April 2019 arXiv papers — page 72
Showing 7,101–7,200 of 12,989 papers
Ben Blum-Smith
We exhibit a family of real rotation groups whose subspace arrangements are not contained in that of any real reflection group, answering a question of Martino and Singh.
John Adler, Mikerah Quintyne-Collins
Increasing the transactional throughput of decentralized blockchains in a secure manner has been the holy grail of blockchain research for most of the past decade. This paper introduces a scheme for scaling blockchains while retaining virtually identical security and decentralization, colloquially known as optimistic rollup. We propose a layer-2 scaling tech
Quantitative characterization of short-range orthorhombic fluctuations in FeSe through pair distribution function analysis
cond-mat.supr-conBenjamin A. Frandsen, Qisi Wang, Shan Wu, Jun Zhao
Neutron and x-ray total scattering measurements have been performed on powder samples of the iron chalcogenide superconductor FeSe. Using pair distribution function (PDF) analysis of the total scattering data to investigate short-range atomic correlations, we establish the existence of an instantaneous, local orthorhombic structural distortion attributable t
Vahid Askarpour, Jesse Maassen
In this study, we calculate the $T$=300 K scattering and thermoelectric transport properties of rhombohedral GeTe using first-principles modeling. The room-temperature phase of GeTe has a layered structure, with cross-plane and in-plane directions oriented parallel and perpendicular to [111], respectively. Based on rigorous electron-phonon scattering, our tr
Kevin Wagner, Dániel Apai, Kaitlin M. Kratter
A major outstanding question regarding the formation of planetary systems is whether wide-orbit giant planets form differently than close-in giant planets. We aim to establish constraints on two key parameters that are relevant for understanding the formation of wide-orbit planets: 1) the relative mass function and 2) the fraction of systems hosting multiple
Monika Roznere, Alberto Quattrini Li
Recently, a new underwater imaging formation model presented that the coefficients related to the direct and backscatter transmission signals are dependent on the type of water, camera specifications, water depth, and imaging range. This paper proposes an underwater color correction method that integrates this new model on an underwater robot, using informat
Increases of a Diamagnetic Property by Flux-Pinning in Volume Defect-Dominating Superconductors
physics.app-phH. B. Lee, G. C. Kim, Y. C. Kim, R. K. Ko
Whereas there are two critical fields that are H$_{c1}$ and H$_{c2}$ in the ideal type II superconductor, there is another critical field H$_{c1}'$ defined as the field showing the maximum diamagnetic property in the real type II superconductor. We would present that H$_{c1}'$ is able to be proved theoretically and experimentally. We have derived an
Rodrigo G. Pereira, Francesco Buccheri, Alessandro De Martino, Reinhold Egger
We present an analytical low-energy theory of piezoelectric electron-phonon interactions in undoped Weyl semimetals, taking into account also Coulomb interactions. We show that piezoelectric interactions generate a long-range attractive potential between Weyl fermions. This potential comes with a characteristic angular anisotropy. From the one-loop renormali
Invariant subspaces of generalized Hardy algebras associated with compact abelian group actions on W*-algebras
math.OACostel Peligrad
We consider an action of a compact group whose dual is archimedean linearly ordered or a direct product (or sum) of such groups on a von Neumann algebra, M. We define the generalized Hardy subspace of the Hilbert space of a standard representation the algebra, and the Hardy subalgebra of analytic elements of M with respect to the action. We find conditions i
Elizabeth Paul, Ian Abel, Matt Landreman, William Dorland
Stellarators are a promising route to steady-state fusion power. However, to achieve the required confinement, the magnetic geometry must be highly optimized. This optimization requires navigating high-dimensional spaces, often necessitating the use of gradient-based methods. The gradient of the neoclassical fluxes is expensive to compute with classical meth
Isomorph invariance and thermodynamics of repulsive dense bi-Yukawa one-component plasmas
physics.plasm-phF. Lucco Castello, P. Tolias, J. S. Hansen, J. C. Dyre
In numerous realizations of complex plasmas, dust-dust interactions are characterized by two screening lengths and are thus better described by a combination of Yukawa potentials. The present work investigates the static correlations and the thermodynamics of repulsive dense bi-Yukawa fluids based on the fact that such strongly coupled systems exhibit isomor
Wide band enhancement of the transverse magneto-optical Kerr effect in magnetite-based plasmonic crystals
physics.opticsS. A. Dyakov, L. Klompmaker, F. Spitzer, I. M. Fradkin
The transverse magneto-optical Kerr effect (TMOKE) in magnetite-based magneto-plasmonic crystals is studied experimentally and theoretically. We analyze angle-resolved TMOKE spectra from two types of structures where noble metallic stripes are incorporated inside a thin magnetite film or located on top of a homogeneous film. A multiple wide band enhancement
Martian cloud climatology and life cycle extracted from Mars Express OMEGA spectral images
astro-ph.EPAndré Szantai, Joachim Audouard, Francois Forget, Kevin S. Olsen
