(Skew) Filters in Residuated Skew Lattices

In this paper, we show the relationship between (skew) deductive system and (skew) filter in residuated skew lattices. It is shown that if a residuated skew lattice is conormal, then any skew deductive system is a skew filter under a condition and deductive system and skew deductive system are equivalent under some conditions too. It is investigated that in branchwise residuated skew lattice, filter, deductive system and skew deductive system are equivalent. We define some types of prime (skew) filters in residuated skew lattices and show the relationship between prime (skew) filters and residuated skew chaines. It is proved that in prelinear residuated skew lattice any proper filter can be extended to a maximal, prime filter of type (I). The notion of the radical of a filter is defined and several characterizations of the radical of a filter are given. We show that in non conormal prelinear residuated skew lattice with element 0, infinitesimal elements are equal to intersection of all the maximal filters

The Reticulation of a Universal Algebra

The reticulation of an algebra $A$ is a bounded distributive lattice ${\cal L}(A)$ whose prime spectrum of filters or ideals is homeomorphic to the prime spectrum of congruences of $A$, endowed with the Stone topologies. We have obtained a construction for the reticulation of any algebra $A$ from a semi-degenerate congruence-modular variety ${\cal C}$ in the case when the commutator of $A$, applied to compact congruences of $A$, produces compact congruences, in particular when ${\cal C}$ has principal commutators; furthermore, it turns out that weaker conditions than the fact that $A$ belongs to a congruence-modular variety are sufficient for $A$ to have a reticulation. This construction generalizes the reticulation of a commutative unitary ring, as well as that of a residuated lattice, which in turn generalizes the reticulation of a BL-algebra and that of an MV-algebra. The purpose of constructing the reticulation for the algebras from ${\cal C}$ is that of transferring algebraic and topological properties between the variety of bounded distributive lattices and ${\cal C}$, and a reticulation functor is particularily useful for this transfer. We have defined and studied a reticulation functor for our construction of the reticulation in this context of universal algebra.Comment: 29 page

Szubstrukturális logikák algebrai és bizonyításelméleti vizsgálata = Algebraic and Proof Theoretic Investigations of Substructural Logics

A kutatás fő eredményei: - Az ""Equality"" algebrák bevezetése (Studia Logica). - A ""strongly involutive uninorm"" algebrák bevezetése és osztályozása, valamint a vonatkozó logika komplexitásának vizsgálata (J Logic and Computation). - Az ""involutive FLe-monoid""-ok algebrai vizsgálata; kúp-reprezentáció és egyes véges láncok osztályozása (Archive for Mathematical Logic). - Az involutív uninormák egy osztályának osztályozása, az itt bevezetett ferde-szimmetrizáció segítségével (J Logic and Computation). - A forgatás konstrukció és az Ábel csoportok kapcsolatának vizsgálata (Fuzzy Sets and Systems). - A reziduált hálók geometriai jellegű vizsgálata (Annals of Pure and Applied Logic). Lektorálás alatt: az ""Elnyelő-folytonos, éles, szubreál láncon értelmezett FLe-algebrák osztályozása"" és a ""Pseudo Equality Algebras"" cikkek. | The scientific achievements of the project are the following: - The introducing of equality algebras (Studia Logica). - The introducing and classifying of strongly involutive uninorm algebras along with complexity issues of the related logic (J Logic and Computation). - Algebraic investigation of involutive FLe-monoids, in particular, conic representation and classification of certain finite chains (Archive for Mathematical Logic). - Structural description of a class of involutive uninorms via inrtoducing skew symmetrization (J Logic and Computation). - An investigation of the link between the rotation-construction and Abelian groups (Fuzzy Sets and Systems). - A geometric flavour study of residuated lattices (Annals of Pure and Applied Logic). - ""Classification of absorbent-continuous sharp FLe-algebras over subreal chains"" and Pseudo Equality Algebras"" (two articles under review

Transferring Davey`s Theorem on Annihilators in Bounded Distributive Lattices to Modular Congruence Lattices and Rings

Congruence lattices of semiprime algebras from semi--degenerate congruence--modular varieties fulfill the equivalences from B. A. Davey`s well--known characterization theorem for $m$--Stone bounded distributive lattices, moreover, changing the cardinalities in those equivalent conditions does not change their validity. I prove this by transferring Davey`s Theorem from bounded distributive lattices to such congruence lattices through a certain lattice morphism and using the fact that the codomain of that morphism is a frame. Furthermore, these equivalent conditions are preserved by finite direct products of such algebras, and similar equivalences are fulfilled by the elements of semiprime commutative unitary rings and, dualized, by the elements of complete residuated lattices.Comment: 18 page

Factor Varieties

The universal algebraic literature is rife with generalisations of discriminator varieties, whereby several investigators have tried to preserve in more general settings as much as possible of their structure theory. Here, we modify the definition of discriminator algebra by having the switching function project onto its third coordinate in case the ordered pair of its first two coordinates belongs to a designated relation (not necessarily the diagonal relation). We call these algebras factor algebras and the varieties they generate factor varieties. Among other things, we provide an equational description of these varieties and match equational conditions involving the factor term with properties of the associated factor relation. Factor varieties include, apart from discriminator varieties, several varieties of algebras from quantum and fuzzy logics