Events

Andrej Vukovic, Department of Pure Mathematics, University of Waterloo

We review aspects of the theory of Berkovich spaces, including quasimonomial valuations and invariants associated to a valuation. We then discuss birational geometry, introducing blowups and log resolutions of ideals. We discuss dual graphs and describe the classification of semivaluations in the valuative tree. We conclude by returning to our earlier study of plane polynomial dynamics.

M3 3103

Hayley Reid, Department of Pure Mathematics, University of Waterloo

"Cutting a square into triangles of equal area"

Luke MacLean, Department of Pure Mathematics, University of Waterloo

"Reverse Mathematics"

We say that $S \subseteq \mathcal{P}(\omega)$ is an $\omega$-model of a subsystem of second order arithmetic if the $L_2$ structure $(\omega, S, +, \cdot, 0, 1, <)$ correctly models the subsystem in question. The goal of this lecture will be to prove that there is an $\omega$-model of $WKL_0$ consisting entirely of low sets. 

This will involve learning about PA degrees and the low basis theorem.

All are welcome.

MC 5413

Andrej Vukovic, Department of Pure Mathematics, University of Waterloo

We continue where last week's discussion left off by discussing the classification of semivaluations in the valuative tree. Then we return to our study of plane polynomial dynamics.

M3 3103

Alexandru Nica, Department of Pure Mathematics, University of Waterloo

"Free probabilistic aspects of meandric systems"

Wilson Poulter, Department of Pure Mathematics, University of Waterloo

"NIP VI"

We finish section 2.2.2 of Simon's Guide to NIP theories and move on to 2.2.3.

MC 5413

Arpita Kar, Queen's University

"Some reflections on the Riemann Hypothesis"

Dino Rossegger, Department of Pure Mathematics, University of Waterloo

"Determinacy in second order arithmetic"

Daniel Le, University of Toronto

Boyu Li, University of Victoria

"Amenable and Non-amenable Semigroups"

Since Nica introduced the notion of amenability of quasi-lattice ordered semigroups, the amenability for many classes of semigroups remain unanswered. We will give a brief overview of semigroup amenability, and show some recent developments on this topic using dilation theory. In particular, we shall show that Artin monoids are non-amenable except the class of right-angled. This is a joint work with Marcelo Laca.

MC 5417