We extracted a Martian water-ice cloud climatology from OMEGA data covering 7 Martian years (MY 26-32). We derived two products, the Reversed Ice Cloud Index (ICIR) and the Percentage of Cloudy Pixels (PCP), indicating the mean cloud thickness and nebulosity over a regular grid (1° longitude x 1° latitude x 1° Ls x 1 h Local Time). The ICIR has been shown to
A Search for Cosmic Neutrino and Gamma-Ray Emitting Transients in 7.3 Years of ANTARES and Fermi LAT Data
astro-ph.HEH. A. Ayala Solares, D. F. Cowen, J. J. DeLaunay, D. B. Fox
We analyze 7.3 years of ANTARES high-energy neutrino and Fermi LAT γ-ray data in search of cosmic neutrino + γ-ray (ν+γ) transient sources or source populations. Our analysis has the potential to detect either individual ν+γ transient sources (durations δt < 1000~s), if they exhibit sufficient γ-ray or neutrino multiplicity, or a statistical excess of ν+γ tr
Michael Levine, Donald Richards, Jianxi Su
Truncated multivariate distributions arise extensively in econometric modelling when non-negative random variables are intrinsic to the data-generation process. More broadly, truncated multivariate distributions have appeared in censored and truncated regression models, simultaneous equations modelling, multivariate regression, and applications going back to
Yuxin Hou, Juho Kannala, Arno Solin
We propose a novel idea for depth estimation from multi-view image-pose pairs, where the model has capability to leverage information from previous latent-space encodings of the scene. This model uses pairs of images and poses, which are passed through an encoder--decoder model for disparity estimation. The novelty lies in soft-constraining the bottleneck la
Bas Lemmens, Hent van Imhoff, Onno van Gaans
A basic problem in the theory of partially ordered vector spaces is to characterise those cones on which every order-isomorphism is linear. We show that this is the case for every Archimedean cone that equals the inf-sup hull of the sum of its engaged extreme rays. This condition is milder than existing ones and is satisfied by, for example, the cone of posi
Approximation of tensor fields on surfaces of arbitrary topology based on local Monge parametrizations
physics.comp-phAlejandro Torres-Sánchez, Daniel Santos-Oliván, Marino Arroyo
We introduce a new method, the Local Monge Parametrizations (LMP) method, to approximate tensor fields on general surfaces given by a collection of local parametrizations, e.g.~as in finite element or NURBS surface representations. Our goal is to use this method to solve numerically tensor-valued partial differential equations (PDE) on surfaces. Previous met
Z. Varga, R. Vertesi, G. G. Barnafoldi
A study investigating a possible jet shape dependence on the charged event multiplicity was performed on collision samples generated by Monte-Carlo (MC) event generators PYTHIA and HIJING++. We calculated the integral jet shape and found a significant modification caused by multiple-parton interactions. By interchanging and enabling different model ingredien
Extrapolating Beyond Suboptimal Demonstrations via Inverse Reinforcement Learning from Observations
cs.LGDaniel S. Brown, Wonjoon Goo, Prabhat Nagarajan, Scott Niekum
A critical flaw of existing inverse reinforcement learning (IRL) methods is their inability to significantly outperform the demonstrator. This is because IRL typically seeks a reward function that makes the demonstrator appear near-optimal, rather than inferring the underlying intentions of the demonstrator that may have been poorly executed in practice. In
Barak Shoshany
In a recent paper, we introduced a new discretization scheme for gravity in 2+1 dimensions. Starting from the continuum theory, this new scheme allowed us to rigorously obtain the discrete phase space of loop gravity, coupled to particle-like "edge mode" degrees of freedom. In this work, we expand on that result by considering the most general choice
Jiexin Duan, Michael Levine, Junxiang Luo, Yongming Qu
In this manuscript, we investigate the concept of the mean response for a treatment group mean as well as its estimation and prediction for generalized linear models with a subject-wise random effect. Generalized linear models are commonly used to analyze categorical data. The model-based mean for a treatment group usually estimates the response at the mean
I. R. Passos, G. A. P. Ribeiro
We consider the six-vertex model with reflecting end boundary condition. We compute analytically boundary correlation functions, such as the boundary polarization and the emptiness formation probability. In order to do that, we use the Sklyanin's reflection algebra to derive recursion relations for the partition function of the model as well as for the b
Jun Guo, Saeed Karimi-Bidhendi, Hamid Jafarkhani
We study a wireless ad-hoc sensor network (WASN) where $N$ sensors gather data from the surrounding environment and transmit their sensed information to $M$ fusion centers (FCs) via multi-hop wireless communications. This node deployment problem is formulated as an optimization problem to make a trade-off between the sensing uncertainty and energy consumptio
Francisco M. Fernández
In this paper we analyze a recently proposed approach for the construction of antisymmetric functions for atomic and molecular systems. It is based on the assumption that the main problems with Hartree-Fock wavefunctions stem from their lack of proper permutation symmetry. This alternative building approach is based on products of a space times a spin functi
