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Welcome to Pure Mathematics

We are home to 30 faculty, four staff, approximately 60 graduate students, several research visitors, and numerous undergraduate students. We offer exciting and challenging programs leading to BMath, MMath and PhD degrees. We nurture a very active research environment and are intensely devoted to both ground-breaking research and excellent teaching.


News

Friday, September 29, 2023

Spring 2023 Graduands

Congratulations to Clement Wan, MMath and Eric Boulter, PhD, who convocated in Spring 2023. Best of luck in your future endeavours!

Events

Monday, February 17, 2025 4:00 pm - 4:30 pm EST (GMT -05:00)

Mirror Symmetry Seminar

Kaleb D Ruscitti, University of Waterloo

Yukawa Coupling & the Mirror Map

The mirror map is a choice of co-ordinates on the moduli space of complex deformations Def(X) that come from natural co-ordinates on a moduli space of Kahler structures for X. In this presentation, we aim to introduce this map & the associated Yukawa couplings, in as much detail as possible given only one hour.

MC 2017

Thursday, February 20, 2025 4:00 pm - 5:00 pm EST (GMT -05:00)

Analysis Seminar

Becky Armstrong, Victoria University of Wellington

Analysis Seminar: Twisted groupoids that are not induced by continuous 2-cocycles

Twisted groupoids are generalisations of group extensions that play an important role in C*-algebraic theory: every classifiable C*-algebra has an underlying twisted groupoid model. It is well known that group extensions are in one-to-one correspondence with group 2-cocycles. Analogously, every groupoid 2-cocycle gives rise to a twisted groupoid. However, an example due to Kumjian shows that the converse is not true. Kumjian’s counterexample is a twisted groupoid consisting entirely of isotropy, but in this talk I will present a new example of a twisted groupoid that is not all isotropy, such that the twisted isotropy subgroupoid is not induced by a 2-cocycle. (This is joint work with Abraham C.S. Ng, Aidan Sims, and Yumiao Zhou.)

MC 5417

Monday, February 24, 2025 2:30 pm - 3:30 pm EST (GMT -05:00)

Pure Math Department Colloquium

Carlo Pagano, Concordia University

Hilbert 10 via additive combinatorics

In 1900 Hilbert proposed a list of problems that have been very influential throughout the last century. In 1970 Matiyasevich, building on earlier work of Davis—Putnam—Robinson, proved that Hilbert's 10th problem is undecidable for Z. The problem of extending this result to any ring that is finitely generated over Z (eg ring of integers in number fields) has attracted significant attention since 1970 and, thanks to the efforts of many mathematicians, the task has been reduced to an arithmetic problem about elliptic curves. This problem so far had been solved only conditional on the BSD conjecture (one of the Millenium problems) by Mazur—Rubin.

In joint work with Peter Koymans we have combined additive combinatorics (Green—Tao’s celebrated theorem) with 2-descent (an old technique dating back to Fermat) to solve this problem about elliptic curves unconditionally. This shows that Hilbert 10 is undecidable over any finitely generated infinite commutative ring.

In this colloquium I will provide a gentle introduction to this undecidability result, giving a glimpse of how mathematical logic, number theory and additive combinatorics meet into one story.

MC 5501