September 2019 arXiv papers — page 49
Showing 4,801–4,900 of 13,841 papers
Yu-Chi Lin, Ludovic Righetti, Dmitry Berenson
Humanoid robots maintain balance and navigate by controlling the contact wrenches applied to the environment. While it is possible to plan dynamically-feasible motion that applies appropriate wrenches using existing methods, a humanoid may also be affected by external disturbances. Existing systems typically rely on controllers to reactively recover from dis
Jack Buttcane
We obtain the last of the standard Kuznetsov formulas for $SL(3,\Bbb{Z})$. In the previous paper, we were able to exploit the relationship between the positive-sign Bessel function and the Whittaker function to apply Wallach's Whittaker expansion; now we demonstrate the expansion of functions into Bessel functions for all four signs, generalizing Wallach's t
Richard Anantua, Razieh Emami, Abraham Loeb, Andrew Chael
We present a stationary, axisymmetric, self-similar semi-analytic model of magnetically dominated jet plasma based on force-free regions of a relativistic magnetohydrodynamic simulation. We use this model to illustrate how the composition of relativistic jet plasma can be determined, with special attention to the example of M87. In particular, we compute syn
Marco Oppio
The emergence of the concept of a causal fermion system is revisited and further investigated for the vacuum Dirac equation in Minkowski space. After a brief recap of the Dirac equation and its solution space, in order to allow for the effects of a possibly nonstandard structure of spacetime at the Planck scale, a regularization by a smooth cutoff in momentu
Marcos Eduardo Valle, Rodolfo Anibal Lobo
Hypercomplex-valued neural networks, including quaternion-valued neural networks, can treat multi-dimensional data as a single entity. In this paper, we introduce the quaternion-valued recurrent projection neural networks (QRPNNs). Briefly, QRPNNs are obtained by combining the non-local projection learning with the quaternion-valued recurrent correlation neu
Search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two $b$-jets in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
hep-exATLAS Collaboration
The results of a search for electroweakino pair production $pp \rightarrow \tilde\chi^\pm_1 \tilde\chi^0_2$ in which the chargino ($\tilde\chi^\pm_1$) decays into a $W$ boson and the lightest neutralino ($\tilde\chi^0_1$), while the heavier neutralino ($\tilde\chi^0_2$) decays into the Standard Model 125 GeV Higgs boson and a second $\tilde\chi^0_1$ are pres
Large- and Medium-Scale Anisotropies in the Arrival Directions of Cosmic Rays observed with KASCADE-Grande
astro-ph.HEMarkus Ahlers
We search for anisotropies in the arrival directions of cosmic rays observed by the KASCADE-Grande air shower experiment. The analysis is based on public data of about 23.7 million events with reconstructed primary energies above 1 PeV. We apply a novel maximum-likelihood reconstruction method for the cosmic ray anisotropy, that compensates for spurious anis
Zeljko Cuckovic, Sonmez Sahutoglu
For the open unit disc $\mathbb{D}$ in the complex plane, it is well known that if $\phi \in C(\overline{\mathbb{D}})$ then its Berezin transform $\widetilde{\phi}$ also belongs to $C(\overline{\mathbb{D}})$. We say that $\mathbb{D}$ is BC-regular. In this paper we study BC-regularity of some pseudoconvex domains in $\mathbb{C}^n$ and show that the boundary
Andreas M. Tillmann, Leif Kobbelt
We consider the problem of approximating a two-dimensional shape contour (or curve segment) using discrete assembly systems, which allow to build geometric structures based on limited sets of node and edge types subject to edge length and orientation restrictions. We show that already deciding feasibility of such approximation problems is NP-hard, and remain
Mostafa Annabestani
In this article we show that for any quantum walker with \textit{m}-dimensional coin subspace, we have $m^2\times m^2$ specific constant matrix $\mathcal{C}$ where it completely determines the asymptotic reduced density matrix of the walker. We show that for any initial state with $P_0$ projector, reduced density matrix, can be obtained by $Tr_1\left(P_0\oti
RELICS: Spectroscopy of gravitationally-lensed $z\simeq 2$ reionization-era analogs and implications for CIII] detections at $z>6$
astro-ph.GARamesh Mainali, Daniel P Stark, Mengtao Tang, Jacopo Chevallard
Recent observations have revealed the presence of strong CIII] emission (EW$_{\rm{CIII]}}>20$ \r{A}) in $z>6$ galaxies, the origin of which remains unclear. In an effort to understand the nature of these line emitters, we have initiated a survey targeting CIII] emission in gravitationally-lensed reionization era analogs identified in HST imaging of clusters
ELMAG 3.01: A three-dimensional Monte Carlo simulation of electromagnetic cascades on the extragalactic background light and in magnetic fields
astro-ph.HEM. Blytt, M. Kachelriess, S. Ostapchenko
The version 3.01 of ELMAG, a Monte Carlo program for the simulation of electromagnetic cascades initiated by high-energy photons and electrons interacting with extragalactic background light (EBL), is presented. Pair production and inverse Compton scattering on EBL photons as well as synchrotron losses are implemented using weighted sampling of the cascade d
