English
Related papers

Related papers: Vertex-Faithful Regular Polyhedra

200 papers

We complete the program for determining the full automorphism groups of all parafermion vertex operator algebras associated with simple Lie algebras and positive integral levels. We show that the full automorphism group of the parafermion…

Quantum Algebra · Mathematics 2024-09-25 Ching Hung Lam , Xingjun Lin , Hiroki Shimakura

We give a sharp bound for the automorphism group of a cubic simple graph with a given number of vertices. For each number of vertices we give an explicit graph attaining the bound, and prove its uniqueness in special cases.

Combinatorics · Mathematics 2007-05-23 Michael A. van Opstall , Razvan Veliche

Deciding whether the union of two convex polyhedra is itself a convex polyhedron is a basic problem in polyhedral computations; having important applications in the field of constrained control and in the synthesis, analysis, verification…

Computational Geometry · Computer Science 2009-08-10 Roberto Bagnara , Patricia M. Hill , Enea Zaffanella

We demonstrate the construction of several families of flexible polyhedra by extending Bricard octahedra to form larger composite flexible polyhedra. These flexible polyhedra are of genus 0 and 1, have dihedral angles that are non-constant…

Metric Geometry · Mathematics 2010-11-24 Gerald D. Nelson

The class of the hypercomplex pseudo-Hermitian manifolds is considered. The flatness of the considered manifolds with the 3 parallel complex structures is proved. Conformal transformations of the metrics are introduced. The conformal…

Differential Geometry · Mathematics 2012-03-27 Kostadin Gribachev , Mancho Manev , Stancho Dimiev

In this paper we build an abstract description of vertex algebras from their basic axioms. Starting with Borcherds' notion of a vertex group, we naturally construct a family of multilinear singular maps parameterised by trees. These…

Quantum Algebra · Mathematics 2007-05-23 Craig T. Snydal

We give very flexible, concrete constructions of discrete and faithful epresentations of right-angled Artin groups into higher-rank Lie groups. Using the geometry of the associated symmetric spaces and the combinatorics of the groups, we…

Group Theory · Mathematics 2014-10-01 Stephen Wang

We prove that any simple polytope (and some non-simple polytopes) in $\mathbb R^3$ admits an inscribed regular octahedron.

Combinatorics · Mathematics 2013-02-13 Arseniy Akopyan , Roman Karasev

We show that several classes of polyhedra are joined by a sequence of O(1) refolding steps, where each refolding step unfolds the current polyhedron (allowing cuts anywhere on the surface and allowing overlap) and folds that unfolding into…

Computational Geometry · Computer Science 2023-10-27 Erik D. Demaine , Martin L. Demaine , Jenny Diomidova , Tonan Kamata , Ryuhei Uehara , Hanyu Alice Zhang

We present two algorithms for unfolding the surface of any polyhedron, all of whose faces are triangles, to a nonoverlapping, connected planar layout. The surface is cut only along polyhedron edges. The layout is connected, but it may have…

Computational Geometry · Computer Science 2010-01-21 Erik D. Demaine , David Eppstein , Jeff Erickson , George W. Hart , Joseph O'Rourke

This paper is devoted to the study the $m$-point homogeneity property and the point homogeneity degree for finite metric spaces. Since the vertex sets of regular polytopes, as well as of some their generalizations, are homogeneous, we pay…

Metric Geometry · Mathematics 2024-06-13 Valerii N. Berestovskii , Yurii G. Nikonorov

An unfolding of a polyhedron is produced by cutting the surface and flattening to a single, connected, planar piece without overlap (except possibly at boundary points). It is a long unsolved problem to determine whether every polyhedron…

Computational Geometry · Computer Science 2007-05-23 Mirela Damian , Robin Flatland , Joseph O'Rourke

An edge-unfolding of a polyhedron is produced by cutting along edges and flattening the faces to a *net*, a connected planar piece with no overlaps. A *grid unfolding* allows additional cuts along grid edges induced by coordinate planes…

Computational Geometry · Computer Science 2007-05-23 Mirela Damian , Robin Flatland , Joseph O'Rourke

By studying the action of the Weyl group of a simple Lie algebra on its root lattice, we construct torsion free subgroups of small and explicitly determined index in a large infinite class of Coxeter groups. One spin-off is the construction…

Geometric Topology · Mathematics 2009-11-09 Brent Everitt , Robert B. Howlett

We prove that every three-dimensional polyhedron is uniquely determined by its dihedral angles and edge lengths, even if nonconvex or self-intersecting, under two plausible sufficient conditions: (i) the polyhedron has only convex faces and…

Geometric Topology · Mathematics 2023-07-28 Yunhi Cho , Seonhwa Kim

A small cover is a closed smooth manifold of dimension $n$ having a locally standard $\mathbb{Z}_2^n$-action whose orbit space is isomorphic to a simple polytope. A typical example of small covers is a real projective toric manifold (or,…

Algebraic Topology · Mathematics 2017-03-16 Suyoung Choi , Hanchul Park

Polyhedral surfaces are fundamental objects in architectural geometry and industrial design. Whereas closeness of a given mesh to a smooth reference surface and its suitability for numerical simulations were already studied extensively, the…

Metric Geometry · Mathematics 2017-03-17 Felix Günther , Caigui Jiang , Helmut Pottmann

Herein we study conformal vectors of a Z-graded vertex algebra of (strong) CFT type. We prove that the full vertex algebra automorphism group transitively acts on the set of the conformal vectors of strong CFT type if the vertex algebra is…

Quantum Algebra · Mathematics 2019-10-29 Yuto Moriwaki

We borrow a classical construction from the study of rational billiards in dynamical systems known as the "unfolding construction" and show that it can be used to study the automorphism group of a Platonic surface. More precisely, the…

Geometric Topology · Mathematics 2020-05-13 David Aulicino

In this note we give a direct method to classify all stable forms on $\R^n$ as well as to determine their automorphism groups. We show that in dimension 6,7,8 stable forms coincide with non-degnerate forms. We present necessary conditions…

Differential Geometry · Mathematics 2008-05-03 Hong-Van Le , Martin Panak , Jiri Vanzura
‹ Prev 1 3 4 5 6 7 10 Next ›