We define type A, type B, type C as well as C∗-semi-finite C∗-algebras. It is shown that a von Neumann algebra is a type A, type B, type C or C∗-semi-finite C∗-algebra if and only if it is, respectively, a type I, type II, type III or semi-finite von Neumann algebra. Moreover, any type I C∗-algebra is of type A (actually, type A coincides with the discreteness as defined by Peligrad and Zsidó),...

In this paper, we prove various results concerning DGA-algebras in the context of the Homological Perturbation Theory. We distinguish two class of contractions for algebras: full algebra contractions and semi-full algebra contractions. A full algebra contraction is, in particular , a semi-full algebra contraction. Taking a full algebra contraction and an \algebra perturbation" as data of the Ba...

Simulations and bisimulations between two fuzzy automata over a complete residuated lattice were defined by Ćirić et al. (2012) [7], [8] as relations the sets of states automata. However, they act crisp relationship In particular, if there exists (forward) bisimulation automata, then languages recognized them are crisply equal. Approximate simulations introduced Stanimirović (2022) [36] aim at ...

In this paper, we show that there exist (continuum many) varieties of bi-Heyting algebras are not generated by their complete members. It follows extensions the Heyting–Brouwer logic [Formula: see text] topologically incomplete. This result provides further insight into long-standing open problem Kuznetsov yielding a negative solution reformulation from to text].

An effect in quantum mechanics on a Hilbert space H is an operator A in H such that 0 ≤ A ≤ I , and two effects, A and B, are added to get A⊕ B iff 0 ≤ A⊕ B ≤ I, where A⊕ B is the operator addition. We wish to specialize this concept to the effects that arise naturally in the formalism of quantum mechanics on phase space (Schroeck, 1996). From this, we will have an immediate generalization to H...

The techniques of natural duality theory are applied to certain finitely generated varieties of Heyting algebras to obtain optimal dualities for these varieties, and thereby to address algebraic questions about them. In particular, a complete characterisation is given of the endodualisable finite subdirectly irreducible Heyting algebras. The procedures involved rely heavily on Priestley duality...

A subresiduated lattice is a pair (A, D), where bounded distributive lattice, D sublattice of and for every $$a,b\in A$$ there $$c\in D$$ such that all $$d\in , $$d\wedge a\le b$$ if only $$d\le c$$ . This c denoted by $$a\rightarrow can be regarded as an algebra $$\left$$ type (2, 2, 0, 0) $$D=\{a\in A\mid 1\rightarrow a=a\}$$ The class lattices variety ...