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Related papers: On a Van Kampen Theorem for Hawaiian Groups

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In this paper we extend the theory of H-closed extensions of Hausdorff spaces to a class of non-Hausdorff spaces, defined in \cite{B}, called $n$-Hausdorff spaces. The notion of H-closed is generalized to an $n$-H-closed space. Known…

General Topology · Mathematics 2018-08-24 Fortunata Aurora Basile , Maddalena Bonanzinga , Nathan Carlson , Jack Porter

Generalized Haag's theorem has been proved in S O (1, k) invariant quantum field theory. Apart from the above mentioned k+1 variables there can be arbitrary number of additional coordinates including noncommutative ones in the theory. New…

Mathematical Physics · Physics 2011-05-13 K. V. Antipin , Yu. S. Vernov , M. N. Mnatsakanova

We prove that for a fairly large family of HNN extensions \Gamma, the group measure space II_1 factor L^\infty(X) \rtimes \Gamma given by an arbitrary free ergodic probability measure preserving action of \Gamma, has a unique group measure…

Operator Algebras · Mathematics 2012-02-07 Pierre Fima , Stefaan Vaes

We develop a systematic method to describe the moduli space of vacua of four dimensional $\mathcal{N}=2$ class ${\cal S}$ theories including Coulomb branch, Higgs branch and mixed branches. In particular, we determine the Higgs and mixed…

High Energy Physics - Theory · Physics 2015-06-19 Dan Xie , Kazuya Yonekura

In 1933, van Kampen described the fundamental groups of the complements of plane complex projective algebraic curves. Recently, Ch\'eniot-Libgober proved an analogue of this result for higher homotopy groups of the complements of complex…

Algebraic Geometry · Mathematics 2007-05-23 D. Chéniot , C. Eyral

We organize fundamental properties of quasi-Hamiltonian spaces on which a finite group acts, and we apply them to the theory of moduli spaces of flat connections on an oriented compact surface with boundary.

Symplectic Geometry · Mathematics 2025-12-23 Keito Takegoshi

In a recent paper, Colliot-Th\'el\`ene, Parimala and Suresh conjectured that a local-global principle holds for projective homogeneous spaces of connected linear algebraic groups over function fields of p-adic curves. In this paper, we show…

Number Theory · Mathematics 2019-08-02 Zhengyao Wu

We give a criterion for bounding the homological finiteness length of certain HF-groups. This is used in two distinct contexts. Firstly, the homological finiteness length of a non-uniform lattice on a locally finite n-dimensional…

Group Theory · Mathematics 2014-02-26 Giovanni Gandini

Let $M$ be a smooth manifold. We use Chern-Weil theory to study the characteristic classes of principal $G$-bundles built from continuous families of $\pi_{1}(M)$-representations, where $G$ is a compact Lie group. We then relate these…

Algebraic Topology · Mathematics 2025-12-18 Andrew Davis

We attach copies of the circle to points of a countable dense subset $D$ of a separable metric space $X$ and construct an earring space $E(X,D)$. We show that the fundamental group of $E(X,D)$ is isomorphic to a subgroup of the Hawaiian…

Geometric Topology · Mathematics 2020-01-08 Katsuya Eda

In this paper, we define locally convex vector spaces of weighted vector fields and use them as model spaces for Lie groups of weighted diffeomorphisms on Riemannian manifolds. We prove an easy condition on the weights that ensures that…

Differential Geometry · Mathematics 2016-01-13 Boris Walter

We investigate the existence of an H-space structure on the function space, F_*(X,Y,*), of based maps in the component of the trivial map between two pointed connected CW-complexes X and Y. For that, we introduce the notion of H(n)-space…

Algebraic Topology · Mathematics 2014-10-01 Yves Felix , Daniel Tanre

This article is devoted to the investigation of wrap groups of connected fiber bundles over the fields of real $\bf R$, complex $\bf C$ numbers, the quaternion skew field $\bf H$ and the octonion algebra $\bf O$. Cohomologies of wrap groups…

Algebraic Topology · Mathematics 2010-03-16 S. V. Ludkovsky

Let $F$ be a nonarchimedean local field, and $G$ the group of $F$-points of a c onnected quasisplit reductive group defined on $F$; in this paper, we will study the distributions on $G$ which are invariant by conjugation, and the vector spa…

Group Theory · Mathematics 2007-05-23 Francois Courtes

We survey the theory of locally homogeneous almost-Hermitian spaces. In particular, by using the framework of varying Lie brackets, we write formulas for the curvature of all the Gauduchon connections and we provide explicit examples of…

Differential Geometry · Mathematics 2023-05-03 Daniele Angella , Francesco Pediconi

We consider locally equi-continuous strongly continuous semigroups on locally convex spaces (X,tau). First, we show that if (X,tau) has the property that weak* compact sets of the dual are equi-continuous, then strong continuity of the…

Functional Analysis · Mathematics 2019-09-13 Richard C. Kraaij

The purpose of this paper is to articulate an observation that many interesting type of wavelets (or coherent states) arise from group representations which are not square integrable or vacuum vectors which are not admissible. This extends…

Functional Analysis · Mathematics 2010-05-18 Vladimir V. Kisil

The dimension of the space of SU(n) and translation invariant continuous valuations on $\mathbb{C}^n, n \geq 2$ is computed. For even $n$, this dimension equals $(n^2+3n+10)/2$; for odd $n$ it equals $(n^2+3n+6)/2$. An explicit geometric…

Differential Geometry · Mathematics 2010-05-21 Andreas Bernig

From any two median spaces $X,Y$, we construct a new median space $X \circledast Y$, referred to as the diadem product of $X$ and $Y$, and we show that this construction is compatible with wreath products in the following sense: given two…

Group Theory · Mathematics 2021-01-21 Anthony Genevois

We prove a sharp, quantitative analogue of Helgason's conjecture at the level of distributions: For a semisimple Lie group $G$ of real rank one, Poisson transforms map a Sobolev space on $P\backslash G$ boundedly with closed range to an…

K-Theory and Homology · Mathematics 2026-04-08 Heiko Gimperlein , Magnus Goffeng