论文标题
关于$δ$ - 施加紧凑型红衣主教的注释
A note on $δ$-strongly compact cardinals
论文作者
论文摘要
在本文中，我们研究了$δ$ stronglongly紧凑型红衣主教的更多特征和应用。我们表明，对于红衣主教$κ$，以下等同：（1）$κ$是$Δ$ - stronglongly compact，（2）对于每一个常规$λ\geκ$，$Δ$Δ$ - complete Ultrafter超过$λ$，并且（3）每个产品$δ$ -Lindelefeluf $ $ $ $ - 我们还证明，在Cohen强迫扩展中，至少$ω_1$ - 紧凑型红衣主教是两个次数紧密的空间的紧密度上的精确上限。
In this paper we investigate more characterizations and applications of $δ$-strongly compact cardinals. We show that, for a cardinal $κ$ the following are equivalent: (1) $κ$ is $δ$-strongly compact, (2) For every regular $λ\ge κ$ there is a $δ$-complete uniform ultrafilter over $λ$, and (3) Every product space of $δ$-Lindelöf spaces is $κ$-Lindelöf. We also prove that in the Cohen forcing extension, the least $ω_1$-strongly compact cardinal is a precise upper bound on the tightness of the products of two countably tight spaces.
