# Events for 10/22/2019 from all calendars

## Analysis/PDE Reading Seminar

**Time: ** 4:00PM - 5:00PM

**Location: ** BLOC 624

**Speaker: **Gregory Berkolaiko, Texas A&M University

**Title: ***Self-adjoint extensions via boundary triples (part II)*

**Abstract: **To better understand self-adjoint extensions of symmetric operators via boundary triples (and associated topics such as Krein resolvent formula), we will consider how this theory works for matrices. The analog of a symmetric operator is a rectangular matrix. Because its domain isn't dense, its adjoint is not a matrix but must be interpreted as a linear relation. With this understanding, the rest of the theory follows. Some interesting links emerge, for example the Dirichlet-to-Neumann map is a Schur complement in the matrix case.

In the first part we reviewed the general theory. In the second we will play with the simple example of linear
operators on C^3 (i.e. 3x3 matrices).

## Student Working Seminar in Category Theory

**Time: ** 5:00PM - 6:00PM

**Location: ** BLOC 506A

**Speaker: **Zheng Kuang

**Title: ***The Yoneda Lemma (Riehl 2.2)*

**Abstract: **We will prove Yondeda Lemma and introduce some of its consequences.