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VL-BERT: Pre-training of Generic Visual-Linguistic RepresentationsAug 22 2019We introduce a new pre-trainable generic representation for visual-linguistic tasks, called Visual-Linguistic BERT (VL-BERT for short). VL-BERT adopts the simple yet powerful Transformer model as the backbone, and extends it to take both visual and linguistic ... More

Sequential Latent Spaces for Modeling the Intention During Diverse Image CaptioningAug 22 2019Diverse and accurate vision+language modeling is an important goal to retain creative freedom and maintain user engagement. However, adequately capturing the intricacies of diversity in language models is challenging. Recent works commonly resort to latent ... More

Unsupervised Lemmatization as Embeddings-Based Word ClusteringAug 22 2019We focus on the task of unsupervised lemmatization, i.e. grouping together inflected forms of one word under one label (a lemma) without the use of annotated training data. We propose to perform agglomerative clustering of word forms with a novel distance ... More

ViCo: Word Embeddings from Visual Co-occurrencesAug 22 2019We propose to learn word embeddings from visual co-occurrences. Two words co-occur visually if both words apply to the same image or image region. Specifically, we extract four types of visual co-occurrences between object and attribute words from large-scale, ... More

Double Reinforcement Learning for Efficient Off-Policy Evaluation in Markov Decision ProcessesAug 22 2019Off-policy evaluation (OPE) in reinforcement learning allows one to evaluate novel decision policies without needing to conduct exploration, which is often costly or otherwise infeasible. We consider for the first time the semiparametric efficiency limits ... More

Intersection times for critical branching random walkAug 22 2019We show that for a sequence of reversible Markov chains, the mixing-times are of smaller order than the maximal hitting times $t_{\mathrm{hit}}^{(n)}$ iff the product of the spectral-gap $\mathrm{gap}^{(n)}$ and $t_{\mathrm{hit}}^{(n)}$ diverges. This ... More

Dynamical resolution scale in transverse momentum distributions at the LHCAug 22 2019The QCD evolution of transverse momentum dependent (TMD) distribution functions has recently been formulated in a parton branching (PB) formalism. In this approach, soft-gluon coherence effects are taken into account by introducing the soft-gluon resolution ... More

Compositional Video PredictionAug 22 2019We present an approach for pixel-level future prediction given an input image of a scene. We observe that a scene is comprised of distinct entities that undergo motion and present an approach that operationalizes this insight. We implicitly predict future ... More

On the dichotomy of a locally compact semitopological monoid of order isomorphisms between principal filters of $\mathbb{N}^n$ with adjoined zeroAug 22 2019Let $n$ be any positive integer and $\mathscr{I\!P\!F}(\mathbb{N}^n)$ be the semigroup of all order isomorphisms between principal filters of the $n$-th power of the set of positive integers $\mathbb{N}$ with the product order. We prove that a Hausdorff ... More

Adversarial-Based Knowledge Distillation for Multi-Model Ensemble and Noisy Data RefinementAug 22 2019Generic Image recognition is a fundamental and fairly important visual problem in computer vision. One of the major challenges of this task lies in the fact that single image usually has multiple objects inside while the labels are still one-hot, another ... More

Unfolding as Quantum AnnealingAug 22 2019High-energy physics is replete with hard computational problems and it is one of the areas where quantum computing could be used to speed up calculations. We present an implementation of likelihood-based regularized unfolding on a quantum computer. The ... More

Aspects of AdS$_2$ classification in M-theory: Solutions with mesonic and baryonic chargesAug 22 2019We construct necessary and sufficient geometric conditions for AdS$_2$ solutions of M-theory with, at least, minimal supersymmetry to exist. We generalize previous results in the literature for ${\cal N}=(2,0)$ supersymmetry in AdS$_2$ to ${\cal N}=(1,0)$. ... More