Katrin Becker, Melanie Becker, Daniel Butter, William D. Linch
We construct 5D, N = 1 supergravity in a 4D, N = 1 superspace with an extra bosonic coordinate. This represents four of the supersymmetries and the associated Poincar\'e symmetries manifestly. The remaining four supersymmetries and the rest of the Poincar\'e symmetries are represented linearly but not manifestly. In the linearized approximation, the action r
Vassilis G. Papanicolaou
We present certain results on the direct and inverse spectral theory of the Jacobi operator with complex periodic coefficients. For instance, we show that any $N$-th degree polynomial whose leading coefficient is $(-1)^N$ is the Hill discriminant of finitely many discrete $N$-periodic Schrödinger operators (Theorem 1). Also, in the case where the spectrum is
Nattalie Tamam
We prove a modified version for a conjecture of Weiss from 2004. Let $G$ be a semisimple real algebraic group defined over $\mathbb{Q}$, $\Gamma$ be an arithmetic subgroup of $G$. A trajectory in $G/\Gamma$ is divergent if eventually it leaves every compact subset, and is obvious divergent if there is a finite collection of algebraic data which cause the div
D. J. Mullan, J. MacDonald
The onset of cool massive winds in evolved giants is correlated with an evolutionary feature on the red giant branch known as the bump. Also at the bump, shear instability in the star leads to magnetic fields that occur preferentially on small length scales. Pneuman (1983) has suggested that the emergence of small scale flux tubes in the Sun can give rise to
Modification of Turbulent Boundary Layer Coherent Structures with Drag Reducing Polymer Solution
physics.flu-dynYasaman Farsiani, Zeeshan Saeed, Balaji Jayaraman, Brian R. Elbing
The modification of dominant coherent structures that extend through the log-region of a drag reduced turbulent boundary layer is studied via examination of two-point correlations from time-resolved particle-image-velocimetry. Measurements were acquired in polymer oceans (uniform concentration) at drag reduction levels corresponding to the low drag reduction
Matthew P. A. Jones, Robert M. Potvliege, Michael Spannowsky
We consider the role of high-lying Rydberg states of simple atomic systems such as $^1$H in setting constraints on physics beyond the Standard Model. We obtain highly accurate bound states energies for a hydrogen atom in the presence of an additional force carrier (the energy levels of the Hellmann potential). These results show that varying the size and sha
CMS Collaboration
The running of the top quark mass is experimentally investigated for the first time. The mass of the top quark in the modified minimal subtraction ($\mathrm{\overline{MS}}$) renormalization scheme is extracted from a comparison of the differential top quark-antiquark ($\mathrm{t\overline{t}}$) cross section as a function of the invariant mass of the $\mathrm
A. Avsar, H. Ochoa, F. Guinea, B. Ozyilmaz
After the first unequivocal demonstration of spin transport in graphene (Tombros et al., 2007), surprisingly at room temperature, it was quickly realized that this novel material was relevant for both fundamental spintronics and future applications. Over the decade since, exciting results have made the field of graphene spintronics blossom, and a second gene
Tao Liu, Juhao Wu
The meromorphic function $W(s)$ introduced in the Riemann-Zeta function $\zeta(s) = W(s) \zeta(1-s)$ maps the line of $s = 1/2 + it$ onto the unit circle in $W$-space. $|W(s)| = 0$ gives the trivial zeroes of the Riemann-Zeta function $\zeta(s)$. In the range: $0 < |W(s)| \neq 1$, $\zeta(s)$ does not have nontrivial zeroes. $|W(s)|=1$ is the necessary condit
Ivan I. Vrubel, Anastasiia A. Pervishko, Dmitry Yudin, Biplab Sanyal
The study of zinc oxide, within the homogeneous electron gas approximation, results in overhybridization of zinc $3d$ shell with oxygen $2p$ shell, a problem shown for most transition metal chalcogenides. This problem can be partially overcome by using LDA+$U$ (or, GGA+$U$) methodology. However, in contrast to the zinc $3d$ orbital, Hubbard type correction i
Hybrid Inexact BCD for Coupled Structured Matrix Factorization in Hyperspectral Super-Resolution
eess.SPRuiyuan Wu, Hoi-To Wai, Wing-Kin Ma
This paper develops a first-order optimization method for coupled structured matrix factorization (CoSMF) problems that arise in the context of hyperspectral super-resolution (HSR) in remote sensing. To best leverage the problem structures for computational efficiency, we introduce a hybrid inexact block coordinate descent (HiBCD) scheme wherein one coordina
Aidan I Brown, David A Sivak
Biomolecular machines are protein complexes that convert between different forms of free energy. They are utilized in nature to accomplish many cellular tasks. As isothermal nonequilibrium stochastic objects at low Reynolds number, they face a distinct set of challenges compared to more familiar human-engineered macroscopic machines. Here we review central q
Kelvin-Helmholtz versus Tearing Instability: What Drives Turbulence in Stochastic Reconnection?
