Reaping number and \(\pi\)-character of Boolean algebras. (English) Zbl 0766.06012

Summary: For every Boolean algebra \(B\) the minimal \(\pi\)-character of an ultrafilter on \(B\) is at most \(2^{r_ 2}\), where \(r_ 2\) is the reaping number of \(B\). An example of \(B\) is given for which \(r_ 2(B)<\min\{\pi\chi(U): U\in\text{Ult}(B)\}\).


06E15 Stone spaces (Boolean spaces) and related structures
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