Six-dimensional gauge theories and (twisted) generalized cohomologyAug 22 2019We consider the global aspects of the 6-dimensional $\mathcal{N}=(1, 0)$ theory arising from the coupling of the vector multiplet to the tensor multiplet. We show that the Yang-Mills field and its dual, when both are abelianized, combine to define a class ... More

Experimental Demonstration of Exceptional Points of Degeneracy in Linear Time Periodic Systems and Exceptional SensitivityAug 22 2019We present the first experimental demonstration of the occurrence of exceptional points of degeneracy (EPDs) in a single resonator system by introducing a linear time-periodic variation to one of its components, in contrast to parity time (PT)-symmetric ... More

Entropy-cooled nonequilibrium states of the Hubbard modelAug 22 2019We show that the recently proposed cooling-by-doping mechanism allows to efficiently prepare interesting nonequilibrium states of the Hubbard model. Using nonequilibrium dynamical mean field theory and a particle-hole symmetric setup with dipolar excitations ... More

Reflections on Virasoro circuit complexity and Berry phaseAug 22 2019Recently, the notion of circuit complexity defined in symmetry group manifolds has been related to geometric actions which generally arise in the coadjoint orbit method in representation theory and play an important role in geometric quantization. On ... More

A Decomposition and Metric-Based Evaluation Framework for MicroservicesAug 22 2019Migrating from monolithic systems into microservice is a very complex task. Companies are commonly decomposing the monolithic system manually, analyzing dependencies of the monolith and then assessing different decomposition options. The goal of our work ... More

Dynamics of Bubbling Wave Maps with Prescribed RadiationAug 22 2019We study energy critical one-equivariant wave maps taking values in the two-sphere. It is known that any finite energy wave map that develops a singularity does so by concentrating the energy of (possibly) several copies of the ground state harmonic map ... More

Spatially resolved spectroscopy of the debris disk HD 32297: Further evidence of small dust grainsAug 22 2019Spectro-photometry of debris disks in total intensity and polarimetry can provide new insight into the properties of the dust grains therein (size distribution and optical properties). We aim to constrain the morphology of the highly inclined debris disk ... More

Speeding-up Ab Initio Molecular Dynamics with Hybrid Functionals using Adaptively Compressed Exchange Operator based Multiple TimesteppingAug 22 2019Ab initio molecular dynamics (AIMD) simulations using hybrid density functionals and plane waves are of great interest owing to the accuracy of this approach in treating condensed matter systems. On the other hand, such AIMD calculations are not routinely ... More

Navigation of a Quadratic Potential with Ellipsoidal ObstaclesAug 22 2019Given a convex quadratic potential of which its minimum is the agent's goal and a space populated with ellipsoidal obstacles, one can construct a Rimon-Koditschek artificial potential to navigate. These potentials are such that they combine the natural ... More

Scaling of wetting and pre-wetting transitions on nano-patterned wallsAug 22 2019We consider a nano-patterned planar wall consisting of a periodic array of stripes of width $L$, which are completely wet by liquid (contact angle $\theta=0$), separated by regions of width $D$ which are completely dry (contact angle $\theta=\pi)$. Using ... More

Transfer Learning for Relation Extraction via Relation-Gated Adversarial LearningAug 22 2019Relation extraction aims to extract relational facts from sentences. Previous models mainly rely on manually labeled datasets, seed instances or human-crafted patterns, and distant supervision. However, the human annotation is expensive, while human-crafted ... More

Predicting Animation Skeletons for 3D Articulated Models via Volumetric NetsAug 22 2019We present a learning method for predicting animation skeletons for input 3D models of articulated characters. In contrast to previous approaches that fit pre-defined skeleton templates or predict fixed sets of joints, our method produces an animation ... More

ColorNet -- Estimating Colorfulness in Natural ImagesAug 22 2019Measuring the colorfulness of a natural or virtual scene is critical for many applications in image processing field ranging from capturing to display. In this paper, we propose the first deep learning-based colorfulness estimation metric. For this purpose, ... More

