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Lattice theoretical generalizations of some classical linear algebra results are formulated. A vector space is replaced by its subspace lattice and a linear map is replaced by the induced lattice map. This map is a complete join…

Rings and Algebras · Mathematics 2007-05-23 Jeno Szigeti

In this announcement we generalize the Markov-Kakutani fixed point theorem for abelian semi-groups of affine transformations extending it on some class of non-commutative semi-groups. As an interesting example we apply it obtaining a…

Functional Analysis · Mathematics 2007-05-23 Jaroslaw Wawrzycki

We introduce and study $\alpha$-embedded sets and apply them to generalize the Kuratowski Extension Theorem.

General Topology · Mathematics 2014-07-24 Olena Karlova

We introduce a generalization of representations of quivers that contains also representations of posets, vectorspace problems and other matrix problems. Many examples, some of which are given in the paper, show that the language of marked…

Representation Theory · Mathematics 2007-05-23 A. V. Roiter

The inclusion relation between simple objects in the plane may be used to define geometric set systems, or hypergraphs. Properties of various types of colorings of these hypergraphs have been the subject of recent investigations, with…

Computational Geometry · Computer Science 2015-03-17 Jean Cardinal , Matias Korman

We develop a theory of $\times$-homotopy, fundamental groupoids and covering spaces that apply to non-simple graphs, generalizing existing results for simple graphs. We prove that $\times$-homotopies from finite graphs can be decomposed…

Combinatorics · Mathematics 2026-03-17 Tien Chih , Laura Scull

Van der Waerden's (VDW) colouring theorem in combinatoric number theory [1] has scope for physical applications.The solution of the two colour case has enabled the construction of an explicit mapping of an infinite, one dimensional…

Condensed Matter · Physics 2007-05-23 Debashis Gangopadhyay , Ranjan Chaudhury

We consider several generalizations of the classical $\gamma$-positivity of Eulerian polynomials (and their derangement analogues) using generating functions and combinatorial theory of continued fractions. For the symmetric group, we prove…

Combinatorics · Mathematics 2022-03-22 Heesung Shin , Jiang Zeng

Some important properties of the chromatic polynomial also hold for any polynomial set map satisfying p_S(x+y)=\sum_{T\uplus U=S}p_T(x)p_U(y). Using umbral calculus, we give a formula for the expansion of such a set map in terms of any…

Combinatorics · Mathematics 2007-07-06 Gus Wiseman

We study the existence of a natural `linearisation' process for generalised connections on an affine bundle. It is shown that this leads to an affine generalised connection over a prolonged bundle, which is the analogue of what is called a…

Differential Geometry · Mathematics 2009-11-10 Tom Mestdag , Willy Sarlet

The concept of generalised (in the sense of Colombeau) connection on a principal fibre bundle is introduced. This definition is then used to extend results concerning the geometry of principal fibre bundles to those that only have a…

Functional Analysis · Mathematics 2016-09-07 Michael Kunzinger , Roland Steinbauer , James A. Vickers

In [31,32,33] the Gauss-Bonnet formulas for coherent tangent bundles over compact oriented surfaces (without boundary) were proved. We establish the Gauss-Bonnet theorem for coherent tangent bundles over compact oriented surfaces with…

Differential Geometry · Mathematics 2020-05-12 Wojciech Domitrz , Michał Zwierzyński

The paper is devoted to a generalized and simplified version of author's approach to covering theorems in bounded cohomology theory. The amenability assumptions are replaced by weaker and more natural acyclicity assumprions. In the case of…

Algebraic Topology · Mathematics 2020-12-16 Nikolai V. Ivanov

We give two generalizations of Kac's Theorem on representations of quivers. One is to representations of equipped graphs by relations, in the sense of Gelfand and Ponomarev. The other is to representations of quivers in which certain of the…

Representation Theory · Mathematics 2011-09-12 William Crawley-Boevey

We give a proof of Gabber's presentation lemma for finite fields. We use ideas from Poonen's proof of Bertini's theorem to prove this lemma in the special case of open subsets of the affine plane. We then reduce the case of general smooth…

Algebraic Geometry · Mathematics 2018-07-04 Amit Hogadi , Girish Kulkarni

Zalcman's Lemma makes significant applications in normal families, complex dynamics and related problems in complex analysis. In the present paper, we are devoted to generalizing the classical Zalcman's lemma to complex Lie groups by means…

Complex Variables · Mathematics 2025-12-09 Xianjing Dong , Yanda Lv

We extend the fundamental normality test due to Carath\'eodory in the sense of shared functions.

Complex Variables · Mathematics 2010-10-25 Jürgen Grahl , Shahar Nevo

We prove multiple generalizations of Fan's combinatorial labeling result for sphere triangulations. This can be seen as a comprehensive extension of the Borsuk--Ulam theorem. In typical applications, the Borsuk--Ulam theorem gives…

Combinatorics · Mathematics 2025-09-10 Florian Frick , Zoe Wellner

We prove two general decomposition theorems for fixed-point invariants: one for the Lefschetz number and one for the Reidemeister trace. These theorems imply the familiar additivity results for these invariants. Moreover, the proofs of…

Algebraic Topology · Mathematics 2017-09-28 Kate Ponto , Michael Shulman

We present a streamlined proof of K. Ball's symmetric plank theorem in $\mathbb{R}^d$, which solves the affine plank problem raised by Th. Bang for symmetric convex bodies.

Metric Geometry · Mathematics 2022-04-12 Gergely Ambrus