astro-ph.HEGrzegorz Kowal, Diego A. Falceta-Gonçalves, Alex Lazarian, Ethan T. Vishniac
Over the last few years it became clear that turbulent magnetic reconnection and magnetized turbulence are inseparable. It was not only shown that reconnection is responsible for violating the frozen-in condition in turbulence, but also that stochastic reconnection in 3D generates turbulence by itself. The actual mechanism responsible for this driving is sti
Hannah Guggiari, Alex Scott
For every $n\in\mathbb{N}$ and $k\geq2$, it is known that every $k$-edge-colouring of the complete graph on $n$ vertices contains a monochromatic connected component of order at least $\frac{n}{k-1}$. For $k\geq3$, it is known that the complete graph can be replaced by a graph $G$ with $\delta(G)\geq(1-\varepsilon_k)n$ for some constant $\varepsilon_k$. In t
Qi Lyu, Xiao Fu
Multiview analysis aims at extracting shared latent components from data samples that are acquired in different domains, e.g., image, text, and audio. Classic multiview analysis, e.g., canonical correlation analysis (CCA), tackles this problem via matching the linearly transformed views in a certain latent domain. More recently, powerful nonlinear learning t
Venkateswararao Cherukuri, Vijay Kumar BG, Raja Bala, Vishal Monga
Vessel segmentation of retinal images is a key diagnostic capability in ophthalmology. This problem faces several challenges including low contrast, variable vessel size and thickness, and presence of interfering pathology such as micro-aneurysms and hemorrhages. Early approaches addressing this problem employed hand-crafted filters to capture vessel structu
Ikuya Kaneko, Shin-ya Koyama
The second author formulated quantum unique ergodicity for Eisenstein series in the prime level aspect in "Equidistribution of Eisenstein series in the level aspect", Commun. Math. Phys. 289(3), 1131-1150 (2009). We point out errors and correct the proofs with partially weakened claims. This article of corrigendum and addendum comprises three sections. Secti
Hadi Sarieddeen, Nasir Saeed, Tareq Y. Al-Naffouri, Mohamed-Slim Alouini
Terahertz (THz)-band communications are celebrated as a key enabling technology for next-generation wireless systems that promises to integrate a wide range of data-demanding and delay-sensitive applications. Following recent advancements in optical, electronic, and plasmonic transceiver design, integrated, adaptive, and efficient THz systems are no longer f
Salvatore Mignemi, Giacomo Rosati
We show in general that for a relativistic theory with curved momentum space, i.e.~a theory with deformed relativistic symmetries, the physical velocity of particles coincides with their group velocity. This clarifies a long-standing question about the discrepancy between coordinate and group velocity for this kind of theories. The first evidence that this w
Peixin Chang, Shuijing Liu, Haonan Chen, Katherine Driggs-Campbell
We explore the interpretation of sound for robot decision making, inspired by human speech comprehension. While previous methods separate sound processing unit and robot controller, we propose an end-to-end deep neural network which directly interprets sound commands for visual-based decision making. The network is trained using reinforcement learning with a
Andrew Repp, István Szapudi
A reliable model of galaxy bias is necessary for interpreting data from future dense galaxy surveys. Conventional bias models are inaccurate, in that they can yield unphysical results ($\delta_g < -1$) for voids that might contain half of the available cosmological information. For this reason, we present a physically-motivated bias model based on an analogy
Ahmet Coskuner, Andrea Mitridate, Andres Olivares, Kathryn M. Zurek
Dirac materials, because of their small ${\cal O}(\mbox{meV})$ band gap, are a promising target for dark photon-mediated scattering and absorption of light dark matter. In this paper, we characterize the daily modulation rate of dark matter interacting with a Dirac material due to anisotropies in their crystal structure. We show that daily modulation is an $
Yakov Faerman, Amiel Sternberg, Christopher F. McKee
We construct a new analytic phenomenological model for the extended circumgalactic material (CGM) of $L^*$ galaxies. Our model reproduces the OVII/OVIII absorption observations of the Milky Way (MW) and the OVI measurements reported by the COS-Halos and eCGM surveys. The warm/hot gas is in hydrostatic equilibrium in a MW gravitational potential, and we adopt
Makoto Natsuume, Takashi Okamura
Recently, it is shown that many Green's functions are not unique at special points in complex momentum space using AdS/CFT. This phenomenon is similar to the pole-skipping in holographic chaos, and the special points are typically located at $\omega_n = -(2\pi T)ni$ with appropriate values of complex wave number $q_n$. We study finite-coupling corrections to
Collusion of Interactions and Disorder at the Superfluid-Insulator Transition: A Dirty 2d Quantum Critical Point
cond-mat.str-elHart Goldman, Alex Thomson, Laimei Nie, Zhen Bi
