# Events - 2017

Tuesday, December 5, 2017 — 2:30 PM EST

## Computability Learning Seminar

Mohammad Mahmoud, Department of Pure Mathematics, University of Waterloo

"Borel Reducibility and Linear Orderings"

We define Borel reducibility introduced by Friedman and Stanley between classes of countable structures. We will define what it means for a class of structures to be complete with respect to Borel reducibility and then we will go through their proof of the fact that the class of countable linear orderings is complete with respect to Borel reducibility.

MC 5413

Friday, December 1, 2017 — 2:30 PM EST

## Geometry & Topology Seminar

Ákos Nagy, University of Waterloo and The Fields Institute

"Vortex-like instantons on the Euclidean Schwarzschild manifold"

Thursday, November 30, 2017 — 1:30 PM EST

## Number Theory Seminar

Simon Myerson, University College London

"Forms in many variables: an iterative approach"

Wednesday, November 29, 2017 — 4:45 PM EST

Jitendra Prakash, Department of Pure Mathematics, University of Waterloo

"Bell's Theorem"

Bell's theorem is one of the celebrated cornerstones in physics, being described as "the most profound discovery of science". In this talk we shall discuss this theorem from a mathematical perspective, and as an example we shall derive the CHSH inequality. We shall also see what more general questions this theorem raises. Knowledge of physics is not required, however some basic linear algebra will be used.

MC 5501

Tuesday, November 28, 2017 — 4:00 PM EST

## Model Theory Seminar

Tuesday, November 28, 2017 — 1:30 PM EST

## Algebraic Geometry Learning Seminar

Nickolas Rollick, Department of Pure Mathematics, University of Waterloo

"Definitions are relative"

Having spent the last two weeks on algebraic preliminaries, we now take a sharp right turn to explore the scenic route to our destination.  Specifically, we will see how to "relativize" the notions of quasicompactness and quasiseparatedness, to make them properties of morphisms rather than properties of schemes.  Along the way, we verify as much as possible that these classes of morphisms are good ones in the sense of Vakil.

MC 5413

Friday, November 24, 2017 — 3:30 PM EST

## Analysis Seminar

Arthur Mehta, Department of Pure Mathematics, University of Waterloo

"Chromatic numbers and a Lovász type inequality for non-commutative graphs"

Friday, November 24, 2017 — 2:30 PM EST

## Geometry & Topology Seminar

Xinliang An, University of Toronto

"On Singularity Formation in General Relativity"

Thursday, November 23, 2017 — 1:30 PM EST

## Number Theory Seminar

Divyum Sharma, Department of Pure Mathematics, University of Waterloo

"Joint distribution of the base-q and Ostrowski digital sums"

Wednesday, November 22, 2017 — 4:30 PM EST

Mehdi Karimi, Department of Combinatorics & Optimization, University of Waterloo

"Sum-of-Squares Proofs in Optimization"

The old concept of sum-of-squares found its way into optimization and even machine learning. I will talk about this quickly evolving research area known as convex algebraic geometry.

MC 5501

Tuesday, November 21, 2017 — 4:00 PM EST

## Model Theory Seminar

"Residue field domination in theories of valued fields"

Tuesday, November 21, 2017 — 2:30 PM EST

## Computability Learning Seminar

Michael Deveau, Department of Pure Mathematics, University of Waterloo

"Isomorphisms that cannot be coded by computable relations -- Part 2"

Last time, we saw why it is so useful to code an isomorphism by the image of a computable relation and also explored some cases where this is always possible. We now turn to constructing a pair of structures where this is not possible. That is, we construct two structures -- isomorphic to $(\omega, <)$ -- where this method of establishing the degree of the isomorphism between them will not work.

MC 5413

Tuesday, November 21, 2017 — 1:30 PM EST

## Algebraic Geometry Learning Seminar

Parham Hamidi, Department of Pure Mathematics, University of Waterloo

"Integral advice on going up in the world1!"

Now that we are done with definitions and a few boring results about integral homomorphisms, we can prove the Lying over and Going up Theorems. I will prove Nakayama’s Lemma using a simple trick and talk about some of its applications. Finally we would see how the Lying over and Going up Theorems can be interpreted geometrically in number theory in the theory of ramifications.

