## Making Reality Disappear: The Trump Administration and International Realtions

Klaus Larres

January 27, 2017

followed by a Member talk and dinner with spouses at 7:00 p.m.

Klaus Larres

January 27, 2017

followed by a Member talk and dinner with spouses at 7:00 p.m.

Aaron Roth

University of Pennsylvania

January 30, 2017

In this talk, I will discuss our recent efforts to formalize a particular notion of “fairness” in online decision making problems, and study its costs on the achievable learning rate of the algorithm. Our focus for most of the talk will be on the “contextual bandit” problem, which models the following scenario. Every day, applicants from different populations submit loan applications to a lender, who must select a subset of them to give loans to.

Timothy Perutz

University of Texas, Austin; von Neumann Fellow, School of Mathematics

January 30, 2017

I'll describe joint work with Sheel Ganatra and Nick Sheridan which rigorously establishes the relationship between different aspects of the mirror symmetry phenomenon for Calabi-Yau manifolds. Homological mirror symmetry---an abstract, categorical statement---implies Hodge theoretic mirror symmetry, a concrete relation between counts of rational curves and variations of Hodge structure.

Ailsa Keating

Member, School of Mathematics

January 30, 2017

Dhruv Ranganathan

Member, School of Mathematics

January 30, 2017

Tony Yue Yu

Member, School of Mathematics

January 30, 2017

Alex Andoni

Columbia University

January 31, 2017

Dmitry Orlov

Steklov Mathematical Institute, Russian Academy of Sciences; Member, School of Mathematics

February 1, 2017

We are will discuss a notion of noncommutative and derived algebraic variety. This approach comes from a generalization of derived categories of (quasi)coherent sheaves on usual algebraic varieties and their enhancements. We are going to talk about different properties of noncommutative varieties such as regularity, smoothness and properness. A new operation of gluing of noncommutative varieties will be introduced.

Sara Tukachinsky

University of Montreal

February 2, 2017

The standard WDVV equations are PDEs in the potential function that generates Gromov-Witten invariants. These equations imply relations on the invariants, and sometimes allow computations thereof, as demonstrated by Kontsevich-Manin (1994). We prove analogous equations for open Gromov-Witten invariants that we defined in a previous work. For ($\mathbb CP^n$ ,$\mathbb RP^n$), the resulting relations allow the computation of all invariants. The formulation of the open WDVV requires a lift of the big quantum product to relative cohomology.

Dmitry Orlov

Steklov Mathematical Institute, Russian Academy of Sciences; Member, School of Mathematics

February 3, 2017

We are will discuss a notion of noncommutative and derived algebraic variety. This approach comes from a generalization of derived categories of (quasi)coherent sheaves on usual algebraic varieties and their enhancements. We are going to talk about different properties of noncommutative varieties such as regularity, smoothness and properness. A new operation of gluing of noncommutative varieties will be introduced.