Chronic stress may disrupt covariant fluctuations of vitamin D and cortisol plasma levels in pregnant sheep during the last trimester: a preliminary report
q-bio.TOColin Wakefield, Ben Janoschek, Yael Frank, Floyd Karp
Psychosocial stress during pregnancy is a known contributor to preterm birth, but also has been increasingly appreciated as an in utero insult acting long-term on prenatal and postnatal neurodevelopmental trajectories. These events impact many information molecules, including both vitamin D and cortisol. Both have been linked to low birth premature babies. C
Angana Ray, Rosa Di Felice
Genome editing allows scientists to change an organism's DNA. One promising genome editing protocol, already validated in living organisms, is based on clustered regularly interspaced short palindromic repeats (CRISPR)/Cas protein-nucleic acid complexes. When the CRISPR/Cas approach was first demonstrated in 2012, its advantages with respect to previousl
Resolving the extended stellar atmospheres of Asymptotic Giant Branch stars at (sub-)millimetre wavelengths
astro-ph.SRW. H. T. Vlemmings, T. Khouri, H. Olofsson
The initial conditions for the mass loss during the asymptotic giant branch (AGB) phase are set in their extended atmospheres, where, among others, convection and pulsation driven shocks determine the physical conditions. High resolution observations of AGB stars at (sub)millimetre wavelengths can now directly determine the morphology, activity, density, and
Kean Chen, Jianguo Li, Weiyao Lin, John See
One-stage object detectors are trained by optimizing classification-loss and localization-loss simultaneously, with the former suffering much from extreme foreground-background class imbalance issue due to the large number of anchors. This paper alleviates this issue by proposing a novel framework to replace the classification task in one-stage detectors wit
R. G. Polozkov, N. Y. Senkevich, S. Morina, P. Kuzhir
We use an ab-initio approach to design and study a novel two-dimensional material - a planar array of carbon nanotubes separated by an optimal distance defined by the van der Waals interaction. We show that the energy spectrum for an array of quasi-metallic nanotubes is described by a strongly anisotropic hyperbolic dispersion and formulate a model low-energ
Complementarity of Stacking and Multiplet Constraints on the Blazar Contribution to the Cumulative High-Energy Neutrino Intensity
astro-ph.HEChengchao Yuan, Kohta Murase, Peter Mészáros
We investigate the blazar contribution to the cumulative neutrino intensity assuming a generic relationship between neutrino and gamma-ray luminosities, $L_ν\propto (L_{\rm ph})^{γ_{\rm lw}}$. Using the gamma-ray luminosity functions for blazars including flat spectrum radio quasars (FSRQs) and BL Lac objects, as well as the $Fermi$-LAT detection efficiency,
B. Ramakrishnan, Lalit Vaishya
In \cite{ono}, K. Ono, S. Robins and P.T. Wahl considered the problem of determining formulas for the number of representations of a natural number $n$ by a sum of $k$ triangular numbers and derived many applications, including the one connecting these numbers with the number of representations of $n$ as a sum of $k$ odd square integers. They also obtained a
Melody Chan, Carel Faber, Soren Galatius, Sam Payne
We prove a formula, conjectured by Zagier, for the $S_n$-equivariant Euler characteristic of the top weight cohomology of $M_{g,n}$.
Nikolas Andreou, Nicola Franchini, Giulia Ventagli, Thomas P. Sotiriou
Spontaneous scalarization is a mechanism that endows relativistic stars and black holes with a nontrivial configuration only when their spacetime curvature exceeds some threshold. The standard way to trigger spontaneous scalarization is via a tachyonic instability at the linear level, which is eventually quenched due to the effect of non-linear terms. In thi
Inversion-protected higher order topological superconductivity in monolayer WTe$_2$
cond-mat.supr-conYi-Ting Hsu, William S. Cole, Rui-Xing Zhang, Jay D. Sau
Monolayer WTe$_2$, a centrosymmetric transition metal dichacogenide, has recently been established as a quantum spin Hall insulator and found superconducting upon gating. Here we study the pairing symmetry and topological nature of superconducting WTe$_2$ with a microscopic model at mean-field level. Surprisingly, we find that the spin-triplet phases in our
Jonathan M. Cullen, Benjamin D. Pecjak, Darren J. Scott
We calculate the full set of next-to-leading order (NLO) corrections to $h\to b\bar{b}$ decay in the dimension-6 Standard Model Effective Field Theory (SMEFT). Our calculation forms the basis for precision studies of this decay mode in effective field theory, providing analytic and numerical results for contributions of the 45 dimension-6 operators appearing
Tyler Holland-Ashford, Laura A. Lopez, Katie Auchettl
Supernova remnants (SNRs) offer the means to study supernovae (SNe) long after the original explosion and can provide a unique insight into the mechanism that governs these energetic events. In this work, we examine the morphologies of X-ray emission from different elements found in the youngest known core-collapse (CC) SNR in the Milky Way, Cassiopeia A. Th
Shihong Liao, Liang Gao, Carlos S. Frenk, Robert J. J. Grand
We investigate the formation of ultra-diffuse galaxies (UDGs) using the Auriga high-resolution cosmological magneto-hydrodynamical simulations of Milky Way-sized galaxies. We identify a sample of $92$ UDGs in the simulations that match a wide range of observables such as sizes, central surface brightness, Sérsic indices, colors, spatial distribution and abun
