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June 2019 arXiv papers — page 17

Showing 1,6011,700 of 12,804 papers

  1. Sabyasachi Barik, Aziz Karasahin, Sunil Mittal, Edo Waks

    Topological photonic structures exhibit chiral edge states that are robust to disorder and sharp bends. When coupled to quantum emitters, these edge states generate directional light emission that enables unprecedented control of interactions between light and matter in a nanophotonic device. While directional light emission in one-dimensional topological, a

  2. Reyhaneh Khasseh, Rosario Fazio, Stefano Ruffo, Angelo Russomanno

    We study synchronisation between periodically driven, interacting classical spins undergoing a Hamiltonian dynamics. In the thermodynamic limit there is a transition between a regime where all the spins oscillate synchronously for an infinite time with a period twice as the driving period (synchronized regime) and a regime where the oscillations die after a

  3. Xiangcheng Ma, Michael Y. Grudić, Eliot Quataert, Philip F. Hopkins

    We report the formation of bound star clusters in a sample of high-resolution cosmological zoom-in simulations of z>5 galaxies from the FIRE project. We find that bound clusters preferentially form in high-pressure clouds with gas surface densities over 10^4 Msun pc^-2, where the cloud-scale star formation efficiency is near unity and young stars born in the

  4. Pieter van Dokkum, Colleen Gilhuly, Ana Bonaca, Allison Merritt

    In 2008 it was reported that the stellar stream of the edge-on spiral NGC5907 loops twice around the galaxy, enveloping it in a giant corkscrew-like structure. Here we present imaging of this iconic object with the Dragonfly Telephoto Array, reaching a $1\sigma$ surface brightness level of $\mu_g\approx 30.5$ mag/arcsec$^2$ on spatial scales of 1' (the appro

  5. V. Akshay, H. Philathong, M. E. S. Morales, J. Biamonte

    The quantum approximate optimization algorithm (QAOA) has rapidly become a cornerstone of contemporary quantum algorithm development. Despite a growing range of applications, only a few results have been developed towards understanding the algorithms ultimate limitations. Here we report that QAOA exhibits a strong dependence on a problem instances constraint

  6. Christian W. Bauer, Pier Francesco Monni

    In the framework of soft-collinear effective theory (SCET), we show how to formulate the resummation for a broad family of final-state, global observables in high-energy collisions in a general way that is suitable for a numerical calculation. Contrary to the standard SCET approach, this results in a method that does not require an observable-specific factor

  7. Felicity C. Eperon, Bogdan Ganchev, Jorge E. Santos

    We present a plausible counterexample to the weak cosmic censorship conjecture in the four-dimensional Einstein-Scalar theory with asymptotically flat boundary conditions. Our setup stems from the analysis of the massive Klein-Gordon equation on a fixed Kerr black hole background. In particular, we construct the quasinormal spectrum numerically, and analytic

  8. Paul C. Duffell

    This study uses numerical hydrodynamics calculations and a novel method for densely sampling parameter space to measure the precise shape of a gap opened by a planet in a gaseous disk, as a function of planet-to-star mass ratio, disk Mach number, and disk viscosity. Formulas for gap depth and width are determined, which are combined to form a complete formul

  9. Eleonora Di Valentino, Ricardo Z. Ferreira, Luca Visinelli, Ulf Danielsson

    We consider a quintessence field which transitions from a matter-like to a cosmological constant behavior between recombination and the present time. We aim at easing the tension in the measurement of the present Hubble rate, and we assess the $\Lambda$CDM model properly enlarged to include our quintessence field against cosmological observations. The model

  10. Ron Donagi, Mark Macerato, Eric Sharpe

    The Bagger-Witten line bundle is a line bundle over moduli spaces of two-dimensional SCFTs, related to the Hodge line bundle of holomorphic top-forms on Calabi-Yau manifolds. It has recently been a subject of a number of conjectures, but concrete examples have proven elusive. In this paper we collect several results on this structure, including a proposal fo

  11. William Berdanier, Jamir Marino, Ehud Altman

    We show that the dynamics of a quantum impurity subject to a stochastic drive on one side and coupled to a quantum critical system on the other display a universal behavior inherited from the quantum critical scaling. Using boundary conformal field theory, we formulate a generic ansatz for the dynamical scaling form of the typical Loschmidt echo and corrobor

  12. Tim Cunningham, Pier-Emmanuel Tremblay, Bernd Freytag, Hans-Günther Ludwig

    We present a theoretical description of macroscopic diffusion caused by convective overshoot in pure-hydrogen DA white dwarfs using three-dimensional (3D), closed-bottom, radiation hydrodynamics CO$^5$BOLD simulations. We rely on a new grid of deep 3D white dwarf models in the temperature range 11400 K $\leq T_{\mathrm{eff}} \leq$ 18000 K where tracer partic

