-stress for working directly in this stress plateau regime. Choosing
an appropriate pre-strain (pre-stress) and strain amplitude can make eC effect
of NR working in the phase transformation (SIC) regime. This method can improve
both the eC strength and fatigue life in NR. Due to the similar phase
transformation (martensitic transformation) of SMAs to NR, this method is also
proposed to improve the eC performances of SMAs.


title:
Increasing the Interpretability of Recurrent Neural Networks Using
  Hidden Markov Models

abstract:
  As deep neural networks continue to revolutionize various application
domains, there is increasing interest in making these powerful models more
understandable and interpretable, and narrowing down the causes of good and bad
predictions. We focus on recurrent neural networks (RNNs), state of the art
models in speech recognition and translation. Our approach to increasing
interpretability is by combining an RNN with a hidden Markov model (HMM), a
simpler and more transparent model. We explore various combinations of RNNs and
HMMs: an HMM trained on LSTM states; a hybrid model where an HMM is trained
first, then a small LSTM is given HMM state distributions and trained to fill
in gaps in the HMM's performance; and a jointly trained hybrid model. We find
that the LSTM and HMM learn complementary information about the features in the
text.


title: Cubic fourfolds fibered in sextic del Pezzo surfaces

abstract:
  We exhibit new examples of rational cubic fourfolds, parametrized by a
countably infinite union of codimension-two subvarieties in the moduli space.
Our examples are fibered in sextic del Pezzo surfaces over the projective
plane; they are rational whenever the fibration has a rational section.


title:
Structure and dynamics of H$_2^+$ near the dissociation threshold: a
  combined experimental and computational investigation

abstract:
  The pulsed-field-ionization zero-kinetic-energy photoelectron spectrum of
H$_2$ has been recorded in the vicinity of the dissociative-ionization
threshold following three-photon excitation via selected rotational levels of
the B $^1\Sigma_u^+$ ($v=19$) and $\bar{\rm H}$ $^1\Sigma_g^+$ ($v=11$)
intermediate states. The spectra consist of transitions to bound levels of the
X$^+$ $^2\Sigma_g^+$ state of H$_2^+$ with $v^+$ in the range 14-19 and $N^+$
in the range 0-9, of the A$^+$ $^2\Sigma_u^+$ state with $v^+=0$ and $N^+=0-2$,
and of shape resonances corresponding to the X$^+\ (v^+=17,N^+=7)$ and X$^+\
(v^+=18,N^+=4)$ quasibound levels. Calculations of the level structure of
H$_2^+$ have been carried out and the influence of adiabatic, nonadiabatic,
relativistic and radiative corrections on the positions of these levels, and in
the case of the shape resonances also on their widths, has been investigated.
Different methods of calculating the widths and profiles of the shape
resonances have been tested for comparison with the experimental observations.
Slow oscillations of the dissociative-ionization yield have been observed and
reflect, in first approximation, the Franck-Condon factors of the $\bar{\text
H}$ $\rightarrow$ X$^+$, A$^+$ bound - free transitions.


title: Dynamics of detonations with a constant mean flow divergence

abstract:
  An exponential horn geometry is introduced in order to establish cellular
detonations with a constant mean lateral mass divergence, propagating at
quasi-steady speeds below the Chapman-Jouguet value. Experiments and
simulations demonstrated that such quasi-steady state detonations can be
realized, hence permitting to obtain the relations between the detonation speed
and mean lateral flow divergence for cellular detonations in an unambiguous
manner. The experimentally obtained speed ($D$) dependencies on divergence
($K$) were compared with the predictions for steady detonations with lateral
flow divergence obtained with the real thermo-chemical data of the mixtures.
For the 2C$_2$H$_2$+5O$_2$+21Ar system, reasonable agreement was found between
the experiments and steady wave prediction, particularly for the critical
divergence leading to failure. Observations of the reaction zone structure in
these detonations indicated that all the gas reacted very close to the front,
as the transverse waves were reactive. The experiments obtained in the much
more unstable detonations in C$_3$H$_8$+5O$_2$ showed significant differences
between the experimentally derived $D(K)$ curve and the prediction of steady
wave propagation. The latter was found to significantly under-predict the
detonability of cellular detonations. The transverse waves in this mixture were
found to be non-reactive, hence permitting to shed off non-reacted pockets,
which burn via turbulent flames on their surface. It is believed that the large
differences between experiment and the inviscid model in this class of cellular
structures is due to the importance of diffusive processes in the burn-out of
the non-reacted pockets.


title: On new exact conformal blocks and Nekrasov functions

abstract:
  Recently, an intriguing family of the one-point toric conformal blocks AGT
related to the $\mathcal{N}=2^*\,\, SU(2)$ Nekrasov functions was discovered by
M. Beccaria and G. Macorini. Members of the family are distinguished by having
only finite amount of poles as functions of the intermediate dimension/v.e.v.
in gauge theory. Another remarkable property is that these conformal
blocks/Nekrasov functions can be found in closed form to all orders in the
coupling expansion. In the present paper we use Zamolodchikov's recurrence
equation to systematically account for these exceptional conformal blocks. We
conjecture that the family is infinite-dimensional and describe the
corresponding parameter set. We further apply the developed technique to
demonstrate that the four-point spheric conformal blocks feature analogous
exact expressions. We also study the modular transformations of the finite-pole
blocks.


title: ACDC: $\alpha$-Carving Decision Chain for Risk Stratification

abstract:
  In many healthcare settings, intuitive decision rules for risk stratification
can help effective hospital resource allocation. This paper introduces a novel
variant of decision tree algorithms that produces a chain of decisions, not a
general tree. Our algorithm, $\alpha$-Carving Decision Chain (ACDC),
sequentially carves out "pure" subsets of the majority class examples. The
resulting chain of decision rules yields a pure subset of the minority class
examples. Our approach is particularly effective in exploring large and
class-imbalanced health datasets. Moreover, ACDC provides an interactive
interpretation in conjunction with visual performance metrics such as Receiver
Operating Characteristics curve and Lift chart.


title: A 750 GeV graviton and the Higgs as a pNGB

abstract:
  We study the diphoton excess at 750 GeV reported by ATLAS and CMS, by
assuming that it corresponds to a new spin-two resonant state. We model this
state as a massive graviton in a two-site model. We show that the very
stringent bounds from $VV$ final states can be evaded naturally by considering
that the Higgs is a pseudo Nambu-Goldstone boson. In this case the couplings of
the graviton to the longitudinal electroweak gauge bosons can be parametrically
suppressed. On the other hand, partial compositeness allows to suppress the
leptonic channels. We compute loop-induced contributions to the graviton
couplings by the presence of the SM third generation of quarks and composite
partners of the SM fermions and obtain that they are not important. We find
that the diphoton signal and the experimental constraints from other decay
channels can be reproduced in a large and natural region of the parameter space
of the theory.


title: Floer homology of Lagrangians in clean intersection

abstract:
  We consider Floer homology associated to a pair of closed Lagrangian
submanifolds that satisfy a monotonicty assumption. If the Lagrangians
intersect cleanly we decribe two spectral sequences which help to compute their
Floer homology. The spectral sequences are constructed using a Morse-Bott
version of Floer homology. We give a full treatment of the theory including
orientations.


title: Conditional Image Generation with PixelCNN Decoders

abstract:
  This work explores conditional image generation with a new image density
model based on the PixelCNN architecture. The model can be conditioned on any
vector, including descriptive labels or tags, or latent embeddings created by
other networks. When conditioned on class labels from the ImageNet database,
the model is able to generate diverse, realistic scenes representing distinct
animals, objects, landscapes and structures. When conditioned on an embedding
produced by a convolutional network given a single image of an unseen face, it
generates a variety of new portraits of the same person with different facial
expressions, poses and lighting conditions. We also show that conditional
PixelCNN can serve as a powerful decoder in an image autoencoder. Additionally,
the gated convolutional layers in the proposed model improve the log-likelihood
of PixelCNN to match the state-of-the-art performance of PixelRNN on ImageNet,
with greatly reduced computational cost.


title: 125 GeV Higgs boson mass and muon g-2 in 5D MSSM

abstract:
  In the MSSM, the tension between the observed Higgs boson mass and the
experimental result of the muon $g-2$ measurement requires a large mass
splitting between stops and smuons/charginos/neutralinos. We consider a
5-dimensional (5D) framework of the MSSM with the Randall-Sundrum warped
background metric, and show that such a mass hierarchy is naturally achieved in
terms of geometry. In our setup, the supersymmetry is broken at the ultraviolet
(UV) brane, while all the MSSM multiplets reside in the 5D bulk. An appropriate
choice of the bulk mass parameters for the MSSM matter multiplets can naturally
realize the sparticle mass hierarchy desired to resolve the tension. Gravitino
is localized at the UV brane and hence becomes very heavy, while the gauginos
spreading over the bulk acquire their masses suppressed by the 5th dimensional
volume. As a result, the LSP neutralino is a candidate for the dark matter as
usual in the MSSM. In addition to reproducing the SM-like Higgs boson mass of
around 125 GeV and the measured value of the muon $g-2$, we consider a variety
of phenomenological constraints, and present the benchmark particle mass
spectra which can be explored at the LHC Run-2 in the near future.


