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The fine curve complex of a surface is a simplicial complex whose vertices are essential simple closed curves and whose $k$-simplices are collections of $k+1$ disjoint curves. We prove that the fine curve complex is homotopy equivalent to…

Geometric Topology · Mathematics 2026-02-11 Ryan Dickmann , Zachary Himes , Alexander Nolte , Roberta Shapiro

Tight triangulations are exotic, but highly regular objects in combinatorial topology. A triangulation is tight if all its piecewise linear embeddings into a Euclidean space are as convex as allowed by the topology of the underlying…

Geometric Topology · Mathematics 2018-10-24 Benjamin A. Burton , Basudeb Datta , Nitin Singh , Jonathan Spreer

A $k$-uniform, $d$-regular instance of Exact Cover is a family of $m$ sets $F_{n,d,k} = \{ S_j \subseteq \{1,...,n\} \}$, where each subset has size $k$ and each $1 \le i \le n$ is contained in $d$ of the $S_j$. It is satisfiable if there…

Computational Complexity · Computer Science 2015-03-05 Cristopher Moore

An outerplanar graph is a planar graph that has a planar drawing with all vertices on the unbounded face. The matching complex of a graph is the simplicial complex whose faces are subsets of disjoint edges of the graph. In this paper we…

Combinatorics · Mathematics 2024-11-08 Margaret Bayer , Marija Jelić Milutinović , Julianne Vega

Deep implicit surfaces excel at modeling generic shapes but do not always capture the regularities present in manufactured objects, which is something simple geometric primitives are particularly good at. In this paper, we propose a…

Computer Vision and Pattern Recognition · Computer Science 2022-09-09 Subeesh Vasu , Nicolas Talabot , Artem Lukoianov , Pierre Baqué , Jonathan Donier , Pascal Fua

Let $G$ be a locally compact totally disconnected topological group. Under a necessary mild assumption, we show that the irreducible unitary representations of $G$ are uniformly admissible if and only if the irreducible smooth…

Representation Theory · Mathematics 2018-10-16 Uriya A. First , Thomas Rüd

We provide a simple characterization of simplicial complexes on few vertices that embed into the $d$-sphere. Namely, a simplicial complex on $d+3$ vertices embeds into the $d$-sphere if and only if its non-faces do not form an intersecting…

Combinatorics · Mathematics 2023-11-10 Florian Frick , Mirabel Hu , Verity Scheel , Steven Simon

Deep convolutional neural network (CNN) based models are vulnerable to the adversarial attacks. One of the possible reasons is that the embedding space of CNN based model is sparse, resulting in a large space for the generation of…

Computer Vision and Pattern Recognition · Computer Science 2022-05-17 Haozhe Liu , Haoqin Ji , Yuexiang Li , Nanjun He , Haoqian Wu , Feng Liu , Linlin Shen , Yefeng Zheng

We introduce the notion of a combinatorial $n$-od cover, for $n \geq 3$, which is a tool that may be used to show that certain continua embedded in the plane are not simple $n$-od-like. Using this tool, we generalize a classic example of…

General Topology · Mathematics 2025-06-16 Logan C. Hoehn , Hugo Adrian Maldonado-Garcia

A graph G is well-covered if all its maximal independent sets are of the same cardinality. Assume that a weight function w is defined on its vertices. Then G is w-well-covered if all maximal independent sets are of the same weight. For…

Discrete Mathematics · Computer Science 2012-10-26 Vadim Levit , David Tankus

We describe a provably complete algorithm for the generation of a tight, possibly exact superset of all combinatorially distinct simple n-facet polytopes in R^d, along with their graphs, f-vectors, and face lattices. The technique applies…

Combinatorics · Mathematics 2009-08-13 Sandeep Koranne , Anand Kulkarni

We study the \emph{picture space} $X^d(G)$ of all embeddings of a finite graph $G$ as point-and-line arrangements in an arbitrary-dimensional projective space, continuing previous work on the planar case. The picture space admits a natural…

Combinatorics · Mathematics 2011-10-05 Thomas Enkosky , Jeremy L. Martin

Complex prediction models such as deep learning are the output from fitting machine learning, neural networks, or AI models to a set of training data. These are now standard tools in science. A key challenge with the current generation of…

Machine Learning · Computer Science 2022-10-21 Meng Liu , Tamal K. Dey , David F. Gleich

A uniform space $X$ is said to be proximally fine if every proximally continuous map on $X$ into a uniform is uniformly continuous. We supply a proof that every topological group which is functionnaly generated by its precompact subsets is…

General Topology · Mathematics 2019-04-30 Ahmed Bouziad

Kernelization algorithms are polynomial-time reductions from a problem to itself that guarantee their output to have a size not exceeding some bound. For example, d-Set Matching for integers d>2 is the problem of finding a matching of size…

Data Structures and Algorithms · Computer Science 2018-12-10 Holger Dell , Dániel Marx

While robotic manipulation of rigid objects is quite straightforward, coping with deformable objects is an open issue. More specifically, tasks like tying a knot, wiring a connector or even surgical suturing deal with the domain of…

Computer Vision and Pattern Recognition · Computer Science 2018-10-11 Daniele De Gregorio , Gianluca Palli , Luigi Di Stefano

In this work, we focus on the task of learning and representing dense correspondences in deformable object categories. While this problem has been considered before, solutions so far have been rather ad-hoc for specific object types (i.e.,…

Computer Vision and Pattern Recognition · Computer Science 2020-11-26 Natalia Neverova , David Novotny , Vasil Khalidov , Marc Szafraniec , Patrick Labatut , Andrea Vedaldi

Empirical data, on which deep learning relies, has substantial internal structure, yet prevailing theories often disregard this aspect. Recent research has led to the definition of structured data ensembles, aimed at equipping established…

Disordered Systems and Neural Networks · Physics 2023-11-13 Andrea Baroffio , Pietro Rotondo , Marco Gherardi

Implicit surface representations, such as signed-distance functions, combined with deep learning have led to impressive models which can represent detailed shapes of objects with arbitrary topology. Since a continuous function is learned,…

Computer Vision and Pattern Recognition · Computer Science 2021-02-08 Edgar Tretschk , Ayush Tewari , Vladislav Golyanik , Michael Zollhöfer , Carsten Stoll , Christian Theobalt

Recently, implicit neural representations have gained popularity for learning-based 3D reconstruction. While demonstrating promising results, most implicit approaches are limited to comparably simple geometry of single objects and do not…

Computer Vision and Pattern Recognition · Computer Science 2020-08-04 Songyou Peng , Michael Niemeyer , Lars Mescheder , Marc Pollefeys , Andreas Geiger