  13. Monica Guica, Ruben Monten

    We use the variational principle approach to derive the large $N$ holographic dictionary for two-dimensional $T\bar T$-deformed CFTs, for both signs of the deformation parameter. The resulting dual gravitational theory has mixed boundary conditions for the non-dynamical graviton; the boundary conditions for matter fields are undeformed. When the matter field

  14. Snir Gazit, Fakher F. Assaad, Subir Sachdev

    We present a sign-problem free quantum Monte Carlo study of a model that exhibits quantum phase transitions without symmetry breaking and associated changes in the size of the Fermi surface. The model is an Ising gauge theory on the square lattice coupled to an Ising matter field and spinful `orthogonal' fermions at half-filling, both carrying Ising gauge ch

  15. Pietro Benetti Genolini, Juan Manuel Pérez Ipiña, James Sparks

    We derive a simple formula for the action of any supersymmetric solution to minimal gauged supergravity in the AdS$_4$/CFT$_3$ correspondence. Such solutions are equipped with a supersymmetric Killing vector, and we show that the holographically renormalized action may be expressed entirely in terms of the weights of this vector field at its fixed points, to

  16. Ryan Hausen, Brant Robertson

    We present Morpheus, a new model for generating pixel-level morphological classifications of astronomical sources. Morpheus leverages advances in deep learning to perform source detection, source segmentation, and morphological classification pixel-by-pixel via a semantic segmentation algorithm adopted from the field of computer vision. By utilizing morpholo

  17. Naor Alaluf, Moran Feldman

    In this paper we consider the problem of maximizing a non-negative submodular function subject to a cardinality constraint in the data stream model. Previously, the best known algorithm for this problem was a $5.828$-approximation semi-streaming algorithm based on a local search technique (Feldman et al., 2018). For the special case of this problem in which

  18. Dominic J. D. Hughes

    Proofs are traditionally syntactic, inductively generated objects. This paper reformulates first-order logic (predicate calculus) with proofs which are graph-theoretic rather than syntactic. It defines a combinatorial proof of a formula $\phi$ as a lax fibration over a graph associated with $\phi$. The main theorem is soundness and completeness: a formula is

  19. Fanny Yang, Zuowen Wang, Christina Heinze-Deml

    This work provides theoretical and empirical evidence that invariance-inducing regularizers can increase predictive accuracy for worst-case spatial transformations (spatial robustness). Evaluated on these adversarially transformed examples, we demonstrate that adding regularization on top of standard or adversarial training reduces the relative error by 20%

  20. Min Hoon Kim, JungHwan Park

    We present infinitely many homology spheres which contain two distinct knots whose 0-surgeries are $S^1 \times S^2$. This resolves a question posed by Kirby and Melvin in 1978.

  21. Nahuel Freitas, Jean-Charles Delvenne, Massimiliano Esposito

    We develop a general stochastic thermodynamics of RLC electrical networks built on top of a graph-theoretical representation of the dynamics commonly used by engineers. The network is: open, as it contains resistors and current and voltage sources, nonisothermal as resistors may be at different temperatures, and driven, as circuit elements may be subjected t

  22. G. Nikoghosyan, E. A. Kolganova, D. A. Sazonov, R. V. Jolos

    The theoretical approach to consideration of the Hamiltonian with pairing forces using a technique of the finite boson representation is developed. It is shown that a simultaneous description of the pairing vibrational state in $^{56}$Ni and the pairing rotational states with $T$=0 in the neighboring $N=Z$ nuclei is possible if the pairing Hamiltonian takes

  23. Saeed Hajizadeh

    In this paper, we would like to study the common randomness (CR) capacity of intertwined two-way channels, namely those whose marginal channel transition probabilities depends also on the signal they transmit. We bring a few special settings and provide constructive schemes with which the two nodes can agree upon a common randomness. We then provide an outer

  24. Vishnunarayanan Suresh, Edouard Pinsolle, Christian Lupien, Talia J. Martz-Oberlander

    We report {\it quantitative} microwave Faraday rotation measurements conducted with a high-mobility two-dimensional electron gas (2DEG) in a GaAs/AlGaAs semiconductor heterostructure. In a magnetic field, the Hall effect and the Faraday effect arise from the action of Lorentz force on electrons in the 2DEG. As with the Hall effect, a classical Faraday effect

  25. Christian Gorenflo, Lukasz Golab, Srinivasan Keshav

    Performance and scalability are major concerns for blockchains: permissionless systems are typically limited by slow proof of X consensus algorithms and sequential post-order transaction execution on every node of the network. By introducing a small amount of trust in their participants, permissioned blockchain systems such as Hyperledger Fabric can benefit