title:
Irreducible Truth-Value Algebras Suffice for the Completeness of Many
  First-Order Algebraic Logics

abstract:
  It is well-known that a Hilbert-style deduction system for first-order
classical logic is sound and complete for a model theory built using all
Boolean algebras as truth-value algebras if and only if it is sound and
complete for a model theory utilizing only irreducible Boolean algebras (which
are all isomorphic to the two-element Boolean algebra). In this paper, we prove
an analogous result for any first-order logic with an algebraic semantics
satisfying certain minimal assumptions, and we then apply our result to
first-order quantum logic.


title: The Pattern Basis Approach to Circuit Complexity

abstract:
  We describe and motivate a proposed new approach to lowerbounding the circuit
complexity of boolean functions, based on a new formalization of "patterns" as
elements of a special basis of the vector space of all truth table properties.
We prove that a "pattern basis" with certain properties would lead to a useful
complexity formula of a specific form, and speculate on how to find such a
basis. This formula might take as long to compute on arbitrary functions as a
brute-force search among circuits, thus addressing the natural proofs barrier,
but has a form amenable to proving lower bounds for well-understood explicit
functions.


title:
Spatio-temporal Interference Correlation and Joint Coverage in Cellular
  Networks

abstract:
  This paper provides an analytical framework with foundations in stochastic
geometry to characterize the spatio-temporal interference correlation as well
as the joint coverage probability at two spatial locations in a cellular
network. In particular, modeling the locations of cellular base stations (BSs)
as a Poisson Point Process (PPP), we study interference correlation at two
spatial locations $\ell_1$ and $\ell_2$ separated by a distance $v$, when the
user follows \emph{closest BS association policy} at both spatial locations and
moves from $\ell_1$ to $\ell_2$. With this user displacement, two scenarios can
occur: i) the user is handed off to a new serving BS at $\ell_2$, or ii) no
handoff occurs and the user is served by the same BS at both locations. After
providing intermediate results such as probability of handoff and distance
distributions of the serving BS at the two user locations, we use them to
derive exact expressions for spatio-temporal interference correlation
coefficient and joint coverage probability for any distance separation $v$. We
also study two different handoff strategies: i) \emph{handoff skipping}, and
ii) \emph{conventional handoffs}, and derive the expressions of joint coverage
probability for both strategies. The exact analysis is not straightforward and
involves a careful treatment of the neighborhood of the two spatial locations
and the resulting handoff scenarios. To provide analytical insights, we also
provide easy-to-use expressions for two special cases: i) static user ($v =0$)
and ii) highly mobile user ($v \rightarrow \infty)$. As expected, our analysis
shows that the interference correlation and joint coverage probability decrease
with increasing $v$, with $v \rightarrow \infty$ corresponding to a completely
uncorrelated scenario.


title:
Bayesian dimensionality reduction with PCA using penalized
  semi-integrated likelihood

abstract:
  We discuss the problem of estimating the number of principal components in
Principal Com- ponents Analysis (PCA). Despite of the importance of the problem
and the multitude of solutions proposed in the literature, it comes as a
surprise that there does not exist a coherent asymptotic framework which would
justify different approaches depending on the actual size of the data set. In
this paper we address this issue by presenting an approximate Bayesian approach
based on Laplace approximation and introducing a general method for building
the model selection criteria, called PEnalized SEmi-integrated Likelihood
(PESEL). Our general framework encompasses a variety of existing approaches
based on probabilistic models, like e.g. Bayesian Information Criterion for the
Probabilistic PCA (PPCA), and allows for construction of new criteria,
depending on the size of the data set at hand. Specifically, we define PESEL
when the number of variables substantially exceeds the number of observations.
We also report results of extensive simulation studies and real data analysis,
which illustrate good properties of our proposed criteria as compared to the
state-of- the-art methods and very recent proposals. Specifially, these
simulations show that PESEL based criteria can be quite robust against
deviations from the probabilistic model assumptions. Selected PESEL based
criteria for the estimation of the number of principal components are
implemented in R package varclust, which is available on github
(https://github.com/psobczyk/varclust).


title:
Pinning of fermionic occupation numbers: Higher spatial dimensions and
  spin

abstract:
  The role of the generalized Pauli constraints (GPCs) in higher spatial
dimensions and by incorporating spin degrees of freedom is systematically
explored for a system of interacting fermions confined by a harmonic trap.
Physical relevance of the GPCs is confirmed by analytical means for the ground
state in the regime of weak couplings by finding its vector of natural
occupation numbers close to the boundary of the allowed region. Such
quasipinning is found to become weaker in the intermediate and strong coupling
regime. The study of crossovers between different spatial dimensions by
detuning the harmonic trap frequencies suggests that quasipinning is
essentially an effect for systems with reduced spatial dimensionality. In
addition, we find that quasipinning becomes stronger by increasing the degree
of spin-polarization. Consequently, the number of states available around the
Fermi level plays a key role for the occurrence of quasipinning. This suggests
that quasipinning emerges from the conflict between energy minimization and
fermionic exchange symmetry.


title: Parisi formula for the ground state energy in the mixed p-spin model

abstract:
  We show that the thermodynamic limit of the ground state energy in the mixed
p-spin model can be identified as a variational problem. This gives a natural
generalization of the Parisi formula at zero temperature.


title: On the Expressive Power of Deep Neural Networks

abstract:
  We propose a new approach to the problem of neural network expressivity,
which seeks to characterize how structural properties of a neural network
family affect the functions it is able to compute. Our approach is based on an
interrelated set of measures of expressivity, unified by the novel notion of
trajectory length, which measures how the output of a network changes as the
input sweeps along a one-dimensional path. Our findings can be summarized as
follows:
  (1) The complexity of the computed function grows exponentially with depth.
  (2) All weights are not equal: trained networks are more sensitive to their
lower (initial) layer weights.
  (3) Regularizing on trajectory length (trajectory regularization) is a
simpler alternative to batch normalization, with the same performance.


title: Calibration of weak-lensing shear in the Kilo-Degree Survey

abstract:
  We describe and test the pipeline used to measure the weak lensing shear
signal from the Kilo Degree Survey (KiDS). It includes a novel method of
`self-calibration' that partially corrects for the effect of noise bias. We
also discuss the `weight bias' that may arise in optimally-weighted
measurements, and present a scheme to mitigate that bias. To study the residual
biases arising from both galaxy selection and shear measurement, and to derive
an empirical correction to reduce the shear biases to $\lesssim 1\%$, we create
a suite of simulated images whose properties are close to those of the KiDS
survey observations. We find that the use of `self-calibration' reduces the
additive and multiplicative shear biases significantly, although further
correction via a calibration scheme is required, which also corrects for a
dependence of the bias on galaxy properties. We find that the calibration
relation itself is biased by the use of noisy, measured galaxy properties,
which may limit the final accuracy that can be achieved. We assess the accuracy
of the calibration in the tomographic bins used for the KiDS cosmic shear
analysis, testing in particular the effect of possible variations in the
uncertain distributions of galaxy size, magnitude and ellipticity, and conclude
that the calibration procedure is accurate at the level of multiplicative bias
$\lesssim 1\%$ required for the KiDS cosmic shear analysis.


title:
KiDS-450: Cosmological parameter constraints from tomographic weak
  gravitational lensing

abstract:
  We present cosmological parameter constraints from a tomographic weak
gravitational lensing analysis of ~450deg$^2$ of imaging data from the Kilo
Degree Survey (KiDS). For a flat $\Lambda$CDM cosmology with a prior on $H_0$
that encompasses the most recent direct measurements, we find
$S_8\equiv\sigma_8\sqrt{\Omega_{\rm m}/0.3}=0.745\pm0.039$. This result is in
good agreement with other low redshift probes of large scale structure,
including recent cosmic shear results, along with pre-Planck cosmic microwave
background constraints. A $2.3$-$\sigma$ tension in $S_8$ and `substantial
discordance' in the full parameter space is found with respect to the Planck
2015 results. We use shear measurements for nearly 15 million galaxies,
determined with a new improved `self-calibrating' version of $lens$fit
validated using an extensive suite of image simulations. Four-band $ugri$
photometric redshifts are calibrated directly with deep spectroscopic surveys.
The redshift calibration is confirmed using two independent techniques based on
angular cross-correlations and the properties of the photometric redshift
probability distributions. Our covariance matrix is determined using an
analytical approach, verified numerically with large mock galaxy catalogues. We
account for uncertainties in the modelling of intrinsic galaxy alignments and
the impact of baryon feedback on the shape of the non-linear matter power
spectrum, in addition to the small residual uncertainties in the shear and
redshift calibration. The cosmology analysis was performed blind. Our
high-level data products, including shear correlation functions, covariance
matrices, redshift distributions, and Monte Carlo Markov Chains are available
at http://kids.strw.leidenuniv.nl.


title:
What can Cosmology tell us about Gravity? Constraining Horndeski with
  Sigma and Mu

abstract:
  Phenomenological functions $\Sigma$ and $\mu$ (also known as $G_{\rm
light}/G$ and $G_{\rm matter}/G$) are commonly used to parameterize possible
modifications of the Poisson equation relating the matter density contrast to
the lensing and the Newtonian potentials, respectively. They will be well
constrained by future surveys of large scale structure. But what would the
implications of measuring particular values of these functions be for modified
gravity theories? We ask this question in the context of general Horndeski
class of single field scalar-tensor theories with second order equations of
motion. We find several consistency conditions that make it possible to rule
out broad classes of theories based on measurements of $\Sigma$ and $\mu$ that
are independent of their parametric forms. For instance, a measurement of
$\Sigma \ne 1$ would rule out all models with a canonical form of kinetic
energy, while finding $\Sigma-1$ and $\mu-1$ to be of opposite sign would
strongly disfavour the entire class of Horndeski models. We separately examine
the large and the small scale limits, the possibility of scale-dependence, and
the consistency with bounds on the speed of gravitational waves. We identify
sub-classes of Horndeski theories that can be ruled out based on the measured
difference between $\Sigma$ and $\mu$.


