Series: Penn State Logic Seminar

Date: Tuesday, September 21, 2004

Time: 2:30 - 3:45 PM

Place: 307 Boucke Building

Speaker: John Clemens, Penn State, Mathematics

Title: The Wadge Degrees, part 1

  Given two subsets A and B of the Baire space (or the Cantor space),
  we say that A is Wadge reducible to B if A is a continuous preimage
  of B.  The equivalence classes under this ordering are called Wadge
  degrees.  The structure of the Wadge degrees has a rich theory which
  can be analyzed using infinite games, and under determinacy
  assumptions about these games the structure is completely
  determined.  I will give an overview of this area and prove some of
  the main properties.