Difference between revisions of "Graduate Logic Seminar"

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(Tuesday, November 24 - Tonicha Crook (Swansea University) from 9:00AM-10:00AM)
 
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The Graduate Logic Seminar is an informal space where graduate student and professors present topics related to logic which are not necessarly 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.
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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:''' Mondays 4p-5p
+
* '''When:''' Mondays 4p-5p (unless stated otherwise)
* '''Where:''' Van Vleck B223.
+
* '''Where:''' on line (ask for code).
* '''Organizers:''' [https://www.math.wisc.edu/~omer/ Omer Mermelstein]
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* '''Organizers:''' [https://www.math.wisc.edu/~jgoh/ 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.
 
The talk schedule is arranged at the beginning of each semester. If you would like to participate, please contact one of the organizers.
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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
  
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== Fall 2020 - Tentative schedule ==
  
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=== September 14 - Josiah Jacobsen-Grocott ===
  
== Fall 2019 - Tentative schedule ==
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Title: Degrees of points in topological spaces
  
=== September 5 - Organizational meeting ===
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Abstract: An overview of some results from Takayuki Kihara, Keng Meng Ng, and Arno Pauly in their paper Enumeration Degrees and Non-Metrizable Topology. We will look at a range of topological spaces and the corresponding classes in the enumeration degrees as well as ways in which we can distinguish the type of classes using the separation axioms.
  
=== September 9 - No seminar ===
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=== September 28 - James Hanson ===
  
=== September 16 - Daniel Belin ===
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Title: The Semilattice of Definable Sets in Continuous Logic
Title: Lattice Embeddings of the m-Degrees and Second Order Arithmetic
 
  
Abstract: Lachlan, in a result later refined and clarified by Odifreddi, proved in 1970 that initial segments of the m-degrees can be embedded as an upper semilattice formed as the limit of finite distributive lattices. This allows us to show that the many-one degrees codes satisfiability in second-order arithmetic, due to a later result of Nerode and Shore. We will take a journey through Lachlan's rather complicated construction which sheds a great deal of light on the order-theoretic properties of many-one reducibility.
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Abstract: After an analysis-free exposition of definable sets in continuous logic, we will present a fun, illustrated proof that any finite bounded lattice can be the poset of definable subsets of $S_1(T)$ for a continuous theory $T$.
  
=== September 23 - Daniel Belin ===
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=== October 5 - Tejas Bhojraj from 3:30PM-4:00PM ===
  
Title: Lattice Embeddings of the m-Degrees and Second Order Arithmetic - Continued
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Title: A Levin-Schnorr type result for Weak Solovay random states.
  
=== September 30 - Josiah Jacobsen-Grocott ===
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Abstract: We look at the initial-segment complexity of Weak Solovay quantum random states using MK, a prefix-free version of quantum Kolmogorov complexity. The statement of our result is similar to the Levin-Schnorr theorem in classical algorithmic randomness.
  
Title: Scott Rank of Computable Models
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=== November 9 - Karthik Ravishankar ===
  
Abstract: Infinatary logic extends the notions of first order logic by allowing infinite formulas. Scott's Isomorphism Theorem states that any countable structure can be characterized up to isomorphism by a single countable sentence. Closely related to the complexity of this sentence is what is known as the Scott Rank of the structure. In this talk we restrict our attention to computable models and look at an upper bound on the Scott Rank of such structures.
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Title: Elementary submodels in infinite combinatorics
  
=== October 7 - Josiah Jacobsen-Grocott ===
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Abstract: The usage of elementary submodels is a simple but powerful method to prove theorems, or to simplify proofs in infinite combinatorics. In the first part of the talk, we quickly cover the basic concepts involved for proving results using elementary submodels, and move on to provide two examples of application of the technique to prove two popular results from set theory: The Delta System lemma and the Fodors Pressing down lemma . We provide both the classical proof as well as a proof using elementary submodels to contrast the two approaches.
  
Title: Scott Rank of Computable Codels - Continued
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=== November 16 - Karthik Ravishankar ===
  
=== October 14 - Tejas Bhojraj ===
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Title: Elementary submodels in infinite combinatorics, part II
  
Title: Solovay and Schnorr randomness for infinite sequences of qubits.
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Abstract: In the second part of the talk, we give a proof Fodors Pressing down lemma, along with an overview of the slightly larger proof of the Nash Williams theorem which states that a graph is decomposable as a disjoint union of cycles if and only if it has no odd cut.
  