title: Exponential expressivity in deep neural networks through transient chaos

abstract:
  We combine Riemannian geometry with the mean field theory of high dimensional
chaos to study the nature of signal propagation in generic, deep neural
networks with random weights. Our results reveal an order-to-chaos expressivity
phase transition, with networks in the chaotic phase computing nonlinear
functions whose global curvature grows exponentially with depth but not width.
We prove this generic class of deep random functions cannot be efficiently
computed by any shallow network, going beyond prior work restricted to the
analysis of single functions. Moreover, we formalize and quantitatively
demonstrate the long conjectured idea that deep networks can disentangle highly
curved manifolds in input space into flat manifolds in hidden space. Our
theoretical analysis of the expressive power of deep networks broadly applies
to arbitrary nonlinearities, and provides a quantitative underpinning for
previously abstract notions about the geometry of deep functions.


title:
Proceedings Scholar Metrics: H Index of proceedings on Computer Science,
  Electrical & Electronic Engineering, and Communications according to Google
  Scholar Metrics (2010-2014)

abstract:
  The objective of this report is to present a list of proceedings
(conferences, workshops, symposia, meetings) in the areas of Computer Science,
Electrical & Electronic Engineering, and Communications covered by Google
Scholar Metrics and ranked according to their h-index. Google Scholar Metrics
only displays publications that have published at least 100 papers and have
received at least one citation in the last five years (2010-2014). The searches
were conducted between the 8th and 10th of December, 2015. A total of 1501
proceedings have been identified


title:
The black hole merger event GW150914 within a modified theory of General
  Relativity

abstract:
  In February 2016 the first observation of gravitational waves were reported.
The source of this event, denoted as GW150914, was identified as the merger of
two black holes with a about 30 solar masses each, at a distance of
approximately 400Mpc. These data where deduced using the Theory of General
Relativity. Since 2009 a modified theory was proposed which adds near massive
objects phenomenologically the contribution of a dark energy, whose origin are
vacuum uctuations. The dark energy accumulates toward smaller distances,
reducing effec- tively the gravitational constant. In this contribution we show
that as a consequence the deduces chirping mass and the luminosity distance are
larger. This result suggests that the black hole merger corresponds to two
massive black holes near the center of primordial galaxies at large luminosity
distance, i.e. large redshifts.


title:
Magnetic Suppression of Turbulence and the Star Formation Activity of
  Molecular Clouds

abstract:
  We present magnetohydrodynamic simulations aimed at studying the effect of
the magnetic suppression of turbulence (generated through various instabilities
during the formation of molecular clouds by converging) on the subsequent star
formation (SF) activity. We study four magnetically supercritical models with
magnetic field strengths $B= 0$, 1, 2, and 3 $\mu$G (corresponding to
mass--to--flux ratios of $\infty$, 4.76, 2.38, and 1.59 times the critical
value), with the magnetic field, initially being aligned with the flows. We
find that, for increasing magnetic field strength, the clouds formed tend to be
more massive, denser, less turbulent, and with higher SF activity. This causes
the onset of star formation activity in the non--magnetic or more weakly
magnetized cases to be delayed by a few Myr in comparison to the more strongly
magnetized cases. We attribute this behavior to the suppression of the
nonlinear thin shell instability (NTSI) by the magnetic field, previously found
by Heitsch and coworkers. This result is contrary to the standard notion that
the magnetic field provides support to the clouds, thus reducing their star
formation rate (SFR). However, our result is a completely nonlinear one, and
could not be foreseen from simple linear considerations.


title: Can the Baryon Asymmetry Arise From Initial Conditions?

abstract:
  In this letter, we quantify the challenge of explaining the baryon asymmetry
using initial conditions in a universe that undergoes inflation. Contrary to
lore, we find that such an explanation is possible if net $B-L$ number is
stored in a light bosonic field with hyper-Planckian initial displacement and a
delicately chosen field velocity prior to inflation. However, such a
construction may require extremely tuned coupling constants to ensure that this
asymmetry is viably communicated to the Standard Model after reheating; the
large field displacement required to overcome inflationary dilution must not
induce masses for Standard Model particles or generate dangerous washout
processes. While these features are inelegant, this counterexample nonetheless
shows that there is no theorem against such an explanation. We also comment on
potential observables in the double $\beta$-decay spectrum and on model
variations that may allow for more natural realizations.


title:
Spherical collapse, formation hysteresis and the deeply non-linear
  cosmological power spectrum

abstract:
  I examine differences in non-linear structure formation between cosmological
models that share a $z=0$ linear power spectrum in both shape and amplitude,
but that differ via their growth history. $N$-body simulations of these models
display an approximately identical large-scale-structure skeleton, but reveal
deeply non-linear differences in the demographics and properties of haloes. I
investigate to what extent the spherical-collapse model can help in
understanding these differences, in both real and redshift space. I discuss how
this is difficult to do if one attempts to identify haloes directly, because in
that case one is subject to the vagaries of halo finding algorithms. However, I
demonstrate that the halo model of structure formation provides an accurate
non-linear response in the power spectrum, but only if results from spherical
collapse that include formation hysteresis are properly incorporated. I comment
on how this fact can be used to provide per cent level accurate matter power
spectrum predictions for dark energy models for $k\leq5\,h\mathrm{Mpc}^{-1}$ by
using the halo model as a correction to accurate $\Lambda$CDM simulations. In
the appendix I provide some fitting functions for the linear-collapse threshold
($\delta_\mathrm{c}$) and virialized overdensity ($\Delta_\mathrm{v}$) that are
valid for a wide range of dark energy models. I also make my spherical-collapse
code available at https://github.com/alexander-mead/collapse


title:
The SILCC project: III. Regulation of star formation and outflows by
  stellar winds and supernovae

abstract:
  We study the impact of stellar winds and supernovae on the multi-phase
interstellar medium using three-dimensional hydrodynamical simulations carried
out with FLASH. The selected galactic disc region has a size of (500 pc)$^2$ x
$\pm$ 5 kpc and a gas surface density of 10 M$_{\odot}$/pc$^2$. The simulations
include an external stellar potential and gas self-gravity, radiative cooling
and diffuse heating, sink particles representing star clusters, stellar winds
from these clusters which combine the winds from indi- vidual massive stars by
following their evolution tracks, and subsequent supernova explosions. Dust and
gas (self-)shielding is followed to compute the chemical state of the gas with
a chemical network. We find that stellar winds can regulate star (cluster)
formation. Since the winds suppress the accretion of fresh gas soon after the
cluster has formed, they lead to clusters which have lower average masses
(10$^2$ - 10$^{4.3}$ M$_{\odot}$) and form on shorter timescales (10$^{-3}$ -
10 Myr). In particular we find an anti-correlation of cluster mass and
accretion time scale. Without winds the star clusters easily grow to larger
masses for ~5 Myr until the first supernova explodes. Overall the most massive
stars provide the most wind energy input, while objects beginning their
evolution as B-type stars contribute most of the supernova energy input. A
significant outflow from the disk (mass loading $\gtrsim$ 1 at 1 kpc) can be
launched by thermal gas pressure if more than 50% of the volume near the disc
mid-plane can be heated to T > 3x10$^5$ K. Stellar winds alone cannot create a
hot volume-filling phase. The models which are in best agreement with observed
star formation rates drive either no outflows or weak outflows.


title:
Mind your Ps and Qs: the Interrelation between Period (P) and Mass-ratio
  (Q) Distributions of Binary Stars

abstract:
  We compile observations of early-type binaries identified via spectroscopy,
eclipses, long-baseline interferometry, adaptive optics, common proper motion,
etc. Each observational technique is sensitive to companions across a narrow
parameter space of orbital periods P and mass ratios q = M_comp/M_1. After
combining the samples from the various surveys and correcting for their
respective selection effects, we find the properties of companions to O-type
and B-type main-sequence (MS) stars differ among three regimes. First, at short
orbital periods P < 20 days (separations a < 0.4 AU), the binaries have small
eccentricities e < 0.4, favor modest mass ratios <q> = 0.5, and exhibit a small
excess of twins q > 0.95. Second, the companion frequency peaks at intermediate
periods log P (days) = 3.5 (a = 10 AU), where the binaries have mass ratios
weighted toward small values q = 0.2-0.3 and follow a Maxwellian "thermal"
eccentricity distribution. Finally, companions with long orbital periods log P
(days) = 5.5-7.5 (a = 200-5,000 AU) are outer tertiary components in
hierarchical triples, and have a mass ratio distribution across q = 0.1-1.0
that is nearly consistent with random pairings drawn from the initial mass
function. We discuss these companion distributions and properties in the
context of binary star formation and evolution. We also reanalyze the binary
statistics of solar-type MS primaries, taking into account that (30+/-10)% of
single-lined spectroscopic binaries likely contain white dwarf companions
instead of low-mass stellar secondaries. The mean frequency of stellar
companions with q > 0.1 and log P (days) < 8.0 per primary increases from
0.50+/-0.04 for solar-type MS primaries to 2.1+/-0.3 for O-type MS primaries.
We fit joint probability density functions f(M_1,q,P,e) to the corrected
distributions, which can be incorporated into binary population synthesis
studies.