  26. Markus Wulfmeier, Abbas Abdolmaleki, Roland Hafner, Jost Tobias Springenberg

    The successful application of general reinforcement learning algorithms to real-world robotics applications is often limited by their high data requirements. We introduce Regularized Hierarchical Policy Optimization (RHPO) to improve data-efficiency for domains with multiple dominant tasks and ultimately reduce required platform time. To this end, we employ

  27. Iosif Pinelis

    The main result of the note describes certain optimal-score partitions, which can be interpreted as optimal resource allocations. This result is based on the fact that any nonnegative square matrix whose column sums are the same as the corresponding row sums can be represented as the sum of circuit matrices.

  28. Emilio Ojeda, Alfredo Pérez

    We present a new set of boundary conditions for General Relativity on AdS$_3$, where the dynamics of the boundary degrees of freedom are described by two independent left and right members of the Gardner hierarchy of integrable equations, also known as the "mixed KdV-mKdV" hierarchy. This integrable system has the very special property that simultaneously co

  29. Romakanta Bhattarai, Xiao Shen

    Silicon telluride (Si2Te3) is a silicon-based 2D chalcogenide with potential applications in optoelectronics. It has a unique crystal structure where Si atoms form Si-Si dimers to occupy the "metal" sites. In this paper, we report an ab initio computational study of its optical dielectric properties using the GW approximation and the Bethe-Salpeter equation

  30. Roman G. Smirnov, Kunpeng Wang

    We introduce a general Hamiltonian framework that appears to be a natural setting for the derivation of various production functions in economic growth theory, starting with the celebrated Cobb-Douglas function. Employing our method, we investigate some existing models and propose a new one as special cases of the general $n$-dimensional Lotka-Volterra syste

  31. Sridip Pal

    We use methods inspired from complex Tauberian theorems to make progress in understanding the asymptotic behavior of the magnitude of heavy-light-heavy three point coefficients rigorously. The conditions and the precise sense of averaging, which can lead to exponential suppression of such coefficients are investigated. We derive various bounds for the typica

  32. Yeoneung Kim, Hung V. Tran, Son N. T. Tu

    We study state-constraint static Hamilton-Jacobi equations in a sequence of domains $\{\Omega_k\}_{k \in \mathbb{N}}$ in $\mathbb{R}^n$ such that $\Omega_k \subset \Omega_{k+1}$ for all $k\in \mathbb{N}$. We obtain rates of convergence of $u_k$, the solution to the state-constraint problem in $\Omega_k$, to $u$, the solution to the corresponding problem in $

  33. Saeed Vatankhah, Shuang Liu, Rosemary A. Renaut, Xiangyun Hu

    The large-scale focusing inversion of gravity and magnetic potential field data using $L_1$-norm regularization is considered. The use of the randomized singular value decomposition methodology facilitates tackling the computational challenge that arises in the solution of these large-scale inverse problems. As such the powerful randomized singular value dec

  34. Bingnan Han, Yuxuan Lin, Yafang Yang, Nannan Mao

    Advanced microscopy and/or spectroscopy tools play indispensable role in nanoscience and nanotechnology research, as it provides rich information about the growth mechanism, chemical compositions, crystallography, and other important physical and chemical properties. However, the interpretation of imaging data heavily relies on the "intuition" of experienced

  35. Ekim Taylan Hanımeli, Isaac Tutusaus, Brahim Lamine, Alain Blanchard

    In this work, we investigate Newtonian cosmologies with a time-varying gravitational constant, $G(t)$. We examine whether such models can reproduce the low-redshift cosmological observations without a cosmological constant, or any other sort of explicit dark energy fluid. Starting with a modified Newton's second law, where $G$ is taken as a function of time,

  36. M. Damiano, G. Micela, G. Tinetti

    High-Resolution Spectroscopy (HRS) has been used to study the composition and dynamics of exoplanetary atmospheres. In particular, the spectrometer CRIRES installed on the ESO-VLT has been used to record high-resolution spectra in the Near-IR of gaseous exoplanets. Here we present a new automatic pipeline to analyze CRIRES data-sets. Said pipeline is based o

  37. Jiaxin Wu, Wenjuan Zhang

    Solving ground states of quantum many-body systems has been a long-standing problem in condensed matter physics. Here, we propose a new unsupervised machine learning algorithm to find the ground state of a general quantum many-body system utilizing the benefits of artificial neural network. Without assuming the specific forms of the eigenvectors, this algori

