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Related papers: A new semidirect product for association schemes

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Semibiproducts of monoids are introduced here as a common generalization to biproducts (of abelian groups) and to semidirect products (of groups) for exploring a wide class of monoid extensions. More generally, abstract semibiproducts exist…

Category Theory · Mathematics 2022-05-03 Nelson Martins-Ferreira

Given a partial action \alpha of a group G on an associative algebra A we consider the crossed product A x_\alpha G. Using the algebras of multipliers of ideals of A we prove that A x_\alpha G is associative, provided that all ideals of A…

Rings and Algebras · Mathematics 2010-03-16 M. Dokuchaev , R. Exel

The tendency of semidefinite programs to compose perfectly under product has been exploited many times in complexity theory: for example, by Lovasz to determine the Shannon capacity of the pentagon; to show a direct sum theorem for…

Computational Complexity · Computer Science 2008-05-01 Troy Lee , Rajat Mittal

This paper aims to introduce a more general definition of quasirandom groups and generalize several well-known results in the literature in this new setting. More precisely, let $G$ be a semi-direct product of groups and $X\subseteq G$, we…

Combinatorics · Mathematics 2023-08-28 Thang Pham , Boqing Xue

The aim of the article is to study the extension theory of gyrogroups under certain conditions. Consequently, we see that there is an equivalence between the category GEXT of group-gyro extensions and the category GFAC of group-gyro factor…

Group Theory · Mathematics 2021-11-11 Akshay Kumar , Mani Shankar Pandey , Seema Kushwaha , Sumit Kumar Upadhyay

We study automaton structures, i.e. groups, monoids and semigroups generated by an automaton, which, in this context, means a deterministic finite-state letter-to-letter transducer. Instead of considering only complete automata, we…

Formal Languages and Automata Theory · Computer Science 2020-07-17 Daniele D'Angeli , Emanuele Rodaro , Jan Philipp Wächter

Let $G$ be a group which is the semidirect product of a normal subgroup $N$ and a subgroup $T$, and let $M$ be a $G$-module with not necessarily trivial $G$-action. Then we embed the simultaneous restriction map $res=(res^G_N,res^G_T)^t :…

Group Theory · Mathematics 2007-07-03 Manfred Hartl , Sébastien Leroy

We study unitary representations of semidirect products of a compact quantum group with a finite group. We give a classification of all irreducible unitary representations, a description of the conjugate representation of irreducible…

Operator Algebras · Mathematics 2020-09-28 Hua Wang

In the context of Hecke algebras of complex reflection groups, we prove that the generalized Hecke algebras of normalizers of parabolic subgroups are semidirect products, under suitable conditions on the parameters involved in their…

Representation Theory · Mathematics 2020-10-23 Thomas Gobet , Ivan Marin

This paper shows that the semi-direct product construction for $G$-operads and the levelwise Borel construction for $G$-cooperads are intertwined by the topological operadic bar construction. En route we give a generalization of the bar…

Algebraic Topology · Mathematics 2019-08-21 Benjamin C. Ward

In this work, we provide a way of constructing new semiorthogonal decompositions using metric techniques (\`a la Neeman). Given a semiorthogonal decomposition on a category with a special kind of metric, which we call a compressible metric,…

Algebraic Geometry · Mathematics 2025-04-17 Kabeer Manali Rahul

Self-similar symmetric $\alpha$-stable, $\alpha\in(0,2)$, mixed moving averages can be related to nonsingular flows. By using this relation and the structure of the underlying flows, one can decompose self-similar mixed moving averages into…

Probability · Mathematics 2007-05-23 Vladas Pipiras , Murad S. Taqqu

We study the (restricted) Nagata product construction, which produces a partially ordered semigroup from a bimodule consisting of a partially ordered semigroup acting on a (pointed) join semilattice. A canonical example of such a bimodule…

Logic · Mathematics 2025-05-19 Adam Přenosil , Constantine Tsinakis

In this paper we present the construction of explicit quasi-isomorphisms that compute the cyclic homology and periodic cyclic homology of crossed-product algebras associated with (discrete) group actions. In the first part we deal with…

K-Theory and Homology · Mathematics 2017-09-26 Raphael Ponge

Association schemes on triples (ASTs) are 3-dimensional analogues of classical association schemes. If a group acts two-transitively on a set, the orbits of the action induced on the triple Cartesian product of that set yields an AST. By…

Combinatorics · Mathematics 2023-08-22 Dom Vito A. Briones

We introduce a generalization of the product expansion of a finite semigroup. As an application, we provide an alternative proof of the decidability of pointlike sets for pseudovarieties consisting of semigroups whose subgroups all belong…

Group Theory · Mathematics 2021-10-25 Karsten Henckell , Samuel Herman

Classical finite association schemes lead to a finite-dimensional algebras which are generated by finitely many stochastic matrices. Moreover, there exist associated finite hypergroups. The notion of classical discrete association schemes…

Group Theory · Mathematics 2019-05-21 Michael Voit

We study compatible actions (introduced by Brown and Loday in their work on the non-abelian tensor product of groups) in the category of Lie algebras over a fixed ring. We describe the Peiffer product via a new diagrammatic approach, which…

Rings and Algebras · Mathematics 2019-06-11 Davide di Micco

It is well known that finite commutative association schemes in the sense of the monograph of Bannai and Ito lead to finite commutative hypergroups with positive dual convolutions and even dual hypergroup structures. In this paper we…

Group Theory · Mathematics 2017-08-04 Michael Voit

The binary products of right, left or double division in semigroups that are semilattices of groups give interesting groupoid structures that are in one to one correspondence with semigroups that are semilattices of groups. This work is…

Rings and Algebras · Mathematics 2019-04-03 R. A. R. Monzo