The Institute of Advanced Studies, Princeton
In the year 2020, a group of theoretical computer scientists posted a paper on the ArXiv with the strange-looking title "MIP* = RE", impacting and surprising not only complexity theory but also some areas of math and physics. Specifically, it resolved, in the negative, the "Connes' embedding conjecture" in the area of von Neumann algebras, and the "Tsirelson problem" in quantum information theory. You can find the paper here. As it happens, both acronyms MIP* and RE represent proof systems, of a very different nature. To explain them, we'll take a meandering journey through the classical and modern definitions of proof. I hope to explain how the methodology of computational complexity theory, especially modeling and classification (both problems and proofs) by algorithmic efficiency, naturally leads to the generation of new such notions and results (and more acronyms, like NP). A special focus will be on notions of proof which allow interaction, randomness, and errors, and their surprising power and magical properties. This talk requires no special background.
At 16:30 in AulaC03 of the Università degli Studi di Milano, via Mangiagalli 25
Columbia University, New York
The isoperimetric inequality has a long history in mathematics. In this lecture, we will discuss how the isoperimetric inequality can be generalized to submanifolds in Euclidean space. As a special case, we obtain a sharp isoperimetric inequality for minimal submanifolds of codimension at most 2, answering a question going back to work of Carleman. The proof of that inequality is inspired by, but does not actually use, optimal transport.
At 16:30 in Aula T.1.1 (first floor) in the Edificio 13 (Trifoglio) of the Politecnico di Milano, via Bonardi 9
University of Toronto
Shimura Varieties are higher dimensional analogues of modular curves, and they play a foundational role in modern number theory. The most familiar Shimura varieties are the moduli spaces of Abelian varieties, and in this context we have a wealth of diophantine results, both in the number field and function field setting: Finiteness of S-rational points, the Tate conjecture, the Shafarevich conjecture, semisimplicity of Galois representations, and others. We focus on the exceptional setting for Shimura varieties, where the lack of a moduli interpretation makes matters more difficult. We explain some analogues of the aforementioned results. Crucial to this is the existence of canonical integral models, which we construct at almost all primes. This is joint work with Ben Bakker and Ananth Shankar.
At 16:30 in Aula Sironi of the Università di Milano-Bicocca, Edificio U4-Tellus, Piazza della Scienza 4