We study the stability of the Wilson-Fisher fixed point of the quantum $\mathrm{O}(2N)$ vector model to quenched disorder in the large-$N$ limit. While a random mass is strongly relevant at the Gaussian fixed point, its effect is screened by the strong interactions of the Wilson-Fisher fixed point. This enables a perturbative renormalization group study of t
Improving wafer-scale Josephson junction resistance variation in superconducting quantum coherent circuits
quant-phJ. M. Kreikebaum, K. P. O'Brien, A. Morvan, I. Siddiqi
Quantum bits, or qubits, are an example of coherent circuits envisioned for next-generation computers and detectors. A robust superconducting qubit with a coherent lifetime of $O$(100 $\mu$s) is the transmon: a Josephson junction functioning as a non-linear inductor shunted with a capacitor to form an anharmonic oscillator. In a complex device with many such
Neil Christensen, Bryan Field, Annie Moore, Santiago Pinto
We further develop the massive constructive theory of the Standard Model and use it to calculate the amplitude and squared amplitude for all two-body decays, a collection of weak three-body decays, as well as Higgs decay to four neutrinos. We compare our results with those from Feynman diagrams and find complete agreement. We show that in all the cases consi
Tobias Buck
The Milky Way's stellar disk exhibits a bimodality in the [Fe/H] vs. [$\alpha$/Fe] plane, showing a distinct high-$\alpha$ and low-$\alpha$ sequence whose origin is still under debate. We examine the [Fe/H]-[$\alpha$/Fe] abundance plane in cosmological hydrodynamical simulations of Milky Way like galaxies from the NIHAO-UHD project and show that the bimodal
Visual Orbits of Spectroscopic Binaries with the CHARA Array. II. The eclipsing binary HD 185912
astro-ph.SRKathryn V. Lester, Douglas R. Gies, Gail H. Schaefer, Christopher D. Farrington
We present the visual orbit of the double-lined eclipsing binary, HD 185912, from long baseline interferometry with the CHARA Array. We also obtain echelle spectra from the Apache Point observatory to update the spectroscopic orbital solution and analyze new photometry from Burggraaff et al. to model the eclipses. By combining the spectroscopic and visual or
Thomas D. Rueter, Thomas G. Rizzo
The nature of dark matter (DM) and how it might interact with the particles of the Standard Model (SM) is an ever-growing mystery. It is possible that the existence of new `dark sector' forces, yet undiscovered, are the key to solving this fundamental problem, and one might hope that in the future such forces might even be `unified' with the ones we already
S. Marino, M. C. Wyatt, G. M. Kennedy, M. Kama
Low mass stars might offer today the best opportunities to detect and characterise planetary systems, especially those harbouring close-in low mass temperate planets. Among those stars, TRAPPIST-1 is exceptional since it has seven Earth-sized planets, of which three could sustain liquid water on their surfaces. Here we present new and deep ALMA observations
Jacob L. Bourjaily, Enrico Herrmann, Cameron Langer, Andrew J. McLeod
We extend the applications of prescriptive unitarity beyond the planar limit to provide local, polylogarithmic, integrand-level representations of six-particle MHV scattering amplitudes in both maximally supersymmetric Yang-Mills theory and gravity. The integrand basis we construct is diagonalized on a spanning set of non-vanishing leading singularities that
Xiao-Xiao Zhang, Marcel Franz
Alternating current RLC electric circuits form an accessible and highly tunable platform simulating Hermitian as well as non-Hermitian (nH) quantum systems. We propose here a circuit realization of nH Dirac and Weyl Hamiltonians subject to time-reversal invariant pseudo-magnetic field, enabling the exploration of novel nH physics. We identify the low-energy
Fabio Apruzzi, Craig Lawrie, Ling Lin, Sakura Schafer-Nameki
In arXiv:1906.11820 and arXiv:1907.05404 we proposed an approach based on graphs to characterize 5d superconformal field theories (SCFTs), which arise as compactifications of 6d $\mathcal{N}= (1,0)$ SCFTs. The graphs, so-called combined fiber diagrams (CFDs), are derived using the realization of 5d SCFTs via M-theory on a non-compact Calabi--Yau threefold wi
Federico Castillo, Fu Liu
In the special case of braid fans, we give a combinatorial formula for the Berline-Vergne's construction for an Euler-Maclaurin type formula that computes number of lattice points in polytopes. Our formula is obtained by computing a symmetric expression for the Todd class of the permutohedral variety. By showing that this formula does not always have positiv
Bhavini Singh, Lalit Rajendran, Pavlos P Vlachos, Sally Bane
The cooling process associated with the flow induced by a spark plasma discharge generated between a pair of electrodes is measured using stereoscopic particle image velocimetry (S-PIV) and background oriented schlieren (BOS). Density measurements show that the hot gas kernel initially cools fast by convective cooling, followed by a slower cooling process. T
Global regularity for solutions of the three dimensional Navier-Stokes equation with almost two dimensional initial data
math.APEvan Miller