title:
The Prevalence of Gas Outflows in Type 2 AGNs. II. 3D Biconical Outflow
  Models

abstract:
  We present 3D models of biconical outflows combined with a thin dust plane
for investigating the physical properties of the ionized gas outflows and their
effect on the observed gas kinematics in type 2 active galactic nuclei (AGNs).
Using a set of input parameters, we construct a number of models in 3D and
calculate the spatially integrated velocity and velocity dispersion for each
model. We find that three primary parameters, i.e., intrinsic velocity, bicone
inclination, and the amount of dust extinction, mainly determine the simulated
velocity and velocity dispersion. Velocity dispersion increases as the
intrinsic velocity or the bicone inclination increases, while velocity (i.e.,
velocity shifts with respect to systemic velocity) increases as the amount of
dust extinction increases. Simulated emission-line profiles well reproduce the
observed [O III] line profiles, e.g., a narrow core and a broad wing
components. By comparing model grids and Monte Carlo simulations with the
observed [O III] velocity-velocity dispersion (VVD) distribution of ~39,000
type 2 AGNs, we constrain the intrinsic velocity of gas outflows ranging from
~500 km/s to ~1000 km/s for the majority of AGNs, and up to ~1500-2000 km/s for
extreme cases. The Monte Carlo simulations show that the number ratio of AGNs
with negative [O III] velocity to AGNs with positive [O III] velocity
correlates with the outflow opening angle, suggesting that outflows with higher
intrinsic velocity tend to have wider opening angles. These results demonstrate
the potential of our 3D models for studying the physical properties of gas
outflows, applicable to various observations, including spatially integrated
and resolved gas kinematics.


title:
Panchromatic Hubble Andromeda Treasury XVI. Star Cluster Formation
  Efficiency and the Clustered Fraction of Young Stars

abstract:
  We use the Panchromatic Hubble Andromeda Treasury (PHAT) survey dataset to
perform spatially resolved measurements of star cluster formation efficiency
($\Gamma$), the fraction of stellar mass formed in long-lived star clusters. We
use robust star formation history and cluster parameter constraints, obtained
through color-magnitude diagram analysis of resolved stellar populations, to
study Andromeda's cluster and field populations over the last $\sim$300 Myr. We
measure $\Gamma$ of 4-8% for young, 10-100 Myr old populations in M31. We find
that cluster formation efficiency varies systematically across the M31 disk,
consistent with variations in mid-plane pressure. These $\Gamma$ measurements
expand the range of well-studied galactic environments, providing precise
constraints in an HI-dominated, low intensity star formation environment.
Spatially resolved results from M31 are broadly consistent with previous trends
observed on galaxy-integrated scales, where $\Gamma$ increases with increasing
star formation rate surface density ($\Sigma_{\mathrm{SFR}}$). However, we can
explain observed scatter in the relation and attain better agreement between
observations and theoretical models if we account for environmental variations
in gas depletion time ($\tau_{\mathrm{dep}}$) when modeling $\Gamma$,
accounting for the qualitative shift in star formation behavior when
transitioning from a H$_2$-dominated to a HI-dominated interstellar medium. We
also demonstrate that $\Gamma$ measurements in high $\Sigma_{\mathrm{SFR}}$
starburst systems are well-explained by $\tau_{\mathrm{dep}}$-dependent
fiducial $\Gamma$ models.


title:
A spectroscopic follow-up program of very massive galaxies at 3<z<4:
  confirmation of spectroscopic redshifts, and a high fraction of powerful AGN

abstract:
  We present the analysis and results of a spectroscopic follow-up program of a
mass-selected sample of six galaxies at 3 < z < 4 using data from Keck-NIRSPEC
and VLT-Xshooter. We confirm the z > 3 redshifts for half of the sample through
the detection of strong nebular emission lines, and improve the zphot accuracy
for the remainder of the sample through the combination of photometry and
spectra. The modeling of the emission-line-corrected spectral energy
distributions (SEDs) adopting improved redshifts confirms the very large
stellar masses of the sample (M_* ~ 1.5-4 x 10^11 Msun) in the first 2 Gyrs of
cosmic history, with a diverse range in stellar ages, star formation rates and
dust content. From the analysis of emission line luminosities and widths, and
far-infrared (FIR) fluxes we confirm that >80% of the sample are hosts to
luminous hidden active galactic nuclei (AGNs), with bolometric luminosities of
~10^(44-46) erg/s. We find that the MIPS 24um photometry is largely
contaminated by AGN continuum, rendering the SFRs derived using only 24um
photometry to be severely overestimated. By including the emission from the AGN
in the modeling of the UV-to-FIR SEDs, we confirm that the presence of the AGN
does not bias considerably the stellar masses (< 0.3 dex at 1\sigma). We show
evidence for a rapid increase of the AGN fraction from ~30% to ~60-100% over
the 1 Gyr between z~2 and z~3. Although we cannot exclude some enhancement of
the AGN fraction for our sample due to selection effects, the small measured
[OIII] contamination to the observed K-band fluxes suggests that our sample is
not significantly biased toward massive galaxies hosting AGNs.


title: Spatially Resolved Spectroscopy of Sub-mm Galaxies at z~2

abstract:
  We present near-infrared integral-field spectroscopic observations targeting
H$\alpha$ in eight sub-millimeter galaxies (SMGs) at $z$=1.3-2.5 using
VLT/SINFONI, obtaining significant detections for six of them. The star
formation rates derived from the H$\alpha$ emission are $\sim$100
M$_\odot$yr$^{-1}$, which account for only $\sim$ 20-30\% of the
infrared-derived values, thus suggesting that these systems are very dusty. Two
of these systems present [NII]/H$\alpha$ ratios indicative of the presence of
an Active Galactic Nucleus (AGN). We mapped the spatial distribution and
kinematics of the star forming regions in these galaxies on kpc-scales. In
general, the H$\alpha$ morphologies tend to be highly irregular and/or clumpy,
showing spatial extents of $\sim$3-11~kpc. We find evidence for significant
spatial offsets, of $\sim$0.1-0.4$"$ or 1.2-3.4 kpc, between the H$\alpha$ and
the continuum emission in three of the sources. Performing a kinemetry analysis
we conclude that the majority of the sample is not consistent with disk-like
rotation-dominated kinematics. Instead, they tend to show irregular and/or
clumpy and turbulent velocity and velocity dispersion fields. This can be
interpreted as evidence for scenario in which these extreme star formation
episodes are triggered by galaxy-galaxy interactions and major mergers. In
contrast to recent results for SMGs, these sources appear to follow the same
relations between gas and star forming rate densities as less luminous and/or
normal star forming galaxies.


title:
The Little Galaxies that Could (Reionize the Universe): Predicting Faint
  End Slopes & Escape Fractions at z > 4

abstract:
  The sources that reionized the universe are still unknown, but likely
candidates are faint but numerous galaxies. In this paper we present results
from running a high resolution, uniform volume simulation, the Vulcan, to
predict the number densities of undetectable, faint galaxies and their escape
fractions of ionizing radiation, $f_\mathrm{esc}$, during reionization. Our
approach combines a high spatial resolution, a realistic treatment of feedback
and hydro processes, a strict threshold for minimum number of resolution
elements per galaxy, and a converged measurement of $f_\mathrm{esc}$. We
calibrate our physical model using a novel approach to create realistic
galaxies at z=0, so the simulation is predictive at high redshifts. With this
approach we can (1) robustly predict the evolution of the galaxy UV luminosity
function at faint magnitudes down to $M_\mathrm{UV}$~-15, two magnitudes
fainter than observations, and (2) estimate $f_\mathrm{esc}$ over a large range
of galaxy masses based on the detailed stellar and gas distributions in
resolved galaxies. We find steep faint end slopes, implying high number
densities of faint galaxies, and the dependence of $f_\mathrm{esc}$ on the UV
magnitude of a galaxy, given by the power-law: log $f_\mathrm{esc} = (0.51 \pm
0.04)M_\mathrm{UV} + 7.3 \pm 0.8$, with the faint population having
$f_\mathrm{esc}$~35%. Convolving the UV luminosity function with
$f_\mathrm{esc}$($M_\mathrm{UV}$), we find an ionizing emissivity that is (1)
dominated by the faintest galaxies and (2) reionizes the universe at the
appropriate rate, consistent with observational constraints of the ionizing
emissivity and the optical depth to the decoupling surface tau_es, without the
need for additional sources of ionizing radiation.


title: The Neutral Excitations in the Gaffnian State

abstract:
  We study a model fractional quantum Hall (FQH) wavefunction called the
Gaffnian state, which is believed to represent a gapless, strongly correlated
state that is very different from conventional metals. To understand this
exotic gapless state better, we provide a representation based on work of
Halperin in which the pairing structure of the Gaffnian state becomes more
explicit. We employ the single-mode approximation introduced by Girvin,
MacDonald, and Platzman (GMP), here extended to three-body interactions, in
order to treat a neutral collective exitation mode in order to clarify the
physical origin of the gaplessness of the Gaffnian state. We discuss approaches
to extract systematically the relevant physics in the long-distance,
large-electron-number limit of FQH states using numerical calculations with
relatively few electrons. In an appendix, we provide second quantized
expressions for many-body Haldane pseudopotentials in various geometries
including the plane, sphere, cylinder, and the torus based on the proper
definition of the relative angular momentum.