  38. Nicholas J. Willis, David A. Weinberg

    For real irreducible algebraic curves of the seventh degree, there are 22 types of singular points of multiplicity six, 174 types of singular points of multiplicity five, and at least 182 types of singular points of multiplicity four. For complex irreducible algebraic curves of the seventh degree, there are 12 types of singular points of multiplicity six, 92

  39. Andrei Alexandru, Paulo F. Bedaque, Siddhartha Harmalkar, Henry Lamm

    Simulations of gauge theories on quantum computers require the digitization of continuous field variables. Digitization schemes that uses the minimum amount of qubits are desirable. We present a practical scheme for digitizing $SU(3)$ gauge theories via its discrete subgroup $S(1080)$. The $S(1080)$ standard Wilson action cannot be used since a phase transit

  40. Uliyana Kubasova, Gabriel Murray, McKenzie Braley

    This work analyzes the efficacy of verbal and nonverbal features of group conversation for the task of automatic prediction of group task performance. We describe a new publicly available survival task dataset that was collected and annotated to facilitate this prediction task. In these experiments, the new dataset is merged with an existing survival task da

  41. Kieran Flatt, Stephen M. Barnett, Sarah Croke

    Multiple-copy state discrimination is a fundamental task in quantum information processing. If there are two, pure, non-orthogonal states then both local and collective schemes are known to reach the Helstrom bound, the maximum probability of successful discrimination allowed by quantum theory. For mixed states, it is known that only collective schemes can p

  42. Yu Zhang, Tammie Nelson, Sergei Tretiak

    When the interaction between a molecular system and confined light modes in an optical or plasmonic cavity is strong enough to overcome the dissipative process, hybrid light-matter states (polaritons) become the fundamental excitations in the system. The mixing between the light and matter characters modifies the photophysical and photochemical properties. E

  43. D. Hazra, Prosenjit Haldar, M. S. Laad, N. Tsavdaris

    In contrast to the Landau paradigm, a metal-insulator transition (MIT), driven purely by competition between itinerance and localization and unaccompanied by any conventional (e.g, magnetic) order-disorder instabilities, admits no obvious local order parameter. Here, we present a detailed analysis of the quantum criticality in magneto-transport data on the a

  44. Maciek Chociej, Peter Welinder, Lilian Weng

    We present the OpenAI Remote Rendering Backend (ORRB), a system that allows fast and customizable rendering of robotics environments. It is based on the Unity3d game engine and interfaces with the MuJoCo physics simulation library. ORRB was designed with visual domain randomization in mind. It is optimized for cloud deployment and high throughput operation.

  45. Claudio Marchi

    Let $G$ be a finite group of odd order. We show that if $\chi$ is an irreducible primitive character of $G$ then for all primes $p$ dividing the order of $G$ there is a conjugacy class such that the $p-$part of $\chi(1)$ divides the size of that conjugacy class. We also show that for some classes of groups the entire degree of an irreducible primitive charac

  46. M. Sh. Potashov, A. V. Yudin

    We propose a model kinetic system of the hydrogen atom (two levels plus continuum) under the conditions typical for atmospheres of Type IIP supernovae in the plateau stage. Despite the simplicity of this system, it describes realistically the basic properties of the complete system. Analysis shows that the ionization "freeze-out" effect is always manifest at

  47. Sh. A. Ayupov, A. A. Zaitov

    We introduce a metric on the space of monetary risk measure, which generates the point-wise convergence topology and extends the metric on the initial compactum.

  48. Sébastien Vaucher, Valerio Schiavoni, Pascal Felber

    The latest generation of Intel processors supports Software Guard Extensions (SGX), a set of instructions that implements a Trusted Execution Environment (TEE) right inside the CPU, by means of so-called enclaves. This paper presents Stress-SGX, an easy-to-use stress-test tool to evaluate the performance of SGX-enabled nodes. We build on top of the popular S

  49. John Wandeto, Henry Nyongesa, Yves Remond, Birgitta Dresp-Langley

    Radiologists use time series of medical images to monitor the progression of a patient condition. They compare information gleaned from sequences of images to gain insight on progression or remission of the lesions, thus evaluating the progress of a patient condition or response to therapy. Visual methods of determining differences between one series of imag

  50. Massimo Bernaschi, Alain Billoire, Andrea Maiorano, Giorgio Parisi

    Out of equilibrium relaxation processes show aging if they become slower as time passes. Aging processes are ubiquitous and play a fundamental role in the physics of glasses and spin glasses and in other applications (e.g. in algorithms minimizing complex cost/loss functions). The theory of aging in the out of equilibrium dynamics of mean-field spin glass mo

  51. Piotr Pikul

    While topology given by a linear order has been extensively studied, this cannot be said about the case when the order is given only locally. The aim of this paper is to fill this gap. We consider relation between local orderability and separation axioms and give characterisation of all connected, locally connected or compact locally ordered Hausdorff spaces

