## Some Arithmetic Path Integrals

Minhyong Kim

Oxford University

April 3, 2019

Costante Bellettini

Princeton University; Member, School of Mathematics

April 2, 2019

In recent works with N. Wickramasekera we develop a regularity and compactness theory for stable hypersurfaces (technically, integral varifolds) whose generalized mean curvature is prescribed by a (smooth enough) function on the ambient Riemannian manifold. I will describe the relevance of the theory to analytic and geometric problems, and describe some GMT and PDE aspects of the proofs.

Projit Bihari Mukharji

University of Pennsylvania

April 2, 2019

Ben Filippenko

University of California, Berkeley

April 1, 2019

Liam McAllister

Cornell University

April 1, 2019

Li-Yang Tan

Stanford University

April 1, 2019

We give a pseudorandom generator that fools $m$-facet polytopes over $\{0,1\}^n$ with seed length $\mathrm{polylog}(m) \cdot \mathrm{log}(n)$. The previous best seed length had superlinear dependence on $m$. An immediate consequence is a deterministic quasipolynomial time algorithm for approximating the number of solutions to any $\{0,1\}$-integer program. Joint work with Ryan O'Donnell and Rocco Servedio.

Viswambhara Makam

Member, School of Mathematics

April 1, 2019

Invariant theory is a fundamental subject in mathematics, and is potentially applicable whenever there is symmetry at hand (group actions). In recent years, new problems and conjectures inspired by complexity have come to light. In this talk, I will describe some of these new problems, and discuss some positive and negative results regarding them.

Xin Zhou

University of California, Santa Barbara; Member, School of Mathematics

March 27, 2019

I will present a proof with some substantial details of the Multiplicity One Conjecture in Min-max theory, raised by Marques and Neves. It says that in a closed manifold of dimension between 3 and 7 with a bumpy metric, the min-max minimal hypersurfaces associated with the volume spectrum introduced by Gromov, Guth, Marques-Neves are all two-sided and have multiplicity one.

Matthew Stover

Temple University

March 27, 2019

Abstract: I will survey (in)coherence of lattices in semisimple Lie groups, with a view toward open problems and connections with the geometry of locally symmetric spaces. Particular focus will be placed on rank one lattices, where I will discuss connections with reflection groups, "algebraic" fibrations of lattices, and analogies with classical low-dimensional topology.

Patricia Clavin

March 27, 2019