Seminars and Colloquia Schedule

Quantum torus methods for Kauffman bracket skein modules

Series
Dissertation Defense
Time
Friday, July 26, 2019 - 10:00 for 1 hour (actually 50 minutes)
Location
Skiles 114
Speaker
Jonathan PaprockiGeorgia Institute of Technology

We investigate aspects of Kauffman bracket skein algebras of surfaces and modules of 3-manifolds using quantum torus methods. These methods come in two flavors: embedding the skein algebra into a quantum torus related to quantum Teichmuller space, or filtering the algebra and obtaining an associated graded algebra that is a monomial subalgebra of a quantum torus. We utilize the former method to generalize the Chebyshev homomorphism of Bonahon and Wong between skein algebras of surfaces to a Chebyshev-Frobenius homomorphism between skein modules of marked 3-manifolds, in the course of which we define a surgery theory, and whose image we show is either transparent or (skew)-transparent. The latter method is used to show that skein algebras of surfaces are maximal orders, which implies a refined unicity theorem, shows that SL_2C-character varieties are normal, and suggests a conjecture on how this result may be utilized for topological quantum compiling.

Compactness and singularity related to harmonic maps

Series
PDE Seminar
Time
Friday, July 26, 2019 - 13:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Jiayu LiUniversity of Science and Technology of China

In this talk we will review compactness results and singularity theorems related to harmonic maps. We first talk about maps from Riemann surfaces with tension fields bounded in a local Hardy space, then talk about stationary harmonic maps from higher dimensional manifolds, finally talk about heat flow of harmonic maps.