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Related papers: Band Unfoldings and Prismatoids: A Counterexample

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Starting with the unsolved "D\"urer's problem" of edge-unfolding a convex polyhedron to a net, we specialize and generalize (a) the types of cuts permitted, and (b) the polyhedra shapes, to highlight both advances established and which…

Computational Geometry · Computer Science 2019-08-21 Joseph O'Rourke

A surface is considered flexible if it allows a continuous deformation that preserves both metric and smoothness. We introduce a novel construction method, called 'base + crinkle,' for generating a broad class of non-self-intersecting…

Metric Geometry · Mathematics 2025-11-11 Zeyuan He , Simon D. Guest

An unzipping of a polyhedron P is a cut-path through its vertices that unfolds P to a non-overlapping shape in the plane. It is an open problem to decide if every convex P has an unzipping. Here we show that there are nearly flat convex…

Computational Geometry · Computer Science 2018-02-07 Joseph O'Rourke

We consider a new treatment for making polyhedron nets referred to as ``apple peel unfolding'': drawing the nets as if we were peeling off appleskins. We define apple peel unfolding strictly and implement a program that derives the…

Computational Geometry · Computer Science 2026-04-20 Takashi Yoshino , Supanut Chaidee

This paper presents an additional class of regular polyhedra--envelope polyhedra--made of regular polygons, where the arrangement of polygons (creating a single surface) around each vertex is identical; but dihedral angles between faces…

Metric Geometry · Mathematics 2019-08-16 J. Richard Gott

We prove two results about transforming any convex polyhedron, modeled as a linkage L of its edges. First, if we subdivide each edge of L in half, then L can be continuously flattened into a plane. Second, if L is equilateral and we again…

Computational Geometry · Computer Science 2024-12-20 Erik D. Demaine , Martin L. Demaine , Markus Hecher , Rebecca Lin , Victor H. Luo , Chie Nara

When drawing graphs whose edges and nodes contain text or graphics, such informa tion needs to be displayed without overlaps, either as part of the initial layout or as a post-processing step. The core problem in removing overlaps lies in…

Discrete Mathematics · Computer Science 2016-09-08 Yifan Hu

We present a computational approach for unfolding 3D shapes isometrically into the plane as a single patch without overlapping triangles. This is a hard, sometimes impossible, problem, which existing methods are forced to soften by allowing…

Given two parallelisms of a projective space we describe a construction, called blending, that yields a (possibly new) parallelism of this space. For a projective double space $(\mathbb{P},\parallel_\ell,\parallel_r)$ over a quaternion skew…

Algebraic Geometry · Mathematics 2024-02-02 Hans Havlicek , Stefano Pasotti , Silvia Pianta

The band-unfolding method is widely used to calculate the effective band structures of a disordered system from its supercell model. The unfolded band structures show the crystallographic symmetry of the underlying structure, where the…

Materials Science · Physics 2017-01-18 Yuji Ikeda , Abel Carreras , Atsuto Seko , Atsushi Togo , Isao Tanaka

We prove that, for any two polyhedral manifolds $\mathcal P, \mathcal Q$, there is a polyhedral manifold $\mathcal I$ such that $\mathcal P, \mathcal I$ share a common unfolding and $\mathcal I,\mathcal Q$ share a common unfolding. In other…

Computational Geometry · Computer Science 2025-10-08 Lily Chung , Erik D. Demaine , Jenny Diomidova , Tonan Kamata , Jayson Lynch , Ryuhei Uehara , Hanyu Alice Zhang

We prove that, for any two polyhedral manifolds $\mathcal P,\mathcal Q$, there is a polyhedral manifold $\mathcal I$ such that $\mathcal P,\mathcal I$ share a common unfolding and $\mathcal I,\mathcal Q$ share a common unfolding. In other…

Computational Geometry · Computer Science 2025-11-18 Lily Chung , Erik D. Demaine , Jenny Diomidova , Tonan Kamata , Jayson Lynch , Ryuhei Uehara , Hanyu Alice Zhang

Coupled and shape-tailored metallic nanoparticles are known to exhibit hybridized plasmon resonances. This Letter discuss the optical properties of a complementary system formed by overlapped nanovoid dimers buried in gold and filled with…

Materials Science · Physics 2009-11-13 I. Romero , T. V. Teperik , F. J. Garcia de Abajo

Eyelid shape is integral to identity and likeness in human facial modeling. Human eyelids are diverse in appearance with varied skin fold and epicanthal fold morphology between individuals. Existing parametric face models express eyelid…

Graphics · Computer Science 2024-10-18 Lohit Petikam , Charlie Hewitt , Fatemeh Saleh , Tadas Baltrušaitis

This note proves that every polar zonohedron has an edge-unfolding to a non-overlapping net.

Computational Geometry · Computer Science 2023-02-17 Joseph O'Rourke

Connectivity is a central notion of graph theory and plays an important role in graph algorithm design and applications. With emerging new applications in networks, a new type of graph connectivity problem has been getting more…

Discrete Mathematics · Computer Science 2020-12-22 Rupei Xu , Warren Shull

This article is concerned with the approximation of unbounded convex sets by polyhedra. While there is an abundance of literature investigating this task for compact sets, results on the unbounded case are scarce. We first point out the…

Optimization and Control · Mathematics 2023-05-04 Daniel Dörfler

Graph matching consists of aligning the vertices of two unlabeled graphs in order to maximize the shared structure across networks; when the graphs are unipartite, this is commonly formulated as minimizing their edge disagreements. In this…

Machine Learning · Statistics 2021-04-13 Jesús Arroyo , Carey E. Priebe , Vince Lyzinski

It is well-known that the convex and concave envelope of a multilinear polynomial over a box are polyhedral functions. Exponential-sized extended and projected formulations for these envelopes are also known. We consider the convexification…

Optimization and Control · Mathematics 2021-06-14 Yibo Xu , Warren Adams , Akshay Gupte

The prism over a graph $G$ is the Cartesian product of $G$ with the complete graph on two vertices. A graph $G$ is prism-hamiltonian if the prism over $G$ is hamiltonian. We prove that every polyhedral graph (i.e. 3-connected planar graph)…

Combinatorics · Mathematics 2021-04-12 Simon Špacapan