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Some properties of the weak subalgebra lattice of a partial algebra of a fixed type

Konrad Pióro (2002)

Archivum Mathematicum

We investigate, using results from [[p3]], when a given lattice is isomorphic to the weak subalgebra lattice of a partial algebra of a fixed type. First, we reduce this problem to the question when hyperedges of a hypergraph can be directed to a form of directed hypergraph of a fixed type. Secondly, we show that it is enough to consider some special hypergraphs. Finally, translating these results onto the lattice language, we obtain necessary conditions for our algebraic problem, and also, we completely...

Subalgebra extensions of partial monounary algebras

Danica Jakubíková-Studenovská (2006)

Czechoslovak Mathematical Journal

For a subalgebra of a partial monounary algebra 𝒜 we define the quotient partial monounary algebra 𝒜 / . Let , 𝒞 be partial monounary algebras. In this paper we give a construction of all partial monounary algebras 𝒜 such that is a subalgebra of 𝒜 and 𝒞 𝒜 / .

Tensor products of partial algebras.

Miquel Monserrat, Francesc Roselló, Joan Torrens (1992)

Publicacions Matemàtiques

In this paper we introduce the tensor product of partial algebras w.r.t. a quasi-primitive class of partial algebras, and we prove some of its main properties. This construction generalizes the well-known tensor product of total algebras w.r.t. varieties.

The exocenter and type decomposition of a generalized pseudoeffect algebra

David J. Foulis, Silvia Pulmannová, Elena Vinceková (2013)

Discussiones Mathematicae - General Algebra and Applications

We extend the notion of the exocenter of a generalized effect algebra (GEA) to a generalized pseudoeffect algebra (GPEA) and show that elements of the exocenter are in one-to-one correspondence with direct decompositions of the GPEA; thus the exocenter is a generalization of the center of a pseudoeffect algebra (PEA). The exocenter forms a boolean algebra and the central elements of the GPEA correspond to elements of a sublattice of the exocenter which forms a generalized boolean algebra. We extend...

The subalgebra lattice of a finite algebra

Konrad Pióro (2014)

Open Mathematics

The aim of this paper is to characterize pairs (L, A), where L is a finite lattice and A a finite algebra, such that the subalgebra lattice of A is isomorphic to L. Next, necessary and sufficient conditions are found for pairs of finite algebras (of possibly distinct types) to have isomorphic subalgebra lattices. Both of these characterizations are particularly simple in the case of distributive subalgebra lattices. We do not restrict our attention to total algebras only, but we consider the more...

The weak hereditary class of a variety

Wiktor Bartol, Francesc Rosselló (2006)

Czechoslovak Mathematical Journal

We study the weak hereditary class S w ( 𝒦 ) of all weak subalgebras of algebras in a total variety 𝒦 . We establish an algebraic characterization, in the sense of Birkhoff’s HSP theorem, and a syntactical characterization of these classes. We also consider the problem of when such a weak hereditary class is weak equational.

Currently displaying 81 – 100 of 107