title: EGG: hatching a mock Universe from empirical prescriptions

abstract:
  This paper introduces EGG, the Empirical Galaxy Generator, a tool designed
within the ASTRODEEP collaboration to generate mock galaxy catalogs for deep
fields with realistic fluxes and simple morphologies. The simulation procedure
is based exclusively on empirical prescriptions -- rather than first principles
-- to provide the most accurate match with observations at 0<z<7. In
particular, we consider that galaxies can be either quiescent or star-forming,
and use their stellar mass (M*) and redshift (z) as the fundamental properties
from which all the other observables can be statistically derived. Drawing z
and M* from the observed galaxy stellar mass functions, we associate a star
formation rate (SFR) to each galaxy from the tight SFR-M* main sequence, while
dust attenuation, optical colors and morphologies (including bulge-to-total
ratios, sizes and aspect ratios) are obtained from empirical relations that we
establish from the high quality Hubble and Herschel observations available in
the CANDELS fields. Random scatter is introduced in each step to reproduce the
observed distributions of each parameter. Based on these observables, a
panchromatic spectral energy distribution (SED) is selected for each galaxy and
synthetic photometry is produced by integrating the redshifted SED in common
broad-band filters. Finally, the mock galaxies are placed on the sky at random
positions with a fixed angular two-point correlation function to implement
basic clustering. The resulting flux catalogs reproduce accurately the observed
number counts in all broad bands from the ultraviolet up to the sub-millimeter,
and can be directly fed to image simulators such as Skymaker. The images can
then be used to test source extraction softwares and image-based techniques
such as stacking. EGG is open-source, and is made available to the community
together with a set of pre-generated catalogs and images.


title:
Covariance of Motion and Appearance Featuresfor Spatio Temporal
  Recognition Tasks

abstract:
  In this paper, we introduce an end-to-end framework for video analysis
focused towards practical scenarios built on theoretical foundations from
sparse representation, including a novel descriptor for general purpose video
analysis. In our approach, we compute kinematic features from optical flow and
first and second-order derivatives of intensities to represent motion and
appearance respectively. These features are then used to construct covariance
matrices which capture joint statistics of both low-level motion and appearance
features extracted from a video. Using an over-complete dictionary of the
covariance based descriptors built from labeled training samples, we formulate
low-level event recognition as a sparse linear approximation problem. Within
this, we pose the sparse decomposition of a covariance matrix, which also
conforms to the space of semi-positive definite matrices, as a determinant
maximization problem. Also since covariance matrices lie on non-linear
Riemannian manifolds, we compare our former approach with a sparse linear
approximation alternative that is suitable for equivalent vector spaces of
covariance matrices. This is done by searching for the best projection of the
query data on a dictionary using an Orthogonal Matching pursuit algorithm. We
show the applicability of our video descriptor in two different application
domains - namely low-level event recognition in unconstrained scenarios and
gesture recognition using one shot learning. Our experiments provide promising
insights in large scale video analysis.


title: Spin dynamics of counterrotating Kitaev spirals via duality

abstract:
  Incommensurate spiral order is a common occurrence in frustrated magnetic
insulators. Typically, all magnetic moments rotate uniformly, through the same
wavevector. However the honeycomb iridates family Li2IrO3 shows an
incommensurate order where spirals on neighboring sublattices are
counter-rotating, giving each moment a different local environment.
Theoretically describing its spin dynamics has remained a challenge: the Kitaev
interactions proposed to stabilize this state, which arise from strong
spin-orbit effects, induce magnon umklapp scattering processes in spin-wave
theory. Here we propose an approach via a (Klein) duality transformation into a
conventional spiral of a frustrated Heisenberg model, allowing a direct
derivation of the dynamical structure factor. We analyze both Kitaev and
Dzyaloshinskii-Moriya based models, both of which can stabilize counterrotating
spirals, but with different spin dynamics, and we propose experimental tests to
identify the origin of counterrotation.


title: Chirality and Circular Polarization in Models of Inflation

abstract:
  We investigate the possibility that a chiral asymmetry during inflation can
manifest as net circular polarization in photons. Using an example known to
produce a helicity imbalance in fermions, we show that superhorizon photon
modes produced during inflation acquire net circular polarization. Modes that
reenter the horizon around last scattering can thermalize into the Cosmic
Microwave Background while retaining a portion of their net circular
polarization. We also consider the possibility of direct detection of the
circular polarization in the CMB.


title:
Participant number fluctuations for higher moments of a multiplicity
  distribution

abstract:
  The independent participant model is generalized for skewness and kurtosis.
The obtained relations allow to calculate the fluctuations of an arbitrarily
high order. From the comparison with the SPS and the LHC data it is found that
the participants are not nucleons. The contribution of the participant
fluctuations increases with the order of fluctuations. The 5% centrality bins
selected for the analysis at the LHC by ALICE seems to be too large. The
fluctuations measures are dominated by the fluctuations of participants there.
The method to quantify the value of participant number fluctuations
experimentally is proposed.


title: Towards resolving strongly-interacting dark sectors at colliders

abstract:
  Dark sectors with strong interactions have received considerable interest.
Assuming the existence of a minimally coupled dark sector which runs to strong
interactions in the infrared, we address the question whether the scaling
behavior of this dark sector can be observed in missing energy signatures at
present and future hadron colliders. We compare these findings to the concrete
case of self-interacting dark matter and demonstrate that the energy dependence
of high-momentum transfer final states can in principle be used to gain
information about the UV structure of hidden sectors at future hadron
colliders, subject to large improvements in systematic uncertainties, which
could complement proof-of-principle lattice investigations. We also comment on
the case of dark Abelian $U(1)$ theories.


title:
Transformation, normalization and batch effect in the analysis of mass
  spectrometry data for omics studies

abstract:
  Data transformation, normalization and handling of batch effect are a key
part of data analysis for almost all spectrometry-based omics data. This paper
reviews and contrasts these three distinct aspects. We present a systematic
overview of the key approaches and critically review some common procedures.
Much of this paper is inspired by mass spectrometry based experimentation, but
most of our discussion carries over to omics data using distinct spectrometric
approaches generally.


title: Impact of storage competition on energy markets

abstract:
  We study how storage, operating as a price maker within a market environment,
may be optimally operated over an extended period of time. The optimality
criterion may be the maximisation of the profit of the storage itself, where
this profit results from the exploitation of the differences in market clearing
prices at different times. Alternatively it may be the minimisation of the cost
of generation, or the maximisation of consumer surplus or social welfare. In
all cases there is calculated for each successive time-step the cost function
measuring the total impact of whatever action is taken by the storage. The
succession of such cost functions provides the information for the storage to
determine how to behave over time, forming the basis of the appropriate
optimisation problem. Further, optimal decision making, even over a very long
or indefinite time period, usually depends on a knowledge of costs over a
relatively short running time horizon -- for storage of electrical energy
typically of the order of a day or so.
  We study particularly competition between multiple stores, where the
objective of each store is to maximise its own income given the activities of
the remainder. We show that, at the Cournot Nash equilibrium, multiple large
stores collectively erode their own abilities to make profits: essentially each
store attempts to increase its own profit over time by overcompeting at the
expense of the remainder. We quantify this for linear price functions
  We give examples throughout based on Great Britain spot-price market data.


title: Activity-assisted self-assembly of colloidal particles

abstract:
  We outline a basic strategy of how self-propulsion can be used to improve the
yield of a typical colloidal self-assembly process. The success of this
approach is predicated on the thoughtful design of the colloidal building block
as well as how self-propulsion is endowed to the particle. As long as a set of
criteria are satisfied, it is possible to significantly increase the rate of
self-assembly, and greatly expand the window in parameter space where
self-assembly can occur. In addition, we show that by tuning the relative
on/off time of the self-propelling force it is possible to modulate the
effective speed of the colloids allowing for further optimization of the
self-assembly process.


title: Predicting Ambulance Demand: Challenges and Methods

abstract:
  Predicting ambulance demand accurately at a fine resolution in time and space
(e.g., every hour and 1 km$^2$) is critical for staff / fleet management and
dynamic deployment. There are several challenges: though the dataset is
typically large-scale, demand per time period and locality is almost always
zero. The demand arises from complex urban geography and exhibits complex
spatio-temporal patterns, both of which need to captured and exploited. To
address these challenges, we propose three methods based on Gaussian mixture
models, kernel density estimation, and kernel warping. These methods provide
spatio-temporal predictions for Toronto and Melbourne that are significantly
more accurate than the current industry practice.


title:
First measurement of nuclear recoil head-tail sense in a fiducialised
  WIMP dark matter detector

abstract:
  Recent computational results suggest that directional dark matter detectors
have potential to probe for WIMP dark matter particles below the neutrino
floor. The DRIFT-IId detector used in this work is a leading directional WIMP
search time projection chamber detector. We report the first measurements of
the detection of the directional nuclear recoils in a fully fiducialised
low-pressure time projection chamber. In this new operational mode, the
distance between each event vertex and the readout plane is determined by the
measurement of minority carriers produced by adding a small amount of oxygen to
the nominal CS$_{2}$ + CF$_{4}$ target gas mixture. The CS$_2$ + CF$_4$ + O$_2$
mixture has been shown to enable background-free operation at current
sensitivities. Sulfur, fluorine, and carbon recoils were generated using
neutrons emitted from a $^{252}$Cf source positioned at different locations
around the detector. Measurement of the relative energy loss along the recoil
tracks allowed the track vector sense, or the so-called head-tail asymmetry
parameter, to be deduced. Results show that the previously reported observation
of head-tail sensitivity in pure CS$_{2}$ is well retained after the addition
of oxygen to the gas mixture.