In-phase and anti-phase synchronization in a laser frequency combAug 22 2019Coupled clocks are a classic example of a synchronization system leading to periodic collective oscillations. This phenomenon already attracted the attention of Christian Huygens back in 1665,who described it as a kind of "sympathy" among oscillators. ... More

A Pieri rule for Demazure characters of the general linear groupAug 22 2019The Pieri rule is a nonnegative, multiplicity-free formula for the Schur function expansion of the product of an arbitrary Schur function with a single row Schur function. Key polynomials are characters of Demazure modules for the general linear group ... More

IMPRESSION -- Prediction of NMR Parameters for 3-dimensional chemical structures using Machine Learning with near quantum chemical accuracyAug 22 2019The IMPRESSION (Intelligent Machine PREdiction of Shift and Scalar Information Of Nuclei) machine learning system provides an efficient and accurate route to the prediction of NMR parameters from 3-dimensional chemical structures. Here we demonstrate ... More

Search for supersymmetry using Higgs boson to diphoton decays at $\sqrt{s}$ = 13 TeVAug 22 2019A search for supersymmetry (SUSY) is presented where at least one Higgs boson is produced and decays to two photons in the decay chains of pair-produced SUSY particles. Two complementary analysis strategies are pursued: one focused on strong SUSY production ... More

General Composite Non-Abelian Strings and Flag Manifold Sigma ModelsAug 22 2019We fully investigate the symmetry breaking patterns occurring upon creation of composite non-Abelian strings: vortex strings in non-Abelian theories where different sets of colours have different amounts of flux. After spontaneous symmetry breaking, there ... More

EPIC-Fusion: Audio-Visual Temporal Binding for Egocentric Action RecognitionAug 22 2019We focus on multi-modal fusion for egocentric action recognition, and propose a novel architecture for multi-modal temporal-binding, i.e. the combination of modalities within a range of temporal offsets. We train the architecture with three modalities ... More

DynGraph2Seq: Dynamic-Graph-to-Sequence Interpretable Learning for Health Stage Prediction in Online Health ForumsAug 22 2019Online health communities such as the online breast cancer forum enable patients (i.e., users) to interact and help each other within various subforums, which are subsections of the main forum devoted to specific health topics. The changing nature of ... More

Cavity electromechanics with parametric mechanical drivingAug 22 2019Microwave optomechanical circuits have been demonstrated in the past years to be extremely powerfool tools for both, exploring fundamental physics of macroscopic mechanical oscillators as well as being promising candidates for novel on-chip quantum limited ... More

Applying machine learning optimization methods to the production of a quantum gasAug 22 2019We apply three machine learning strategies to optimize the atomic cooling processes utilized in the production of a Bose-Einstein condensate (BEC). For the first time, we optimize both laser cooling and evaporative cooling mechanisms simultaneously. We ... More

The double traveling salesman problem with partial last-in-first-out loading constraintsAug 22 2019In this paper, we introduce the Double Traveling Salesman Problem with Partial Last-In-First-Out Loading Constraints (DTSPPL), a pickup-and-delivery single-vehicle routing problem where all pickup operations must be performed before any delivery one because ... More

A Hybrid Method for Online Trajectory Planning of Mobile Robots in Cluttered EnvironmentsAug 22 2019This paper presents a method for online trajectory planning in known environments. The proposed algorithm is a fusion of sampling-based techniques and model-based optimization via quadratic programming. The former is used to efficiently generate an obstacle-free ... More

Some remarks on the asymptotic profile of solutions to structurally damped $σ$-evolution equationsAug 22 2019In this paper, we are interested in analyzing the asymptotic profiles of solutions to the Cauchy problem for linear structurally damped $\sigma$-evolution equations in $L^2$-sense. Depending on the parameters $\sigma$ and $\delta$ we would like to not ... More

On determinantal curves and complexified phase-lock areas in a model of Josephson junctionAug 22 2019The paper deals with a three-parameter family of special double confluent Heun equations that was introduced and studied by V.M.Buchstaber and S.I.Tertychnyi as an equivalent presentation of a model of overdamped Josephson junction in superconductivity. ... More