Monday, November 20, 2017 — 4:00 PM EST

## Pure Math Colloquium

Alexei Oblomkov, University of Massachusetts

"Planar curve singularities, knot invariants and representation theory"

Friday, November 17, 2017 — 3:30 PM EST

## Analysis Seminar

Paul Skoufranis, York University

"Bi-Free Versions of Entropy"

Friday, November 17, 2017 — 2:30 PM EST

## Geometry & Topology Seminar

Eric Woolgar, University of Alberta

"Curvature-dimension conditions in relativity and Lorentzian geometry"

Thursday, November 16, 2017 — 3:30 PM EST

## Universal Algebra Seminar

Renzhi Song, Department of Pure Mathematics, University of Waterloo

"Series parallel posets and polymorphisms, part 2"

In this two part series I will talk about the poset retraction problem on the class of series parallel posets. Having classified those series-parallel posets whose retraction problem can be solved in polynomial time, I will now show that these same posets admit what is known as SD-join polymorphisms. Equivalently, their retraction problems are in nondeterministic log space.

MC 5413

Thursday, November 16, 2017 — 1:30 PM EST

## Number Theory Seminar

"On an extension of the Landau-Gonek formula"

Wednesday, November 15, 2017 — 3:30 PM EST

## Algebra Seminar

Rita Gitik, University of Michigan

"A New Algorithm in Group Theory"

We describe a new algorithm which determines if the intersection of a quasiconvex subgroup of a negatively curved group with any of its conjugates is infinite. The algorithm is based on the concepts of a coset graph and a geodesic core of a subgroup. This algorithm is utilized in several other new algorithms computing breadth, height, and width of a quasiconvex subgroup of a negatively curved group.

MC 5403

Tuesday, November 14, 2017 — 4:00 PM EST

## Model Theory Seminar

Christopher Hawthorne, Department of Pure Mathematics, University of Waterloo

"Qualitative probability theory and types, part 2"

We continue Tao's blog post; we define random variables, and we examine qualitative probability measures on definable sets. Time permitting, we study random variables on groups and the group chunk theorem.

MC 5403

Tuesday, November 14, 2017 — 1:30 PM EST

## Algebraic Geometry Learning Seminar

Parham Hamidi, Department of Pure Mathematics, University of Waterloo

"Bermuda, Bahama, come on Nakayama1!"

Monday, November 13, 2017 — 4:00 PM EST

## Pure Math Colloquium

Kevin Costello, Perimeter Institute

"An introduction to the AdS/CFT correspondence for mathematicians"

The AdS/CFT correspondence has been of central importance in theoretical physics for the past 10 years.  It is a correspondence between conformal field theories in d dimensions and gravity in d + 1 dimensions.

This talk will be an attempt to introduce this topic to a mathematical audience. No previous knowledge of conformal field theory will be assumed.

MC 5501

Friday, November 10, 2017 — 3:30 PM EST

## Analysis Seminar

Jitendra Prakash, Department of Pure Mathematics, University of Waterloo

"Non-closure of the set of quantum correlations"

Friday, November 10, 2017 — 2:30 PM EST

## Geometry & Topology Seminar

Yoav Len, Department of Combinatorics & Optimization, University of Waterloo

"Tangent lines and the equation 28=7 x 4"

Thursday, November 9, 2017 — 3:30 PM EST

## Universal Algebra Seminar

Renzhi Song, Department of Pure Mathematics, University of Waterloo

"Series parallel posets and polymorphisms"

In this two part series I will talk about the poset retraction problem on the class of series parallel posets. In this talk I will make introductions on series parallel posets and define what a polymorphism is and how their existence affects the complexity of the poset retraction problem.

MC 5413

## Pages

### January 2017

S M T W T F S
1
2
3
4
5
6
7
8
14
15
21
22
28
29
1
2
3
4
1. 2023 (112)
1. April (1)
2. March (51)
3. February (33)
4. January (27)
2. 2022 (179)
1. December (8)
2. November (31)
3. October (24)
4. September (17)
5. August (9)
6. July (15)
7. June (14)
8. May (13)
9. April (14)
10. March (15)
11. February (12)
12. January (7)
3. 2021 (135)
4. 2020 (103)
5. 2019 (199)
6. 2018 (212)
7. 2017 (281)
1. December (2)
2. November (33)
3. October (34)
4. September (16)
5. August (3)
6. July (17)
7. June (26)
8. May (27)
9. April (14)
10. March (38)
11. February (42)
12. January (29)
8. 2016 (335)
9. 2015 (211)
10. 2014 (235)
11. 2013 (251)
12. 2012 (135)