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Related papers: Generic groups and the weak amalgamation property

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We give a survey of techniques from quantum group theory which can be used to show that some quantum spaces (objects of the category dual to the category of $\mathrm{C}^*$-algebras) do not admit any quantum group structure. We also provide…

Operator Algebras · Mathematics 2011-04-12 Piotr M. Sołtan

We develop a structure theory of connected solvable spherical subgroups in semisimple algebraic groups. Based on this theory, we obtain an explicit classification of all such subgroups up to conjugation.

Group Theory · Mathematics 2012-01-24 Roman Avdeev

These lecture notes explain the construction and basic properties of the wonderful compactification of a complex semisimple group of adjoint type. An appendix discusses the more general case of a semisimple symmetric space.

Algebraic Geometry · Mathematics 2008-01-04 Sam Evens , Benjamin F Jones

We partially describe equivariant Dirac and generalized complex structures on a homogeneous space $G/K$ by giving equivalent data involving only the Lie algebra. We consider real semisimple adjoint orbits in any semisimple Lie algebra over…

Differential Geometry · Mathematics 2010-08-12 Brett Milburn

The description of the subgroup structure of a non-commutative division ring is the subject of the intensive study in the theory of division rings in particular, and of the theory of skew linear groups in general. This study is still so far…

Rings and Algebras · Mathematics 2020-11-04 Bui Xuan Hai , Huynh Viet Khanh

We generalize the notion of weakly mixing unitary representations to locally compact quantum groups, introducing suitable extensions of all standard characterizations of weak mixing to this setting. These results are used to complement the…

Operator Algebras · Mathematics 2017-07-11 Ami Viselter

Numerical semigroup rings are investigated from the relative viewpoint. It is known that algebraic properties such as singularities of a numerical semigroup ring are properties of a flat numerical semigroup algebra. In this paper, we show…

Commutative Algebra · Mathematics 2021-07-21 I-Chiau Huang , Raheleh Jafari

Over each nontrivial finite group $G$, there exists a finite system of equations having no solutions in larger finite groups but having a solution in a periodic group containing $G$. We prove several similar facts about amenable, orderable,…

Group Theory · Mathematics 2025-03-04 Alexander Buturlakin , Anton Klyachko , Denis Osin

We summarize several results about non-simplicity, solvability and normal structure of finite groups related to the number of conjugacy classes appearing in the product or the power of conjugacy classes. We also collect some problems that…

Group Theory · Mathematics 2024-02-14 Antonio Beltrán , María José Felipe , Carmen Melchor

Working over an arbitrary field, we define compact semisimple 2-categories, and show that every compact semisimple 2-category is equivalent to the 2-category of separable module 1-categories over a finite semisimple tensor 1-category. Then,…

Quantum Algebra · Mathematics 2023-10-27 Thibault D. Décoppet

Let $G$ be a closed highly homogeneous subgroup of $S_{\infty}$ not involving circular orderings. We show that the closure of a conjugacy class from $G$ contains a conjugacy class which is comeagre in it. Furthermore, we show that the…

Logic · Mathematics 2025-04-23 Monika Drzewiecka , Aleksander Ivanov , Bartosz Mokry

We develop some basic results about full amalgamation classes with intrinsic trascendentals. These classes have generics whose models may have finite subsets whose intrinsic closure is not contained in its algebraic closure. We will show…

Logic · Mathematics 2015-12-15 Justin Brody

We study the difference between internal categories and internal groupoids in terms of generalised Mal'tsev properties---the weak Mal'tsev property on the one hand, and $n$-permutability on the other. In the first part of the article we…

Category Theory · Mathematics 2014-08-19 Nelson Martins-Ferreira , Tim Van der Linden

The classification of gradings by abelian groups on finite direct sums of simple finite-dimensional nonassociative algebras over an algebraically closed field is reduced, by means of the use of loop algebras, to the corresponding problem…

Rings and Algebras · Mathematics 2019-04-25 Alejandra S. Córdova-Martínez , Alberto Elduque

We present the notions of positively complete theory and general forms of amalgamation in the framework of positive logic. We explore the fundamental properties of positively complete theories and study the behaviour of companion theories…

Logic · Mathematics 2019-11-15 Mohammed Belkasmi

We investigate whether semigroups with a given property which are also locally embeddable into finite semigroups can be locally embedded into finite semigroups with the same property, obtaining a positive answer for completely simple and…

Group Theory · Mathematics 2025-10-27 Dmitry Kudryavtsev

We study general nilpotent algebras. The results obtained are new even for the classical algebras, such as associative or Lie algebras. We single out certain generic properties of finite-dimensional algebras, mostly over infinite fields.…

Rings and Algebras · Mathematics 2024-06-25 Yuri Bahturin , Alexander Olshanskii

We determine the structure of the semisimple group algebra of certain groups over the rationals and over those finite fields where the Wedderburn decompositions have the least number of simple components. We apply our work to obtain similar…

Representation Theory · Mathematics 2010-09-06 Raul A. Ferraz , Edgar G. Goodaire , Cesar Polcino Milies

We show the existence of and explicitly construct generic polynomials for various groups, over fields of positive characteristic. The methods we develop apply to a broad class of connected linear algebraic groups defined over finite fields…

Number Theory · Mathematics 2016-01-19 Eric Y. Chen , J. T. Ferrara , Liam Mazurowski

In this paper, we consider a question of sum-keeping about a multiplicative subsemigroup and its generator subsets in a semiring, and develop some elementary (collapse) process of the sum-keeping retraction through subsets until one minimal…

Number Theory · Mathematics 2025-04-04 Derong Qiu