Events

Wilson Poulter, Department of Pure Mathematics, University of Waterloo

"Ultraproducts, Hyperreals, and Pseudofinite Graphs"

An ultraproduct is a construction used in mathematical logic to construct limits of first-order structures. Due to a result of Jerzy Los, the first-order properties of these limits is very well understood, allowing one to construct counter-examples as well as structures that are interesting in and of themselves.

Michael Klug, University of California Berkeley

"Concordance of homotopic spheres in 4-manifolds"

Alex Rutar, Department of Pure Mathematics, University of Waterloo

"Geometric and Combinatorial Separation Conditions for Iterated Function Systems"

Ilan Hirshberg, Ben Gurion University of the Negev

"Mean dimension and radius of comparison"

Hongdi Huang, Department of Pure Mathematics, University of Waterloo

In the half part, we will complete the leftover on the generators and relations. Then we will setup for Frobenius algebras. Finally, we will go-ahead to the algebra structure. 

MC 5417

Wilson Poulter, Department of Pure Mathematics, University of Waterloo

"NIP XIII"

We continue section 4.1 of Simon's Guide to NIP theories.

MC 5479

Sacha Mangarel, Centre de Recherches Mathématiques

"On Low Discrepancy Multiplicative Sequences"

Luke MacLean, Department of Pure Mathematics, University of Waterloo

"Kleene's $\mathcal{O}$"

Kleene's $\mathcal{O}$ is a system for ordinal notation used in computability theory that relates the concepts of constructive and computable ordinals. This notation allows one to unambiguously perform transfinite induction on ordinals by ensuring that there is a unique representation for each ordinal.

We will prove some properties about the notation system and show that there are ordinals which are not computable.

MC 5413

Rahim Moosa, Department of Pure Mathematics, University of Waterloo

"Dynamics on the Berkovich line"

I will discuss how algebraic dynamics on the affine or projective line extend to the Berkovich  line. My aim is Theorem 4.7 of Jonsson's notes.

MC 5403

Gavin Ball, Université du Québec à Montréal and Centre de recherches mathématiques

"Closed G2-structures inducing a conformally flat metric"