Graduate Logic Seminar: Difference between revisions

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Sign up for the graduate logic seminar mailing list:  join-grad-logic-sem@lists.wisc.edu
Sign up for the graduate logic seminar mailing list:  join-grad-logic-sem@lists.wisc.edu


== Fall 2021 tentative schedule ==
== Spring 2022 ==


To see what's happening in the Logic qual preparation sessions click [[Logic Qual Prep|here]].
The graduate logic seminar this semester will be run as MATH 975. Please enroll if you wish to participate.


=== September 14 - organizational meeting ===
We plan to cover the first 9 parts of [https://blog.nus.edu.sg/matwong/teach/modelarith/ Tin Lok Wong's notes], as well as a few other relevant topics which are not covered in the notes:
* Properness of the induction/bounding hierarchy (chapter 10 of Models of Peano Arithmetic by Kaye is a good source)
* Tennenbaum's theorem (this is a quick consequence of the main theorem of part 4, so it should be combined with part 4 or part 5)
* Other facts found in chapter 1 of [http://homepages.math.uic.edu/~marker/marker-thesis.pdf David Marker's thesis].


We met to discuss the schedule.
=== January 25 - organizational meeting ===


=== September 28 - Ouyang Xiating ===
We will meet to assign speakers to dates.


Title: First-order logic, database and consistent query answering
=== February 1 - Steffen Lempp ===


Abstract: Databases are a crucial component of many (if not all) modern
I will give an overview of the topics we will cover:  
applications. In reality, the data stored are often dirty and contain
duplicated/missing entries, and it is a natural practice to clean the data
first before executing the query. However, the same query might return
different answers on different cleaned versions of the dataset. It is then
helpful to compute the consistent answers: the query answers that will always
be returned, regardless of how the dirty data is cleaned. In this talk, we
first introduce the connection between first-order logic and query languages
on databases, and then discuss the problem of Consistent Query Answering
(CQA): How to compute consistent answers on dirty data? Finally, we show
when the CQA problem can be solved using first-order logic for path queries.


=== October 12 - Karthik Ravishankar ===
1. the base theory PA^- and the induction and bounding axioms for Sigma_n-formulas, and how they relate to each other,


Title: Notions of randomness for subsets of the Natural Numbers
2. the equivalence of Sigma_n-induction with a version of Sigma_n-separation (proved by H. Friedman),


Abstract: There are a number of notions of randomness of sets of natural numbers. These notions have been defined based on what a 'random object' should behave like such as being 'incompressible' or being 'hard to predict' etc. There is often a interplay between computability and randomness aspects of subsets of natural numbers. In this talk we motivate and present a few different notions of randomness and compare their relative strength.
3. the Grzegorczyk hierarchy of fast-growing functions,


=== October 26 - no seminar ===
4. end extensions and cofinal extensions,


=== November 9 - Antonio Nákid Cordero ===
5. recursive saturation and resplendency,


Title: Martin's Conjecture: On the uniqueness of the Turing jump
6. standard systems and coded types,


Abstract: The partial order of the Turing degrees is well-known to be extremely complicated. However, all the Turing degrees that appear "naturally" in mathematics turn out to be well-ordered. In the '70s, Martin made a sharp conjecture explaining this phenomenon, the prime suspect: the Turing jump. This talk will explore the precise statement of Martin's conjecture and the interesting mathematics that surround it.
7. the McDowell-Specker Theorem that every model of PA has a proper elementary end extension, and


=== November 23 - Antonio Nákid Cordero? ===
8. Gaifman's theorem that every model of PA has a minimal elementary end extension.


=== December 7 - John Spoerl ===
I will sketch the basic definitions and state the main theorems, in a form that one can appreciate without too much
background.


== Previous Years ==
== Previous Years ==


The schedule of talks from past semesters can be found [[Graduate Logic Seminar, previous semesters|here]].
The schedule of talks from past semesters can be found [[Graduate Logic Seminar, previous semesters|here]].

Revision as of 21:28, 18 January 2022

The Graduate Logic Seminar is an informal space where graduate students and professors present topics related to logic which are not necessarily original or completed work. This is a space focused principally on practicing presentation skills or learning materials that are not usually presented in a class.

  • When: Tuesdays 4-5 PM
  • Where: Van Vleck 901
  • Organizers: Jun Le Goh

The talk schedule is arranged at the beginning of each semester. If you would like to participate, please contact one of the organizers.

Sign up for the graduate logic seminar mailing list: join-grad-logic-sem@lists.wisc.edu

Spring 2022

The graduate logic seminar this semester will be run as MATH 975. Please enroll if you wish to participate.

We plan to cover the first 9 parts of Tin Lok Wong's notes, as well as a few other relevant topics which are not covered in the notes:

  • Properness of the induction/bounding hierarchy (chapter 10 of Models of Peano Arithmetic by Kaye is a good source)
  • Tennenbaum's theorem (this is a quick consequence of the main theorem of part 4, so it should be combined with part 4 or part 5)
  • Other facts found in chapter 1 of David Marker's thesis.

January 25 - organizational meeting

We will meet to assign speakers to dates.

February 1 - Steffen Lempp

I will give an overview of the topics we will cover:

1. the base theory PA^- and the induction and bounding axioms for Sigma_n-formulas, and how they relate to each other,

2. the equivalence of Sigma_n-induction with a version of Sigma_n-separation (proved by H. Friedman),

3. the Grzegorczyk hierarchy of fast-growing functions,

4. end extensions and cofinal extensions,

5. recursive saturation and resplendency,

6. standard systems and coded types,

7. the McDowell-Specker Theorem that every model of PA has a proper elementary end extension, and

8. Gaifman's theorem that every model of PA has a minimal elementary end extension.

I will sketch the basic definitions and state the main theorems, in a form that one can appreciate without too much background.

Previous Years

The schedule of talks from past semesters can be found here.