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A glimpse of deductive systems in algebra

Dumitru Buşneag, Sergiu Rudeanu (2010)

Open Mathematics

The concept of a deductive system has been intensively studied in algebraic logic, per se and in connection with various types of filters. In this paper we introduce an axiomatization which shows how several resembling theorems that had been separately proved for various algebras of logic can be given unique proofs within this axiomatic framework. We thus recapture theorems already known in the literature, as well as new ones. As a by-product we introduce the class of pre-BCK algebras.

A new look at pointfree metrization theorems

Bernhard Banaschewski, Aleš Pultr (1998)

Commentationes Mathematicae Universitatis Carolinae

We present a unified treatment of pointfree metrization theorems based on an analysis of special properties of bases. It essentially covers all the facts concerning metrization from Engelking [1] which make pointfree sense. With one exception, where the generalization is shown to be false, all the theorems extend to the general pointfree context.

A non commutative generalization of ☆ -autonomous lattices

P. Emanovský, Jiří Rachůnek (2008)

Czechoslovak Mathematical Journal

Pseudo ☆ -autonomous lattices are non-commutative generalizations of ☆ -autonomous lattices. It is proved that the class of pseudo ☆ -autonomous lattices is a variety of algebras which is term equivalent to the class of dualizing residuated lattices. It is shown that the kernels of congruences of pseudo ☆ -autonomous lattices can be described as their normal ideals.

A note on congruence systems of MS-algebras

M. Campercholi, Diego Vaggione (2007)

Mathematica Bohemica

Let L be an MS-algebra with congruence permutable skeleton. We prove that solving a system of congruences ( θ 1 , ... , θ n ; x 1 , ... , x n ) in L can be reduced to solving the restriction of the system to the skeleton of L , plus solving the restrictions of the system to the intervals [ x 1 , x ¯ ¯ 1 ] , ⋯ , [ x n , x ¯ ¯ n ] .

A note on cylindric lattices

Ivo Düntsch (1993)

Banach Center Publications

0. Introduction. Besides being of intrinsic interest, cylindric (semi-) lattices arise naturally from the study of dependencies in relational databases; the polynomials on a cylindric semilattice are closely related to the queries obtainable from project-join mappings on a relational database (cf. [D] for references). This note is intended to initiate the study of these structures, and only a few, rather basic results will be given. Some problems at the end will hopefully stimulate further research....

A Note on Pseudo-Kleene Algebras

Ivan Chajda (2016)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

We introduce the concept of a pseudo-Kleene algebra which is a non-distributive modification of a Kleene algebra introduced by J. A. Kalman [Kalman, J. A.: Lattices with involution. Trans. Amer. Math. Soc. 87 (1958), 485–491.]. Basic properties of pseudo-Kleene algebras are studied. For pseudo-Kleene algebras with a fix-point there are determined subdirectly irreducible members.

A note on Stone join-semilattices

Shriram Nimbhorkar, Anwari Rahemani (2011)

Open Mathematics

Characterizations for a pseudocomplemented modular join-semilattice with 0 and 1 and its ideal lattice to be a Stone lattice are given.

A note on the symmetric difference in lattices.

Eloy Renedo, Enric Trillas, Claudio Alsina (2005)

Mathware and Soft Computing

The paper introduces a definition of symmetric difference in lattices with negation, presents its general properties and studies those that are typical of ortholattices, orthomodular lattices, De Morgan and Boolean algebras.

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