On the implementation of set-valued non-Boolean functions.
On the injectivity of Boolean algebras
The functor taking global elements of Boolean algebras in the topos of sheaves on a complete Boolean algebra is shown to preserve and reflect injectivity as well as completeness. This is then used to derive a result of Bell on the Boolean Ultrafilter Theorem in -valued set theory and to prove that (i) the category of complete Boolean algebras and complete homomorphisms has no non-trivial injectives, and (ii) the category of frames has no absolute retracts.
On the lattice of subalgebras of a Boolean algebra
On the range of a Boolean transformation.
On The Range Of Boolean Transformation
On the reconstruction of Boolean algebras from their automorphism groups.
On the relationship between projective distributive lattices and Boolean algebras.
On the representation of orthocomplemented posets
On the structure of intuitionistic algebras with relational probabilities.
Trillas ([1]) has defined a relational probability on an intuitionistic algebra and has given its basic properties. The main results of this paper are two. The first one says that a relational probability on a intuitionistic algebra defines a congruence such that the quotient is a Boolean algebra. The second one shows that relational probabilities are, in most cases, extensions of conditional probabilities on Boolean algebras.
On the structure of numerical event spaces
The probability of the occurrence of an event pertaining to a physical system which is observed in different states determines a function from the set of states of the system to . The function is called a numerical event or multidimensional probability. When appropriately structured, sets of numerical events form so-called algebras of -probabilities. Their main feature is that they are orthomodular partially ordered sets of functions with an inherent full set of states. A classical...
On σ-complete prime ideals in Boolean algebras
One-way communication complexity of symmetric boolean functions
We study deterministic one-way communication complexity of functions with Hankel communication matrices. Some structural properties of such matrices are established and applied to the one-way two-party communication complexity of symmetric Boolean functions. It is shown that the number of required communication bits does not depend on the communication direction, provided that neither direction needs maximum complexity. Moreover, in order to obtain an optimal protocol, it is in any case sufficient...
One-way communication complexity of symmetric Boolean functions
We study deterministic one-way communication complexity of functions with Hankel communication matrices. Some structural properties of such matrices are established and applied to the one-way two-party communication complexity of symmetric Boolean functions. It is shown that the number of required communication bits does not depend on the communication direction, provided that neither direction needs maximum complexity. Moreover, in order to obtain an optimal protocol, it is in any case sufficient...
Openly generated Boolean algebras and the Fodor-type reflection principle
We prove that the Fodor-type Reflection Principle (FRP) is equivalent to the assertion that any Boolean algebra is openly generated if and only if it is ℵ₂-projective. Previously it was known that this characterization of openly generated Boolean algebras follows from Axiom R. Since FRP is preserved by c.c.c. generic extension, we conclude in particular that this characterization is consistent with any set-theoretic assertion forcable by a c.c.c. poset starting from a model of FRP. A crucial step...
Opérations dérivées des treillis orthomodulaires (Part 3)
Orthogonal and prereflective subcategories
Orthomodular lattices that are horizontal sums of Boolean algebras
The paper deals with orthomodular lattices which are so-called horizontal sums of Boolean algebras. It is elementary that every such orthomodular lattice is simple and its blocks are just these Boolean algebras. Hence, the commutativity relation plays a key role and enables us to classify these orthomodular lattices. Moreover, this relation is closely related to the binary commutator which is a term function. Using the class of horizontal sums of Boolean algebras, we establish an identity which...
Outer measure on boolean algebras
Partially additive states on orthomodular posets
We fix a Boolean subalgebra B of an orthomodular poset P and study the mappings s:P → [0,1] which respect the ordering and the orthocomplementation in P and which are additive on B. We call such functions B-states on P. We first show that every P possesses "enough" two-valued B-states. This improves the main result in [13], where B is the centre of P. Moreover, it allows us to construct a closure-space representation of orthomodular lattices. We do this in the third section. This result may also...
Partitions of -branching trees and the reaping number of Boolean algebras
The reaping number of a Boolean algebra is defined as the minimum size of a subset such that for each -partition of unity, some member of meets less than elements of . We show that for each , as conjectured by Dow, Steprāns and Watson. The proof relies on a partition theorem for finite trees; namely that every -branching tree whose maximal nodes are coloured with colours contains an -branching subtree using at most colours if and only if .