  52. Osonde Osoba, Bart Kosko

    Fuzzy cognitive maps (FCMs) model feedback causal relations in interwoven webs of causality and policy variables. FCMs are fuzzy signed directed graphs that allow degrees of causal influence and event occurrence. Such causal models can simulate a wide range of policy scenarios and decision processes. Their directed loops or cycles directly model causal feedb

  53. Vincenzo Afferrante, Axel Maas, Pascal Törek

    Scalar particles in the adjoint representation of a non-Abelian gauge theory play an important role in many scenarios beyond the standard model, especially of GUT type. For such theories manifestly gauge-invariant, massless, composite vector particles have been predicted, even at weak coupling, using the Fr\"ohlich-Morchio-Strocchi mechanism. We use lattice

  54. Ilya G. Ryabinkin, Robert A. Lang, Scott N. Genin, Artur F. Izmaylov

    An iterative version of the qubit coupled cluster (QCC) method [I.G. Ryabinkin et al., J. Chem. Theory Comput. 14, 6317 (2019)] is proposed. The new method seeks to find ground electronic energies of molecules on noisy intermediate-scale quantum (NISQ) devices. Each iteration involves a canonical transformation of the Hamiltonian and employs constant-size qu

  55. Edvin G. Idrisov, Thomas L. Schmidt

    We study nonequilibrium thermodynamic properties of a driven one-dimensional quantum fluid by combining nonlinear Luttinger liquid theory with the quantum kinetic equation. In particular, we derive an entropy production consistent with the laws of thermodynamics for a system subject to an arbitrary perturbation varying slowly in space and time. Working in a

  56. Irina V. Lebedeva, Andrey M. Popov

    The two-chain Frenkel-Kontorova model is applied for an analytical description of the energy and structure of the network of domain walls in bilayer graphene. Using this approach, the commensurate-incommensurate phase transition upon biaxial stretching of one of the graphene layers is considered. We demonstrate that formation of the equilateral triangular ne

  57. José C. Jiménez, Eduardo S. Fraga

    We perform the general relativistic stability analysis against radial oscillations of unpaired quark stars obtained using the equation of state for cold quark matter from perturbative QCD, the only free parameter being the renormalization scale. This approach consistently incorporates the effects of interactions and includes a built-in estimate of the inhere

  58. Nguyen-Bac Dang, Dragos Ghioca, Fei Hu, John Lesieutre

    Suppose that $f \colon X \dashrightarrow X$ is a dominant rational self-map of a smooth projective variety defined over ${\overline{\mathbf Q}}$. Kawaguchi and Silverman conjectured that if $P \in X({\overline{\mathbf Q}})$ is a point with well-defined forward orbit, then the growth rate of the height along the orbit exists, and coincides with the first dyna

  59. Sergio Albeverio, Francesco C. De Vecchi, Massimiliano Gubinelli

    We study a class of elliptic SPDEs with additive Gaussian noise on $\mathbb{R}^2 \times M$, with $M$ a $d$-dimensional manifold equipped with a positive Radon measure, and a real-valued non linearity given by the derivative of a smooth potential $V$, convex at infinity and growing at most exponentially. For quite general coefficients and a suitable regularit

  60. Pascal Traccucci, Luc Dumontier, Guillaume Garchery, Benjamin Jacot

    The quest for diversification has led to an increasing number of complex funds with a high number of strategies and non-linear payoffs. The new generation of Alternative Risk Premia (ARP) funds are an example that has been very popular in recent years. For complex funds like these, a Reverse Stress Test (RST) is regarded by the industry and regulators as a b

  61. Claudson F. Bornstein, Martin Charles Golumbic, Tanilson D. Santos, Uéverton S. Souza

    Golumbic, Lipshteyn, and Stern defined in 2009 the class of EPG graphs, the intersection graph class of edge paths on a grid. An EPG graph $G$ is a graph that admits a representation where its vertices correspond to paths in a grid $Q$, such that two vertices of $G$ are adjacent if and only if their corresponding paths in $Q$ have a common edge. If the paths

  62. H. Chau Nguyen, Fabian Bernards

    We analyse the entanglement dynamics of the two particles interacting through gravity in the recently proposed experiments aiming at testing quantum signatures for gravity [Phy. Rev. Lett 119, 240401 & 240402 (2017)]. We consider the open dynamics of the system under decoherence due to the environmental interaction. We show that as long as the coupling betwe

