Seminars & Colloquia Calendar
Using rectangular convolutions to construct biregular expanders
Adam Marcus, Princeton University
Location: Hill 705
Date & time: Monday, 12 February 2018 at 2:00PM - 3:00PM
Abstract: I will discuss recent advances in the technique we call "the method
of interlacing polynomials'' --- a technique that uses polynomials as
a way to prove existence theorems in linear algebra. Previous results
used this method to show the existence of bipartite Ramanujan graphs
of any size and degree, and subsequent progress was made in the work
of Cohen in the form of a polynomial time construction. This talk
will discuss some recent progress in extending these results to the
case of biregular, bipartite expanders. Unlike classical Ramanujan
graphs, these new constructions can have partitions of different
sizes, making them more suitable for many applications.
This is joint work with Aurelien Gribinski.