Constraining the Sea Quark Distributions Through W$^\pm$ Cross Section Ratio Measurements at STARAug 22 2019Over the past several years, parton distribution functions (PDFs) have become more precise. However there are still kinematic regions where more data are needed to help constrain global PDF extractions, such as the ratio of the sea quark distributions ... More

Time series model selection with a meta-learning approach; evidence from a pool of forecasting algorithmsAug 22 2019One of the challenging questions in time series forecasting is how to find the best algorithm. In recent years, a recommender system scheme has been developed for time series analysis using a meta-learning approach. This system selects the best forecasting ... More

On the dependent product in toposesAug 22 2019We give an explicit construction of the dependent product in an elementary topos, and a site-theoretic description for it in the case of a Grothendieck topos.

Lower bounds and fixed points for the centered Hardy--Littlewood maximal operatorAug 22 2019For all $p>1$ and all centrally symmetric convex bodies $K\subset \mathbb{R}^d$ define $Mf$ as the centered maximal function associated to $K$. We show that when $d=1$ or $d=2$, we have $||Mf||_p\ge (1+\epsilon(p,K))||f||_p$. For $d\ge 3$, let $q_0(K)$ ... More

A Neural Model for Dialogue Coherence AssessmentAug 22 2019Dialogue quality assessment is crucial for evaluating dialogue agents. An essential factor of high-quality dialogues is coherence - what makes dialogue utterances a whole. This paper proposes a novel dialogue coherence model trained in a hierarchical ... More

Simulation Model of Two-Robot Cooperation in Common Operating EnvironmentAug 22 2019The article considers a simulation modelling problem related to the chess game process occurring between two three-tier manipulators. The objective of the game construction lies in developing the procedure of effective control of the autonomous manipulator ... More

Improved bounds for the sunflower lemmaAug 22 2019A sunflower with $r$ petals is a collection of $r$ sets so that the intersection of each pair is equal to the intersection of all. Erd\H{o}s and Rado proved the sunflower lemma: for any fixed $r$, any family of sets of size $w$, with at least about $w^w$ ... More

A mathematical model describing the localization and spread of influenza A virus infection within the human respiratory tractAug 22 2019Within the human respiratory tract (HRT), viruses diffuse through the periciliary fluid (PCF) bathing the epithelium, and travel upwards via advection towards the nose and mouth, as the mucus escalator entrains the PCF. While many mathematical models ... More

Rayleigh Random Flights on the Poisson line SIRSNAug 22 2019This paper reports a study of scale-invariant Rayleigh Random Flights ("RRF'') in random environments given by planar Scale-Invariant Random Spatial Networks ("SIRS") based on speed-marked Poisson line processes. RRF can be viewed as producing "randomly ... More

On the Close Correspondence between Storm-time ULF Wave Power and the POES VLF Chorus Wave Amplitude ProxyAug 22 2019Ground-based Pc5 ULF wave power in multiple ground-based meridians is compared to the VLF wave amplitude proxy, derived from POES precipitation, for the 33 storms studied by Li et al. [2015]. The results reveal common L-shell and time profiles for the ... More

Iterative Hard Thresholding for Low CP-rank Tensor ModelsAug 22 2019Recovery of low-rank matrices from a small number of linear measurements is now well-known to be possible under various model assumptions on the measurements. Such results demonstrate robustness and are backed with provable theoretical guarantees. However, ... More

Two Decades of Network Science as seen through the co-authorship network of network scientistsAug 22 2019Complex networks have attracted a great deal of research interest in the last two decades since Watts & Strogatz, Barab\'asi & Albert and Girvan & Newman published their highly-cited seminal papers on small-world networks, on scale-free networks and on ... More

Quantum Spin Liquid in a depleted triangular lattice Iridate K$_x$Ir$_y$O$_2$Aug 22 2019We report discovery of a new iridate family K$_x$Ir$_y$O$_2$ with depleted triangular lattice planes made up of edge sharing IrO$_6$ octahedra separated by K planes. Such a material interpolates between the triangular and honeycomb lattices and is a new ... More