Topological Phase Transition driven by Infinitesimal Instability: Majorana Fermions in Non-Hermitian Spintronics
cond-mat.mes-hallNobuyuki Okuma, Masatoshi Sato
Quantum phase transitions are intriguing and fundamental cooperative phenomena in physics. Analyzing a superconducting nanowire with spin-dependent non-Hermitian hopping, we discover a topological quantum phase transition driven by infinitesimal cascade instability. The anomalous phase transition is complementary to the universal non-Bloch wave behavior of n
Kyle Kremer, Wenbin Lu, Carl L. Rodriguez, Mitchell Lachat
In a dense stellar environment, such as the core of a globular cluster (GC), dynamical interactions with black holes (BHs) are expected to lead to a variety of astrophysical transients. Here we explore tidal disruption events (TDEs) of stars by stellar-mass BHs through collisions and close encounters. Using state-of-the-art $N$-body simulations, we show that
Forming Pop III binaries in self-gravitating disks: how to keep the orbital angular momentum
astro-ph.GASunmyon Chon, Takashi Hosokawa
The disk fragmentation is a possible process leading to the formation of Population III stellar binary systems. However, numerical simulations show diverse fates of the fragments; some evolve into stable binaries and others merge away with a central star. To clarify the physics behind such diversity, we perform a series of three dimensional hydrodynamics sim
Anand Bhattad, Min Jin Chong, Kaizhao Liang, Bo Li
Machine learning models, especially deep neural networks (DNNs), have been shown to be vulnerable against adversarial examples which are carefully crafted samples with a small magnitude of the perturbation. Such adversarial perturbations are usually restricted by bounding their $\mathcal{L}_p$ norm such that they are imperceptible, and thus many current defe
Yuyin Zhou, Zhe Li, Song Bai, Chong Wang
Accurate multi-organ abdominal CT segmentation is essential to many clinical applications such as computer-aided intervention. As data annotation requires massive human labor from experienced radiologists, it is common that training data are partially labeled, e.g., pancreas datasets only have the pancreas labeled while leaving the rest marked as background.
Adrian Bulat, Jean Kossaifi, Georgios Tzimiropoulos, Maja Pantic
The prominence of deep learning, large amount of annotated data and increasingly powerful hardware made it possible to reach remarkable performance for supervised classification tasks, in many cases saturating the training sets. However the resulting models are specialized to a single very specific task and domain. Adapting the learned classification to new
Seung-Joo Lee, Wolfgang Lerche, Timo Weigand
We systematically analyse weak coupling limits for 2-form tensor fields in the presence of gravity. Such limits are significant for testing various versions of the Weak Gravity and Swampland Distance Conjectures, and more broadly, the phenomenon of emergence. The weak coupling limits for 2-forms correspond to certain infinite-distance limits in the moduli sp
Pasquale Bosso, Octavio Obregón
A Kantowski-Sachs model with a modified quantization prescription is considered. Such quantization rules, inspired by the so-called Generalized Uncertainty Principle (GUP), correspond to a modified commutation relation between minisuperspace variables and their conjugate momenta. For a wide range of the modification parameter, this approach differentiates fr
Igor Konnov
We suggest a conjugate subgradient type method without any line-search for minimization of convex non differentiable functions. Unlike the custom methods of this class, it does not require monotone decrease of the goal function and reduces the implementation cost of each iteration essentially. At the same time, its step-size procedure takes into account beha
A Composite Likelihood-based Approach for Change-point Detection in Spatio-temporal Processes
stat.MEZifeng Zhao, Ting Fung Ma, Wai Leong Ng, Chun Yip Yau
This paper develops a unified and computationally efficient method for change-point estimation along the time dimension in a non-stationary spatio-temporal process. By modeling a non-stationary spatio-temporal process as a piecewise stationary spatio-temporal process, we consider simultaneous estimation of the number and locations of change-points, and model
$\mathcal N=2$ Supersymmetry Deformations, Electromagnetic Duality and Dirac-Born-Infeld Actions
hep-thIgnatios Antoniadis, Hongliang Jiang, Osmin Lacombe
We study the general deformation of $\mathcal N=2$ supersymmetry transformations of a vector multiplet that forms a (constant) triplet under the $SU(2)$ R-symmetry corresponding to the magnetic dual of the triplet of the Fayet-Iliopoulos (FI) parameters. We show that in the presence of both triplets, the induced scalar potential of a vector multiplet with ge
Janos Polonyi, Ines Rachid
The master equation for the reduced density matrix of a charged particle interacting with a translation invariant weakly coupled environment is considered. The electric current is renormalized by the system-environment interaction, leading to a direct signature of the environment in the bremsstrahlung. The general solution is given in the absence of the exte
Arvind Shrivats, Sebastian Jaimungal
