Boolean Algebras with Finite Families of Computable Automorphisms

We prove that each computable Boolean algebra has a computable presentation in which for every computable family of automorphisms the set of atoms moved by at least one of its members is finite. This implies that each computable atomic Boolean algebra has a computable presentation in which its every computable family of automorphisms is finite. The priority argument is not used in the proof.     

Hyperarithmetical Boolean Algebras with a Distinguished Ideal

We prove a general theorem that allows us to pass from a hyperarithmetical Boolean algebra with a distinguished ideal to some computable Boolean algebra connected with the former by natural algebraic operations. Some examples are given.     

IMTL代数上的素布尔滤子格

本文研究IMTL代数M上的索布尔滤子的运算性质。令FB（M）为膨上全体素布尔滤子集，FB（M）=FB（M）∪{φ}，通过在集合FB（M）引进格并、交运算和逆序对合对应，证明了FB（M）构成一个拟布黎代数。进一步在FB（M）可定义一个伴随对，证明FB（M）也构成一个剩余格。     

Computable Homogeneous Boolean Algebras and a Metatheorem

We consider computable homogeneous Boolean algebras. Previously, countable homogeneous Boolean algebras have been described up to isomorphism and a simple criterion has been found for the existence of a strongly constructive (decidable) isomorphic copy for such. We propose a natural criterion for the existence of a constructive (computable) isomorphic copy. For this, a new hierarchy of -computable functions and sets is introduced, which is more delicate than Feiner's. Also, a metatheorem is proved connecting computable Boolean algebras and their hyperarithmetical quotient algebras.     

Partition Complete Boolean Algebras and Almost Compact Cardinals

For an infinite cardinal K a stronger version of K-distributivity for Boolean algebras, called k-partition completeness, is defined and investigated (e. g. every K-Suslin algebra is a K-partition complete Boolean algebra). It is shown that every k-partition complete Boolean algebra is K-weakly representable, and for strongly inaccessible K these concepts coincide. For regular K ≥ u, it is proved that an atomless K-partition complete Boolean algebra is an updirected union of basic K-tree algebras. Using K-partition completeness, the concept of γ-almost compactness is introduced for γ ≥ K. For strongly inaccessible K we show that K is K-almost compact iff K is weakly compact, and if K is 2^K-almost compact, then K is measurable. Further K is strongly compact iff it is γ-almost compact for all γ ≥ K.     

Computable Families of Superatomic Boolean Algebras

We describe the families of superatomic Boolean algebras which have a computable numbering. We define the notion of majorizability and establish a criterion that is formulated only on using algorithmic terms and majorizability. We give some examples showing that the condition of majorizability is essential. We also prove some criterion for the existence of a computable numbering for a family of -atomic algebras ( is a computable ordinal).     

Degree Spectra of Relations on Boolean Algebras

We show that every computable relation on a computable Boolean algebra is either definable by a quantifier-free formula with constants from (in which case it is obviously intrinsically computable) or has infinite degree spectrum.     

Sequential Convergences on Boolean Algebras Defined by Systems of Maximal Filters

We study sequential convergences defined on a Boolean algebra by systems of maximal filters. We describe the order properties of the system of all such convergences. We introduce the category of 2-generated convergence Boolean algebras and generalize the construction of Novak sequential envelope to such algebras.     

Boolean Algebras and Distributive Lattices Treated Constructively

Some aspects of the theory of Boolean algebras and distributive lattices–in particular, the Stone Representation Theorems and the properties of filters and ideals–are analyzed in a constructive setting.     

Rudin‐Keisler Posets of Complete Boolean Algebras

The Rudin‐Keisler ordering of ultrafilters is extended to complete Boolean algebras and characterised in terms of elementary embeddings of Boolean ultrapowers. The result is applied to show that the Rudin‐Keisler poset of some atomless complete Boolean algebras is nontrivial.     

Boole代数上的度量结构及其在命题逻辑中的应用

设B是一个Boole代数, Ω是从B到Boole代数{0,1}的全体同态之集,μ是Ω上的概率测度.本文基于μ在B中引入了元素的尺寸概念以及元素对之间的相似度概念,并由此在B上建立了度量结构.作为应用,本文改进了新近提出的命题逻辑中的近似推理理论.     

Some Boolean Algebras with Finitely Many Distinguished Ideals I

We consider the theory Th_prin of Boolean algebras with a principal ideal, the theory Th_max of Boolean algebras with a maximal ideal, the theory Th_ac of atomic Boolean algebras with an ideal where the supremum of the ideal exists, and the theory Th_sa of atomless Boolean algebras with an ideal where the supremum of the ideal exists. First, we find elementary invariants for Th_prin and Th_sa. If T is a theory in a first order language and α is a linear order with least element, then we let Sentalg(T) be the Lindenbaum-Tarski algebra with respect to T, and we let intalg(α) be the interval algebra of α. Using rank diagrams, we show that Sentalg(Th_prin) ? intalg(ω⁴), Sentalg(Th_max) ? intalg(ω³) ? Sentalg(Th_ac), and Sentalg(Th_sa) ? intalg(ω² + ω²). For Th_max and Th_ac we use Ershov's elementary invariants of these theories. We also show that the algebra of formulas of the theory Tx of Boolean algebras with finitely many ideals is atomic.     

A Note on Boolean Algebras with Few Partitions Modulo some Filter

We show that for every uncountable regular κ and every κ-complete Boolean algebra B of density ≤ κ there is a filter F ? B such that the number of partitions of length < modulo κF is ≤2^<κ. We apply this to Boolean algebras of the form P(X)/I, where I is a κ-complete κ-dense ideal on X. Mathematics Subject Classification: 06E05, 03C20.     

On the Absolute Continuity of Gaussian Measures on Locally Compact Groups

This note discusses the topological necessary and sufficient conditions for a locally compact connected group to admit a Gaussian measure that is absolutely continuous with respect to Haar measure.     

Weakly o‐Minimal Expansions of Boolean Algebras

We propose a definition of weak o‐minimality for structures expanding a Boolean algebra. We study this notion, in particular we show that there exist weakly o‐minimal non o‐minimal examples in this setting.     

Locally M-Pseudoconvex Topologies on Locally A-Pseudoconvex Algebras

Let (A, T) be a locally A-pseudoconvex algebra over or . We define a new topology m(T) on A which is the weakest among all m-pseudoconvex topologies on A stronger than T. We describe a family of non-homogeneous seminorms on A which defines the topology m(T).     

Boolean products of R0‐algebras

In this paper, the (weak) Boolean representation of R₀‐algebras are investigated. In particular, we show that directly indecomposable R₀‐algebras are equivalent to local R₀‐algebras and any nontrivial R₀‐algebra is representable as a weak Boolean product of local R₀‐algebras (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

布尔代数的直觉T-S模糊子代数及理想

在布尔代数中引入了的直觉T-S模糊子代数和直觉T-S模糊理想的概念,给出了布尔代数的直觉T-S模糊子代数的两个等价定义,进一步讨论了它们的性质.证明了布尔代数的两个直觉T-S模糊子代数(理想)的模交与直积也是直觉T-S模糊子代数(理想).     

原子Boolean格代数的导子

设L是Banach空间X上的原子Boolean子空间格,δ是algL的任一导子,则存在X中的一个稠定线性算子T,使得δ（A）＝AT—TA（A∈algL）在T的定义域D（T）上成立．另外,如果L还是一个有限格,并且对L的任一原子L,L＋L＇闭,则δ是连续的和内的．