The many Shapley values for model explanationAug 22 2019The Shapley value has become a popular method to attribute the prediction of a machine-learning model on an input to its base features. The Shapley value [1] is known to be the unique method that satisfies certain desirable properties, and this motivates ... More

Measuring $H_0$ in PTA with gravitational wavesAug 22 2019Pulsar Timing Arrays have yet to find convincing evidence of gravitational waves. Some time ago it was pointed out by one of the authors that a dramatic enhancement of the signal would take place for particular values of the angle subtended by the source ... More

Bounding Game Temperature Using Confusion IntervalsAug 22 2019For combinatorial games, temperature is a measure of the volatility, that is, by how much the advantage can change. Typically, the temperature has been measured for individual positions within specific games. In this paper, we give the first general upper ... More

Nests and Chains of Hofstadter ButterfliesAug 22 2019The \lq Hofstadter butterfly', a plot of the spectrum of an electron in a two-dimensional periodic potential with a uniform magnetic field, contains subsets which resemble small, distorted images of the entire plot. We show how the sizes of these sub-images ... More

Data Context Adaptation for Accurate Recommendation with Additional InformationAug 22 2019Given a sparse rating matrix and an auxiliary matrix of users or items, how can we accurately predict missing ratings considering different data contexts of entities? Many previous studies proved that utilizing the additional information with rating data ... More

Discovery of tidally-perturbed pulsations in the eclipsing binary U Gru: a pioneering system for tidal asteroseismologyAug 22 2019The interior physics of stars is currently not well constrained for early-type stars. This is particularly pertinent for multiple systems as binary interaction becomes more prevalent for more massive stars, which strongly affects their evolution. High-precision ... More

Phase diagram and quantum criticality of Heisenberg spin chains with Ising-like interchain couplings -- Implication to YbAlO$_3$Aug 22 2019Motivated by recent progress on field-induced phase transitions in quasi-one-dimensional quantum antiferromagnets, we study the phase diagram of $S=1/2$ antiferromagnetic Heisenberg chains with Ising anisotropic interchain couplings under a longitudinal ... More

On the convergence of single-call stochastic extra-gradient methodsAug 22 2019Variational inequalities have recently attracted considerable interest in machine learning as a flexible paradigm for models that go beyond ordinary loss function minimization (such as generative adversarial networks and related deep learning systems). ... More

Revisiting the R* theory: preemption enables multispecies coexistence on a single resourceAug 22 2019Resource competition theory (R* theory) predicts that the species with the highest efficiency (lowest resource requirements) will exclude all other species when competing over a single resource. This prediction contrasts the vast diversity in natural ... More

From quantized spins to rotating black holesAug 22 2019It has been shown recently that classical-spin limit of minimally coupled spinning particles can reproduce the dynamics of Kerr black holes. This raises the intriguing question of how particles with finite (quantized) spins can capture the classical potential ... More

The amplitude of the kilohertz quasi-periodic oscillations in 4U 1636$-$53 in the frequency-energy spaceAug 22 2019We present for the neutron-star low-mass X-ray binary 4U 1636$-$53, and for the first time for any source of kilohertz quasi-periodic oscillations (kHz QPOs), the two-dimensional behaviour of the fractional rms amplitude of the kHz QPOs in the parameter ... More

Search for flavour-changing neutral currents in processes with one top quark and a photon using 81 fb$^{-1}$ of $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS experimentAug 22 2019A search for flavour-changing neutral current (FCNC) events via the coupling of a top quark, a photon, and an up or charm quark is presented using 81 fb$^{-1}$ of proton-proton collision data taken at a centre-of-mass energy of 13 TeV with the ATLAS detector ... More

Phase-dependent Spin Polarization of Cooper Pairs in Magnetic Josephson JunctionsAug 22 2019Superconductor-Ferromagnet hybrid structures (SF) have attracted much interest in the last decades, due to a variety of interesting phenomena predicted and observed in these structures. One of them is the so-called inverse proximity effect. It is described ... More