SREC markets are a relatively novel market-based system to incentivize the production of energy from solar means. A regulator imposes a floor on the amount of energy each regulated firm must generate from solar power in a given period and provides them with certificates for each generated MWh. Firms offset these certificates against the floor and pay a penal
Improved results for sending-or-not-sending twin-field quantun key distribution: breaking the absolute limit of repeaterless key rate
quant-phHai Xu, Zong-Wen Yu, Cong Jiang, Xiao-Long Hu
We present improved method of sending-or-not-sending twin-field quantum key distribution (SNS TF-QKD) based on its structure and the application of error rejection. %And we present iteration formula for bit-flip error rate of the survived bits after error rejection. Taking the finite key effect into consideration with only $10^{11}$ total pulses, we show tha
Sheng-Yong Niu, Lun-Zhang Guo, Yue Li, Tzung-Dau Wang
As the rapid growth of high-speed and deep-tissue imaging in biomedical research, it is urgent to find a robust and effective denoising method to retain morphological features for further texture analysis and segmentation. Conventional denoising filters and models can easily suppress perturbative noises in high contrast images. However, for low photon budget
Characterizing the sensitivity of isolated continuous gravitational wave searches to binary orbits
gr-qcAvneet Singh, Maria Alessandra Papa, Vladimir Dergachev
Broadband all-sky searches for continuous gravitational waves (CW) from isolated neutron stars typically yield a number of significant candidates that are discarded through hierarchical semi-coherent and coherent follow-up searches. However, these searches target purely isolated sources and do not take into account possible phase modulations to the signals d
Ahmad Kamandi, Keyvan Amini
In this paper, a new conjugate gradient-like algorithm is proposed to solve unconstrained optimization problems. The step directions generated by the new algorithm satisfy sufficient descent condition independent of the line search. The global convergence of the new algorithm, with the Armijo backtracking line search, is proved. Numerical experiments indicat
Kesha Hietala, Robert Rand, Shih-Han Hung, Xiaodi Wu
We present sqire, a low-level language for quantum computing and verification. sqire uses a global register of quantum bits, allowing easy compilation to and from existing `quantum assembly' languages and simplifying the verification process. We demonstrate the power of sqire as an intermediate representation of quantum programs by verifying a number of
David Edward Bruschi
We study the time evolution of two coupled quantum harmonic oscillators interacting through nonlinear optomechanical-like Hamiltonians that include cross-Kerr interactions. We employ techniques developed to decouple the time-evolution operator and obtain the analytical solution for the time evolution of the system. We apply these results to obtain explicit e
Tom Silver, Kelsey R. Allen, Alex K. Lew, Leslie Pack Kaelbling
Humans can learn many novel tasks from a very small number (1--5) of demonstrations, in stark contrast to the data requirements of nearly tabula rasa deep learning methods. We propose an expressive class of policies, a strong but general prior, and a learning algorithm that, together, can learn interesting policies from very few examples. We represent polici
Clément Elvira, Rémi Gribonval, Charles Soussen, Cédric Herzet
This paper presents new theoretical results on sparse recovery guarantees for a greedy algorithm, Orthogonal Matching Pursuit (OMP), in the context of continuous parametric dictionaries. Here, the continuous setting means that the dictionary is made up of an infinite uncountable number of atoms. In this work, we rely on the Hilbert structure of the observati
Menno H. Schellekens, Floris Holstege, Taha Yasseri
Different kinds of "gender gap" have been reported in different walks of the scientific life, almost always favouring male scientists over females. In this work, for the first time, we present a large-scale empirical analysis to ask whether female scientists with the same level of scientific accomplishment are as likely as males to be recognised. We
Yuanhao Wang, Jiachen Hu, Xiaoyu Chen, Liwei Wang
We study the problem of regret minimization for distributed bandits learning, in which $M$ agents work collaboratively to minimize their total regret under the coordination of a central server. Our goal is to design communication protocols with near-optimal regret and little communication cost, which is measured by the total amount of transmitted data. For d
Functionals defined on piecewise rigid functions: Integral representation and $Γ$-convergence
math.APManuel Friedrich, Francesco Solombrino
We analyze integral representation and $Γ$-convergence properties of functionals defined on \emph{piecewise rigid functions}, i.e., functions which are piecewise affine on a Caccioppoli partition where the derivative in each component is constant and lies in a set without rank-one connections. Such functionals account for interfacial energies in the variatio
Shi Pi, Misao Sasaki, Ying-li Zhang
We study the primordial tensor perturbation produced from the double inflationary scenario with an intermediate break stage. Because of the transitions, the power spectrum deviates from the vacuum one and there will appear oscillatory behavior. In the case of a scalar-type curvature perturbation, it is known that the amplitude of these oscillations may be en
