In the category of archimedean lattice-ordered groups with strong unit, the Yosida representation provides an insightful description of coproducts and the condition that an object be hyperarchimedean. These are combined to yield a criterion that a coproduct be hyperarchimedean and this is applied, viz.: ${G \coprod G}$ is hyperarchimedean if and only if G is Specker (here meaning an ?-group of real-valued step functions). ${G \coprod H}$ is hyperarchimedean for every hyperarchimedean H if and only if G is Specker and rational-valued. If {G i } I is a collection of Specker groups, then ${\coprod_ I G_i}$ is Specker, thus hyperarchimedean. If ${\coprod_I H_i}$ is hyperarchimedean, then the non-Specker H i number at most ${\mathfrak{c}}$ and satisfy a condition of rational-linear independence of values.
中欧数学杂志（ CEJM ）的是，出版研究成果在各领域的数学国际期刊。旨在成为中欧和东欧的高质量研究的主要来源，该杂志提供了一个自然的家当前研究的一个显著的身体，并作为思想一个有用的论坛上在数学的所有分支未来的研究。覆盖CEJM包括： - 代数 - 复分析 - 微分方程 - 离散数学 - 功能分析 - 几何与拓扑 - 数理逻辑与基础 - 数论 - 数值分析与优化 - 概率统计 - 实时分析。 |