title:
Improved sampling and validation of frozen Gaussian approximation with
  surface hopping algorithm for nonadiabatic dynamics

abstract:
  In the spirit of the fewest switches surface hopping, the frozen Gaussian
approximation with surface hopping (FGA-SH) method samples a path integral
representation of the non-adiabatic dynamics in the semiclassical regime. An
improved sampling scheme is developed in this work for FGA-SH based on birth
and death branching processes. The algorithm is validated for the standard test
examples of non-adiabatic dynamics.


title:
On exact solution of topological CFT models based on Kazama-Suzuki
  cosets

abstract:
  We compute the flat coordinates on the Frobenius manifolds arising on the
deformation space of Gepner $\hat{SU}(3)_k$ chiral rings. The explicit form of
the flat coordinates is important for exact solutions of models of topological
CFT and 2d Liouville gravity. We describe the case k=3, which is of particular
interest because apart from the relevant chiral fields it contains a marginal
one. Whereas marginal perturbations are relevant in different contexts, their
analysis requires additional care compared to the relevant perturbations.


title: Counting Automorphic Forms on Norm One Tori

abstract:
  We give an asymptotic formula for the number of automorphic forms on the
non-split norm one torus $T$ associated with an imaginary quadratic extension
of $\mathbb{Q}$, ordered by analytic conductor.


title: Quantum atomistic approach for interacting spins

abstract:
  The phenomenological Landau theory of the spin precession has been used to
reproduce the out-of-equilibrium properties of many magnetic systems. However,
such an approach suffers from some serious limitations. The main reason is that
the spin and the angular momentum of the atoms are described by the classical
theory of the angular momentum. We derive a discrete model that extends the
Landau theory to the quantum mechanical framework. Our approach is based on the
application of the quantification procedure to the classical hamiltonian of an
array of interacting spins. The connection with the classical dynamics is
discussed.


title: Fisher information from stochastic quantum measurements

abstract:
  The unavoidable interaction between a quantum system and the external noisy
environment can be mimicked by a sequence of stochastic measurements whose
outcomes are neglected. Here we investigate how this stochasticity is reflected
in the survival probability to find the system in a given Hilbert subspace at
the end of the dynamical evolution. In particular, we analytically study the
distinguishability of two different stochastic measurement sequences in terms
of a new Fisher information measure depending on the variation of a function,
instead of a finite set of parameters. We find a novel characterization of Zeno
phenomena as the physical result of the random observation of the quantum
system, linked to the sensitivity of the survival probability with respect to
an arbitrary small perturbation of the measurement stochasticity. Finally, the
implications on the Cram\'er-Rao bound are discussed, together with a numerical
example. These results are expected to provide promising applications in
quantum metrology towards future, more robust, noise-based quantum sensing
devices.


title: Template-Assisted Direct Growth of 1Td/in$^2$ Bit Patterned Media

abstract:
  We present a method for growing bit patterned magnetic recording media using
directed growth of sputtered granular perpendicular magnetic recording media.
The grain nucleation is templated using an epitaxial seed layer which contains
Pt pillars separated by amorphous metal oxide. The scheme enables the creation
of both templated data and servo regions suitable for high density hard disk
drive operation. We illustrate the importance of using a process that is both
topographically and chemically driven to achieve high quality media.


title:
Babcock Redux: An Ammendment of Babcock's Schematic of the Sun's
  Magnetic Cycle

abstract:
  We amend Babcock's original scenario for the global dynamo process that
sustains the Sun's 22-year magnetic cycle. The amended scenario fits
post-Babcock observed features of the magnetic activity cycle and convection
zone, and is based on ideas of Spruit and Roberts (1983) about magnetic flux
tubes in the convection zone. A sequence of four schematic cartoons lays out
the proposed evolution of the global configuration of the magnetic field above,
in, and at the bottom of the convection zone through sunspot Cycle 23 and into
Cycle 24. Three key elements of the amended scenario are: (1) as the net
following-polarity field from the sunspot-region omega-loop fields of an
ongoing sunspot cycle is swept poleward to cancel and replace the
opposite-polarity polar-cap field from the previous sunspot cycle, it remains
connected to the ongoing sunspot cycle's toroidal source-field band at the
bottom of the convection zone; (2) topological pumping by the convection zone's
free convection keeps the horizontal extent of the poleward-migrating
following-polarity field pushed to the bottom, forcing it to gradually cancel
and replace old horizontal field below it that connects the ongoing-cycle
source-field band to the previous-cycle polar-cap field; (3) in each polar
hemisphere, by continually shearing the poloidal component of the settling new
horizontal field, the latitudinal differential rotation low in the convection
zone generates the next-cycle source-field band poleward of the ongoing-cycle
band. The amended scenario is a more-plausible version of Babcock's scenario,
and its viability can be explored by appropriate kinematic flux-transport
solar-dynamo simulations.


title: Hyperbolic waveguide for long-distance transport of near-field heat flux

abstract:
  Heat flux exchanged between two hot bodies at subwavelength separation
distances can exceed the limit predicted by the blackbody theory. However this
super-Planckian transfer is restricted to these separation distances. Here we
demonstrate the possible existence of a super-Planckian transfer at arbitrary
large separation distances if the interacting bodies are connected in
near-field with weakly dissipating hyperbolic waveguides. This result opens the
way to long distance transport of near-field thermal energy.


title: Folding and Stabilization of Native-Sequence-Reversed Proteins

abstract:
  Though the problem of sequence-reversed protein folding is largely
unexplored, one might speculate that reversed native protein sequences should
be significantly more foldable than purely random heteropolymer sequences. In
this article, we investigate how the reverse-sequences of native proteins might
fold by examining a series of small proteins of increasing structural
complexity ({\alpha}-helix, \b{eta}-hairpin, {\alpha}-helix bundle, and
{\alpha}/\b{eta}-protein). Employing a tandem protein structure prediction
algorithmic and molecular dynamics simulation approach, we find that the
ability of reverse sequences to adopt native-like folds is strongly in
influenced by protein size and the flexibility of the native hydrophobic core.
For \b{eta}-hairpins with reverse-sequences that fail to fold, we employ a
simple mutational strategy for guiding stable hairpin formation that involves
the insertion of amino acids into the \b{eta}-turn region. This systematic look
at reverse sequence duality sheds new light on the problem of protein
sequence-structure mapping and may serve to inspire new protein design and
protein structure prediction protocols.

categories: q-bio.BM cond-mat.soft physics.bio-ph physics.chem-ph


title:
Avoiding Imposters and Delinquents: Adversarial Crowdsourcing and Peer
  Prediction

abstract:
  We consider a crowdsourcing model in which $n$ workers are asked to rate the
quality of $n$ items previously generated by other workers. An unknown set of
$\alpha n$ workers generate reliable ratings, while the remaining workers may
behave arbitrarily and possibly adversarially. The manager of the experiment
can also manually evaluate the quality of a small number of items, and wishes
to curate together almost all of the high-quality items with at most an
$\epsilon$ fraction of low-quality items. Perhaps surprisingly, we show that
this is possible with an amount of work required of the manager, and each
worker, that does not scale with $n$: the dataset can be curated with
$\tilde{O}\Big(\frac{1}{\beta\alpha^3\epsilon^4}\Big)$ ratings per worker, and
$\tilde{O}\Big(\frac{1}{\beta\epsilon^2}\Big)$ ratings by the manager, where
$\beta$ is the fraction of high-quality items. Our results extend to the more
general setting of peer prediction, including peer grading in online
classrooms.


title:
Crossover between fast and slow excitation of magnetization by spin
  torque

abstract:
  A crossover between two mechanisms destabilizing the magnetization in
equilibrium by the spin transfer effect is found in a ferromagnetic multilayer
consisting of an in-plane magnetized free layer and a perpendicularly
magnetized pinned layer, where an in-plane magnetic field is applied, and
electric current flows from the pinned to the free layer. A fast transition
from the in-plane to the out-of-plane state occurs in the low-field region,
whereas a slow transition with small-amplitude oscillation becomes dominant in
the high-field region. On the other hand, only the fast transition mechanism
appears for the opposite current direction.


title:
The fully packed loop model as a non-rational $W_3$ conformal field
  theory

abstract:
  The fully packed loop (FPL) model is a statistical model related to the
integrable $U_q(\hat{\mathfrak{sl}}_3)$ vertex model. In this paper we study
the continuum limit of the FPL. With the appropriate weight of non-contractible
loops, we give evidence of an extended $W_3$ symmetry in the continuum. The
partition function on the torus is calculated exactly, yielding new modular
invariants of $W_3$ characters. The full CFT spectrum is obtained, and is found
to be in excellent agreement with exact diagonalisation.