M. Angeli, E. Tosatti, M. Fabrizio
The surprising insulating and superconducting states of narrow-band graphene twisted bilayers have been mostly discussed so far in terms of strong electron correlation, with little or no attention to phonons and electron-phonon effects. We found that, among the 33492 phonons of a fully relaxed $θ=1.08^\circ$ twisted bilayer, there are few special, hard and n
Anthony Iarrobino, Chris McDaniel, Alexandra Seceleanu
A connected sum construction for local rings was introduced in a paper by H. Ananthnarayan, L. Avramov, and W.F. Moore. In the graded Artinian Gorenstein case, this can be viewed as an algebraic analogue of the topological construction of the same name. We give two alternative description of this algebraic connected sum: the first uses algebraic analogues of
Mihailo Čubrović
We perform a systematic study of the maximum Lyapunov exponent values $λ$ for the motion of classical closed strings in Anti-de Sitter black hole geometries with spherical, planar and hyperbolic horizons. Analytical estimates from the linearized variational equations together with numerical integrations predict the bulk Lyapunov exponent value as $λ\approx 2
Rubén Arjona, Wilmar Cardona, Savvas Nesseris
We present a family of designer Horndeski models, i.e. models that have a background exactly equal to that of the $Λ$CDM model but perturbations given by the Horndeski theory. Then, we extend the effective fluid approach to Horndeski theories, providing simple analytic formulae for the equivalent dark energy effective fluid pressure, density and velocity. We
Michael Cary
In this paper we prove that the dominator chromatic number of every oriented tree is invariant under reversal of orientation. In addition to this marquee result, we also prove the exact dominator chromatic number for arborescences and anti-arborescences as well as bounds on other orientations of oft studied tree topologies including generalized stars and cat
Adversarial Learning in Statistical Classification: A Comprehensive Review of Defenses Against Attacks
cs.LGDavid J. Miller, Zhen Xiang, George Kesidis
There is great potential for damage from adversarial learning (AL) attacks on machine-learning based systems. In this paper, we provide a contemporary survey of AL, focused particularly on defenses against attacks on statistical classifiers. After introducing relevant terminology and the goals and range of possible knowledge of both attackers and defenders,
Wei-Chen Lin, Michael J. P. Morse, William H. Kinney
There has been considerable recent interest in a new class of non-slow roll inflationary solutions known as \textit{constant roll} inflation. Constant roll solutions are a generalization of the ultra-slow roll (USR) solution, where the first Hubble slow roll parameter $ε$ is small, but the second Hubble slow roll parameter $η$ is not. While it is known that
Outlier-robust estimation of a sparse linear model using $\ell_1$-penalized Huber's $M$-estimator
math.STArnak S. Dalalyan, Philip Thompson
We study the problem of estimating a $p$-dimensional $s$-sparse vector in a linear model with Gaussian design and additive noise. In the case where the labels are contaminated by at most $o$ adversarial outliers, we prove that the $\ell_1$-penalized Huber's $M$-estimator based on $n$ samples attains the optimal rate of convergence $(s/n)^{1/2} + (o/n)$,
Piotr Bania
An information based method for solving stochastic control problems with partial observation has been proposed. First, the information-theoretic lower bounds of the cost function has been analysed. It has been shown, under rather weak assumptions, that reduction of the expected cost with closed-loop control compared to the best open-loop strategy is upper bo
Malihe Alikhani, Sreyasi Nag Chowdhury, Gerard de Melo, Matthew Stone
This paper presents a novel crowd-sourced resource for multimodal discourse: our resource characterizes inferences in image-text contexts in the domain of cooking recipes in the form of coherence relations. Like previous corpora annotating discourse structure between text arguments, such as the Penn Discourse Treebank, our new corpus aids in establishing a b
Aatifa Bargach, Farida Bargach, Ahmed Errahmani, Taoufik Ouali
We investigate observational constraints on inflationary parameters in the context of an holographic cosmology with an induced gravity correction. We consider two situations where a universe is firstly filled with a scalar field and secondly with a tachyon field. Both cases are investigated in a slow-roll regime. We adopt a quadratic potential and an exponen
Verified partial eigenvalue computations using contour integrals for Hermitian generalized eigenproblems
math.NAAkira Imakura, Keiichi Morikuni, Akitoshi Takayasu
We propose a verified computation method for partial eigenvalues of a Hermitian generalized eigenproblem. The block Sakurai-Sugiura Hankel method, a contour integral-type eigensolver, can reduce a given eigenproblem into a generalized eigenproblem of block Hankel matrices whose entries consist of complex moments. In this study, we evaluate all errors in comp
Blind search for complex chemical pathways using Harmonic Linear Discriminant Analysis
physics.chem-phValerio Rizzi, Dan Mendels, Emilia Sicilia, Michele Parrinello
