Series: Penn State Logic Seminar Date: Tuesday, September 13, 2005 Time: 2:30 - 3:45 PM Place: 106 McAllister Building Speaker: Stephen G. Simpson, Penn State, Mathematics Title: The Reverse Mathematics of Ramsey's Theorem, part 3 Abstract: We use Mathias forcing to prove the following lemma. Let C_i, i = 0, 1, 2, ... be a sequence of non-recursive subsets of omega. Let U be an arbitrary subset of omega. Then there exists a subset of omega, A, which is either included in or disjoint from U, and such that for all i, C_i is not recursive relative to A. From this lemma, Seetapun's Theorem will follow easily.
Mathematical Logic at Penn State
Department of Mathematics