## Matthias Hamann (02/10/15)

Math Colloquium

### Speaker: Matthias Hamann

Title: Accessible groups and graphs

Location: V-157, VRII.

Time: Friday, October 2, at 15:00-16:00.

### Abstract:

The talk falls into two parts. First, we give an overview of the group theoretical concept of accessibility and the main results in this area.

In the second part, we define the graph theoretical notion of accessibility. After a brief discussion of the connection of these two kinds of accessibility, we reinterpret the mentioned group theoretic theorems graph theoretically. This leads to many new questions some of which are solved and others are widely open.