Disentangling the mechanistic details of a chemical reaction pathway is a hard problem that often requires a considerable amount of chemical intuition and a component of luck. Experiments struggle in observing short-life metastable intermediates, while computer simulations often rely upon a good initial guess. In this work, we propose a method that, from the
Sara Turcotte, Samuel Boutin, Julien Camirand Lemyre, Ion Garate
Solid-state experimental realizations of Majorana bound states are based on materials with strong intrinsic spin-orbit interactions. In this paper, we explore an alternative approach where spin-orbit coupling is induced artificially through a nonuniform magnetic field that originates from an array of micromagnets. Using a recently developed optimization algo
Coherent J/$ψ$ photoproduction at forward rapidity in ultra-peripheral Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=5.02$ TeV
nucl-exALICE Collaboration
The ALICE collaboration performed the first rapidity-differential measurement of coherent J/$ψ$ photoproduction in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. The J/$ψ$ is detected via its dimuon decay in the forward rapidity region ($-4.0 < y < -2.5$) for events where the hadronic activity is required to be
Aram Karakhanyan
We study the probability measures $ρ\in \mathcal M(\mathbb R^2)$ minimizing the functional \[ J[ρ]=\iint \log\frac1{|x-y|}dρ(x)dρ(y)+d^2(ρ, ρ_0), \] where $ρ_0$ is a given probability measure and $d(ρ, ρ_0)$ is the 2-Wasserstein distance of $ρ$ and $ρ_0$. % We prove the existence of minimizers $ρ$ and show that the potential $U^ρ=-\log|x|\ast ρ$ solves a deg
Francesco Tonolini, Jack Radford, Alex Turpin, Daniele Faccio
Machine learning methods for computational imaging require uncertainty estimation to be reliable in real settings. While Bayesian models offer a computationally tractable way of recovering uncertainty, they need large data volumes to be trained, which in imaging applications implicates prohibitively expensive collections with specific imaging instruments. Th
Similarities between policy gradient methods (PGM) in Reinforcement learning (RL) and supervised learning (SL)
cs.LGEric Benhamou
Reinforcement learning (RL) is about sequential decision making and is traditionally opposed to supervised learning (SL) and unsupervised learning (USL). In RL, given the current state, the agent makes a decision that may influence the next state as opposed to SL (and USL) where, the next state remains the same, regardless of the decisions taken, either in b
Multi-Armed Bandit for Energy-Efficient and Delay-Sensitive Edge Computing in Dynamic Networks with Uncertainty
cs.LGSaeed Ghoorchian, Setareh Maghsudi
In the edge computing paradigm, mobile devices offload the computational tasks to an edge server by routing the required data over the wireless network. The full potential of edge computing becomes realized only if a smart device selects the most appropriate server in terms of the latency and energy consumption, among many available ones. The server selectio
Valentina Apollonio, Roberto D'Autilia, Benedetto Scoppola, Elisabetta Scoppola
We define a class of Markovian parallel dynamics for spin systems on arbitrary graphs with nearest neighbor interaction described by a Hamiltonian function $H(\sigma)$. These dynamics turn out to be reversible and their stationary measure is explicitly determined. Convergence to equilibrium and relation of the stationary measure to the usual Gibbs measure ar
Jiaqi Guan, Ye Yuan, Kris M. Kitani, Nicholas Rhinehart
Automatically reasoning about future human behaviors is a difficult problem but has significant practical applications to assistive systems. Part of this difficulty stems from learning systems' inability to represent all kinds of behaviors. Some behaviors, such as motion, are best described with continuous representations, whereas others, such as picking
Towards mapping turbulence in the intra-cluster medium -- II. Measurement uncertainties in the estimation of structure functions
astro-ph.COE. Cucchetti, N. Clerc, E. Pointecouteau, P. Peille
X-ray observations of the hot gas filling the intra-cluster medium provide a wealth of information on the dynamics of clusters of galaxies. The global equilibrium of the ICM is believed to be partially ensured by non-thermal pressure support, notably the dissipation of energy through turbulent motions. Accurate mapping of turbulence using X-ray emission line
Towards mapping turbulence in the intra-cluster medium -- I. Sample variance in spatially-resolved X-ray line diagnostics
astro-ph.CON. Clerc, E. Cucchetti, E. Pointecouteau, P. Peille
X-ray observations of galaxy clusters provide insights on the nature of gaseous turbulent motions, their physical scales and on the fundamental processes they are related to. Spatially-resolved, high-resolution spectral measurements of X-ray emission lines provide diagnostics on the nature of turbulent motions in emitting atmospheres. Since they are acting o
Lucas Hackl, Robert H. Jonsson
We compute the minimal energy cost for extracting entanglement from the ground state of a bosonic or fermionic quadratic system. Specifically, we find the minimal energy increase $ΔE_{\mathrm{min}}$ in the system resulting from replacing an entangled pair of modes, sharing entanglement entropy $ΔS$, by a product state, and we show how to construct modes achi
Amir Shpilka