Comment on the paper by D. Efremov and Yu.N. Ovchinnikov "Singular ground state of multiband inhomogeneous superconductors", Phys. Rev. B 99, 224508 (2019)Aug 22 2019We show that the conclusion reported in Ref. 1, that there are no spontaneous magnetic fields in multiband superconductors that break time reversal symmetry, is incorrect. We demonstrate that the state proposed in Ref. 1 is not a solution of the Ginzburg-Landau ... More

Searches for steady neutrino emission from 3FHLblazars using eight years of IceCube data from theNorthern hemisphereAug 22 2019Located at the South Pole, the IceCube Neutrino Observatory is the world largest neutrino telescope, instrumenting one cubic kilometre of Antarctic ice at a depth between 1450m to 2450m. In 2013 IceCube reported the first observations of a diffuse astrophysical ... More

Electromagnetic wave scattering from local perturbed periodic inhomogeneous layersAug 22 2019We consider the scattering problem on locally perturbed periodic penetrable dielectric layers, which is formulated in terms of the full vector-valued time-harmonic Maxwell's equations. The right-hand side is not assumed to be periodic. At first, we derive ... More

Validating time-distance helioseismic inversions for non-separable subsurface profiles of an average supergranuleAug 22 2019Supergranules are divergent 30-Mm sized cellular flows observed everywhere at the solar photosphere. Their place in the hierarchy of convective structures and their origin remain poorly understood (Rincon et al., 2018). Estimating supergranular depth ... More

Nucleon-antinucleon annihilation at LEARAug 22 2019This report is a historical review of the salient results in low energy antiproton-proton and antineutron-proton annihilation obtained at the Low Energy Antiproton Ring (LEAR), which was operated at CERN between 1983 and 1996. The intention is to provide ... More

Tractable Reformulations of Distributionally Robust Two-stage Stochastic Programs with $\infty-$Wasserstein DistanceAug 22 2019In the optimization under uncertainty, decision-makers first select a wait-and-see policy before any realization of uncertainty and then place a here-and-now decision after the uncertainty has been observed. Two-stage stochastic programming is a popular ... More

Noise Flow: Noise Modeling with Conditional Normalizing FlowsAug 22 2019Modeling and synthesizing image noise is an important aspect in many computer vision applications. The long-standing additive white Gaussian and heteroscedastic (signal-dependent) noise models widely used in the literature provide only a coarse approximation ... More

A new measure of modularity density for community detectionAug 22 2019Using an intuitive concept of what constitutes a meaningful community, a novel metric is formulated for detecting non-overlapping communities in undirected, weighted heterogeneous networks. This metric, modularity density, is shown to be superior to the ... More

Causal Fermion Systems: An Elementary Introduction to Physical Ideas and Mathematical ConceptsAug 22 2019We give an elementary introduction to the theory of causal fermion systems, with a focus on the underlying physical ideas and the conceptual and mathematical foundations.

Efficient Cross-Validation of Echo State NetworksAug 22 2019Echo State Networks (ESNs) are known for their fast and precise one-shot learning of time series. But they often need good hyper-parameter tuning for best performance. For this good validation is key, but usually, a single validation split is used. In ... More

On the recent parametric determination of an asteroseismological model for the DBV star KIC 08626021Aug 22 2019Asteroseismology of white dwarf (WD) stars is a powerful tool that allows to reveal the hidden chemical structure of WD and infer details about their evolution by comparing the observed periods with those obtained from stellar models. A recent asteroseismological ... More

Affine equivalence for quadratic rotation symmetric Boolean functionsAug 22 2019Let $f_n(x_0, x_1, \ldots, x_{n-1})$ denote the algebraic normal form (polynomial form) of a rotation symmetric (RS) Boolean function of degree $d$ in $n \geq d$ variables and let $wt(f_n)$ denote the Hamming weight of this function. Let $(0, a_1, \ldots, ... More

