English
Related papers

Related papers: Involutions of polynomially parametrized surfaces

200 papers

Many man-made objects are characterised by a shape that is symmetric along one or more planar directions. Estimating the location and orientation of such symmetry planes can aid many tasks such as estimating the overall orientation of an…

Computer Vision and Pattern Recognition · Computer Science 2021-07-01 Mihaela Cătălina Stoian , Tommaso Cavallari

We discuss methods to construct a polynomial parametrization of some interesting knotted surfaces (knotted spheres, knotted tori and knotted planes) and provide examples.

Geometric Topology · Mathematics 2026-02-17 Louis H. Kauffman , Tumpa Mahato , Rama Mishra

Ihe first author presented an efficient algorithm for computing involutive (and reduced Groebner) bases. In this paper, we consider a modification of this algorithm which simplifies matters to understand it and to implement. We prove…

Rings and Algebras · Mathematics 2011-08-17 Vladimir P. Gerdt , Amir Hashemi , Benyamin M. -Alizadeh

We use equivariant surgery to classify all involutions on closed surfaces, up to isomorphism. Work on this problem is classical, dating back to the nineteenth century, but some questions seem to have been left unanswered. We give a modern…

Geometric Topology · Mathematics 2016-12-28 Daniel Dugger

Topological invariants allow to characterize Hamiltonians, predicting the existence of topologically protected in-gap modes. Those invariants can be computed by tracing the evolution of the occupied wavefunctions under twisted boundary…

Mesoscale and Nanoscale Physics · Physics 2018-04-04 D. Carvalho , N. A. Garcia-Martinez , J. L. Lado , J. Fernandez-Rossier

The persistence diagram (PD) is an increasingly popular topological descriptor. By encoding the size and prominence of topological features at varying scales, the PD provides important geometric and topological information about a space.…

We study iterations of two classical constructions, the evolutes and involutes of plane curves, and we describe the limiting behavior of both constructions on a class of smooth curves with singularities given by their support functions.…

Dynamical Systems · Mathematics 2016-09-06 M. Arnold , D. Fuchs , I. Izmestiev , S. Tabachnikov , E. Tsukerman

We study numerical computation of conformal invariants of domains in the complex plane. In particular, we provide an algorithm for computing the conformal capacity of a condenser. The algorithm applies for wide kind of geometries: domains…

Complex Variables · Mathematics 2020-08-19 Mohamed M S Nasser , Matti Vuorinen

We define a convolution operation on the set of polyominoes and use it to obtain a criterion for a given polyomino not to tile the plane (rotations and translations allowed). We apply the criterion to several families of polyominoes, and…

Combinatorics · Mathematics 2007-05-23 Ali Ulas Ozgur Kisisel

We introduce a theoretical framework for differentiable surface evolution that allows discrete topology changes through the use of topological derivatives for variational optimization of image functionals. While prior methods for inverse…

Computer Vision and Pattern Recognition · Computer Science 2023-08-22 Ishit Mehta , Manmohan Chandraker , Ravi Ramamoorthi

We present a convolutional approach to reflection symmetry detection in 2D. Our model, built on the products of complex-valued wavelet convolutions, simplifies previous edge-based pairwise methods. Being parameter-centered, as opposed to…

Computer Vision and Pattern Recognition · Computer Science 2016-09-20 Marcelo Cicconet , Vighnesh Birodkar , Mads Lund , Michael Werman , Davi Geiger

Given a central simple algebra with involution over an arbitrary field, \'etale subalgebras contained in the space of symmetric elements are investigated. The method emphasizes the similarities between the various types of involutions and…

K-Theory and Homology · Mathematics 2017-10-20 Karim Johannes Becher , Nicolas Grenier-Boley , Jean-Pierre Tignol

For many fundamental problems in computational topology, such as unknot recognition and $3$-sphere recognition, the existence of a polynomial-time solution remains unknown. A major algorithmic tool behind some of the best known algorithms…

Computational Geometry · Computer Science 2024-03-08 Benjamin A. Burton , Alexander He

We study the computation of local approximations of invariant manifolds of parabolic fixed points and parabolic periodic orbits of periodic vector fields. If the dimension of these manifolds is two or greater, in general, it is not possible…

Dynamical Systems · Mathematics 2016-03-09 Inmaculada Baldomá , Ernest Fontich , Pau Martín

We present a novel algorithm for deciding whether a given planar curve is an image of a given spatial curve, obtained by a central or a parallel projection with unknown parameters. The motivation comes from the problem of establishing a…

Algebraic Geometry · Mathematics 2019-03-12 Joseph M. Burdis , Irina A. Kogan , Hoon Hong

We consider the problem of learning a function respecting a symmetry from among a class of symmetries. We develop a unified framework that enables symmetry discovery across a broad range of subgroups including locally symmetric, dihedral…

Machine Learning · Computer Science 2023-10-30 Pavan Karjol , Rohan Kashyap , Aditya Gopalan , Prathosh A. P

We study the shape of inflated surfaces introduced in \cite{B1} and \cite{P1}. More precisely, we analyze profiles of surfaces obtained by inflating a convex polyhedron, or more generally an almost everywhere flat surface, with a symmetry…

Differential Geometry · Mathematics 2015-05-13 Igor Pak , Jean-Marc Schlenker

In this paper, we propose a simple yet effective method to endow deep 3D models with rotation invariance by expressing the coordinates in an intrinsic frame determined by the object shape itself. Key to our approach is to find such an…

Computer Vision and Pattern Recognition · Computer Science 2019-10-22 Zelin Xiao , Hongxin Lin , Renjie Li , Hongyang Chao , Shengyong Ding

Symmetry detection and discrimination are of fundamental meaning in science, technology, and engineering. This paper introduces reflection invariants and defines the directional moment to detect symmetry for shape analysis and object…

Computer Vision and Pattern Recognition · Computer Science 2017-06-02 Erbo Li , Hua Li

We use machine learning to classify examples of braids (or flat braids) as trivial or non-trivial. Our ML takes form of supervised learning using neural networks (multilayer perceptrons). When they achieve good results in classification, we…

Geometric Topology · Mathematics 2023-07-25 Alexei Lisitsa , Mateo Salles , Alexei Vernitski