In this paper, we will prove a new result that guarantees the global existence of solutions to the Navier--Stokes equation in three dimensions when the initial data is sufficiently close to being two dimensional. This result interpolates between the global existence of smooth solutions for the two dimensional Navier--Stokes equation with arbitrarily large in
Claudiu Raicu, Steven V Sam
We extend the theory of Koszul modules to the bi-graded case, and prove a vanishing theorem that allows us to show that the Canonical Ribbon Conjecture of Bayer and Eisenbud holds over a field of characteristic zero or at least equal to the Clifford index. Our results confirm a conjecture of Eisenbud and Schreyer regarding the characteristics where the gener
Ikko Hamamura, Takashi Imamichi
The advent of cloud quantum computing has led to the rapid development of quantum algorithms. In particular, it is necessary to study variational quantum-classical hybrid algorithms, which are executable on noisy intermediate-scale quantum (NISQ) computers. Evaluations of observables appear frequently in the variational quantum-classical hybrid algorithms fo
Masanori Hanada, Antal Jevicki, Cheng Peng, Nico Wintergerst
In the weak coupling limit of ${\rm SU}(N)$ Yang-Mills theory and the ${\rm O}(N)$ vector model, explicit state counting allows us to demonstrate the existence of a partially deconfined phase: $M$ of $N$ colors deconfine, and $\frac{M}{N}$ gradually grows from zero (confinement) to one (complete deconfinement). We point out that the mechanism admits a simple
John Campbell, Tobias Neumann
Without proper control of numerical and methodological errors in theoretical predictions at the per mille level it is not possible to study the effect of input parameters in current hadron-collider measurements at the required precision. We present a new version of the parton-level code MCFM that achieves this requirement through its highly-parallelized natu
Jacob Kahn, Ann Lee, Awni Hannun
We revisit self-training in the context of end-to-end speech recognition. We demonstrate that training with pseudo-labels can substantially improve the accuracy of a baseline model. Key to our approach are a strong baseline acoustic and language model used to generate the pseudo-labels, filtering mechanisms tailored to common errors from sequence-to-sequence
William J. Huggins, Joonho Lee, Unpil Baek, Bryan O'Gorman
Variational algorithms for strongly correlated chemical and materials systems are one of the most promising applications of near-term quantum computers. We present an extension to the variational quantum eigensolver that approximates the ground state of a system by solving a generalized eigenvalue problem in a subspace spanned by a collection of parametrized
Mehrnaz Anvari, Leonardo Rydin Gorjão, Marc Timme, Dirk Witthaut
The frequency constitutes a key state variable of electrical power grids. However, as the frequency is subject to several sources of fluctuations, ranging from renewable volatility to demand fluctuations and dispatch, it is strongly dynamic. Yet, the statistical and stochastic properties of the frequency fluctuation dynamics are far from fully understood. He
Dmitry Budker, Victor V. Flambaum, Xunyu Liang, Ariel Zhitnitsky
We advocate an idea that the presence of the daily and annual modulations of the axion flux on the Earth surface may dramatically change the strategy of the axion searches. Our computations are based on the so-called Axion Quark Nugget (AQN) dark matter model which was originally put forward to explain the similarity of the dark and visible cosmological matt
Polnop Samutpraphoot, Tamara Ðorđević, Paloma L. Ocola, Hannes Bernien
We demonstrate photon-mediated interactions between two individually trapped atoms coupled to a nanophotonic cavity. Specifically, we observe superradiant line broadening when the atoms are resonant with the cavity, and level repulsion when the cavity is coupled to the atoms in the dispersive regime. Our approach makes use of individual control over the inte
Grzegorz Świderski, Bartosz Trojan
For Jacobi parameters belonging to one of the three classes: asymptotically periodic, periodically modulated and the blend of these two, we study the asymptotic behavior of the Christoffel functions and the scaling limits of the Christoffel-Darboux kernel. We assume regularity of Jacobi parameters in terms of the Stolz class. We emphasize that the first clas
Simultaneous Optical Transmission Spectroscopy of a Terrestrial, Habitable-Zone Exoplanet with Two Ground-Based Multi-Object Spectrographs
astro-ph.EPHannah Diamond-Lowe, Zachory Berta-Thompson, David Charbonneau, Jason Dittmann
Investigating the atmospheres of rocky exoplanets is key to performing comparative planetology between these worlds and the terrestrial planets that reside in the inner solar system. Terrestrial exoplanet atmospheres exhibit weak signals, and attempting to detect them pushes at the boundaries of what is possible for current instrumentation. We focus on the h
Joe Gale, Amri Wandel, Hugh Hill
The steady advances in computer performance and in programming raise the concern that the ability of computers would overtake that of the human brain, an occurrence termed "the Singularity". While comparing the size of the human brain and the advance in computer capacity, the Singularity has been estimated to occur within a few decades although the capacity