We prove Sylvester-Gallai type theorems for quadratic polynomials. Specifically, we prove that if a finite collection $\mathcal Q$, of irreducible polynomials of degree at most $2$, satisfy that for every two polynomials $Q_1,Q_2\in {\mathcal Q}$ there is a third polynomial $Q_3\in{\mathcal Q}$ so that whenever $Q_1$ and $Q_2$ vanish then also $Q_3$ vanishes
Abdallah Daddi-Moussa-Ider, Benno Liebchen, Andreas M. Menzel, Hartmut Löwen
With the rapid advent of biomedical and biotechnological innovations, a deep understanding of the nature of interaction between nanomaterials and cell membranes, tissues, and organs, has become increasingly important. Active penetration of nanoparticles through cell membranes is a fascinating phenomenon that may have important implications in various biomedi
The magnetic structure factor of correlated moments in small-angle neutron scattering
cond-mat.mes-hallDirk Honecker, Luis Fernández Barquín, Philipp Bender
The interplay between structural and magnetic properties of nanostructured magnetic materials allows to realize unconventional magnetic effects, which results in a demand for experimental techniques to determine the magnetization profile with nanoscale resolution. Magnetic small-angle neutron scattering (SANS) probes both the chemical and magnetic nanostruct
Sahar Mohajerani, Stephane Lafortune
We consider the verification of current-state and K-step opacity for systems modeled as interacting non-deterministic finite-state automata. We describe a new methodology for compositional opacity verification that employs abstraction, in the form of a notion called opaque observation equivalence, and that leverages existing compositional nonblocking verific
Salvatore Floccari
We study the Mumford--Tate conjecture for hyperk\"{a}hler varieties. We show that the full conjecture holds for all varieties deformation equivalent to either an Hilbert scheme of points on a K3 surface or to O'Grady's ten dimensional example, and all of their self-products. For an arbitrary hyperk\"{a}hler variety whose second Betti number is not 3, we prov
Density response of holographic metallic IR fixed points with translational pseudo-spontaneous symmetry breaking
hep-thAurelio Romero-Bermúdez
The density response of charged liquids contains a collective excitation known as the plasmon. In holographic systems with translational invariance the origin of this collective excitation is traced back to the presence of zero-sound. Using a holographic model in which translational symmetry is broken pseudo-spontaneously, we show the density response is not
Multimodal Machine Learning-based Knee Osteoarthritis Progression Prediction from Plain Radiographs and Clinical Data
cs.CVAleksei Tiulpin, Stefan Klein, Sita M. A. Bierma-Zeinstra, Jérôme Thevenot
Knee osteoarthritis (OA) is the most common musculoskeletal disease without a cure, and current treatment options are limited to symptomatic relief. Prediction of OA progression is a very challenging and timely issue, and it could, if resolved, accelerate the disease modifying drug development and ultimately help to prevent millions of total joint replacemen
Ohr Lahad, Ran Finkelstein, Omri Davidson, Ohad Michel
The resonant absorption of light by an ensemble of absorbers decreases when the resonance is inhomogeneously broadened, as only a fraction of the ensemble contributes to the absorption at any given optical frequency. Recovering the lost absorption cross-section is of great importance for various applications of light-matter interactions, particularly in quan
Amal Alphonse, Michael Hintermüller, Carlos N. Rautenberg
For a class of quasi-variational inequalities (QVIs) of obstacle-type the stability of its solution set and associated optimal control problems are considered. These optimal control problems are non-standard in the sense that they involve an objective with set-valued arguments. The approach to study the solution stability is based on perturbations of minimal
George T. Hall, Pietro S. Oliveto, Dirk Sudholt
Algorithm configurators are automated methods to optimise the parameters of an algorithm for a class of problems. We evaluate the performance of a simple random local search configurator (ParamRLS) for tuning the neighbourhood size $k$ of the RLS$_k$ algorithm. We measure performance as the expected number of configuration evaluations required to identify th
Efficient computation of permanents, with applications to boson sampling and random matrices
quant-phP. H. Lundow, K. Markström
In order to find the outcome probabilities of quantum mechanical systems like the optical networks underlying Boson sampling, it is necessary to be able to compute the permanents of unitary matrices, a computationally hard task. Here we first discuss how to compute the permanent efficiently on a parallel computer, followed by algorithms which provide an expo
Erik Sy, Christian Burkert, Tobias Mueller, Hannes Federrath
QUIC is a secure transport protocol that improves the performance of HTTPS. An initial QUIC handshake that enforces a strict validation of the client's source address requires two round-trips. In this work, we extend QUIC's address validation mechanism by an out-of-band validation token to save one round-trip time during the initial handshake. The pr
Fan Yang
Inclusion logic is a variant of dependence logic that was shown to have the same expressive power as positive greatest fixed-point logic. Inclusion logic is not axiomatizable in full, but its first-order consequences can be axiomatized. In this paper, we provide such an explicit partial axiomatization by introducing a system of natural deduction for inclusio