New Nonexistence Results on Circulant Weighing MatricesAug 22 2019A circulant weighing matrix $W = (w_{i,j}) \in CW(n,k)$ is a square matrix of order $n$ and entries $w_{i,j}$ in $\{-1, 0, +1\}$ such that $WW^T=kI_n$. In his thesis, Strassler gave tables of known results on such matrices with $n \leq 200$ and $k \leq ... More

Characterization of Two PMT Models for the IceCube Upgrade mDOMAug 22 2019The IceCube Upgrade will expand the IceCube Neutrino Observatory with nearly 800 new optical modules. A large fraction of these will be multi-PMT optical modules (mDOMs), featuring 24 PMTs pointing uniformly in all directions, providing an almost homogeneous ... More

A Gauge Fixing Procedure for Causal Fermion SystemsAug 22 2019Causal fermion systems incorporate local gauge symmetry in the sense that the Lagrangian and all inherent structures are invariant under local phase transformations of the physical wave functions. In the present paper it is explained and worked out in ... More

Hierarchical Bayes Modeling for Large-Scale InferenceAug 22 2019Bayesian modeling is now ubiquitous in problems of large-scale inference even when frequentist criteria are in mind for evaluating the performance of a procedure. By far most popular in literature of the past decade and a half are empirical Bayes methods, ... More

All-microwave holonomic control of an electron-nuclear two-qubit register in diamondAug 22 2019We present a theoretical scheme that allows to perform a universal set of holonomic gates on a two qubit register, formed by a $^{13}$C nuclear spin coupled to the electron spin of a nitrogen-vacancy center in diamond. Strong hyperfine interaction between ... More

Quantitative portfolio selection: using density forecasting to find consistent portfoliosAug 22 2019In the knowledge that the ex-post performance of Markowitz efficient portfolios is inferior to that implied ex-ante, we make two contributions to the portfolio selection literature. Firstly, we propose a methodology to identify the region of risk-expected ... More

Optimal unions of scaled copies of domains and Pólya's conjectureAug 22 2019Given a bounded Euclidean domain $\Omega$, we consider the sequence of optimisers of the $k^{\rm th}$ Laplacian eigenvalue within the family consisting of all possible disjoint unions of scaled copies of $\Omega$ with fixed total volume. We show that ... More

Topological phases in two-legged Heisenberg ladders with alternated interactionsAug 22 2019We analyze the possible existence of topological phases in two-legged spin ladders considering a staggered interaction in both chains. When the staggered interaction in one chain is shifted by one site with respect to the other chain, the model can be ... More

On the cohomology of line bundles over certain flag schemesAug 22 2019Let $G$ be the group scheme $\operatorname{SL}_{d+1}$ over $\mathbb{Z}$ and let $Q$ be the parabolic subgroup scheme corresponding to the simple roots $\alpha_{2},\cdots,\alpha_{d-1}$. Then $G/Q$ is the $\mathbb{Z} $-scheme of partial flags $\{D_{1}\subset ... More

Scanning a focus through scattering media without using the optical memory effectAug 22 2019Wavefront shaping makes it possible to form a focus through opaque scattering materials. In some cases, this focus may be scanned over a small distance using the optical memory effect. However, in many cases of interest, the optical memory effect has ... More

Thermally activated magnetization reversal in a FeCoB nanomagnet. High-precision measurement method of coercive field, delta, retention time and size of nucleation domainAug 22 2019Features of thermally-activated magnetization switching have been studied in a FeCoB nanomagnet using the N\'eel model. A method of a high-precision measurement of the coercive field, retention time, parameter delta and the size of the switching nucleation ... More

Discrete spectrum for amenable group actionsAug 22 2019In this paper, we study discrete spectrum of invariant measures for countable discrete amenable group actions. We show that an invariant measure has discrete spectrum if and only if it has bounded measure complexity. We also prove that, discrete spectrum ... More