Abstract : We define Solovay and Schnorr randomness in the quantum setting. We then prove quantum versions of the law of large numbers and of the Shannon McMillan Breiman theorem (only for the iid case) for quantum Schnorr randoms.
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=== Tuesday, November 24 - Tonicha Crook (Swansea University) from 9:00AM-10:00AM ===
  
=== October 21 - Tejas Bhojraj ===
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Title: The Weihrauch Degree of Finding Nash Equilibria in Multiplayer Games
  
Title: Solovay and Schnorr randomness for infinite sequences of qubits.
+
Abstract: Is there an algorithm that takes a game in normal form as input, and outputs a Nash equilibrium? If the payoffs are integers, the answer is yes, and a lot of work has been done in its computational complexity. If the payoffs are permitted to be real numbers, the answer is no, for continuity reasons. It is worthwhile to investigate the precise degree of non-computability (the Weihrauch degree), since knowing the degree entails what other approaches are available (eg, is there a randomized algorithm with positive success change?). The two player case has already been fully classified, but the multiplayer case remains open and is addressed here. As well as some insight into finding the roots of polynomials, which is essential in our research. An in-depth introduction to Weihrauch Reducibility will be included in the presentation, along with a small introduction to Game Theory.
  
=== October 28 - Two short talks ===
+
=== November 30 - Yvette Ren ===
  
Iván Ongay Valverde and James Earnest Hanson
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Title, abstract TBA
 
 
=== November 4 - Two short talks ===
 
 
 
Manlio Valenti and Patrick Nicodemus
 
 
 
=== November 11 - Manlio Valenti I ===
 
 
 
=== November 18 - Manlio Valenti II ===
 
 
 
=== November 25 - Two short talks ===
 
Speakers TBD
 
 
 
=== December 2 - Iván Ongay Valverde I ===
 
 
 
=== December 9 - Iván Ongay Valverde II ===
 
  
 
==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]].

Latest revision as of 10:45, 18 November 2020

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: Mondays 4p-5p (unless stated otherwise)
  • Where: on line (ask for code).
  • 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

Fall 2020 - Tentative schedule

September 14 - Josiah Jacobsen-Grocott

Title: Degrees of points in topological spaces

Abstract: An overview of some results from Takayuki Kihara, Keng Meng Ng, and Arno Pauly in their paper Enumeration Degrees and Non-Metrizable Topology. We will look at a range of topological spaces and the corresponding classes in the enumeration degrees as well as ways in which we can distinguish the type of classes using the separation axioms.

September 28 - James Hanson

Title: The Semilattice of Definable Sets in Continuous Logic

Abstract: After an analysis-free exposition of definable sets in continuous logic, we will present a fun, illustrated proof that any finite bounded lattice can be the poset of definable subsets of $S_1(T)$ for a continuous theory $T$.

October 5 - Tejas Bhojraj from 3:30PM-4:00PM

Title: A Levin-Schnorr type result for Weak Solovay random states.

Abstract: We look at the initial-segment complexity of Weak Solovay quantum random states using MK, a prefix-free version of quantum Kolmogorov complexity. The statement of our result is similar to the Levin-Schnorr theorem in classical algorithmic randomness.

November 9 - Karthik Ravishankar

Title: Elementary submodels in infinite combinatorics

Abstract: The usage of elementary submodels is a simple but powerful method to prove theorems, or to simplify proofs in infinite combinatorics. In the first part of the talk, we quickly cover the basic concepts involved for proving results using elementary submodels, and move on to provide two examples of application of the technique to prove two popular results from set theory: The Delta System lemma and the Fodors Pressing down lemma . We provide both the classical proof as well as a proof using elementary submodels to contrast the two approaches.

November 16 - Karthik Ravishankar

Title: Elementary submodels in infinite combinatorics, part II

Abstract: In the second part of the talk, we give a proof Fodors Pressing down lemma, along with an overview of the slightly larger proof of the Nash Williams theorem which states that a graph is decomposable as a disjoint union of cycles if and only if it has no odd cut.

Tuesday, November 24 - Tonicha Crook (Swansea University) from 9:00AM-10:00AM

Title: The Weihrauch Degree of Finding Nash Equilibria in Multiplayer Games

Abstract: Is there an algorithm that takes a game in normal form as input, and outputs a Nash equilibrium? If the payoffs are integers, the answer is yes, and a lot of work has been done in its computational complexity. If the payoffs are permitted to be real numbers, the answer is no, for continuity reasons. It is worthwhile to investigate the precise degree of non-computability (the Weihrauch degree), since knowing the degree entails what other approaches are available (eg, is there a randomized algorithm with positive success change?). The two player case has already been fully classified, but the multiplayer case remains open and is addressed here. As well as some insight into finding the roots of polynomials, which is essential in our research. An in-depth introduction to Weihrauch Reducibility will be included in the presentation, along with a small introduction to Game Theory.

November 30 - Yvette Ren

Title, abstract TBA

Previous Years

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