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TZID:America/Chicago
BEGIN:DAYLIGHT
DTSTART:20260308T030000
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DTSTART:20261101T010000
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BEGIN:VEVENT
DTSTAMP;TZID=America/Chicago:20260904T170916
UID:224982@calendar.wisc.edu
DTSTART;TZID=America/Chicago:20260908T160000
DTEND;TZID=America/Chicago:20260908T170000
DESCRIPTION:Steffen Lempp (UW) - The theory of the Ziegler degrees. Abstrac
 t - The Ziegler degrees were introduced to characterize definability in gr
 oup theory. In joitn work with Jacobsen-Grocott and I. Scott\, I had shown
  that the first order-theory of the Ziegler degrees (as a partial order) i
 s undecidable. In joint work with Downey and I. Scott\, we have now improv
 ed this result\, showing that the theory of the Ziegler degrees is bi-inte
 rpretable with true second-order arithmetic.\n\nURL: https://web.math.wisc
 .edu/logic/seminar.html
LOCATION:901 Van Vleck Hall
SUMMARY:Logic Seminar
URL;VALUE=URI:https://web.math.wisc.edu/logic/seminar.html
END:VEVENT
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