Results 31 to 40 of about 15,000 (228)
Semigroup Forum, 2009 A semigroup algebra \(kS\) admits a total ordering if and only if the field \(k\) is formally real and \(S\) is a cancellative orderable semigroup. The case of \(*\)-orderability of \(kS\) is much harder. The notion of a \(*\)-ordering has been extended from division rings to general noncommutative rings in a series of papers by \textit{M.
Klep, Igor, Moravec, Primož
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On the K-theory of crossed products by automorphic semigroup actions [PDF]
, 2012 Let P be a semigroup that admits an embedding into a group G. Assume that the embedding satisfies a certain Toeplitz condition and that the Baum-Connes conjecture holds for G.
Cuntz, Joachim +2 more
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NORMALLY ORDERED SEMIGROUPS [PDF]
Glasgow Mathematical Journal, 2008 AbstractIn this paper we introduce the notion of normally ordered block-group as a natural extension of the notion of normally ordered inverse semigroup considered previously by the author. We prove that the classNOSof all normally ordered block-groups forms a pseudovariety of semigroups and, by using the Munn representation of a block-group, we deduce
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On C-ideals and the basis of an ordered semigroup
AIMS Mathematics, 2020 In this paper, we characterize ordered semigroups containing the greatest ideal and give the conditions of the greatest ideal being a C-ideal in an ordered semigroup.
Ze Gu, Xiang-Yun Xie, Jian Tang
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On an equivalence between regular ordered Γ-semigroups and regular ordered semigroups
Open Mathematics, 2020 In this paper, we develop a technique which enables us to obtain several results from the theory of Γ-semigroups as logical implications of their semigroup theoretical analogues.
Çullhaj Fabiana, Krakulli Anjeza
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Zappa-Sz\'ep products of semigroups and their C*-algebras [PDF]
, 2014 Zappa-Sz\'ep products of semigroups encompass both the self-similar group actions of Nekrashevych and the quasi-lattice-ordered groups of Nica. We use Li's construction of semigroup $C^*$-algebras to associate a $C^*$-algebra to Zappa-Sz\'ep products and
Brownlowe, Nathan +3 more
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Ideals and Green's relations in ordered semigroups
International Journal of Mathematics and Mathematical Sciences, 2006 Exactly as in semigroups, Green's relations play an important role in the theory of ordered semigroups—especially for decompositions of such semigroups.
Niovi Kehayopulu
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Identities in the Algebra of Partial Maps [PDF]
, 2006 We consider the identities of a variety of semigroup-related algebras modelling the algebra of partial maps. We show that the identities are intimately related to a weak semigroup deductive system and we show that the equational theory is decidable.
Jackson, Marcel, Stokes, Tim E.
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Partial Orders on Transformation Semigroups [PDF]
Monatshefte f�r Mathematik, 2003 Denote by \(P(X)\) the semigroup, under composition, of all partial transformations of the set \(X\). Denote by \(\text{dom\,}\alpha\) the domain of \(\alpha\in P(X)\) and denote its range by \(\text{ran\,}\alpha\). Define a partial order \(\leq\) on \(P(X)\) by \(\alpha\leq\beta\) if \(\alpha=\gamma\beta=\beta\mu\) and \(\alpha=\alpha\mu\) for some \(\
Smith, M. Paula Marques, Sullivan, R. P.
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AIMS Mathematics, 2023 An element $ x $ in a semigroup is said to be regular if there exists an element $ y $ in the semigroup such that $ x = xyx $. The element $ y $ is said to be a regular part of $ x $.
Nuttawoot Nupo , Sayan Panma
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