title: HELP: star formation as function of galaxy environmentwith Herschel

abstract:
  The Herschel Extragalactic Legacy Project (HELP) brings together a vast range
of data from many astronomical observatories. Its main focus is on the Herschel
data, which maps dust obscured star formation over 1300 deg$^2$. With this
unprecedented combination of data sets, it is possible to investigate how the
star formation vs stellar mass relation (main-sequence) of star-forming
galaxies depends on environment. In this pilot study we explore this question
between 0.1 < z < 3.2 using data in the COSMOS field. We estimate the local
environment from a smoothed galaxy density field using the full photometric
redshift probability distribution. We estimate star formation rates by stacking
the SPIRE data from the Herschel Multi-tiered Extragalactic Survey (HerMES).
Our analysis rules out the hypothesis that the main-sequence for star-forming
systems is independent of environment at 1.5 < z < 2, while a simple model in
which the mean specific star formation rate declines with increasing
environmental density gives a better description. However, we cannot exclude a
simple hypothesis in which the main-sequence for star-forming systems is
independent of environment at z < 1.5 and z > 2. We also estimate the evolution
of the star formation rate density in the COSMOS field and our results are
consistent with previous measurements at z < 1.5 and z > 2 but we find a
$1.4^{+0.3}_{-0.2}$ times higher peak value of the star formation rate density
at $z \sim 1.9$.


title: Simpler Context-Dependent Logical Forms via Model Projections

abstract:
  We consider the task of learning a context-dependent mapping from utterances
to denotations. With only denotations at training time, we must search over a
combinatorially large space of logical forms, which is even larger with
context-dependent utterances. To cope with this challenge, we perform
successive projections of the full model onto simpler models that operate over
equivalence classes of logical forms. Though less expressive, we find that
these simpler models are much faster and can be surprisingly effective.
Moreover, they can be used to bootstrap the full model. Finally, we collected
three new context-dependent semantic parsing datasets, and develop a new
left-to-right parser.


title: Is a monotone union of contractible open sets contractible?

abstract:
  This paper presents some partial answers to the following question.
  QUESTION. If a normal space X is the union of an increasing sequence of open
sets U(1), U(2), U(3) ... such that each U(n) contracts to a point in X, must X
be contractible?
  The main results of the paper are:
  THEOREM 1. If a normal space X is the union of a sequence of open subsets {
U(n) } such that the closure of U(n) is contained in U(n+1) and U(n) contracts
to a point in U(n+1) for each n > 0, then X is contractible.
  COROLLARY 2. If a locally compact sigma-compact normal space X is the union
of an increasing sequence of open sets U(1), U(2), U(3) ... such that each U(n)
contracts to a point in X, then X is contractible.


title: New families of strongly regular graphs

abstract:
  In this article we construct a series of new infinite families of strongly
regular graphs with the same parameters as the point-graphs of non-singular
quadrics in PG(n,2).


title: Deep Image Set Hashing

abstract:
  In applications involving matching of image sets, the information from
multiple images must be effectively exploited to represent each set.
State-of-the-art methods use probabilistic distribution or subspace to model a
set and use specific distance measure to compare two sets. These methods are
slow to compute and not compact to use in a large scale scenario.
Learning-based hashing is often used in large scale image retrieval as they
provide a compact representation of each sample and the Hamming distance can be
used to efficiently compare two samples. However, most hashing methods encode
each image separately and discard knowledge that multiple images in the same
set represent the same object or person. We investigate the set hashing problem
by combining both set representation and hashing in a single deep neural
network. An image set is first passed to a CNN module to extract image
features, then these features are aggregated using two types of set feature to
capture both set specific and database-wide distribution information. The
computed set feature is then fed into a multilayer perceptron to learn a
compact binary embedding. Triplet loss is used to train the network by forming
set similarity relations using class labels. We extensively evaluate our
approach on datasets used for image matching and show highly competitive
performance compared to state-of-the-art methods.


title: Sampling Method for Fast Training of Support Vector Data Description

abstract:
  Support Vector Data Description (SVDD) is a popular outlier detection
technique which constructs a flexible description of the input data. SVDD
computation time is high for large training datasets which limits its use in
big-data process-monitoring applications. We propose a new iterative
sampling-based method for SVDD training. The method incrementally learns the
training data description at each iteration by computing SVDD on an independent
random sample selected with replacement from the training data set. The
experimental results indicate that the proposed method is extremely fast and
provides a good data description .


title:
Numerical Simulations of Early-Stage Dynamics of Electron Bunches
  Emitted from Plasmonic Photocathodes

abstract:
  High-brightness electron sources are a key ingredient to the development of
compact accelerator-based light sources. The electron sources are commonly
based on (linear) photoemission process where a laser pulse with proper
wavelength impinges on the surface of a metallic or semiconductor photocathode.
Very recently, the use of plasmonic cathodes - cathodes with a nano-patterned
surface - have demonstrated great enhancement in quantum efficiencies (Li et
al., 2013 [1]). Alternatively, this type of photocathodes could support the
formation of structured beams composed of transversely-separated beamlets. In
this paper we discuss numerical simulations of the early-stage beam dynamics of
the emission process from plasmonic cathodes carried out using the Warp
(Friedman et al., 2014 [2]) framework. The model is used to investigate the
properties of beams emitted from these photocathode and subsequently combined
with particle-in-cell simulations to explore the imaging of cathode pattern
after acceleration in a radiofrequency gun.


title: On the Maximum-Weight Basis Problem

abstract:
  Let M to be a matroid defined on a finite set E. A subset L of E is locked in
M if L is 2-connected in M, the complement of L is 2-connected in the dual M*,
and min{r(L), r*(complement of L)} is greater than 1. In this paper, we prove
that the nontrivial facets of the bases polytope of M are described by the
locked subsets. We deduce that finding the maximum-weight basis of M is a
polynomial problem for matroids with a polynomial number of locked subsets.
This class of matroids is closed under 2-sums and contains uniform matroids.


title:
D2O - a distributed data object for parallel high-performance computing
  in Python

abstract:
  We introduce D2O, a Python module for cluster-distributed multi-dimensional
numerical arrays. It acts as a layer of abstraction between the algorithm code
and the data-distribution logic. The main goal is to achieve usability without
losing numerical performance and scalability. D2O's global interface is similar
to the one of a numpy.ndarray, whereas the cluster node's local data is
directly accessible for use in customized high-performance modules. D2O is
written in pure Python which makes it portable and easy to use and modify.
Expensive operations are carried out by dedicated external libraries like numpy
and mpi4py. The performance of D2O is on a par with numpy for serial
applications and scales well when moving to an MPI cluster. D2O is open-source
software available under the GNU General Public License v3 (GPL-3) at
https://gitlab.mpcdf.mpg.de/ift/D2O


title: Model-Agnostic Interpretability of Machine Learning

abstract:
  Understanding why machine learning models behave the way they do empowers
both system designers and end-users in many ways: in model selection, feature
engineering, in order to trust and act upon the predictions, and in more
intuitive user interfaces. Thus, interpretability has become a vital concern in
machine learning, and work in the area of interpretable models has found
renewed interest. In some applications, such models are as accurate as
non-interpretable ones, and thus are preferred for their transparency. Even
when they are not accurate, they may still be preferred when interpretability
is of paramount importance. However, restricting machine learning to
interpretable models is often a severe limitation. In this paper we argue for
explaining machine learning predictions using model-agnostic approaches. By
treating the machine learning models as black-box functions, these approaches
provide crucial flexibility in the choice of models, explanations, and
representations, improving debugging, comparison, and interfaces for a variety
of users and models. We also outline the main challenges for such methods, and
review a recently-introduced model-agnostic explanation approach (LIME) that
addresses these challenges.


title:
Image Edge Detection based on Swarm Intelligence using Memristive
  Networks

abstract:
  Recent advancements in the development of memristive devices has opened new
opportunities for hardware implementation of non-Boolean computing. To this
end, the suitability of memristive devices for swarm intelligence algorithms
has enabled researchers to solve a maze in hardware. In this paper, we utilize
swarm intelligence of memristive networks to perform image edge detection.
First, we propose a hardware-friendly algorithm for image edge detection based
on ant colony. Second, we implement the image edge detection algorithm using
memristive networks. Furthermore, we explain the impact of various parameters
of the memristors on the efficacy of the implementation. Our results show 28%
improvement in the energy compared to a low power CMOS hardware implementation
based on stochastic circuits. Furthermore, our design occupies up to 5x less
area.


title: Analysis of the Lepton Mixing Matrix in the Two Higgs Doublet Model

abstract:
  In the theoretical framework of Two Higgs Doublet Model (2HDM) plus three
right-handed neutrinos we consider a universal treatment for the mass matrices,
aside from that the active neutrinos acquire their small mass through the
type-I seesaw mechanism. Then, as long as a matrix with four-zero texture is
used to represent the right-handed neutrinos and Yukawa matrices, we obtain a
unified treatment where all fermion mass matrices have four-zero texture. We
obtain analytical and explicit expressions for the lepton flavour mixing matrix
PMNS in terms of fermion masses and parameters associated with the 2HDM-III.
Further, we compare these expressions of the PMNS matrix with the most up to
date values of masses and mixing in the lepton sector, via a likelihood test
$\chi^{2}$. We find that the analytical expressions that we derived reproduce
remarkably well the most recent experimental data of neutrino oscillations.


title:
Nothing works the first time: An expert experimental physics
  epistemology

abstract:
  The ability to troubleshoot is an important learning outcome for
undergraduate physics laboratory courses. To better understand the role of
troubleshooting in electronics laboratory courses, we interviewed 20
electronics instructors from multiple institution types about their beliefs and
teaching practices related to troubleshooting. In these interviews, instructors
articulated the idea that \emph{nothing works the first time} in multiple
contexts pertaining to troubleshooting. We argue that this idea is an expert
epistemology and show how it informs instructors' beliefs that (i) students
need to know how to troubleshoot, (ii) students should expect to troubleshoot,
(iii) all circuit-building lab activities provide opportunities for students to
troubleshoot, and (iv) students' ability to construct functional circuits can
be a proxy for their ability to troubleshoot malfunctioning circuits. Moreover,
we discuss implications for instruction and assessment of troubleshooting in
electronics courses.


