Previous Special Year Seminar

Let $f: X \to S$ be a quasi-projective family of varieties defined over $\overline{\mathbb{Q}} \subset \mathbb{C}$. We show that the points of $S(\overline{\mathbb{Q}})$ that are Hodge generic for the variation of Hodge structures associated to $f$...

Using Tougeron’s characterization of multisummable (in the positive real directions) series, the latter can be viewed as infinite series of convergent power series with radii of convergence shrinking to 0. In joint work with Jean-Philippe Rolin and...

Let A be a simple abelian variety, and X and Y be two subvarieties. We say X and Y are in the Bezout range if \dim X + \dim Y >= \dim A, and outside of the Bezout range otherwise. It is known that two varieties in the Bezout range in A always...

A category of motives is an axiomatic framework in which several cohomology theories from algebraic geometry are represented. While Morel and Voevodsky's classical framework of motivic homotopy theory focused on $A^1$-invariant cohomology theories...

I will discuss how the Lang–Trotter conjecture for pairs of elliptic curves implies new cases of the Zilber–Pink conjecture for curves in $\mathcal{A}_3$. Unlike previous results for curves in $\mathcal{A}_g$, our result does not rely on any...

Around 1921 Polya asked about the algebraicity of the indefinite integral of an algebraic function, in terms of the integrality of the coefficients in a power-series expansion. Polya nicely answered the special case of rational functions, using...

The Pila–Zannier strategy has proved to be a particularly fruitful approach: first applied to reprove the Manin–Mumford conjecture, it was later exploited decisively in proofs of the André–Oort conjecture. Crucially relying on a recent counting...

Ideas from tame geometry have recently begun to find their way into quantum field theory and string theory, suggesting that consistent effective theories and their observables may admit definable descriptions of finite complexity. In this talk I...

I will discuss questions pertaining to geometric unlikely intersections and transcendence in the setting of torii in positive characteristic. This is based on work in progress joint with Anup Dixit, Philip Engel, and Ruofan Jiang. 

Every o-minimal structure determines a collection of "tame" or "definable" subsets of $bbR^n$. We can then ask about the fragment of complex geometry present in the structure: Which holomorphic functions are definable, and which spaces are cut out...