超滤子可除性的综述
A survey on divisibility of ultrafilters
AI总结:
本文综述了自然数可除性关系向超滤子集合扩展的研究,总结了分区、碎片化及同余扩展等核心成果。
摘要:
在过去十年中,若干论文定义并研究了 $\mathbb{N}$ 上的可除性关系向 $\mathbb{N}$ 上的超滤子集合 $β\mathbb{N}$ 的扩展。本文对迄今取得的成果进行了综述,并补充了若干将不同研究阶段的主题联系起来的结果。亮点包括:将 $β\mathbb{N}$ 划分为下部 $L$(及其按层级的划分)和上部;识别基本要素(素数的幂)以及每个超滤子向这些要素的碎片化;寻找具有给定基本要素的超滤子所对应的向上封闭集;给定可除性类的后继与前驱的存在性及数量;扩展同余关系(以两种方式)并检验所得关系的性质。
英文摘要:
An extension of the divisibility relation on $\mathbb{N}$ to the set $β\mathbb{N}$ of ultrafilters on $\mathbb{N}$ was defined and investigated in several papers during the last ten years. Here we make a survey of results obtained so far, adding several results connecting the themes of different stages of the research. The highlights include: separation of $β\mathbb{N}$ into the lower part $L$ (with its division into levels) and the upper part; identifying basic ingredients (powers of primes) and fragmentation of each ultrafilter into them; finding the corresponding upward closed sets belonging to an ultrafilter with given basic ingredients; existence and number of successors and predecessors of a given divisibility class; extending the congruence relation (in two ways) and checking properties of the obtained relations.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。