  63. Andrew Gould, Yoon-Hyun Ryu, Sebastiano Calchi Novati, Weicheng Zang

    At $q=1.81\pm 0.20 \times 10^{-5}$, KMT-2018-BLG-0029Lb has the lowest planet-host mass ratio $q$ of any microlensing planet to date by more than a factor of two. Hence, it is the first planet that probes below the apparent "pile-up" at $q=5$--10 $\times 10^{-5}$. The event was observed by {\it Spitzer}, yielding a microlens-parallax $\pi_{\rm E}$ measuremen

  64. Maxim Bazik, Brien Flewelling, Manoranjan Majji, Joseph Mundy

    Automated 3D pose estimation of satellites and other known space objects is a critical component of space situational awareness. Ground-based imagery offers a convenient data source for satellite characterization; however, analysis algorithms must contend with atmospheric distortion, variable lighting, and unknown reflectance properties. Traditional feature-

  65. Lipei Du, Ulrich Heinz

    Heavy-ion collisions at center-of-mass energies between 1 and 100 GeV/nucleon are essential to understand the phase diagram of QCD and search for its critical point. At these energies the net baryon density of the system can be high, and simulating its evolution becomes an indispensable part of theoretical modeling. We here present the (3+1)-dimensional diff

  66. A. J. Han Vinck, Kees A. Schouhamer Immink, Tadashi Wadayama, Van Khu Vu

    This year, 2019 we celebrate 30 years of our friendship between Asian and European scientists at the AEW11 in Rotterdam, the Netherlands. Many of the 1989 participants are also present at the 2019 event. This year we have many participants from different parts of Asia and Europe. It shows the importance of this event. It is a good tradition to pay a tribute

  67. Kimet Jusufi

    In this paper the problem of gravitational deflection of relativistic charged massive particles in slowly rotating Kerr-Newman black holes is considered. Toward this purpose we have used two methods: Firstly, we have applied the Gauss-Bonnet theorem (GBT) and the optical geometry to evaluate the deflection angle of charged particles. Secondly, we have presen

  68. Jiaoyan Chen, Ernesto Jimenez-Ruiz, Ian Horrocks

    Ontology-based knowledge bases (KBs) like DBpedia are very valuable resources, but their usefulness and usability is limited by various quality issues. One such issue is the use of string literals instead of semantically typed entities. In this paper we study the automated canonicalization of such literals, i.e., replacing the literal with an existing entity

  69. Lorin Baird, Xin Wang, Stetson Roof, J. E. Thomas

    We directly observe the hydrodynamic linear response of a unitary Fermi gas confined in a box potential and subject to a spatially periodic optical potential that is translated into the cloud at speeds ranging from subsonic to supersonic. We show that the time-dependent change of the density profile is sensitive to the thermal conductivity, which controls th

  70. M. Sh. Potashov, S. I. Blinnikov

    We investigate a simplified kinetic system of the hydrogen atom (two levels plus continuum) under conditions of a type IIP supernova at the plateau phase that realistically describes the basic properties of the complete system. We have found the Lyapunov function for the reduced system using which we have analytically obtained the ionization freeze-out effec

  71. Stephen James, Marc Freese, Andrew J. Davison

    PyRep is a toolkit for robot learning research, built on top of the virtual robotics experimentation platform (V-REP). Through a series of modifications and additions, we have created a tailored version of V-REP built with robot learning in mind. The new PyRep toolkit offers three improvements: (1) a simple and flexible API for robot control and scene manipu

  72. Yann Beilliard, Maxime Godard, Aggelos Ioannou, Astrinos Damianakis

    Current integration, architectural design and manufacturing technologies are not suited for the computing density and power efficiency requested by Exascale computing. New approaches in hardware architecture are thus needed to overcome the technological barriers preventing the transition to the Exascale era. In that scope, we report successful fabrication of

  73. Stefan Barańczuk

    Let $f_{1}, \ldots, f_{k}$ be polynomials defining an algebraic set in affine $n$-space over a finite field. Suppose $k>n$. We prove that there exists a system of polynomials $g_{1}, \ldots, g_{n}$, each being a linear combination with scalar coefficients of $f_{1}, \ldots, f_{k}$, defining the same algebraic set. In particular, one reduces the number of equ

  74. Yitwah Cheung, Nicolas Chevallier

    We extend two results about the ordinary continued fraction expansion to best simultaneous Diophantine approximations of vectors or matrices. The first is Levy-Khintchin Theorem about the almost sure growth rate of the denominators of the convergents. The second is a Theorem of Bosma, Hendrik and Wiedijk about the almost sure limit distribution of the sequen

  75. Barret Zoph, Ekin D. Cubuk, Golnaz Ghiasi, Tsung-Yi Lin

    Data augmentation is a critical component of training deep learning models. Although data augmentation has been shown to significantly improve image classification, its potential has not been thoroughly investigated for object detection. Given the additional cost for annotating images for object detection, data augmentation may be of even greater importance

