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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

More than 100 researchers and students from across Canada and around the world attended the 53rd annual Canadian Operator Algebras Symposium (COSY), which took place from May 26-30 at the University of Waterloo.

Events

Thursday, February 19, 2026 11:00 am - 12:00 pm EST (GMT -05:00)

Algebraic geometry working seminar

Catherine St-Pierre, University of Waterloo

Why does the Spec functor not extend to non-commutative rings?

The functor Spec, which assigns to a commutative ring its prime spectrum, plays a central role in algebraicgeometry. A natural question is whether this construction can be extended in a meaningful way tononcommutative rings. In this talk, we discuss the obstruction to the extension of the functor Spec to non-commutative rings presented by Manuel L. Reyes, showing that any functor extending Spec and satisfyingreasonable compatibility conditions must collapse on certain noncommutative rings, such as matrix algebras$M_3(\mathbb C)$.

MC 5417

Monday, February 23, 2026 2:30 pm - 3:30 pm EST (GMT -05:00)

Pure Math Colloquium

Tommaso Pacini, University of Torino

Kahler techniques beyond Kahler geometry: the case of pluripotential theory

Classical pluripotential theory was introduced into complex analysis in the 1940's, as an analogue of the theory of convex functions. In the early 2000's, Harvey and Lawson showed that both pluripotential theory and many of its analytic applications make sense in a much broader setting.

Starting with the work of Calabi in the 1950's, however, it has become clear that pluripotential theory is central also to Kahler geometry. In particular, it is closely related to the cohomology of Kahler manifolds via Hodge theory and the ddbar lemma, and it provides one of the main ingredients in proving the existence of canonical metrics.

Work in progress, joint with A. Raffero, shows how parts of this "second life" of pluripotential theory extend to other geometries, hinting towards new research directions in the field of calibrated geometry and manifolds with special holonomy.

The goal of this talk will be to present a non-technical overview of some of these topics, aimed at non-specialists.

MC 5501

Tuesday, February 24, 2026 10:00 am - 11:00 am EST (GMT -05:00)

Number Theory Seminar

Chi Hoi Yip, Georgia Institute of Technology

Inverse sieve problems

Many problems in number theory boil down to bounding the size of a set contained in a certain set of residue classes mod p for various sets of primes p; and then sieve methods are the primary tools for doing so. Motivated by the inverse Goldbach problem, Green–Harper, Helfgott–Venkatesh, Shao, and Walsh have explored the inverse sieve problem: if we let S \subseteq N be a maximal set of integers in this interval where the residue classes mod p occupied by S have some particular pattern for many primesp, what can one say about the structure of the set S beyond just its size? In this talk, I will give a gentle introduction to inverse sieve problems, and present some progress we made when S mod p has rich additive structure for many primes p. In particular, in this setting, we provide several improvements on the larger sieve bound for |S|, parallel to the work of Green--Harper and Shao for improvements on the large sieve. Joint work with Ernie Croot and Junzhe Mao.

MC 5479 or Join on Zoom