Page 1 Next

Displaying 1 – 20 of 82

Showing per page

A note on Möbius inversion over power set lattices

Klaus Dohmen (1997)

Commentationes Mathematicae Universitatis Carolinae

In this paper, we establish a theorem on Möbius inversion over power set lattices which strongly generalizes an early result of Whitney on graph colouring.

A representation theorem for certain Boolean lattices.

José Ríos Montes (1988)

Publicacions Matemàtiques

Let R be an associative ring with 1 and R-tors the somplete Brouwerian lattice of all hereditary torsion theories on the category of left R-modules. A well known result asserts that R is a left semiartinian ring iff R-tors is a complete atomic Boolean lattice. In this note we prove that if L is a complete atomic Boolean lattice then there exists a left semiartinian ring R such that L is lattice-isomorphic to R-tors.

Cellularity of free products of Boolean algebras (or topologies)

Saharon Shelah (2000)

Fundamenta Mathematicae

The aim this paper is to present an answer to Problem 1 of Monk [10], [11]. We do this by proving in particular that if μ is a strong limit singular cardinal, θ = ( 2 c f ( μ ) ) + and 2 μ = μ + then there are Boolean algebras 𝔹 1 , 𝔹 2 such that c ( 𝔹 1 ) = μ , c ( 𝔹 2 ) < θ b u t c ( 𝔹 1 * 𝔹 2 ) = μ + . Further we improve this result, deal with the method and the necessity of the assumptions. In particular we prove that if 𝔹 is a ccc Boolean algebra and μ ω λ = c f ( λ ) 2 μ then 𝔹 satisfies the λ-Knaster condition (using the “revised GCH theorem”).

Choice principles in Węglorz’ models

N. Brunner, Paul Howard, Jean Rubin (1997)

Fundamenta Mathematicae

Węglorz' models are models for set theory without the axiom of choice. Each one is determined by an atomic Boolean algebra. Here the algebraic properties of the Boolean algebra are compared to the set theoretic properties of the model.

Disjoint sequences in Boolean algebras

Ján Jakubík (1998)

Mathematica Bohemica

We deal with the system Conv B of all sequential convergences on a Boolean algebra B . We prove that if α is a sequential convergence on B which is generated by a set of disjoint sequences and if β is any element of Conv B , then the join α β exists in the partially ordered set Conv B . Further we show that each interval of Conv B is a Brouwerian lattice.

Currently displaying 1 – 20 of 82

Page 1 Next