### Bounds on sums of graph eigenvalues

- Series
- Math Physics Seminar
- Time
- Friday, February 1, 2013 - 16:00 for 1 hour (actually 50 minutes)
- Location
- Skiles 006
- Speaker
- Evans Harrell – Georgia Tech – harrell@math.gatech.edu

I'll discuss two methods for finding bounds on sums of graph eigenvalues (variously for the Laplacian, the renormalized Laplacian, or the adjacency matrix). One of these relies on a Chebyshev-type estimate of the statistics of a subsample of an ordered sequence, and the other is an adaptation of a variational argument used by P. Kröger for Neumann Laplacians. Some of the inequalities are sharp in suitable senses. This is ongoing work with J. Stubbe of EPFL