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In this paper, we study the problem of computing a homotopy from a planar curve $C$ to a point that minimizes the area swept. The existence of such a minimum homotopy is a direct result of the solution of Plateau's problem. Chambers and…

Algebraic Topology · Mathematics 2017-07-10 Brittany Terese Fasy , Selcuk Karakoc , Carola Wenk

Toeplitz's Square Peg Problem asks whether every continuous simple closed curve in the plane contains the four vertices of a square. It has been proved for various classes of sufficiently smooth curves, some of which are dense, none of…

Metric Geometry · Mathematics 2022-03-21 Benjamin Matschke

In general relativity, an IDEAL (Intrinsic, Deductive, Explicit, ALgorithmic) characterization of a reference spacetime metric $g_0$ consists of a set of tensorial equations $T[g]=0$, constructed covariantly out of the metric $g$, its…

General Relativity and Quantum Cosmology · Physics 2019-09-20 Igor Khavkine

In textural equilibrium, partially molten materials minimise the total surface energy bound up in grain boundaries and grain-melt interfaces. Here, numerical calculations of such textural equilibrium geometries are presented for a…

Soft Condensed Matter · Physics 2018-04-12 John F. Rudge

For every group $\{\pm1\}\subseteq \Delta\subseteq (\mathbb{Z}/N\mathbb{Z})^\times$, there exists an intermediate modular curve $X_\Delta(N)$. In this paper we determine all curves $X_\Delta(N)$ whose $\mathbb{Q}$-gonality is equal to $4$,…

Number Theory · Mathematics 2024-07-23 Petar Orlić

Farin proposed a method for designing Bezier curves with monotonic curvature and torsion. Such curves are relevant in design due to their aesthetic shape. The method relies on applying a matrix M to the first edge of the control polygon of…

Numerical Analysis · Mathematics 2020-07-21 A. Cantón , L. Fernández-Jambrina , M. J. Vázquez-Gallo

Helton and Vinnikov showed that every rigidly convex curve in the real plane bounds a spectrahedron. This leads to the computational problem of explicitly producing a symmetric (positive definite) linear determinantal representation for a…

Algebraic Geometry · Mathematics 2013-12-03 Daniel Plaumann , Bernd Sturmfels , Cynthia Vinzant

In mathematics curves are typically defined as the images of continuous real functions (parametrizations) defined on a closed interval. They can also be defined as connected one-dimensional compact subsets of points. For simple curves of…

Computational Geometry · Computer Science 2015-07-01 Xizhong Zheng , Robert Rettinger

It is hereby established that, in Euclidean spaces of finite dimension, bounded self-contracted curves have finite length. This extends the main result of Daniilidis, Ley, and Sabourau (J. Math. Pures Appl. 2010) concerning continuous…

Classical Analysis and ODEs · Mathematics 2012-11-15 Aris Daniilidis , Guy David , Estibalitz Durand-Cartagena , Antoine Lemenant

Given two distinct reduced, irreducible curves of given degrees, contained in projective space but whose union is not contained in a hyperplane, what is the largest number of points of intersection they can have? When the projective space…

We consider the curves whose all normal planes are at the same distance from a fixed point and obtain some characterizations of them in the 3-dimensional Euclidean space.

General Mathematics · Mathematics 2016-05-12 Yasemin Alagoz

Let $A$ be a noetherian ring and $R_A$ be the graded ring $A[X,Y,Z,T]$. In this article we introduce the notion of a triad, which is a generalization to families of curves in ${\bf P}^3_A$ of the notion of Rao module. A triad is a complex…

Algebraic Geometry · Mathematics 2007-05-23 Robin Hartshorne , Mireille Martin-Deschamps , Daniel Perrin

In this paper, we regard the smooth quadric threefold $Q_{3}$ as Lagrangian Grassmannian and search for fixed rational curves of low degree in $Q_{3}$ with respect to a torus action, which is the maximal subgroup of the special linear group…

Algebraic Geometry · Mathematics 2025-07-08 Kiryong Chung , Sukmoon Huh , Sang-Bum Yoo

Let $A$ be a local noetherian ring and $N$ be a locally sheaf on the projective space $P^3_A$ : one proves easily that there exists a family $C$ of (smooth connected) curves contained in $P^3_A$, flat over $A$, and an integer $h$ such that…

alg-geom · Mathematics 2007-05-23 Robin Hartshorne , Mireille Martin-Deschamps , Daniel Perrin

The mapping class group invariant ideal cell decomposition of the Teichmueller space of a punctured surface times an open simplex has been used in a number of computations. This paper answers a question about the asymptotics of this…

Geometric Topology · Mathematics 2007-07-11 R. C. Penner , Greg McShane

We introduce the triangular prism equations (TPE) for fusion categories, obtained by evaluating triangular prisms in terms of tetrahedra. Using an oriented graphical calculus, we show that the geometric symmetries of the regular tetrahedron…

Quantum Algebra · Mathematics 2025-12-16 Zhengwei Liu , Sebastien Palcoux , Yunxiang Ren , Gert Vercleyen

In the first part of this paper we study scrollers and linearly joined varieties. A particular class of varieties, of important interest in classical Geometry are Cohen--Macaulay varieties of minimal degree. They appear naturally studying…

Commutative Algebra · Mathematics 2009-09-29 Marcel Morales

A notion of dual curve for pseudoholomorphic curves in 4--manifolds turns out to be possible only if the notion of almost complex structure structure is slightly generalized. The resulting structure is as easy (perhaps easier) to work with,…

Differential Geometry · Mathematics 2007-05-23 Benjamin McKay

When a pair of non-incident edges of a tetrahedron is chosen, the midpoints of the remaining 4 edges are the vertices of a planar parallelogram. A formula is given in terms of the six edge lengths for the area of this parallelogram. It is…

Metric Geometry · Mathematics 2019-09-11 David N. Yetter

The Complex of Curves on a Surface is a simplicial complex whose vertices are homotopy classes of simple closed curves, and whose simplices are sets of homotopy classes which can be realized disjointly. It is not hard to see that the…

Geometric Topology · Mathematics 2009-10-31 Howard A. Masur , Yair N. Minsky