My Survey on Cameron-Liebler Classes & Low Degree Functions in Vector Spaces
Earlier this year there was a conference in Budapest, Hungary, named Sum(m)it280, to honor the cumulative 280th birthday of the Péter Frankl, Zoltán Füredi, Ervin Győri and János Pach. There the organizers asked participants for survey articles for a conference volume on extremal problems in combinatorics and geometry. Now I have worked a reasonably amount […]
The Twisted $D_{5,5}(q)$ Graph
One of the greatest discovery of in the theory of distance-regular graphs has been the twisted Grassmann graph by Edwin van Dam and Jack Koolen. Here I want to describe a small variation of their construction for the twisted $ {D_{5,5}(q)}$ graph. This post mostly to preserve my blackboard on the topic. (I tend to […]
Ramsey numbers, polar spaces, and oddtowns
I have uploaded a preprint which concludes a joint work with John Bamberg and Ferdinand Ihringer that started last year during their visit to TU Delft. In this work, we have done one of my favorite things in mathematics research: combining unrelated topics to create something new in each of them. Here is a quick […]
Love in Projective Planes, Chinese Valentine’s Day & Phonotactics
A few days ago China celebrated one of many Chinese Valentine’s days: the 20th of May. Why is this a special day in China? Chinese has around 30 to 36 phonemes which is plenty, but Chinese phonotactics dictate that you can only make around 1200 syllables out of them, for instance, see this video. English […]
Students and Robots
Last year Zhirayr Avetisyan and I created a math riddle about the games cops and robbers. It was part of an outreach event to high-school student at Ghent University. You can find it in this post here. The story was that a group of mathematicians wants to walk around the city of Ghent and have […]
Refereeing
The work of mathematicians goes through peer-review which contributes to the acceptance of the correctness of our work. Peer-reviewers are of course peers, that is other mathematicians, and most of us consider this work important. At least two of my colleagues complain about how much they have to referee and (they claim) give my name […]
Classifying Cameron-Liebler Sets/Boolean Degree 1 Functions
This week I put two new preprint on the arXiv. Both are on a similar theme, so I will discuss them together. One is with Morgan Rodgers on regular sets of lines in rank 3 polar spaces. The other one is solves a problem which I have been thinking about very regularly since November 2017: […]
Post-Doc Positions at SUSTech, Shenzhen
This is not a proper “I have jobs! Please apply!” post, but more a general service announcement. It is my understanding that I can essentially have up to two post-docs here at the Southern University of Science and Technology (SUSTech) in Shenzhen without having to worry about funding too much. Shenzhen is one of the […]