Jesse Chan
Reduced order models of nonlinear conservation laws in fluid dynamics do not typically inherit stability properties of the full order model. We introduce projection-based hyper-reduced models of nonlinear conservation laws which are globally conservative and inherit a semi-discrete entropy inequality independently of the choice of basis and choice of paramet
Tomographic measurement of the intergalactic gas pressure through galaxy-tSZ cross-correlations
astro-ph.CONick Koukoufilippas, David Alonso, Maciej Bilicki, John A. Peacock
We cross-correlate maps of the thermal Sunyaev-Zeldovich (tSZ) Compton-$y$ parameter published by Planck with the projected distribution of galaxies in a set of low-redshift tomographic bins. We use the nearly full-sky 2MASS Photometric Redshift and WISE $\times$ SuperCOSMOS public catalogues, covering the redshift range $z\lesssim0.4$. Our measurements allo
Joel David Hamkins, Kameryn J. Williams
We introduce the $\Sigma_1$-definable universal finite sequence and prove that it exhibits the universal extension property amongst the countable models of set theory under end-extension. That is, (i) the sequence is $\Sigma_1$-definable and provably finite; (ii) the sequence is empty in transitive models; and (iii) if $M$ is a countable model of set theory
Paolo Rosson, Martin Kiffner, Jordi Mur-Petit, Dieter Jaksch
We use state-of-the-art density matrix renormalization group calculations in the canonical ensemble to determine the phase diagram of the dipolar Bose-Hubbard model on a finite cylinder. We consider several observables that are accessible in typical optical lattice setups and assess how well these quantities perform as order parameters. We find that, especia
Planet Hunters TESS I: TOI 813, a subgiant hosting a transiting Saturn-sized planet on an 84-day orbit
astro-ph.EPN. L. Eisner, O. Barragán, S. Aigrain, C. Lintott
We report on the discovery and validation of TOI 813b (TIC 55525572 b), a transiting exoplanet identified by citizen scientists in data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by the Planet Hunters TESS project. The host star is a bright (V = 10.3 mag) subgiant ($R_\star=1.94\,R_\odot$, $M_\star=1.32\,M_\odot$
David Burns, Rob de Jeu, Herbert Gangl, Alexander D. Rham
We develop methods for constructing explicit generators, modulo torsion, of the K_3-groups of imaginary quadratic number fields. These methods are based on either tessellations of hyperbolic 3-space or on direct calculations in suitable pre-Bloch groups, and lead to the very first proven examples of explicit generators, modulo torsion, of any infinite K_3-gr
Jonas M. Kübler, Andrew Arrasmith, Lukasz Cincio, Patrick J. Coles
Variational hybrid quantum-classical algorithms (VHQCAs) have the potential to be useful in the era of near-term quantum computing. However, recently there has been concern regarding the number of measurements needed for convergence of VHQCAs. Here, we address this concern by investigating the classical optimizer in VHQCAs. We introduce a novel optimizer cal
Aniruddh Raghu, Maithra Raghu, Samy Bengio, Oriol Vinyals
An important research direction in machine learning has centered around developing meta-learning algorithms to tackle few-shot learning. An especially successful algorithm has been Model Agnostic Meta-Learning (MAML), a method that consists of two optimization loops, with the outer loop finding a meta-initialization, from which the inner loop can efficiently
Rui Chen, Mansur Arief, Weiyang Zhang, Ding Zhao
Proving ground has been a critical component in testing and validation for Connected and Automated Vehicles (CAV). Although quite a few world-class testing facilities have been under construction over the years, the evaluation of proving grounds themselves as testing approaches has rarely been studied. In this paper, we present the first attempt to systemati
André Rodrigues, Hugo Nicolau, Kyle Montague, João Guerreiro
Blind people face significant challenges when using smartphones. The focus on improving non-visual mobile accessibility has been at the level of touchscreen access. Our research investigates the challenges faced by blind people in their everyday usage of mobile phones. In this paper, we present a set of studies performed with the target population, novices a
Daichi Kashino, Simon J. Lilly, Takatoshi Shibuya, Masami Ouchi
We present evidence that a region of high effective Ly$\alpha$ optical depth at $z\sim5.7$ is associated with an underdense region at the tail end of cosmic reionization. We carried out a survey of Lyman-break Galaxies (LBGs) using Subaru Hyper Suprime-Cam in the field of the $z=5.98$ quasar J0148+0600, whose spectrum presents an unusually long ($\sim160 \ma
Clément Le Priol, Julien Chopin, Pierre Le Doussal, Laurent Ponson
The propagation of a crack front in disordered materials is jerky and characterized by bursts of activity, called avalanches. These phenomena are the manifestation of an out-of-equilibrium phase transition originated by the disorder. As a result avalanches display universal scalings which are however difficult to characterize in experiments at finite drive.
