## Events

Nov 7

### Mathematics and Statistics Colloquium

Two 30-minute colloquium talks by graduate students from Iowa State.

Thursday, November 7th, 2019

4:00 – 5:00 pm / CMC 206

**Mary Vaughan**

Title: What is a fractional derivative?

Abstract:The notion of fractional calculus was first mentioned around the birth of classical calculus, but it was not until the 1800s that the foundations were set. After a brief discussion of the usual derivative, we will motivate and define the Marchaud fractional derivative. Then, we will discuss how the non-local, one-sided properties of fractional derivatives can be used to capture memory effects in models and, if time permits, how they appear naturally in mechanics.

Title: What is a fractional derivative?

Abstract:

**Kate Lorenzen**

Title: Two graphs, one spectrum

Abstract:Graphs look at objects (vertices) and connections between them (edges). We can associate a graph with a matrix by indexing our rows and columns by the vertices and storing a value in the entry (for example, we can have a value of 1 if our vertices are connected, and a 0 otherwise). Once we have a matrix, we can find its set of eigenvalues (spectrum) which contains some information about the graph. We will overview several different matrices associated with a graph and families of graphs that have the same spectrum.

Title: Two graphs, one spectrum

Abstract:

Sponsored by Mathematics and Statistics Events. Contact: Sue Jandro