  76. Xiaoyu Du, Xiangnan He, Fajie Yuan, Jinhui Tang

    As the core of recommender system, collaborative filtering (CF) models the affinity between a user and an item from historical user-item interactions, such as clicks, purchases, and so on. Benefited from the strong representation power, neural networks have recently revolutionized the recommendation research, setting up a new standard for CF. However, existi

  77. Thomas Fitoussi, Gustavo Medina-Tanco, Juan-Carlos D'Olivo

    Almost three decades ago, the Fly's Eye experiment recorded the most energetic cosmic-ray ever observed. With an energy of 320 EeV, this event is well beyond the suppression region of the ultra-high energy cosmic rays (UHECR) spectrum. Modern and larger observatories, with an exposure up to 60 times larger, have never observed an event with even remotely com

  78. Tao Xu, Yang Chen, Min Li, De-Xin Meng

    With the stationary solution assumption, we establish the connection between the nonlocal nonlinear Schr\"{o}dinger (NNLS) equation and an elliptic equation. Then, we obtain the general stationary solutions and discuss the relevance of their smoothness and boundedness to some integral constants. Those solutions, which cover the known results in the literatur

  79. Ka Wa Tsang, Archisman Ghosh, Anuradha Samajdar, Katerina Chatziioannou

    Gravitational wave echoes have been proposed as a smoking-gun signature of exotic compact objects with near-horizon structure. Recently there have been observational claims that echoes are indeed present in stretches of data from Advanced LIGO and Advanced Virgo immediately following gravitational wave signals from presumed binary black hole mergers, as well

  80. Jens Winkelmann, Adil Mughal, Denis Weaire, Stefan Hutzler

    A line of hard spheres confined by a transverse harmonic potential, with hard walls at its ends, exhibits a variety of buckled structures as it is compressed longitudinally. Here we show that these may be conveniently observed in a rotating liquid-filled tube (originally introduced by Lee et al. [T. Lee, K. Gizynski, and B. Grzybowski, Adv. Mater. 29, 170427

  81. Jiri Adamek

    For every finitary set functor F we demonstrate that free algebras carry a canonical partial order. In case F is bicontinuous, we prove that the cpo obtained as the conservative completion of the free algebra is the free completely iterative algebra. Moreover, the algebra structure of the latter is the unique continuous extension of the algebra structure of

  82. Moazzam Bilal, Andrey V Volotka, Randolf Beerwerth, Jan Rothhardt

    Large-scale relativistic calculations are performed for the transition energy and line strength of the $ 1s^{2} 2s 2p$ $^1P_{1} \,-\ 1s^{2} 2s^{2}$ $^1S_{0} $ transition in Be-like carbon. Based on the multiconfiguration Dirac-Hartree-Fock~(MCDHF) approach, different correlation models are developed to account for all major electron-electron correlation cont

  83. Urs Gebert, Bernhard Irsigler, Walter Hofstetter

    The engineering of topological non-trivial states of matter, using cold atoms, has made great progress in the last decade. Driven by experimental successes, it has become of major interest in the cold atom community. In this work we investigate the time-reversal invariant Hofstadter model with an additional confining potential. By calculating a local spin Ch

  84. Ralf Meyer

    We study the classification of group actions on C*-algebras up to equivariant KK-equivalence. We show that any group action is equivariantly KK-equivalent to an action on a simple, purely infinite C*-algebra. We show that a conjecture of Izumi is equivalent to an equivalence between cocycle conjugacy and equivariant KK-equivalence for actions of torsion-free

  85. A. D. Alhaidari

    We transform the Schr\"odinger wave equation to a nine-parameter Heun-type differential equation. Using our solutions of the latter in [J. Math. Phys. 59 (2018) 113507], we are able to identify the associated potential function, energy parameter, and write the corresponding wave function. Some of the solutions obtained correspond to new integrable quantum sy

  86. A. Nigoche-Netro, G. Ramos-Larios, P. Lagos, E. de la Fuente

    We study the behavior of the dynamical and stellar mass inside the effective radius of early-type galaxies (ETGs) as a function of environment considering Newtonian dynamics, different surface--brightness profiles, different initial mass functions (IMF) and different redshift ranges. We use several samples of ETGs --ranging from 19,000 to 98,000 objects-- fr

  87. Yan Liu, Lang Qin, Zhuo Cheng, Josh W. Goetze

    Chemical looping methane partial oxidation provides an energy and cost effective route for methane utilization. However, there is considerable CO2 co-production in state-of-the-art chemical looping systems, rendering a decreased productivity in value-added fuels or chemicals. In this work, we show that the co-production of CO2 can be dramatically suppressed

