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By using the metric projection onto a closed self-dual cone of the Euclidean space, M. S. Gowda, R. Sznajder and J. Tao have defined generalized lattice operations, which in the particular case of the nonnegative orthant of a Cartesian…

Functional Analysis · Mathematics 2013-01-28 A. B. Németh , S. Z. Németh

Goldberg & Gott (2008) developed six error measures to rate flat map projections on their verisimilitude to the sphere: Isotropy, Area, Flexion, Skewness, Distances, and Boundary Cuts. The first two depend on the metric of the projection,…

Instrumentation and Methods for Astrophysics · Physics 2021-02-17 J. Richard Gott , David M. Goldberg , Robert J. Vanderbei

Euclidean distance geometry is the study of Euclidean geometry based on the concept of distance. This is useful in several applications where the input data consists of an incomplete set of distances, and the output is a set of points in…

Quantitative Methods · Quantitative Biology 2012-05-03 Leo Liberti , Carlile Lavor , Nelson Maculan , Antonio Mucherino

In 1983, Hartle and Hawking proposed the no-boundary proposal, suggesting that the universe has no beginning in the sense of a spacetime singularity or boundary. Nevertheless, there is an origin of time. Mathematically, this involves…

Differential Geometry · Mathematics 2026-03-26 N. E. Rieger , W. Hasse

This paper concentrates on the homogeneous (conformal) model of Euclidean space (Horosphere) with subspaces that intuitively correspond to Euclidean geometric objects in three dimensions. Mathematical details of the construction and…

Rings and Algebras · Mathematics 2013-06-06 Eckhard Hitzer

Set representations are the foundation of various set-based approaches in state estimation, reachability analysis and fault diagnosis. In this paper, we investigate spectrahedral shadows, a class of nonlinear geometric objects previously…

Systems and Control · Electrical Eng. & Systems 2025-04-15 Chengrui Wang , Haohao Qiu , Sibo Yao , James Lam

Let $X_D$ denote the Hilbert modular surface $\HH \times \HH^- / \SL_2(\OD)$. In \cite{HZ76}, F. Hirzebruch and D. Zagier introduced Hirzebruch-Zagier cycles, that could also be called twisted diagonals. These are maps $\HH \to \HH \times…

Algebraic Geometry · Mathematics 2013-11-06 Christian Weiß

Morse functions with exactly two singular points on homotopy spheres and canonical projections of spheres are generalized as special generic maps. A special generic map is, roughly, a smooth map represented as the composition of a smooth…

Algebraic Geometry · Mathematics 2025-03-28 Naoki Kitazawa

In the early 1980's an elementary algorithm for computing conformal maps was discovered by R. K\"uhnau and the first author. The algorithm is fast and accurate, but convergence was not known. Given points z_0,...,z_n in the plane, the…

Complex Variables · Mathematics 2007-05-23 Donald E. Marshall , Steffen Rohde

A new cosmic shear analysis pipeline SUNGLASS (Simulated UNiverses for Gravitational Lensing Analysis and Shear Surveys) is introduced. SUNGLASS is a pipeline that rapidly generates simulated universes for weak lensing and cosmic shear…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 A. Kiessling , A. F. Heavens , A. N. Taylor

A family of sequences produced by a non-homogeneous linear recurrence formula derived from the geometry of circles inscribed in lenses is introduced and studied. Mysterious ``underground'' sequences underlying them are discovered in this…

Number Theory · Mathematics 2007-10-18 Jerzy Kocik

The pentagram map, introduced by R. Schwartz, is defined by the following construction: given a polygon as input, draw all of its "shortest" diagonals, and output the smaller polygon which they cut out. We employ the machinery of cluster…

Combinatorics · Mathematics 2011-04-18 Max Glick

Conics and Cartesian ovals are very important curves in various fields of science. Also aspheric curves based on conics are useful in optics. Superconic curves recently suggested by A. Greynolds are extensions of both conics and Cartesian…

General Mathematics · Mathematics 2016-09-21 Sunggoo Cho

In this paper we complete the proof began by A. Polishchuk and E. Zaslow (math.AG/9801119) of a weak version of Kontsevich's homological mirror symmetry conjecture for elliptic curves. The main difference to the work of Polishchuk and…

Algebraic Geometry · Mathematics 2007-05-23 Bernd Kreussler

Distance Geometry Problem (DGP) and Nonlinear Mapping (NLM) are two well established questions: Distance Geometry Problem is about finding a Euclidean realization of an incomplete set of distances in a Euclidean space, whereas Nonlinear…

Computational Geometry · Computer Science 2019-05-10 Alain Franc , Pierre Blanchard , Olivier Coulaud

In the 1770s, Euler wrote a series of papers (E563, E691 and E692) about finding the ellipse with minimal area or perimeter in the family of all ellipses passing through a fixed set of points. This is a translation of all three papers from…

History and Overview · Mathematics 2025-09-17 Leonhard Euler , Jonathan David Evans

A fold map is a smooth map at each singular point of which it is represented as the product map of a Morse function and the identity map on an open ball. A special generic map is a fold map such that the Morse function can be taken as a…

Algebraic Topology · Mathematics 2021-09-20 Naoki Kitazawa

A tutorial introduction to projective geometric algebra (PGA), a modern, coordinate-free framework for doing euclidean geometry. PGA features: uniform representation of points, lines, and planes; robust, parallel-safe join and meet…

General Mathematics · Mathematics 2020-08-19 Charles G. Gunn

The Searchlight Scheduling Problem was first studied in 2D polygons, where the goal is for point guards in fixed positions to rotate searchlights to catch an evasive intruder. Here the problem is extended to 3D polyhedra, with the guards…

Computational Geometry · Computer Science 2015-03-19 Giovanni Viglietta

We present the first utterly self-supervised network for dense correspondence mapping between non-isometric shapes. The task of alignment in non-Euclidean domains is one of the most fundamental and crucial problems in computer vision. As 3D…

Computer Vision and Pattern Recognition · Computer Science 2021-12-15 Dvir Ginzburg , Dan Raviv
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