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Let $G$ be a graph with the usual shortest-path metric. A graph is $\delta$-hyperbolic if for every geodesic triangle $T$, any side of $T$ is contained in a $\delta$-neighborhood of the union of the other two sides. A graph is chordal if…

Combinatorics · Mathematics 2015-05-22 A. Martínez-Pérez

In this paper, we give a new lifting construction of "hyperbolic" type of strongly regular Cayley graphs. Also we give new constructions of strongly regular Cayley graphs over the additive groups of finite fields based on partitions of…

Combinatorics · Mathematics 2017-06-20 Koji Momihara , Qing Xiang

A graph is edge-transitive if the natural action of its automorphism group on its edge set is transitive. An automorphism of a graph is semiregular if all of the orbits of the subgroup generated by this automorphism have the same length.…

We study endomorphism algebras of 2-term silting complexes in derived categories of hereditary finite dimensional algebras, or more generally of $\mathop{\rm Ext}\nolimits$-finite hereditary abelian categories. Module categories of such…

Representation Theory · Mathematics 2016-09-02 Aslak Bakke Buan , Yu Zhou

We study analytic properties of graph product of finite groups with a hyperbolic defining graph. This is done by studying dynamics on the Bowditch compactification of the extension graph, or the crossing graph, of graph product. In…

Group Theory · Mathematics 2024-12-25 Koichi Oyakawa

Hypergraphs are structures that can be decomposed or described; in other words they are recursively countable. Here, we get exact and asymptotic enumeration results on hypergraphs by means of exponential generating functions. The number of…

Discrete Mathematics · Computer Science 2008-06-20 Tsiriniaina Andriamampianina

We present a technique for the enumeration of all isotopically distinct ways of tiling a hyperbolic surface of finite genus, possibly nonorientable and with punctures and boundary. This provides a generalization of the enumeration of…

Geometric Topology · Mathematics 2020-08-17 Benedikt Kolbe , Myfanwy E. Evans

This article emphasizes an extension of the study of metric and par- tition dimension to hypergraphs. We give a sharp lower bounds for the metric and partition dimension of hypergraphs in general and give exact values under specified…

Combinatorics · Mathematics 2024-06-18 Imran Javaid , Azeem Haider , Muhammad Salman , Sadaf Mehtab

We study analysis over infinite dimensional manifolds consisted by sequences of almost K\"ahler manifolds. In particular we develop moduli theory of pseudo holomorphic curves into the spaces with high symmetry. As applications, we study…

Symplectic Geometry · Mathematics 2017-11-08 Tsuyoshi Kato

We determine the structure of automorphism groups of finite graphs of bounded Hadwiger number. Our proof includes a structural analysis of finite edge-transitive graphs. In particular, we show that for connected, $K_{h+1}$-minor-free,…

Combinatorics · Mathematics 2025-09-24 Martin Grohe , Pascal Schweitzer , Daniel Wiebking

We recall and define various kinds of supersingular $\ell$-isogeny graphs and precise graph isomorphism with a corresponding quaternion $\ell$-ideal graph. In particular, we introduce the notion of double-orientations on supersingular…

Number Theory · Mathematics 2025-10-20 Do Eon Cha , Imin Chen

We develop an explicit geometric construction of automorphisms of finite fields arising from isogeny cycles. Let $k$ be a finite field, $E/k$ an elliptic curve, and $\ell$ an integer coprime to $\mathrm{char}(k)$. Let $\mathfrak{h}$ be an…

Number Theory · Mathematics 2026-03-23 Kéva Djambaé

A projective manifold $M$ is algebraically hyperbolic if there exists a positive constant $A$ such that the degree of any curve of genus $g$ on $M$ is bounded from above by $A(g-1)$. A classical result is that Kobayashi hyperbolicity…

Algebraic Geometry · Mathematics 2021-09-20 Fedor Bogomolov , Ljudmila Kamenova , Misha Verbitsky

Let $H$ be a complete $r$-uniform hypergraph such that two vertices are marked in each edge as its `boundary' vertices. A linear ordering of the vertex set of $H$ is called an {\em agreeing linear order}, provided all vertices of each edge…

Combinatorics · Mathematics 2023-01-19 Csaba Biró , Jenő Lehel , Géza Tóth

We prove that the sublinearly Morse boundary of every known cubulated group continuously injects in the Gromov boundary of a certain hyperbolic graph. We also show that for all CAT(0) cube complexes, convergence to sublinearly Morse…

Geometric Topology · Mathematics 2021-01-05 Merlin Incerti-Medici , Abdul Zalloum

A smooth curve in the real projective plane is hyperbolic if its ovals are maximally nested. By the Helton-Vinnikov Theorem, any such curve admits a definite symmetric determinantal representation. We use polynomial homotopy continuation to…

Algebraic Geometry · Mathematics 2016-07-05 Anton Leykin , Daniel Plaumann

Hypergraphs are mathematical models for many problems in data sciences. In recent decades, the topological properties of hypergraphs have been studied and various kinds of (co)homologies have been constructed (cf. [3, 4, 12]). In this…

Algebraic Topology · Mathematics 2018-03-15 Stephane Bressan , Jingyan Li , Shiquan Ren , Jie Wu

Given two graphs $G$ and $H$, we say that $G$ contains $H$ as an induced minor if a graph isomorphic to $H$ can be obtained from $G$ by a sequence of vertex deletions and edge contractions. We study the complexity of Graph Isomorphism on…

Discrete Mathematics · Computer Science 2016-05-30 Rémy Belmonte , Yota Otachi , Pascal Schweitzer

A graph is locally chordal if each of its small-radius balls is chordal. In an earlier work [AKK25], the authors and Kobler proved that locally chordal graphs can be characterized by having chordal local covers, by forbidding short cycles…

Combinatorics · Mathematics 2025-12-23 Tara Abrishami , Paul Knappe

The class of Euclidean unit disk graphs is one of the most fundamental and well-studied graph classes with underlying geometry. In this paper, we identify this class as a special case in the broader class of hyperbolic unit disk graphs and…

Data Structures and Algorithms · Computer Science 2022-12-16 Thomas Bläsius , Tobias Friedrich , Maximilian Katzmann , Daniel Stephan