About me

I am currently an assistant professor in Discrete Mathematics at the Korteweg-de Vries Institute for Mathematics, at University of Amsterdam. I work in algebraic graph theory. My background is in eigenvalues of graphs and digraphs, graph polynomials, association schemes, and linear algebra. I am interested in studying these areas, and also in using tools from these areas in new settings, such as quantum computing and optimization. I am also a member of QuSoft.  

Starting in March 2022, I serve as a Managing Editor of the Electronic Journal of Combinatorics. Amsterdam has a very active research community; for more information see TCS (Theoretical Computer Science) Amsterdam and DIAMANT

Eni Musta, Jeroen Zuiddam and I organize the General Mathematics Colloquium at the University of Amsterdam.

Here is my curriculum vitae and my Google Scholar
My email is k dot last name at uva dot nl. 

I sometimes write expository articles on mathematics that I would like to understand better in the Graphs on Napkins section of this website. Here’s a video of me  explaining my thesis topic in 3 minutes, as a part of SFU’s 3MT thesis competition in 2013, in which I was a finalist. I sometimes report on my coffee and math adventures on twitter and on Mastodon

I use SageMath as a way to generate examples and gain intuition; a while ago, I gave a tutorial on casual uses of SageMath in research. Here is my github, including a repository of cubic vertex-transitive graphs (it is the graph6 string version of the census of Primož Potočnik, Pablo Spiga, and Gabriel Verret). 

Krystal Guo


Background: education and previous positions

From October 2019 to August 2020, I was a post-doctoral fellow at Université de Montréal and Centre de Recherches Mathématiques, supervised by Luc Vinet.  From September 2017 to August 2019, I was a post-doctoral fellow at Université libre de Bruxelles with Samuel Fiorini. I was a visiting scholar at the Simons Institute for the Theory of Computing at UC Berkeley, from September 1 to November 1, 2017.  From September 2015 to August 2017, I was a post-doc at University of Waterloo with Chris Godsil. 

I completed my Ph.D. in Mathematics at Simon Fraser University on (2011 – January 26, 2015) under the supervision of Bojan Mohar. The title of my thesis is “Simple eigenvalues of graphs and digraphs”. I completed my Masters of Mathematics (2009-2010) at University of Waterloo in Combinatorics & Optimization, under the supervision of  Chris Godsil. My undergraduate degree (2004-2009) is also from University of Waterloo. I have a double major in pure mathematics and combinatorics and optimization.