English
Related papers

Related papers: A New Topological Helly Theorem and some Transvers…

200 papers

Let $A$ denote an affine algebra over an algebraically closed field $k$, with $\dim A=d\geq 3$. In the light of availability of cancellation theorems for stably free modules $P$ with $rank(P)=d-1$ (corank one), we try to implement the…

Commutative Algebra · Mathematics 2026-03-20 Satya Mandal

For a metric space $(X,d)$, Beer, Naimpally, and Rodriguez-Lopez in ([17]) proposed a unified approach to explore set convergences via uniform convergence of distance functionals on members of an arbitrary family $\mathcal{S}$ of subsets of…

General Topology · Mathematics 2024-07-24 Yogesh Agarwal , Varun Jindal

It is proved that the continuum hypothesis implies the existence of a group M containing a nonalgebraic unconditionally closed set, i.e., a set which is closed in any Hausdorff group topology on M but is not an intersection of finite unions…

Group Theory · Mathematics 2007-05-23 Ol'ga V. Sipacheva

Let $N$ be a finite set and $\mathcal{F}$, an intersection-closed family of subsets. Frankl conjectured that there always exists an element in $N$ which is contained in at most half the number of sets in $\mathcal{F}$ unless $\mathcal{F}…

Combinatorics · Mathematics 2025-01-08 Rainer Schrader

We prove that Ad-semisimple conjugacy classes in a connected Lie group $G$ are closed embedded submanifolds of $G$. We also prove that if $\alpha:H\to G$ is a homomorphism of connected Lie groups such that the kernel of $\alpha$ is discrete…

Group Theory · Mathematics 2007-05-23 Jinpeng An

We give a Hilton-Milner Theorem for the $r$-independent sets in the graph that is the union of copies of $K_k$. That is, we determine the maximum intersecting families of $r$-independent sets in this graph, subject to the condition that the…

Combinatorics · Mathematics 2025-11-25 Karen Gunderson , Karen Meagher , Joy Morris , Venkata Raghu Tej Pantangi

For an integer $d \geq 2$, a family $\mathcal{F}$ of sets is $\textit{$d$-wise intersecting}$ if for any distinct sets $A_1,A_2,\dots,A_d \in \mathcal{F}$, $A_1 \cap A_2 \cap \dots \cap A_d \neq \emptyset$, and $\textit{non-trivial}$ if…

Combinatorics · Mathematics 2019-11-05 Jason O'Neill , Jacques Verstraete

Given a family of sets on the plane, we say that the family is intersecting if for any two sets from the family their interiors intersect. In this paper, we study intersecting families of triangles with vertices in a given set of points. In…

Combinatorics · Mathematics 2021-02-19 Peter Frankl , Andreas Holmsen , Andrey Kupavskii

There exists a function f: N -> N such that for every positive integer d, every quasi-finite field K and every projective hypersurface X of degree d and dimension at least f(d), the set X(K) is non-empty. This is a special case of a more…

Number Theory · Mathematics 2008-02-27 Michael Larsen , Bo-Hae Im

In this paper, we derive a tight upper bound for the size of an intersecting $k$-Sperner family of subspaces of the $n$-dimensional vector space $\mathbb{F}_{q}^{n}$ over finite field $\mathbb{F}_{q}$ which gives a $q$-analogue of the…

Combinatorics · Mathematics 2024-05-01 Jiuqiang Liu , Guihai Yu , Lihua Feng , Yongtao Li

We prove that every complete non-compact manifold of finite volume contains a (possibly non-compact) minimal hypersurface of finite volume. The main tool is the following result of independent interest: if a region $U$ can be swept out by a…

Differential Geometry · Mathematics 2019-08-27 Gregory R. Chambers , Yevgeny Liokumovich

Let $X$ be a paracompact space, let $G$ be a finite group acting freely on $X$ and let $H$ a cyclic subgroup of $G$ of prime order $p$. Let $f:X\rightarrow M$ be a continuous map where $M$ is a connected $m$-manifold (orientable if $p>2$)…

Algebraic Topology · Mathematics 2016-11-01 Denise de Mattos , Edivaldo L. dos Santos , Taciana O. Souza

Let G be a complex reductive algebraic group. We study complete intersections in a spherical homogeneous space G/H defined by a generic collection of sections from G-invariant linear systems. Whenever nonempty, all such complete…

Algebraic Geometry · Mathematics 2015-06-11 Kiumars Kaveh , A. G. Khovanskii

In the paper we introduce a new family of "small" sets which is tightly connected with two well known $\sigma$-ideals: of Haar-null sets and of Haar-meager sets. We define a subset $A$ of a topological group $X$ to be…

General Topology · Mathematics 2021-11-01 Taras Banakh , Eliza Jabłońska

In this note, as a particular case of a more general result, we obtain the following theorem: Let $\Omega\subseteq {\bf R}^n$ be a non-empty bounded open set and let $f:\overline {\Omega}\to {\bf R}^n$ be a continuous function which is…

Analysis of PDEs · Mathematics 2016-02-17 Biagio Ricceri

We prove the existence of infinite dense free sets (in the usual topology) for set mappings on the reals, under reasonable assumptions.

Logic · Mathematics 2016-11-15 Shimon Garti

We find new conditions that the existence of nullity of the curvature tensor of an irreducible homogeneous space $M=G/H$ imposes on the Lie algebra $\mathfrak g$ of $G$ and on the Lie algebra $\tilde{\mathfrak g}$ of the full isometry group…

Differential Geometry · Mathematics 2022-07-06 Antonio J. Di Scala , Carlos E. Olmos , Francisco Vittone

Over any field of characteristic $0$, we prove that the homotopy exact sequence of algebraic fundamental groups for the universal curve with unordered marked points does not split. The same nonsplitting holds for the universal hyperelliptic…

Algebraic Geometry · Mathematics 2025-11-18 Tatsunari Watanabe , Ma Luo

A classical theorem of Hurewicz characterizes spaces with the Hurewicz covering property as those having bounded continuous images in the Baire space. We give a similar characterization for spaces X which have the Hurewicz property…

General Topology · Mathematics 2014-09-02 Boaz Tsaban , Lyubomyr Zdomskyy

We prove that for the functions of the form $g(x) = h(x) + \frac{C}{x+i}$, where $h$ belongs to the continuous Wiener algebra $W_0$, the intersection of the frame set $\mathcal{F}_g$ with every hyperbola $\{\alpha, \beta > 0 \mid…

Functional Analysis · Mathematics 2024-04-02 Aleksei Kulikov
‹ Prev 1 8 9 10 Next ›