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Different group structures which underline the integrable systems are considered. In some cases, the quantization of the integrable system can be provided with substituting groups by their quantum counterparts. However, some other group…

High Energy Physics - Theory · Physics 2007-05-23 A. Mironov

Can we do a topological study of various classes of normal subgroups endowed with a hull-kernel-type topology? In this paper, we have provided an answer to this question. We have introduced as well a new class of normal subgroups called…

Group Theory · Mathematics 2024-08-21 Amartya Goswami

We study groups that can be defined as Polish, pro-countable groups, as non-archimedean groups with an invariant metric or as quasi-countable groups, i.e., closed subdirect products of countable, discrete groups, endowed with the product…

Group Theory · Mathematics 2015-04-16 Maciej Malicki

We give, for some Borel sets of a product of two Polish spaces, including the Borel sets with countable sections, a Hurewicz-like characterization of those which cannot become a transfinite difference of open sets by changing the two Polish…

Logic · Mathematics 2007-10-02 Dominique Lecomte

Utilizing an embedding theorem of Obraztsov we construct groups as described in the title. This provides an affirmative answer to a problem of D. O. Revin. The constructed groups also provide a negative answer to a question highlighted by…

Group Theory · Mathematics 2025-06-23 Samuel M. Corson

We study groups generated by sets of pattern avoiding permutations. In the first part of the paper we prove some general results concerning the structure of such groups. In the second part we carry out a case-by-case analysis of groups…

Combinatorics · Mathematics 2024-07-08 Marilena Barnabei , Niccolò Castronuovo , Matteo Silimbani

This is a survey article on classical groups (over arbitrary division rings) and their geometries.

Group Theory · Mathematics 2007-05-23 Linus Kramer

Let $K$ be an algebraically closed field of characteristic $p\geqslant 0$ and let $W$ be a finite-dimensional $K$-space of dimension greater than or equal to $5.$ In this paper, we give the structure of certain Weyl modules for…

Representation Theory · Mathematics 2017-05-12 Mikaël Cavallin

We present a selection of results contributing to a structure theory of totally disconnected locally compact groups.

Group Theory · Mathematics 2021-10-13 Pierre-Emmanuel Caprace , George A. Willis

A Polish group $G$ is called a group of quasi-invariance or a QI-group, if there exist a locally compact group $X$ and a probability measure $\mu$ on $X$ such that 1) there exists a continuous monomorphism of $G$ to $X$, and 2) for each…

General Topology · Mathematics 2009-10-01 S. S. Gabriyelyan

First we introduce a generalization of symmetric spaces to parabolic geometries. We provide construction of such parabolic geometries starting with classical symmetric spaces and we show that all regular parabolic geometries with smooth…

Differential Geometry · Mathematics 2012-07-30 Jan Gregorovič

We study groups and rings definable in d-minimal expansions of ordered fields. We generalize to such objects some known results from o-minimality. In particular, we prove that we can endow a definable group with a definable topology making…

Logic · Mathematics 2021-07-12 Antongiulio Fornasiero

General framework for Poisson homogeneous spaces of Poisson groups is introduced. Poisson Minkowski spaces are discussed as a particular example.

High Energy Physics - Theory · Physics 2007-05-23 S. Zakrzewski

In this paper we present new examples of simple $p$-local compact groups for all odd primes. We also develop the necessary tools to show saturation, simpleness and the non-realizability as $p$-compact groups or compact Lie groups, which can…

Algebraic Topology · Mathematics 2017-12-07 Alex Gonzalez , Toni Lozano , Albert Ruiz

The aim of this paper is to present the main constructions of the substructures of an almost groupoid and to discuss their basic properties. The definitions and properties concerning these new algebraic constructions extend to almost…

Group Theory · Mathematics 2026-02-06 Mihai Ivan

Concepts and techniques from the theory of G-structures of higher order are applied to the study of certain structures (volume forms, conformal structures, linear connections and projective structures) defined on a pseudo-Riemanniann…

Differential Geometry · Mathematics 2011-10-26 Ignacio Sanchez-Rodriguez

The main aim of this paper is to introduce some examples of non-compact locally compact quantum groups to a non-specialized audience. The major importance of these examples is their simplicity. Other examples as the quantum E(2) group of…

Operator Algebras · Mathematics 2007-05-23 Stefaan Vaes

We show that every non-Archimedean Polish group $P$ is the outer automorphism group of a countable discrete group $G_P$. Moreover, our construction provides a Borel map $f$ from the Effros space of closed subgroups of the permutation group…

Group Theory · Mathematics 2026-05-26 Jean-Luc Rabideau

We present the (Lascar) Galois group of any countable theory as a quotient of a compact Polish group by an $F_\sigma$ normal subgroup: in general, as a topological group, and under NIP, also in terms of Borel cardinality. This allows us to…

Logic · Mathematics 2020-12-15 Krzysztof Krupiński , Tomasz Rzepecki

Real points of Schottky space ${\mathcal S}_{g}$ are in correspondence with extended Kleinian groups $K$ containing, as a normal subgroup, a Schottky group $\Gamma$ of rank $g$ such that $K/\Gamma \cong {\mathbb Z}_{2n}$ for a suitable…

Geometric Topology · Mathematics 2022-03-17 Ruben A. Hidalgo