  88. Peter Poláčik, Pavol Quittner

    In studies of superlinear parabolic equations \begin{equation*} u_t=\Delta u+u^p,\quad x\in {\mathbb R}^N,\ t>0, \end{equation*} where $p>1$, backward self-similar solutions play an important role. These are solutions of the form $ u(x,t) = (T-t)^{-1/(p-1)}w(y)$, where $y:=x/\sqrt{T-t}$, $T$ is a constant, and $w$ is a solution of the equation $\Delta w-y\cd

  89. Felipe Elorrieta, Susana Eyheramendy, Wilfredo Palma

    Most time-series models assume that the data come from observations that are equally spaced in time. However, this assumption does not hold in many diverse scientific fields, such as astronomy, finance, and climatology, among others. There are some techniques that fit unequally spaced time series, such as the continuous-time autoregressive moving average (CA

  90. Sabah Al-Fedaghi

    Process modeling (PM) in software engineering involves a specific way of understanding the world. In this context, philosophical work is not merely intrinsically important; it can also stand up to some of the more established software engineering research metrics. The object-oriented methodology takes an object as the central concept of modeling. This paper

  91. Jiezhong Qiu, Yuxiao Dong, Hao Ma, Jian Li

    We study the problem of large-scale network embedding, which aims to learn latent representations for network mining applications. Previous research shows that 1) popular network embedding benchmarks, such as DeepWalk, are in essence implicitly factorizing a matrix with a closed form, and 2)the explicit factorization of such matrix generates more powerful em

  92. Jan Gerrit Horstmann, Bareld Wit, Gero Storeck, Claus Ropers

    The desire to exert active optical control over matter is a unifying theme across multiple scientific disciplines, as exemplified by all-optical magnetic switching, light-induced metastable or exotic phases of solids and the coherent control of chemical reactions. Typically, these approaches dynamically steer a system towards states or reaction products far

  93. Asja Derviškadić, Guglielmo Frigo, Mario Paolone

    Modern power systems are at risk of largely reducing the inertia of generation assets and prone to experience extreme dynamics. The consequence is that, during electromechanical transients triggered by large contingencies, transmission of electrical power may take place in a broad spectrum well beyond the single fundamental component. Traditional modeling ap

  94. Xiaoqian Wei, Jianying Yang, Xiangru Fan

    In this paper, two cooperative guidance laws based on two-point boundary value are designed to deal with the problem of cooperative encirclement and simultaneous attack under condition of both known target acceleration and unknown target acceleration. The only requirement for the multi-attacker communication network is that it contains a directed spanning tr

  95. Erik Bodin, Markus Kaiser, Ieva Kazlauskaite, Zhenwen Dai

    Bayesian optimization (BO) methods often rely on the assumption that the objective function is well-behaved, but in practice, this is seldom true for real-world objectives even if noise-free observations can be collected. Common approaches, which try to model the objective as precisely as possible, often fail to make progress by spending too many evaluations

  96. A. V. Kalameitsev, V. M. Kovalev, I. G. Savenko

    We report on novel valley acoustoelectric effect, which can arise in a 2D material, like a transition metal dichalcogenide monolayer, residing on a piezoelectric substrate. The essence of this effect lies in the emergence of a drag electric current (and a spin current) due to a propagating surface acoustic wave. This current consists of three contributions,

  97. Nicola Arcozzi, Pavel Mozolyako, Georgios Psaromiligkos, Alexander Volberg

    Coifman--Meyer multipliers represent a very important class of bi-linear singular operators, which were extensively studied and generalized. They have a natural multi-parameter counterpart. Decomposition of those operators into paraproducts, and, more generally to multi-parameter paraproducts is a staple of the theory. In this paper we consider weighted esti

  98. Daniel J. D'Orazio, Rosanne Di Stefano

    We explore a unique electromagnetic signature of stellar-mass compact-object binaries long before they are detectable in gravitational waves. We show that gravitational lensing of light emitting components of a compact-object binary, by the other binary component, could be detectable in the nearby universe. This periodic lensing signature could be detected f

  99. Amir R. Asadi, Emmanuel Abbe

    We derive generalization and excess risk bounds for neural nets using a family of complexity measures based on a multilevel relative entropy. The bounds are obtained by introducing the notion of generated hierarchical coverings of neural nets and by using the technique of chaining mutual information introduced in Asadi et al. NeurIPS'18. The resulting bounds

  100. K. Fitzgerald, L. -M. Browne, R. F. Butler

    Virtual observatories allow the means by which an astronomer is able to discover, access, and process data seamlessly, regardless of its physical location. However, steep learning curves are often required to become proficient in the software employed to access, analyse and visualise this trove of data. It would be desirable, for both research and educationa