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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

Tuesday, April 7, 2026 10:00 am - 1:00 pm EDT (GMT -04:00)

PhD Thesis Defense

Xiao Zhong, University of Waterloo

Topics in Arithmetic Dynamics

This thesis studies several problems in arithmetic dynamics, focusing on preimages of invariant subvarieties,common zeros of iterates of rational functions, and periodic curves for polynomial endomorphisms. Weinvestigate stabilization phenomena for rational points in backward orbits and develop dynamical cancellationresults for semigroups of polynomials. We also prove a finiteness theorem for common zeros of iterates ofcompositionally independent rational functions, answering a question of Hsia and Tucker. Finally, we studypolynomial endomorphisms of the projective plane with many periodic curves, showing that families containinga Zariski dense set of periodic curves must be invariant under an iterate, and we classify maps admittinginfinitely many periodic curves of bounded degree.

MC 5479

Tuesday, April 7, 2026 10:00 am - 11:00 am EDT (GMT -04:00)

Number Theory Seminar

Ila Varma, University of Toronto

Counting Number Fields by P^1 height

When do two irreducible polynomials with integer coefficients define the same number field? One can define an action of GL_2 × GL_1 on the space of polynomials of degree n so that for any two polynomials f and g in the same orbit, the roots of f may be expressed as rational linear transformations of the roots of g; thus, they generate the same field. In this article, we show that almost all polynomials of degree n with size at most X can only define the same number field as another polynomial of degree n with size at most X if they lie in the same orbit for this group action. (Here we measure the size of polynomials by the greatest absolute value of their coefficients.)

This improves on work of Bhargava, Shankar, and Wang, who proved a similar statement for a positive proportion of polynomials. Using this result, we prove that the number of degree n fields such that the smallest polynomial defining the field has size at most X is asymptotic to a constant times X^{n+1} as long as n \ge 3. For n = 2, we obtain a precise asymptotic of the form 27/(pi^2) * X^2

This is joint work with Arango-Pineros, Gundlach, Lemke Oliver, McGown, Sawin, Serrano Lopez, and Shankar.

MC 5479

Tuesday, April 7, 2026 4:00 pm - 5:00 pm EDT (GMT -04:00)

Model Theory Working Seminar

Jules Ribolzi, University of Waterloo

A Chevalley structure theorem for meromorphic groups

We continue to study definable groups in the standard model of CCM. We will look at the proof of a Chevalleystructure type theorem for meromorphic groups (that is, meromorphic groups are regular in the sense of Fujiki)from the article of Pillay and Scanlon.

MC 5479