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Related papers: Globalization of twisted partial actions

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Given a partial action $\alpha=(A_g,\alpha_g)_{g\in \mathcal{G}}$ of a connected groupoid $\mathcal{G}$ on a ring $A$ and an object $x$ of $\mathcal{G}$, the isotropy group $\mathcal{G}(x)$ acts partially on the ideal $A_x$ of $A$ by the…

Rings and Algebras · Mathematics 2020-11-18 Dirceu Bagio , Antonio Paques , Héctor Pinedo

We develop the notion of Rokhlin dimension for partial actions of finite groups, extending the well-established theory for global systems. The partial setting exhibits phenomena that cannot be expected for global actions, usually stemming…

Operator Algebras · Mathematics 2022-01-25 Fernando Abadie , Eusebio Gardella , Shirly Geffen

We study the globalization of partial actions on sets and topological spaces and of partial coactions on algebras by applying the general theory of globalization for geometric partial comodules, as previously developed by the authors. We…

Rings and Algebras · Mathematics 2022-03-31 Paolo Saracco , Joost Vercruysse

We extend the classical construction by Noether of crossed product algebras, defined by finite Galois field extensions, to cover the case of separable (but not necessarily finite or normal) field extensions. This leads us naturally to…

Rings and Algebras · Mathematics 2020-06-05 Juan Cala , Patrik Nystedt , Héctor Pinedo

In this paper, we first generalize the theorem about the existence of an enveloping action to a partial twisted smash product. Second, we construct a Morita context between the partial twisted smash product and the twisted smash product…

Rings and Algebras · Mathematics 2015-01-05 Shuangjian Guo , Shengxiang Wang

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

For a twisted partial action \Theta of a group G on an (associative non-necessarily unital) algebra A over a commutative unital ring k, the crossed product A X_\Theta G is proved to be associative. Given a G-graded k-algebra B =…

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

We introduce (continuous) partial category actions on sets (topological spaces) and show that each such action admits a universal globalization. Thereby, we obtain a simultaneous generalization of corresponding results for groups, by…

Rings and Algebras · Mathematics 2017-04-26 Patrik Nystedt

We introduce the concept of an extension of a semilattice of groups $A$ by a group $G$ and describe all the extensions of this type which are equivalent to the crossed products $A*_\Theta G$ by twisted partial actions $\Theta$ of $G$ on…

Group Theory · Mathematics 2017-08-08 Mikhailo Dokuchaev , Mykola Khrypchenko

We show that any continuous partial action on a topological space has a unique enveloping action, i.e. it is the restriction of a global action. In the case of C^*-algebras we prove that any partial action has an enveloping action up to…

Operator Algebras · Mathematics 2018-03-28 Fernando Abadie

A generalization of G-sets, called partial G-sets, are the sets that admit an action of partial maps on their subsets. Partial actions are a powerful tool to generalize many results of group actions. These generalizations are obtained by…

Rings and Algebras · Mathematics 2016-02-01 Ram Parkash Sharma , Meenakshi

We introduce partial semigroupoid actions on sets and demonstrate that each such action admits universal globalization. Our construction extends the universal globalization for partial category actions given by P. Nystedt (Lundstr\"om) and…

Rings and Algebras · Mathematics 2025-12-11 Rafael Haag Petasny , Thaísa Tamusiunas

We generalize Exel's notion of partial group action to monoids. For partial monoid actions that can be defined by means of suitably well-behaved systems of generators and relations, we employ classical rewriting theory in order to describe…

General Topology · Mathematics 2007-05-23 Michael Megrelishvili , Lutz Schroeder

We study the problem of constructing a globalization for partial actions on *-algebras, C*-algebras and Hilbert modules. For the first ones we give a necessary condition for the existence of a globalization and we prove this conditions is…

Operator Algebras · Mathematics 2021-08-12 Damián Ferraro

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

We extend the concept of a partial group action to non-associative algebras in a variety \(\mathcal{V}(I)\), solve the globalization problem within \(\mathcal{V}(I)\) and examine its universal property. It is achieved using what we call the…

Rings and Algebras · Mathematics 2026-04-24 Mikhailo Dokuchaev , Emmanuel Jerez , José L. Vilca-Rodríguez

Let $\big((A^{(i)}, G, \alpha^{(i)}), \phi_i\big)_{i \in \mathbb{N}}$ be an inductive sequence of partial dynamical systems. We prove the existence of an induced partial action $\alpha$ of $G$ on the inductive limit $A=\varinjlim A^{(i)}$.…

Operator Algebras · Mathematics 2025-12-03 Md Amir Hossain

We survey the extensions of a group by a group using crossed products instead of exact sequences of groups. The approach has various advantages, one of them being that the crossed product is an universal object. Several new applications are…

Group Theory · Mathematics 2014-03-18 A. L. Agore , G. Militaru

In this article, we consider a twisted partial action $\alpha$ of a group $G$ on a ring $R$ and it is associated partial crossed product $R*_{\alpha}^wG$. We study necessary and sufficient conditions for the commutativity and simplicity of…

Rings and Algebras · Mathematics 2013-06-25 Alexandre Baraviera , Wagner Cortes , Marlon Soares

We prove that a partial action is amenable if and only if so is its Morita enveloping action. As applications we prove that any partial representation of a discrete group is positive definite, and we extend a result of Zeller-Meier…

Operator Algebras · Mathematics 2009-06-09 Fernando Abadie , Laura Martí Pérez