Denis Kislov, Denis Novitsky, Alexey Kadochkin, Dmitrii Redka
Structured environment controls dynamics of light-matter interaction processes via modified local density of electromagnetic states. In typical scenarios, where nanosecond-scale fluorescent processes are involved, mechanical conformational changes of the environment during the interaction processes can be safely neglected. However, slow decaying phosphoresce
Quenching of an antiferromagnet into high resistivity states using electrical or ultrashort optical pulses
physics.app-phZdeněk Kašpar, Miloslav Surýnek, Jan Zubáč, Filip Krizek
Ultra-fast dynamics, insensitivity to external magnetic fields, or absence of magnetic stray fields are examples of properties that make antiferromagnets of potential use in the development of spintronic devices. Similar to their ferromagnetic counterparts, antiferromagnets can store information in the orientations of the collective magnetic order vector. Ho
Sohail, Ujjwal Sen
We provide a method for witnessing nonseparability of quantum processes on shared systems, which uses the channel-state duality. The method uses a maximally entangled state as a resource. We show that using the resource provides significant advantage over the corresponding protocol for nonseparability detection without the resource.
Adrien Bennetot, Jean-Luc Laurent, Raja Chatila, Natalia Díaz-Rodríguez
Many high-performance models suffer from a lack of interpretability. There has been an increasing influx of work on explainable artificial intelligence (XAI) in order to disentangle what is meant and expected by XAI. Nevertheless, there is no general consensus on how to produce and judge explanations. In this paper, we discuss why techniques integrating conn
Lateral Josephson effect on the surface of Co$_3$Sn$_2$S$_2$ magnetic Weyl semimetal
cond-mat.mes-hallO. O. Shvetsov, V. D. Esin, Yu. S. Barash, A. V. Timonina
We experimentally study lateral electron transport between two 5~$\mu$m spaced superconducting indium leads on a top of magnetic Weyl semimetal Co$_3$Sn$_2$S$_2$. For the disordered magnetic state of Co$_3$Sn$_2$S$_2$ crystal, we only observe the Andreev reflection in the proximity of each of the leads, which is indicative of highly transparent In-Co$_3$Sn$_
Lun Huang, Wenmin Wang, Yaxian Xia, Jie Chen
Recent neural models for image captioning usually employ an encoder-decoder framework with an attention mechanism. However, the attention mechanism in such a framework aligns one single (attended) image feature vector to one caption word, assuming one-to-one mapping from source image regions and target caption words, which is never possible. In this paper, w
Qiang Zheng, Lingzao Zeng, Zhendan Cao, George Em Karniadakis
A fundamental problem in geostatistical modeling is to infer the heterogeneous geological field based on limited measurements and some prior spatial statistics. Semantic inpainting, a technique for image processing using deep generative models, has been recently applied for this purpose, demonstrating its effectiveness in dealing with complex spatial pattern
Radu Slobodeanu
We present a steady Euler flow on the round 3-sphere whose velocity vector field has the property of having two independent first integrals, being tangent to the fibres of an almost submersion onto the 2-sphere. This submersion turns out to be a critical point for the quartic Faddeev-Skyrme model with a standard potential.
Emmanuel Breuillard, Péter P. Varjú
We study the Markov chain $x_{n+1}=ax_n+b_n$ on a finite field $\mathbb{F}_p$, where $a \in \mathbb{F}_p$ is fixed and $b_n$ are independent and identically distributed random variables in $\mathbb{F}_p$. Conditionally on the Riemann hypothesis for all Dedekind zeta functions, we show that the chain exhibits a cut-off phenomenon for most primes $p$ and most
Philipp Mertsch, Markus Ahlers
The distribution of arrival directions of cosmic rays is remarkably isotropic, which is a consequence of their repeated scattering in magnetic fields. Yet, high-statistics observatories like IceCube and HAWC have revealed the presence of small-scale structures at levels of 1 part in 10,000 at hundreds of TeV, which are not expected in typical diffusion model
Lynn B. Wilson, Li-Jen Chen, Shan Wang, Steven J. Schwartz
A statistical analysis of 15,210 electron velocity distribution function (VDF) fits, observed within $\pm$2 hours of 52 interplanetary (IP) shocks by the $Wind$ spacecraft near 1 AU, is presented. This is the second in a three-part series on electron VDFs near IP shocks. The electron velocity moment statistics for the dense, low energy core, tenuous, hot hal
Dmitri Vassilevich
We critically review the possibilities of a repulsive Casimir interaction between materials which carry Chern-Simons surface actions for the electromagnetic field.
