The amalgamation property of varieties determined by primitive lattices
We set up axioms characterizing logical connective implication in a logic derived by an ortholattice. It is a natural generalization of an orthoimplication algebra given by J. C. Abbott for a logic derived by an orthomodular lattice.
If is a commutative ring with identity and is defined by letting mean or , then is a partially ordered ring. Necessary and sufficient conditions on are given for to be a lattice, and conditions are given for it to be modular or distributive. The results are applied to the rings of integers mod for . In particular, if is reduced, then is a lattice iff is a weak Baer ring, and is a distributive lattice iff is a Boolean ring, , , or a four element field.
In this work we show that the Bruhat rank of a symmetric (0,1)-matrix of order n with a staircase pattern, total support, and containing In, is at most 2. Several other related questions are also discussed. Some illustrative examples are presented.
We define “the category of compactifications”, which is denoted CM, and consider its family of coreflections, denoted corCM. We show that corCM is a complete lattice with bottom the identity and top an interpretation of the Čech–Stone . A corCM implies the assignment to each locally compact, noncompact a compactification minimum for membership in the “object-range” of . We describe the minimum proper compactifications of locally compact, noncompact spaces, show that these generate the atoms...