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Related papers: New Short Proofs to Some Stability Theorems

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We prove a new, efficient version of the hypergraph container theorems that is suited for hypergraphs with large uniformities. The main novelty is a refined approach to constructing containers that employs simple ideas from high-dimensional…

Combinatorics · Mathematics 2020-12-11 József Balogh , Wojciech Samotij

For a graph $H$, the {\em extremal number} $ex(n,H)$ is the maximum number of edges in a graph of order $n$ not containing a subgraph isomorphic to $H$. Let $\delta(H)>0$ and $\Delta(H)$ denote the minimum degree and maximum degree of $H$,…

Combinatorics · Mathematics 2014-04-07 Noga Alon , Raphael Yuster

In this note, we establish Andr\'{a}sfai--Erd\H{o}s--S\'{o}s-type stability theorems for two generalized Tur\'{a}n problems involving odd cycles, both of which are extensions of the Erd\H{o}s Pentagon Problem. Our results strengthen…

Combinatorics · Mathematics 2024-09-19 Zian Chen , Jianfeng Hou , Caiyun Hu , Xizhi Liu

A graph $X$ is said to be unstable if the direct product $X\times K_2$ (also called the canonical double cover of $X$) has automorphisms that do not come from automorphisms of its factors $X$ and $K_2$. It is non-trivially unstable if it is…

Combinatorics · Mathematics 2022-10-28 Ademir Hujdurović , Đorđe Mitrović

We study Tur\'an-type extremal problems for distance graphs, motivated by work of Csikv\'ari, Bollob\'as, Tyomkyn, and Uzzell. We determine the maximum number of vertex pairs at distance three in an $n$-vertex graph with no triangle formed…

Combinatorics · Mathematics 2026-05-01 Zhen He , Nika Salia , Casey Tompkins , Xiutao Zhu

The Deligne-Mumford stable reduction theorem asserts that for a family of stable curves over the punctured disk, after a finite base change, the family can be completed in a unique way to a family of stable curves over the disk. In this…

Algebraic Geometry · Mathematics 2021-04-26 Sebastian Casalaina-Martin

Answering questions of Y. Rabinovich, we prove "stability" versions of upper bounds on maximal independent set counts in graphs under various restrictions. Roughly these say that being close to the maximum implies existence of a large…

Combinatorics · Mathematics 2018-08-22 Jeff Kahn , Jinyoung Park

We introduce a strong notion of quasiconvexity in finitely generated groups, which we call stability. Stability agrees with quasiconvexity in hyperbolic groups and is preserved under quasi-isometry for finitely generated groups. We show…

Geometric Topology · Mathematics 2015-11-25 Matthew Gentry Durham , Samuel J. Taylor

In this paper, we will prove a very general result of stability for perturbations of linear integrable Hamiltonian systems, and we will construct an example of instability showing that both our result and our example are optimal. Moreover,…

Dynamical Systems · Mathematics 2015-05-28 Abed Bounemoura

The rigidity theorems of Llarull and Marques-Neves, which show two different ways scalar curvature can characterize the sphere, have associated stability conjectures. Here we produce the first examples related to these stability…

Differential Geometry · Mathematics 2023-03-10 Paul Sweeney

This paper proves that the 2-Calabi-Yau triangulated category associated with the preprojective algebra of an affine or hyperbolic graph admits many real variations of stability conditions, in the sense of Anno, Bezrukavnikov, and…

Representation Theory · Mathematics 2024-07-11 Samuel Lewis

We illustrate how to extend the concept of structural stability through applying it to the front propagation speed selection problem. This consideration leads us to a renormalization group study of the problem. The study illustrates two…

Condensed Matter · Physics 2009-10-22 Lin-Yuan Chen , Nigel Goldenfeld , Y. Oono , Glenn Paquette

We prove some results on the border of Ramsey theory (finite partition calculus) and model theory. Also a beginning of classification theory of finite models in undertaken.

Logic · Mathematics 2016-09-06 Doug Ensley , Rami Grossberg

In the paper we have developed a theory of stability preserving structural transformations of systems of second-order ordinary differential equations (ODEs), i.e., the transformations which preserve the property of Lyapunov stability. The…

Dynamical Systems · Mathematics 2012-04-10 Volodymyr Makarov , Denis Dragunov

We show the short-time existence and nonlinear stability of vortex sheets for the nonisentropic compressible Euler equations in two spatial dimensions, based on the weakly linear stability result of Morando--Trebeschi (2008) [20]. The…

Analysis of PDEs · Mathematics 2020-09-24 Alessandro Morando , Paola Trebeschi , Tao Wang

This paper presents finite-time and fixed-time stabilization results for inhomogeneous abstract evolution problems, extending existing theories. We prove well-posedness for strong and weak solutions, and estimate upper bounds for settling…

Systems and Control · Electrical Eng. & Systems 2026-02-12 Moussa Labbadi , Christophe Roman , Yacine Chitour

A cornerstone of extremal graph theory due to Erd\H{o}s and Stone states that the edge density which guarantees a fixed graph $F$ as subgraph also asymptotically guarantees a blow-up of $F$ as subgraph. It is natural to ask whether this…

Combinatorics · Mathematics 2026-04-01 Richard Lang , Nicolás Sanhueza-Matamala

We introduce the notion of sink-stable sets of a digraph and prove a min-max formula for the maximum cardinality of the union of k sink-stable sets. The results imply a recent min-max theorem of Abeledo and Atkinson on the Clar number of…

Combinatorics · Mathematics 2012-05-29 Dóra Erdős , András Frank , Krisztián Kun

The Tur\'an number $\ex(n,H)$ is the maximum number of edges that an $n$-vertex $H$-free graph can have. The suspension $\widehat{H}$ is obtained from $H$ by adding a new vertex which is adjacent to all vertices of $H$ and a tree is…

Combinatorics · Mathematics 2025-03-10 Xiutao Zhu , Xiaolin Wang , Yanbo Zhang , Fangfang Zhang

We deal with the systematic development of stability for the context of approximate elementary submodels of a monster metric space, which is not far, but still very distinct from the first order case. In particular we prove the analogue of…

Logic · Mathematics 2007-05-23 Saharon Shelah , Alex Usvyatsov