Club and Stationary Sets in ω1, Probability Measures, and Ulam Matrices
نویسنده
چکیده
In this talk I will discuss some interesting subsets of ω1 – club-sets, Borel subsets, stationary and bi-stationary subsets of ω1 – and the theorem about them that has been most useful to me over the years, called Fodor’s Theorem. The question “How many types of stationary sets exist in ω1?” will be a recurring theme. (Spoiler alert: there are uncountably many really distinct stationary subsets of ω1.) In addition, I will mention some topological applications of stationary sets and Fodor’s Lemma that have interested me over the years.
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