arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1704.00511math.LO
收藏

可测基数和良好的$Σ_1(κ)$ -优序

Measurable cardinals and good $Σ_1(κ)$-wellorderings

Philipp Lücke, Philipp Schlicht

摘要:

研究了大基数的存在性对无限基数的幂集$κ$的wellordering存在性的影响,其中wellordering的所有初始段的集合可由带参数$κ$的$Σ_1$ -公式定义.一个简短的论点表明,存在一个可测基数$δ$意味着这样的wellorderings不存在于$δ$ -不可达的基数的共尾性不等于$δ$和他们的继任者。与此相反,我们的主要结果表明,这些wellordering存在于所有其他的不可数基数在最小模型含有一个可测基数。此外,我们还证明了可测性是在不可数基数上干扰这种wellorderings存在的最小的大基数性质,并将上述结果推广到包含两个可测基数的极小模型。

英文摘要:

We study the influence of the existence of large cardinals on the existence of wellorderings of power sets of infinite cardinals $κ$ with the property that the collection of all initial segments of the wellordering is definable by a $Σ_1$-formula with parameter $κ$. A short argument shows that the existence of a measurable cardinal $δ$ implies that such wellorderings do not exist at $δ$-inaccessible cardinals of cofinality not equal to $δ$ and their successors. In contrast, our main result shows that these wellorderings exist at all other uncountable cardinals in the minimal model containing a measurable cardinal. In addition, we show that measurability is the smallest large cardinal property that interferes with the existence of such wellorderings at uncountable cardinals and we generalize the above result to the minimal model containing two measurable cardinals.

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。

↑