# TBA

## Speaker:

## Institution:

## Time:

## Location:

A joint seminar with the Geometry & Topology Seminar series.

Jianfeng Lin

UC San Diego

Tuesday, October 1, 2019 - 4:00pm

RH 306

A joint seminar with the Geometry & Topology Seminar series.

Paula Burkhardt-Guim

UC Berkeley

Tuesday, October 15, 2019 - 4:00pm

RH306

Ao Sun

MIT

Friday, November 8, 2019 - 4:00pm to 5:00pm

RH 306

Xi-Ping Zhu

Sun Yat-sen University

Tuesday, August 6, 2019 - 4:00pm

RH 306

The well-known Yau’s uniformization conjecture states that any

complete noncompact Kaehler manifold with positive bisectional curvature is

bi-holomorphic to the complex Euclidean space. The conjecture for the case

of maximal volume growth has been recently confirmed by G. Liu. In this

talk, we will consider the conjecture for manifolds with non-maximal volume

growth. We will show that the finiteness of the first Chern number is an

essential condition to solve Yau’s conjecture by using algebraic embedding

method. Furthermore, we can verify the finiteness in the case of minimal

volume growth. In particular, we obtain a partial answer to Yau’s

uniformization conjecture on complex two-dimensional Kaehler manifolds with

minimal volume growth. This is a joint work with Bing-Long Chen.

David Krejcirik

Czech Technical University in Prague

Tuesday, June 25, 2019 - 4:00pm

RH 306

According to the conjecture of Rauch’s from 1974, any eigenfunction corresponding to the principal eigenvalue of the Neumann Laplacian attains its extrema on the boundary of planar domains. After giving an account on the history and validity of the conjecture, we present our own new results for tubular neighbourhoods of curves on surfaces. This is joint work with Matej Tusek.

Yongjia Zhang

UC San Diego

Tuesday, May 21, 2019 - 4:00pm

RH 306

Entropy has been an important topic in the study of Ricci flow

ever since it was invented by Perelman. We consider Perelman's entropy

defined on an ancient solution, and prove a gap theorem for its backward

limit: If Perelman's entropy limits to a number too close to zero as time

approaches negative infinity, then the ancient solution must be the trivial

Euclidean space.

Joint seminar

Tuesday, June 4, 2019 - 4:00pm to 6:00pm

UC Riverside Skye 347

Location: Skye Hall 347

4:00-4:50pm

Speaker: Yu-Shen Lin (Boston University)

Title: Special Lagrangian fibrations in weak Del Pezzo Surfaces

Abstract: Motivated by the study of mirror symmetry, Strominger-Yau-Zaslow (SYZ) conjectured that Calabi-Yau manifolds admit certain minimal Lagrangian fibrations. These minimal Lagrangians are the special Lagrangian submanifolds studied earlier by Harvey-Lawson. Many of the implication of the SYZ conjecture is proved and it has been the guiding principle for studying mirror symmetry for a long time. However, not many special Lagrangians are known in the literature. In this talk, I will prove the existence of special Lagrangian fibration on the complement of a smooth anti-canonical divisor in a (weak) Del Pezzo surface. If the time allows, I will explain its impact to mirror symmetry. This is joint work with Tristan Collins and Adam Jacob.

5:00-5:50pm

Speaker: Yannis Angelopoulos (UCLA)

Title: Linear and nonlinear waves on extremal Reissner-Nordstrom spacetimes

Abstract: I will present several results (that have been obtained jointly with Stefanos Aretakis and Dejan Gajic) from the analysis of solutions of linear and nonlinear wave equations on extremal Reissner-Nordstrom spacetimes, including sharp asymptotics on the horizon and at infinity for linear waves, and instability phenomena for nonlinear waves. These results can be seen as stepping stones to the fully nonlinear problem of stability/instability of extremal black holes.

Mat Langford

University of Tennessee

Tuesday, April 9, 2019 - 4:00pm

RH 306

A deep result of X.-J. Wang states that a convex ancient solution to mean curvature flow either sweeps out all of space or lies in a stationary slab (the region between two fixed parallel hyperplanes). We will describe recent results on the construction and classification of convex ancient solutions and convex translating solutions to mean curvature flow which lie in slab regions, highlighting the connection between the two. Work is joint with Theodora Bourni and Giuseppe Tinaglia.

Fei Han

National University of Singapore

Tuesday, June 11, 2019 - 4:00pm to 5:00pm

Nicos Kapouleas

Brown University

Tuesday, April 16, 2019 - 4:00pm

RH 306

I will discuss some recent work with David

Wiygul to determine the index and nullity of the

Lawson surfaces desingularizing two orthogonal

great two-spheres in the round three-sphere.