title: Making Tree Ensembles Interpretable

abstract:
  Tree ensembles, such as random forest and boosted trees, are renowned for
their high prediction performance, whereas their interpretability is critically
limited. In this paper, we propose a post processing method that improves the
model interpretability of tree ensembles. After learning a complex tree
ensembles in a standard way, we approximate it by a simpler model that is
interpretable for human. To obtain the simpler model, we derive the EM
algorithm minimizing the KL divergence from the complex ensemble. A synthetic
experiment showed that a complicated tree ensemble was approximated reasonably
as interpretable.


title:
Technique Report: Scheduling Flows with Multiple Service Frequency
  Constraints

abstract:
  With the fast development of wireless technologies, wireless applications
have invaded various areas in people's lives with a wide range of capabilities.
Guaranteeing Quality-of-Service (QoS) is the key to the success of those
applications. One of the QoS requirements, service frequency, is very important
for tasks including multimedia transmission in the Internet of Things. A
service frequency constraint denotes the length of time period during which a
link can transmit at least once. Unfortunately, it has not been well addressed
yet. Therefore, this paper proposes a new framework to schedule multi
transmitting flows in wireless networks considering service frequency
constraint for each link. In our model, the constraints for flows are
heterogeneous due to the diversity of users' behaviors. We first introduce a
new definition for network stability with service frequency constraints and
demonstrate that the novel scheduling policy is throughput-optimal in one
fundamental category of network models. After that, we discuss the performance
of a wireless network with service frequency constraints from the views of
capacity region and total queue length. Finally, a series of evaluations
indicate the proposed scheduling policy can guarantee service frequency and
achieve a good performance on the aspect of queue length of each flow.


title: Strictly nonclassical behavior of a mesoscopic system

abstract:
  We experimentally demonstrate the strictly nonclassical behavior in a
many-atom system using a recently derived criterion [E. Kot et al., Phys. Rev.
Lett. 108, 233601 (2012)] that explicitly does not make use of quantum
mechanics. We thereby show that the magnetic moment distribution measured by
McConnell et al. [R. McConnell et al., Nature 519, 439 (2015)] in a system with
a total mass of $2.6\times 10^5$ atomic mass units is inconsistent with
classical physics. Notably, the strictly nonclassical behavior affects an area
in phase space $10^3$ times larger than the Planck quantum $\hbar$.


title: Atomically-thin Ohmic Edge Contacts Between Two-dimensional Materials

abstract:
  With the decrease of the dimensions of electronic devices, the role played by
electrical contacts is ever increasing, eventually coming to dominate the
overall device volume and total resistance. This is especially problematic for
monolayers of semiconducting transition metal dichalcogenides (TMDs), which are
promising candidates for atomically thin electronics. Ideal electrical contacts
to them would require the use of similarly thin electrode materials while
maintaining low contact resistances. Here we report a scalable method to
fabricate ohmic graphene edge contacts to two representative monolayer TMDs -
MoS2 and WS2. The graphene and TMD layer are laterally connected with
wafer-scale homogeneity, no observable overlap or gap, and a low average
contact resistance of 30 k$\Omega$ $\mu$m. The resulting graphene edge contacts
show linear current-voltage (IV) characteristics at room temperature, with
ohmic behavior maintained down to liquid helium temperatures.


title:
The tight subgiant branch of the intermediate-age star cluster NGC 411
  implies a single-aged stellar population

abstract:
  The presence of extended main-sequence turn-off (eMSTO) regions in
intermediate-age star clusters in the Large and Small Magellanic Clouds is
often interpreted as resulting from extended star-formation histories (SFHs),
lasting $\geq$ 300 Myr. This strongly conflicts with the traditional view of
the dominant star-formation mode in stellar clusters, which are thought of as
single-aged stellar populations. Here we present a test of this interpretation
by exploring the morphology of the subgiant branch (SGB) of NGC 411, which
hosts possibly the most extended eMSTO among all known intermediate-age star
clusters. We show that the width of the NGC 411 SGB favours the single-aged
stellar population interpretation and rules out an extended SFH. In addition,
when considering the red clump (RC) morphology and adopting the unproven
premise that the widths of all features in the colour--magnitude diagram are
determined by an underlying range in ages, we find that the SFH implied is
still very close to that resulting from a single-aged stellar population, with
a minor fraction of stars scattering to younger ages compared with the bulk of
the population. The SFHs derived from the SGB and RC are both inconsistent with
the SFH derived from the eMSTO region. NGC 411 has a very low escape velocity
and it has unlikely undergone significant mass loss at an early stage, thus
indicating that it may lack the capacity to capture most of its initial,
expelled gas from stellar evolutionary processes, a condition often required
for extended SFHs to take root.


title:
Global regularity of three dimensional density patch for inhomogeneous
  incompressible viscous flow

abstract:
  The present work is devoted to proving that the boundary regularity of the
three dimensional density patch persists by time evolution for inhomogeneous
incompressible viscous flow, with some smallness condition on the initial
velocity.


title: Feedback-Aided Coded Caching for the MISO BC with Small Caches

abstract:
  This work explores coded caching in the symmetric $K$-user cache-aided MISO
BC with imperfect CSIT-type feedback, for the specific case where the cache
size is much smaller than the library size. Building on the recently explored
synergy between caching and delayed-CSIT, and building on the tradeoff between
caching and CSIT quality, the work proposes new schemes that boost the impact
of small caches, focusing on the case where the cumulative cache size is
smaller than the library size. For this small-cache setting, based on the
proposed near-optimal schemes, the work identifies the optimal cache-aided
degrees-of-freedom (DoF) performance within a factor of 4.


title: The unbroken spectrum of type-A Frobenius seaweeds

abstract:
  If $\mathfrak{g}$ is a Frobenius Lie algebra, then for certain $F\in
\mathfrak{g}^*$ the natural map $\mathfrak{g}\longrightarrow \mathfrak{g}^* $
given by $x \longmapsto F[x,-]$ is an isomorphism. The inverse image of $F$
under this isomorphism is called a principal element. We show that if
$\mathfrak{g}$ is a Frobenius seaweed subalgebra of $A_{n-1}=\mathfrak{sl}(n)$
then the spectrum of the adjoint of a principal element consists of an unbroken
set of integers whose multiplicities have a symmetric distribution. Our proof
methods are constructive and combinatorial in nature.


title: A product rule for triangular numbers

abstract:
  We prove that there are exactly five sequences, including the triangular
numbers, that satisfy the product rule $T(mn) = T(m) T(n) + T(m-1) T(n-1)$ for
all $m, n \ge 1$.


title:
Broadband Circular Polarizers Constructed by Helix-like Chiral
  Metamaterials

abstract:
  In this paper, a kind of helix-like chiral metamaterial, which can be
realized with multiple conventional lithography or electron beam lithographic
techniques, is proposed to achieve broadband bianisotropic optical response
analogous to helical metamaterial. On the basis of twisted metamaterial, via
tailoring the relative orientation within the lattice, the anisotropy of arc is
converted into magneto-electric coupling of closely spaced arc pairs, which
leads to a broad bianisotropic optical response. By connecting the adjacent
upper and lower arcs, the coupling of metasurface pairs is transformed to the
coupling of the three-dimensional inclusions, and provides a much broader and
higher bianisotropic optical response. For only a four-layer helix-like
metamaterial, the maximum extinction ratio can reach 19.7. The operation band
is in the wavelength range from 4.69 {\mu}m to 8.98 {\mu}m with an average
extinction ratio of 6.9. And the transmittance for selective polarization is
above 0.8 in the entire operation band. Such a structure is promising for
integratable and scalable broadband circular polarizers, especially has great
potential to act as broadband circular micropolarizers in the field of the
full-stokes division of focal plane polarimeters.


title: Complex systems: features, similarity and connectivity

abstract:
  The increasing interest in complex networks research has been a consequence
of several intrinsic features of this area, such as the generality of the
approach to represent and model virtually any discrete system, and the
incorporation of concepts and methods deriving from many areas, from
statistical physics to sociology, which are often used in an independent way.
Yet, for this same reason, it would be desirable to integrate these various
aspects into a more coherent and organic framework, which would imply in
several benefits normally allowed by the systematization in science, including
the identification of new types of problems and the cross-fertilization between
fields. More specifically, the identification of the main areas to which the
concepts frequently used in complex networks can be applied paves the way to
adopting and applying a larger set of concepts and methods deriving from those
respective areas. Among the several areas that have been used in complex
networks research, pattern recognition, optimization, linear algebra, and time
series analysis seem to play a more basic and recurrent role. In the present
manuscript, we propose a systematic way to integrate the concepts from these
diverse areas regarding complex networks research. In order to do so, we start
by grouping the multidisciplinary concepts into three main groups, namely
features, similarity, and network connectivity. Then we show that several of
the analysis and modeling approaches to complex networks can be thought as a
composition of maps between these three groups, with emphasis on nine main
types of mappings, which are presented and illustrated. Such a systematization
of principles and approaches also provides an opportunity to review some of the
most closely related works in the literature, which is also developed in this
article.