The Midwest Computability Seminar is a joint venture between the University of Chicago, the University of Notre Dame, and the University of Wisconsin-Madison. It meets once or twice per semester at the University of Chicago, and is attended by faculty and students from these universities and others in the area. The seminar started in the fall of 2008.

DATE: Tuesday, May 2nd, 2023

PLACE: Ryerson Hall 352 (the Barn), The University of Chicago.

1100 East 58th Street, Chicago, IL 60637.

REMOTE ATTENDANCE: https://notredame.zoom.us/j/99754332165?pwd=RytjK1RFZU5KWnZxZ3VFK0g4YTMyQT09

Meeting ID: 997 5433 2165

Passcode: midwest

Speakers:

- Peter Gerdes - Indiana University, Bloomington

- Joel David Hamkins - University of Notre Dame

- Matthew Harrison-Trainor - University of Michigan

- 12:00 - 1:00 The Barn will be available for a brown bag
lunch
- 1:00 - 1:50 Peter Gerdes

- 2:00 - 2:30 Coffee Break
- 2:30 - 3:20 Joel Hamkins

- 3:30 - 4:00 Coffee Break

- 4:00 - 4:50 Matthew Harrison-Trainor

- 5:30 Dinner at Nella, 1125 E. 55th St.

Title: A non-trivial 3-REA set not computing a 3-generic

Abstract: It's well known that every non-computable r.e. set computes a 1-generic. In this talk I review this result, discuss the generalization to 2-REA sets and, if time permits, discuss a new result that there is a 3-REA set not computable from 0'' that doesn't compute a weak 3-generic.

Title: Set-theoretic forcing as a computational process

Abstract: I shall explore several senses in which set-theoretic forcing can be seen as a computational process on the models of set theory. Given an oracle for the atomic or elementary diagram of a model (

Title: True stages and descriptive set theory

Abstract: I will explain how true stage constructions from computability theory can be used to prove strong change-of-topology results in descriptive set theory. A classical tool of descriptive set theory is to take a countable collection of Borel sets (often the sets of a particular lightface Borel complexity) and change the topology to make them open. Using the true stage machinery, we can create a tree (analagous to the trees of finite sequences for the usual topologies on Baire space and Cantor space) such that the closed sets of the new topology correspond to the sets of paths through a subtree. I will explain how this is done together with some applications. This is joint work with Adam Day, Noam Greenberg, and Dan Turetsky.

- Sept 23rd 2008 Antonio Montalbán - Logan Axon - Joe Miller
- Nov 11th 2008 Chris Conidis - Keng Meng (Selwyn) Ng - Peter Gerdes
- Feb 3rd 2009 David Diamondstone - Bart Kastermans - Richard A. Shore
- April 21st 2009 Dan Turetsky - Julia Knight - Ted Slaman
- Sept 29th 2009 Carl Jockusch - Rachel Epstein - Rebecca Weber
- Jan 26th 2010 Sara Quinn - John Wallbaum - Steffen Lempp - Reed Solomon
- May 11th 2010 Adam Day - Liang Yu - Rod Downey - Boris Zilber
- Sept 28th 2010 Maurice Chiodo - Peter Gerdes - Damir Dzhafarov - Andy Lewis
- Feb 15th 2011 Uri Andrews - Paola D'Aquino - David Diamondstone - Christopher Porter - Rebecca Steiner
- Nov 1st 2011 Mingzhong Cai - Chris Conidis - Stephen Flood - Jeff Hirst - Asher Kach
- Nov 15th 2012 Achilles Beros - Rod Downey - Jesse Johnson - Sam Sanders - Steven VanDendriessche - Matthew Wright
- April 2nd 2013 Howard Becker - Denis Hirschfeldt - Paul Schupp
- October 1st 2013 Peter Cholak - Mushfeq Khan - Victor Ocasio-González - Jonathan Stephenson
- April 29th, 2014 Rod Downey - Noam Greenberg - Gregory Igusa - Alexander Melnikov - Kyle Riggs
- September 30th, 2014 Eric Astor - Quinn Culver - Jack Lutz - Timothy McNicholl
- February 17th, 2015 Carl Jockusch - Julia Knight - Steffen Lempp
- January 28th, 2016 Reese Johnston - Rutger Kuyper - Mariya Soskova - Mars Yamaleev
- October 22nd and 23rd, 2016 Special Meeting in Honor of Carl Jockusch's 75th Birthday
- March 16th, 2017 Greg Igusa - Jack Lutz - Sasha Melnikov - Reed Solomon
- October 24th, 2017 Noah Schweber - Don Stull - Dan Turetsky - Rose Weisshaar
- April 17th, 2018 Peter Cholak - Meng-Che "Turbo" Ho - Ethan McCarthy - Joe Miller
- October 9th, 2018 Uri Andrews - Timothy McNicholl - Alexandra Soskova
- April 18th, 2019 Wesley Calvert - Russell Miller - Steffen Lempp
- February 11th, 2020 Rachael Alvir - Tejas Bhojraj - Jun Le Goh - Neil Lutz
- August - December, 2020 Nine Online Talks
- February - May, 2021 Seven Online Talks
- September - December, 2021 Ten Online Talks
- January - April, 2022 Six Online Talks
- November 1st, 2022 Luca San Mauro - Donald Stull - Manlio Valenti

If you haven't been receiving the announcements and would like to be included in the list, send an email to drh@math.uchicago.edu.