On the cohomology of line bundles over certain flag schemes IIAug 22 2019Over a field $K$ of characteristic $p$, let $Z$ be the incidence variety in $\mathbb{P}^d \times (\mathbb{P}^d)^*$ and let $\mathcal{L}$ be the restriction to $Z$ of the line bundle $\mathcal{O}(-n-d) \boxtimes \mathcal{O}(n)$, where $n = p+f$ with $0 ... More

Residues of skew rational functions and linearized Goppa codesAug 22 2019This paper constitutes a first attempt to do analysis with skew polynomials. Precisely, our main objective is to develop a theory of residues for skew rational functions (which are, by definition, the quotients of two skew polynomials). We prove in particular ... More

On the Structural Properties of Social Networks and their Measurement-calibrated Synthetic CounterpartsAug 22 2019Data-driven analysis of large social networks has attracted a great deal of research interest. In this paper, we investigate 120 real social networks and their measurement-calibrated synthetic counterparts generated by four well-known network models. ... More

Recovery of the Derivative of the Conductivity at the BoundaryAug 22 2019We describe a method to reconstruct the conductivity and its normal derivative at the boundary from the knowledge of the potential and current measured at the boundary. This boundary determination implies the uniqueness of the conductivity in the bulk ... More

Superstring Amplitudes, Unitarity, and Hankel Determinants of Multiple Zeta ValuesAug 22 2019The interplay of unitarity and analyticity has long been known to impose strong constraints on scattering amplitudes in quantum field theory and string theory. This has been highlighted in recent times in a number of papers and lecture notes. Here we ... More

Lower bounds for the centered Hardy-Littlewood maximal operator on the real lineAug 22 2019Let $1<p<\infty$. We prove that there exists an $\varepsilon_p>0$ such that for each $f\in L^p(\mathbb{R})$, the centered Hardy-Littlewood maximal operator $M$ on $\mathbb{R}$ satisfies the lower bound $\|Mf\|_{L^p(\mathbb{R})}\ge (1+\varepsilon_p)\|f\|_{L^p(\mathbb{R})}$. ... More

An introduction to p-adic period ringsAug 22 2019This paper is the augmented notes of a course I gave jointly with Laurent Berger in Rennes in 2014. Its aim was to introduce the periods rings B crys and B dR and state several comparison theorems between{\'e}tale and crystalline or de Rham cohomologies ... More

What Determines the Sizes of Bars in Spiral Galaxies?Aug 22 2019I use volume- and mass-limited subsamples and recently published data from the Spitzer Survey of Stellar Structure in Galaxies (S4G) to investigate how the size of bars depends on galaxy properties. The known correlation between bar semi-major-axis $a$ ... More

Spectral rigidity of random Schrödinger operators via Feynman-Kac formulasAug 22 2019We develop a technique for proving number rigidity (in the sense of Ghosh-Peres) of the spectrum of general random Schr\"odinger operators (RSOs). Our method makes use of Feynman-Kac formulas to estimate the variance of exponential linear statistics of ... More

Multi-messenger tests of cosmic-ray acceleration in radiatively inefficient accretion flowsAug 22 2019The cores of active galactic nuclei (AGNs) have been suggested as the sources of IceCube neutrinos, and recent numerical simulations have indicated that hot AGN coronae of Seyfert galaxies and radiatively inefficient accretion flows (RIAFs) of low-luminosity ... More

When is the Sum of Two Closed Subgroups Closed in a Locally Compact Abelian GroupAug 22 2019Locally compact abelian groups are classified in which the sum of any two closed subgroups is itself closed. This amounts to reproving and extending results by Yu.~N.~Mukhin from 1970. Namely we contribute a complete classification of all totally disconnected ... More

Active Learning for Chinese Word Segmentation in Medical TextAug 22 2019Electronic health records (EHRs) stored in hospital information systems completely reflect the patients' diagnosis and treatment processes, which are essential to clinical data mining. Chinese word segmentation (CWS) is a fundamental and important task ... More