Brian A. Powell
Authenticated lateral movement via compromised accounts is a common adversarial maneuver that is challenging to discover with signature- or rules-based intrusion detection systems. In this work a behavior-based approach to detecting malicious logins to novel systems indicative of lateral movement is presented, in which a user's historical login activity is u
Louis Brown, Stefan Steinerberger
We discuss the classical problem of measuring the regularity of distribution of sets of $N$ points in $\mathbb{T}^d$. A recent line of investigation is to study the cost ($=$ mass $\times$ distance) necessary to move Dirac measures placed in these points to the uniform distribution. We show that Kronecker sequences satisfy optimal transport distance in $d \g
Jose Beltrán Jiménez, Lavinia Heisenberg, Damianos Iosifidis, Alejandro Jiménez-Cano
In this Letter we consider a general quadratic parity-preserving theory for a general flat connection. Imposing a local symmetry under the general linear group singles out the general teleparallel equivalent of General Relativity carrying both torsion and non-metricity. We provide a detailed discussion on the teleparallel equivalents of General Relativity an
Arun Maiti
Quasi-vertex-transitive maps are the homogeneous maps on the plane with finitely many vertex orbits under the action of their automorphism groups. We show that there exist quasi-vertex-transitive maps of types $[p^3, 3]$ for $p \equiv 1$ (mod $6$), but there doesn't exist vertex-transitive map of such types. In particular, we determine the surface with the l
Shun'ya Mizoguchi, Hajime Otsuka, Hitomi Tashiro
It has been known for some time that a hermitian matrix model with a Penner-like potential yields as its large-N free energy the prepotential of N=2 N_f=2 SU(2) SUSY gauge theory. We give a rigorous proof that a unitary matrix model with the identical potential also yields the same prepotential, although the parameter identifications are slightly different.
Hongkuan Zhang, Yi Chen, Xiaoning Liu, Gengkai Hu
Elastic material with its elastic tensor losing minor symmetry is considered impossible without introducing artificially body torque. Here we demonstrate the feasibility of such material by introducing rotational resonance, the amplified rotational inertia of the microstructure during dynamical loading breaks naturally the shear stress symmetry, without reso
Robert Brijder, Lorenzo Traldi
A graph $G$ has an associated multimatroid $\mathcal{Z}_3(G)$, which is equivalent to the isotropic system of $G$ studied by Bouchet. In previous work it was shown that $G$ is a circle graph if and only if for every field $\mathbb F$, the rank function of $\mathcal{Z}_3(G)$ can be extended to the rank function of an $\mathbb F$-representable matroid. In the
Philip S. Chodrow
We study the expected adjacency matrix of a uniformly random multigraph with fixed degree sequence $\mathbf{d} \in \mathbb{Z}_+^n$. This matrix arises in a variety of analyses of networked data sets, including modularity-maximization and mean-field theories of spreading processes. Its structure is well-understood for large, sparse, simple graphs: the expecte
Aishan Liu, Xianglong Liu, Chongzhi Zhang, Hang Yu
In practice, deep neural networks have been found to be vulnerable to various types of noise, such as adversarial examples and corruption. Various adversarial defense methods have accordingly been developed to improve adversarial robustness for deep models. However, simply training on data mixed with adversarial examples, most of these models still fail to d
Seokjin Bae, Hyunsoo Kim, Yun Suk Eo, Sheng Ran
A chiral superconductor has been proposed as one pathway to realize topological quantum computation utilizing the predicted Majorana normal fluid at its boundary (i.e., a point, edge, or surface). The search for experimental realizations has led to the discovery of 1D chiral superconducting systems. However, the long-sought 2D and 3D chiral superconductors w
Christian Elbracht, Jay Lilian Kneip, Maximilian Teegen
We prove canonical and non-canonical tree-of-tangles theorems for abstract separation systems that are merely structurally submodular. Our results imply all known tree-of-tangles theorems for graphs, matroids and abstract separation systems with submodular order functions, with greatly simplified and shortened proofs.
Jeremy Lacomis, Pengcheng Yin, Edward J. Schwartz, Miltiadis Allamanis
The decompiler is one of the most common tools for examining binaries without corresponding source code. It transforms binaries into high-level code, reversing the compilation process. Decompilers can reconstruct much of the information that is lost during the compilation process (e.g., structure and type information). Unfortunately, they do not reconstruct
Mohamed M. Anber, Erich Poppitz
We consider the most general fractional background fluxes in the color, flavor, and baryon number directions, compatible with the faithful action of the global symmetry of a given theory. We call the obstruction to gauging symmetries revealed by such backgrounds the baryon-color-flavor (BCF) 't Hooft anomaly. We apply the BCF anomaly to vector-like theories,
Sumiyoshi Abe
The concept of weak invariants has recently been introduced in the context of conserved quantities in finite-time processes in nonequilibrium quantum thermodynamics. A weak invariant itself has a time-dependent spectrum, but its expectation value remains constant under time evolution defined by a relevant master equation. Although its expectation value is th
Impact of the Hall effect in star formation : improving the angular momentum conservation
astro-ph.SRPierre Marchand, Kengo Tomida, Benoît Commerçon, Gilles Chabrier
We present here a minor modification of our numerical implementation of the Hall effect for the 2D Riemann solver used in Constrained Transport schemes, as described in Marchand et al. (2018). In the previous work, the tests showed that the angular momentum was not conserved during protostellar collapse simulations, with significant impact. By removing the w