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Related papers: Discrete Directional Gabor Frames

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Given an Euclidean space, this paper elucidates the topological link between the partial derivatives of the Minkowski functional associated to a set (assumed to be compact, convex, with a differentiable boundary and a non-empty interior)…

Differential Geometry · Mathematics 2024-07-18 Gustave Bainier , Benoit Marx , Jean-Christophe Ponsart

We study sharp frame bounds of Gabor frames with the standard Gaussian window and prove that the square lattice optimizes both the lower and the upper frame bound among all rectangular lattices. This proves a conjecture of Floch, Alard &…

Functional Analysis · Mathematics 2016-10-05 Markus Faulhuber , Stefan Steinerberger

Redundancy is the qualitative property which makes Hilbert space frames so useful in practice. However, developing a meaningful quantitative notion of redundancy for infinite frames has proven elusive. Though quantitative candidates for…

Functional Analysis · Mathematics 2009-12-30 Radu Balan , Pete Casazza , Zeph Landau

We give a new and constructive proof of the existence of global-in-time weak solutions of the 3-dimensional incompressible semi-geostrophic equations (SG) in geostrophic coordinates, for arbitrary initial measures with compact support. This…

Analysis of PDEs · Mathematics 2022-01-19 David P. Bourne , Charlie P. Egan , Beatrice Pelloni , Mark Wilkinson

We study computational aspects of repulsive Gibbs point processes, which are probabilistic models of interacting particles in a finite-volume region of space. We introduce an approach for reducing a Gibbs point process to the hard-core…

Data Structures and Algorithms · Computer Science 2023-12-15 Tobias Friedrich , Andreas Göbel , Maximilian Katzmann , Martin Krejca , Marcus Pappik

We propose an efficient numerical method to study the transport properties of armchair graphene ribbons in the presence of a generic external potential. The method is based on a continuum envelope-function description with physical boundary…

Mesoscale and Nanoscale Physics · Physics 2014-07-07 Demetrio Logoteta , Paolo Marconcini , Claudio Bonati , Maurizio Fagotti , Massimo Macucci

This paper extends sliding-mode control theory to nonlinear systems evolving on smooth manifolds. Building on differential geometric methods, we reformulate Filippov's notion of solutions, characterize well-defined vector fields on quotient…

Optimization and Control · Mathematics 2025-09-17 Fernando Castaños

We consider the simulation of barotropic flow of gas in long pipes and pipe networks. Based on a Hamiltonian reformulation of the governing system, a fully discrete approximation scheme is proposed using mixed finite elements in space and…

Numerical Analysis · Mathematics 2023-03-01 H. Egger , J. Giesselmann , T. Kunkel , N. Philippi

In this paper we develop some combinatorial models for continuous spaces. In this spirit we study the approximations of continuous spaces by graphs, molecular spaces and coordinate matrices. We define the dimension on a discrete space by…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Alexander V. Evako

Discrete-Gauss states are a new class of gaussian solutions of the free Schr\"odinger equation owning discrete rotational symmetry. They are obtained by acting with a discrete deformation operator onto Laguerre-Gauss modes. We present a…

Optics · Physics 2014-09-05 Albert Ferrando

We consider the non-equilibrium orbital dynamics of spin-polarized ultracold fermions in the first excited band of an optical lattice. A specific lattice depth and filling configuration is designed to allow the $p_x$ and $p_y$ excited…

We apply the orthonormalization procedure previously introduced by two of us and adopted in connection with coherent states to Gabor frames and other examples. For instance, for Gabor frames we show how to construct $g(x)\in L^2(\Bbb{R})$…

Mathematical Physics · Physics 2009-04-22 F. Bagarello , M. R. Abdollahpour , S. Triolo

A framed surface is a smooth surface in the Euclidean space with a moving frame. By using the moving frame, we can define Bertrand framed surfaces as the same idea as Bertrand framed curves. Then we find the caustics and involutes as…

Differential Geometry · Mathematics 2025-05-08 Nozomi Nakatsuyama , Masatomo Takahashi

In this paper, we study uncharged, non-conformal, and anisotropic systems with strong interactions using the gauge-gravity duality by considering Einstein-Quadratic-Axion-Dilaton action in five dimensions. In fact, we would like to gain…

High Energy Physics - Theory · Physics 2023-08-11 S. N. Sajadi , H. R. Safari

We describe an efficient algorithm to compute a conformally equivalent metric for a discrete surface, possibly with boundary, exhibiting prescribed Gaussian curvature at all interior vertices and prescribed geodesic curvature along the…

Computational Geometry · Computer Science 2021-04-13 Marcel Campen , Ryan Capouellez , Hanxiao Shen , Leyi Zhu , Daniele Panozzo , Denis Zorin

This is a survey paper of our current research on the theory of partial differential equations in conformal geometry. Our intention is to describe some of our current works in a rather brief and expository fashion. We are not giving a…

Differential Geometry · Mathematics 2008-04-25 Sun-Yung A. Chang , Jie Qing , Paul Yang

We develop an alternative approach to the study of Fourier series, based on the Short-Time-Fourier Transform (STFT) acting on $L_{\nu }^{2}(0,1)$, the space of measurable functions $f$ in ${R}$, square-integrable in $ (0,1)$, and…

Functional Analysis · Mathematics 2024-12-31 L. D. Abreu , F. Luef , M. Ziyat

Gibbs random fields corresponding to systems of real-valued spins (e.g. systems of interacting anharmonic oscillators) indexed by the vertices of unbounded degree graphs with a certain summability property are constructed. It is proven that…

Probability · Mathematics 2009-04-22 Yuri Kondratiev , Yuri Kozitsky , Tanja Pasurek

We investigate diagonal forms of degree $d$ over the function field $F$ of a smooth projective $p$-adic curve: if a form is isotropic over the completion of $F$ with respect to each discrete valuation of $F$, then it is isotropic over…

Number Theory · Mathematics 2021-04-13 Susanne Pumpluen

Topologically protected waves in the linearly polarized Maxwell's equations with gyrotropic, magneto-optic media were studied a decade ago both computationally and experimentally. This paper develops a robust tight-binding model for this…

Optics · Physics 2020-02-19 Mark J. Ablowitz , Justin T. Cole