AROUND cofin

作者：Roslanowski Andrzej^*; Shelah Saharon

来源：Colloquium Mathematicum, 2014, 134(2): 211-225.

DOI：10.4064/cm134-2-5

• cardinal invariants
• Borel ideals
• cofin
• forcing

We show the consistency of "there is a nice sigma-ideal I on the reals with add(I) = N-1 which cannot be represented as the union of a strictly increasing sequence of length omega(1) of sigma-subideals". This answers [Borodulin-Nadzieja and Glab, Math. Logic Quart. 57 (2011), 582-590, Problem 6.2(ii)].

• 出版日期2014
• 单位rutgers