Jonathan Rollin
 Friday, 15:3016:30
 Kollegiengebäude Mathematik (20.30)
 1.039
 +49721 608 43784
 jonathan.rollin@kit.edu

Karlsruher Institut für Technologie
Fakultät für Mathematik
Institut für Algebra und Geometrie
Kaiserstr. 8993  76133 Karlsruhe
Since April 2018 I am PostDoc with André Schulz at the University of Hagen.
I was a member of the research group on discrete mathematics since October 2013. In May 2017 I finished my PhD here and stayed in the group until March 2018. Before starting the PhD I studied computer sciences and mathematics here in Karlsruhe, where my main focus was already on graph theory and combinatorics.
I am interested in many areas of graph theory and combinatorics. Currently, I study different kinds of graph colorings and decompositions from an extremal point of view, which in particular includes graph Ramsey theory.
Latest research of mine focuses on ordered graphs, that is, graphs equipped with a linear ordering of the vertex set. I study how classical results from graph theory behave in the ordered setting.
Semester  Titel  Typ 

Winter Semester 2017/18  Advanced Mathematics I  Lecture 
Winter Semester 2016/17  Combinatorics in the plane  Lecture 
Winter Semester 2015/16  Advanced Mathematics I (Lecture)  Lecture 
Research Interests
Graph Colorings:
 chromatic number of (ordered) graphs under local constraints, conflictfree colorings, (1,r1)colorings
Ramsey Theory:
 Ramsey equivalence, Ramsey multiplicity, ordered graph Ramsey theory
Graph Decompositions:
 induced arboricity, {a,b}factors
Publications
 Tanja Hartmann, Jonathan Rollin, Ignaz Rutter, "Regular augmentation of planar graphs" {url} Algorithmica, 73(2): 1–65, 2015
 Maria Axenovich, Jonathan Rollin, "Brooks type results for conflictfree colorings and {a, b}factors in graphs" {file} Discrete Mathematics, 338(12): 2295–2301, 2015 (corrected statement of Theorem 7)
 Daniel Hoske, Jonathan Rollin, Torsten Ueckerdt, Stefan Walzer, "Playing weighted Tron on trees" {url} Discrete Mathematics, 338(12): 2341–2347, 2015
 Maria Axenovich, Jonathan Rollin, Torsten Ueckerdt, "Conditions on Ramsey nonequivalence" {url} Journal of Graph Theory, 86(2): 159–192, 2017
 Maria Axenovich, Jonathan Rollin, Torsten Ueckerdt, "Chromatic number of ordered graphs with forbidden ordered subgraphs" {url}] Accepted to Combinatorica
 Anton Bernshteyn, Omid Khormali, Ryan R. Martin, Jonathan Rollin, Danny Rorabaugh, Songling Shan, Andrew J. Uzzell, "Regular colorings and factors of regular graphs" {url} submitted
 Maria Axenovich, Daniel Goncalves, Jonathan Rollin, Torsten Ueckerdt, "The kstrong induced arboricity of a graph" {url} European Journal of Combinatorics, 67: 1–20, 2018
 Maria Axenovich, Jonathan Rollin, Torsten Ueckerdt, "The chromatic number of ordered graphs with constrained conflict graphs" {url} Australasian Journal of Combinatorics, 69: 74–104, 2017
 Jonathan Rollin, "Minimal Ordered Ramsey Graphs" {url} submitted
Dissertation
 Jonathan Rollin, "Extremal and Ramsey Type Questions for Graphs and Ordered Graphs" (2017)
Conference Talks
35'th Kolloquium über Kombinatorik, Paderborn, November, 4  5 2016
"Chromatic number of ordered graphs without forbidden ordered subgraphs"
6'th Polish Combinatorial Conference, Bedlewo, September 19  23, 2016
"Chromatic number of ordered graphs without forbidden ordered subgraphs"
Utrecht Combinatorics Workshop, Utrecht, November 7, 2014
"Brooks Type Results for ConflictFree Colorings and {a,b}factors in graphs"
Workshops
Oberwolfach Seminar “Positional Games”, May 19  25, 2013
Rocky MountainGreat Plains Graduate Research Workshop in Combinatorics, Ames IA, June 1 13, 2015