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This paper presents a unified geometric framework for the statistical analysis of a general ill-posed linear inverse model which includes as special cases noisy compressed sensing, sign vector recovery, trace regression, orthogonal matrix…

Statistics Theory · Mathematics 2020-07-27 T. Tony Cai , Tengyuan Liang , Alexander Rakhlin

Given an ordered sequence of $N$-choose-2 integers, we give necessary and sufficient conditions to have an ordered collection of $N$ simple closed curves on a torus such that the algebraic pairwise intersections of those curves are the…

Geometric Topology · Mathematics 2025-08-25 Ferit Öztürk

We investigate resolutions of heterotic orbifolds using toric geometry. Our starting point is provided by the recently constructed heterotic models on explicit blowup of C^n/Z_n singularities. We show that the values of the relevant…

High Energy Physics - Theory · Physics 2008-11-26 Stefan Groot Nibbelink , Tae-Won Ha , Michele Trapletti

Geometric number systems, obtained by extending the real number system to include new anticommuting square roots of +1 and -1, provide a royal road to higher mathematics by largely sidestepping the tedious languages of tensor analysis and…

General Mathematics · Mathematics 2017-07-21 Garret Sobczyk

A hybrid imaging system consisting of a standard CT scanner and a low-profile photon-counting detector insert in contact with the patient's body has been used to produce ultrahigh-resolution images in a limited volume in chest scans of…

Medical Physics · Physics 2022-09-05 Dakota H. King , Eric E. Bennett , Dumitru Mazilu , Muyang Wang , Marcus Y. Chen , Han Wen

Seismic imaging is the numerical process of creating a volumetric representation of the subsurface geological structures from elastic waves recorded at the surface of the Earth. As such, it is widely utilized in the energy and construction…

Geophysics · Physics 2024-11-05 Juan Romero , Wolfgang Heidrich , Nick Luiken , Matteo Ravasi

The strong geodetic problem on a graph $G$ is to determine a smallest set of vertices such that by fixing one shortest path between each pair of its vertices, all vertices of $G$ are covered. To do this as efficiently as possible, strong…

Combinatorics · Mathematics 2018-04-02 Valentin Gledel , Vesna Iršič , Sandi Klavžar

In this manuscript, we study the interplay between symmetry and topology with a focus on the $Z_2$ topological index of 2D/3D topological insulators and high-order topological insulators. We show that in the presence of either a…

Mesoscale and Nanoscale Physics · Physics 2020-08-06 Heqiu Li , Kai Sun

The index of a Riemannian symmetric space is the minimal codimension of a proper totally geodesic submanifold (Onishchik, 1980). There is a conjecture by the first two authors for how to calculate the index. In this paper we give an…

Differential Geometry · Mathematics 2019-05-16 Jürgen Berndt , Carlos Olmos , Juan Sebastián Rodríguez

This paper is devoted to presenting a new approach to determine the intersection of two quadrics based on the detailed analysis of its projection in the plane (the so called cutcurve) allowing to perform the corresponding lifting correctly.…

Computational Geometry · Computer Science 2019-06-26 Alexandre Trocado , Laureano Gonzalez-Vega

The geometry of a graph $G$ embedded on a closed oriented surface $S$ can be probed by counting the intersections of $G$ with closed curves on $S$. Of special interest is the map $c \mapsto \mu_G(c)$ counting the minimum number of…

Computational Geometry · Computer Science 2025-10-22 Vincent Delecroix , Oscar Fontaine , Francis Lazarus

We address the problem of computing a single linkage dendrogram. A possible approach is to: (i) Form an edge weighted graph $G$ over the data, with edge weights reflecting dissimilarities. (ii) Calculate the MST $T$ of $G$. (iii) Break the…

Data Structures and Algorithms · Computer Science 2019-11-04 Huanbiao Zhu , Werner Stuetzle

A walk $W$ between vertices $u$ and $v$ of a graph $G$ is called a {\em tolled walk between $u$ and $v$} if $u$, as well as $v$, has exactly one neighbour in $W$. A set $S \subseteq V(G)$ is {\em toll convex} if the vertices contained in…

Discrete Mathematics · Computer Science 2020-09-15 Mitre C. Dourado

We present a new method for visualizing implicit real algebraic curves inside a bounding box in the $2$-D or $3$-D ambient space based on numerical continuation and critical point methods. The underlying techniques work also for tracing…

Symbolic Computation · Computer Science 2019-12-17 Changbo Chen , Wenyuan Wu , Yong Feng

In this article we present theoretical and computational results on the existence of polyhedral embeddings of graphs. The emphasis is on cubic graphs. We also describe an efficient algorithm to compute all polyhedral embeddings of a given…

Combinatorics · Mathematics 2023-06-22 Gunnar Brinkmann , Thomas Tucker , Nico Van Cleemput

Slimness of a graph measures the local deviation of its metric from a tree metric. In a graph $G=(V,E)$, a geodesic triangle $\bigtriangleup(x,y,z)$ with $x, y, z\in V$ is the union $P(x,y) \cup P(x,z) \cup P(y,z)$ of three shortest paths…

Discrete Mathematics · Computer Science 2023-06-22 Feodor F. Dragan , Abdulhakeem Mohammed

Fitting concentric geometric objects to digitized data is an important problem in many areas such as iris detection, autonomous navigation, and industrial robotics operations. There are two common approaches to fitting geometric shapes to…

Computer Vision and Pattern Recognition · Computer Science 2021-03-10 Ali A. Al-Sharadqah , Lorenzo Rull

Given a hypergraph $\mathcal{H}$, we introduce a new class of evaluation toric codes called edge codes derived from $\mathcal{H}$. We analyze these codes, focusing on determining their basic parameters. We provide estimations for the…

Commutative Algebra · Mathematics 2024-04-04 Delio Jaramillo-Velez

The problem of finding an appropriate geometrical/physical index for measuring a degree of inhomogeneity for a given space-time manifold is posed. Interrelations with the problem of understanding the gravitational/informational entropy are…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roustam Zalaletdinov

Some projective wonderful models for the complement of a toric arrangement in a n-dimensional algebraic torus T were constructed in [3]. In this paper we describe their integer cohomology rings by generators and relations.

Algebraic Topology · Mathematics 2019-02-13 Corrado De Concini , Giovanni Gaiffi