activity
20152026
most citedEncoding CSP into CCS

8 citations · 25 across the 33 of their papers we have counts for

collaborators

37 papers

math.RT2026

Universally extendible characters

Benjamin Sambale

Let theta be an ordinary character or a Brauer character of a finite group N. We show that theta extends to every overgroup if and only if Z(N) <= Ker(the…

math.CO2026

Minimal Cayley graphs with large chromatic number

James Davies, Meike Hatzel, Liana Yepremyan

Resolving Babai's minimal Cayley graph problem, we construct finite minimal Cayley graphs with arbitrarily large chromatic number.

math.CO2026

A directed flat wall theorem excluding a crossrow grid

Meike Hatzel, Ken-ichi Kawarabayashi, Stephan Kreutzer +1

The graph minor project contains the most influential results in recent undirected graph theory research. There has been progress in recent years in generalising some of their resu…

math.CO2026

An Erdős-Pósa theorem for cycles and faces of distinct lengths

J. Pascal Gollin, Maximilian Gorsky, Meike Hatzel +6

We show that for every , every graph contains vertex-disjoint cycles of different lengths, or there exists a set with $|X| \in \mathcal…

cs.DM2026

Cycles of Well-Linked Sets II: an Elementary Bound for the Directed Grid Theorem

Meike Hatzel, Stephan Kreutzer, Marcelo Garlet Milani +1

In 2015, Kawarabayashi and Kreutzer proved the Directed Grid Theorem - the generalisation of the well-known Excluded Grid Theorem to directed graphs - confirming a conjecture by Re…

math.CO2025

Unavoidable butterfly minors in digraphs of large cycle rank

Meike Hatzel, O-joung Kwon, Myounghwan Lee +1

Cycle rank is one of the depth parameters for digraphs introduced by Eggan in 1963. We show that there exists a function such that every digraph of cyc…