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This paper concerns a class of semigroups that arise as products $US$, associated to what we call `action pairs'. Here $U$ and $S$ are subsemigroups of a common monoid and, roughly speaking, $S$ has an action on the monoid completion $U^1$…

Rings and Algebras · Mathematics 2023-09-21 Scott Carson , Igor Dolinka , James East , Victoria Gould , Rida-e Zenab

A formal theory based on a binary operator of directional associative relation is constructed in the article and an understanding of an associative normal form of image constructions is introduced. A model of a commutative semigroup, which…

Computation and Language · Computer Science 2012-01-06 Oleg Bisikalo , Irina Kravchuk

Let us consider a linear control system \Sigma on a connected Lie group G. It is known that the accessibility set A from the identity e is in general not a semigroup. In this article we associate a new algebraic object S to \Sigma which…

Dynamical Systems · Mathematics 2016-07-12 Victor Ayala , Adriano da Silva

Translation association schemes are constructed from actions of finite groups on finite abelian groups satisfying certain natural conditions. It is also shown that the mere existence of maps from finite groups to themselves sending each…

Combinatorics · Mathematics 2011-08-26 Dae San Kim , Hyun Kwang Kim

We generalize a result of Hochman in two simultaneous directions: Instead of realizing an effectively closed $\mathbb{Z}^d$ action as a factor of a subaction of a $\mathbb{Z}^{d+2}$-SFT we realize an action of a finitely generated group…

Dynamical Systems · Mathematics 2019-04-26 Sebastián Barbieri , Mathieu Sablik

We discuss a general framework of monotone skew-product semiflows under a connected group action. In a prior work, a compact connected group $G$-action has been considered on a strongly monotone skew-product semiflow. Here we relax the…

Dynamical Systems · Mathematics 2012-01-30 Feng Cao , Mats Gyllenberg , Yi Wang

The notion of a generalized product, refining that of a (symmetric and smooth) simplicial space is introduced and shown to imply the existence of an algebra of pseudodifferential operators. This encompasses many constructions of such…

Differential Geometry · Mathematics 2024-12-19 Richard B. Melrose

We adopt a new perspective on the tensor product of arbitrary semi-lattices. Our basic construction exploits a description of semi-lattices in terms of bi-extensional Chu spaces associated to a target space defined to be the boolean domain.…

Rings and Algebras · Mathematics 2024-03-05 Eric Buffenoir

In this paper, we give several equivalent characterizations for a category with finite biproducts and the sum operation of arrows, and called categories satisfying these semiadditive $\mathbf{C}\mathbf{Mon}$-categories. This allow us to…

Logic in Computer Science · Computer Science 2025-04-28 Koki Nishizawa , Yusuke Ide , Norihiro Tsumagari

Various kinds of infinitary operations satisfying forms of associativity have been considered in the literature by various authors, including A. Tarski, C. Karp, J. H. Conway, D. Krob, N. Bedon, and C. Rispal. Applications include the…

Group Theory · Mathematics 2026-05-28 Paolo Lipparini

In this paper, using group actions, we introduce a new method for constructing partial geometric designs (sometimes referred to as $1\frac{1}{2}$-designs). Using this new method, we construct several infinite families of partial geometric…

Combinatorics · Mathematics 2019-04-15 Jerod Michel , Qi Wang

We study integrable systems on the semidirect product of a Lie group and its Lie algebra as the representation space of the adjoint action. Regarding the tangent bundle of a Lie group as phase space endowed with this semidirect product Lie…

Mathematical Physics · Physics 2015-06-16 S. Capriotti , H. Montani

A famous conjecture of Graham asserts that every set $A \subseteq \mathbb{Z}_p \setminus \{0\}$ can be ordered so that all partial sums are distinct. Bedert and Kravitz proved that this statement holds whenever $|A| \leq e^{c(\log…

Combinatorics · Mathematics 2025-08-20 Simone Costa , Stefano Della Fiore , Eva R. Engel

Let $G$ be a group and $X$ be a product system over a semigroup $P$. Suppose $G$ has a left action on $P$ and $P$ has a right action on $G$, so that one can form a Zappa-Sz\'ep product $P\bowtie G$. We define a Zappa-Sz\'ep action of $G$ on…

Operator Algebras · Mathematics 2020-12-02 Boyu Li , Dilian Yang

In this work, we introduce the notion of a partial action of a group on a strict monoidal category. We propose, in the context of Monoidal categories, new constructions analogous to those existing for partial group actions over an algebra…

Category Theory · Mathematics 2024-12-18 Eliezer Batista , Felipe Lopes Castro , Mykola Khrypchenko

Gamma-semigroup is introduced as a generalization of semigroups by M. K Sen and Saha. In this paper we describe amalgam of two Gamma-semigroups and discuss the embeddability of this amalgam. Further we obtained a necessary condition for the…

Group Theory · Mathematics 2020-10-30 Smisha M A , P G Romeo

We study the exactness of the reduced crossed product of a semigroup dynamical system and the reduced $C^{*}$-algebra of a product system. We show that for a semigroup dynamical system $(A, P,\alpha)$, under reasonable hypotheses (e.g., $P$…

Operator Algebras · Mathematics 2026-04-07 Md Amir Hossain , S. Sundar

We define and construct a new data structure, the tables, this structure generalizes the (finite) $k$-sets sets of Eilenberg \cite{Ei}, it is versatile (one can vary the letters, the words and the coefficients). We derive from this…

Multiagent Systems · Computer Science 2016-08-16 Cyrille Bertelle , Gérard Henry Edmond Duchamp , Khalaf Khatatneh

We introduce some deformations of the biset category and prove a semisimplicity property. We also consider another group category, called the subgroup category, whose morphisms are subgroups of direct products, the composition being star…

Representation Theory · Mathematics 2020-01-09 Laurence Barker , İsmail Alperen Öğüt

In this paper, we have studied the loops which are the semidirect products of a loop and a group. Also, the cummutant, nuclei and the center of such loops are studied.

Group Theory · Mathematics 2024-06-21 Ratan Lal , Ramjash Gurjar , Vipul Kakkar