2015 Barbados Graph Theory Workshop

Held March 27 - April 3, 2015 at the Bellairs Research Institute of McGill University, in Holetown, Barbados.

For more information, contact the organizers, Bruce Reed and Paul Seymour.


Marthe Bonamy, Université Montpellier 2
Pierre Charbit, Université Paris 7
Maria Chudnovsky, Princeton University
Julia Chuzhoy, Toyota Technological Institute at Chicago
Matt Devos, Simon Fraser University
Vida Dujmovic, University of Ottawa
Zdenek Dvorak, Charles University
Katherine Edwards, Princeton University
Greg Gauthier, Princeton University
Frederic Havet, CNRS
Chinh Hoang, Wilfred Laurier University
Peter Keevash, University of Oxford
Terka Klimosova, University of Warwick
Aurélie Lagoutte, Ecole Normale Supérieure de Lyon
Zhentao Li, Ecole Normale Supérieure de Paris
Chun-Hung Liu, Princeton University
Irene Lo, Columbia University
Colin McDiarmid, University of Oxford
Natasha Morrison, University of Oxford
Jon Noel, University of Oxford
Sergey Norin, McGill University
Sang-Il Oum, KAIST (Daejeon)
Guillem Perarnau, McGill University
Luke Postle, University of Waterloo
Bruce Reed, McGill University
Alex Scott, University of Oxford
Paul Seymour, Princeton University
Anastasios Sidiropoulos, Ohio State University
Sophie Spirkl, Princeton University
Maya Stein, Universidad de Chile
Stéphan Thomassé, Ecole Normale Supérieure de Lyon
Liana Yepremyan, McGill University
Lena Yuditsky, McGill University


Saturday (March 28) morning

Presentation of open problems; here is a pdf file of the problems presented, and notes on what we proved about them during the week of the workshop.

Saturday afternoon

  1. Matt Devos: ``A new proof of the 6-flow theorem''
  2. Progress report (Paul Seymour)

Sunday morning

Julia Chuzhoy: ``Polynomial bounds for the grid minor theorem, Part I''

Sunday afternoon

  1. Stéphan Thomassé: ``Partitioning the edges of a graph into paths of fixed length''
  2. Progress reports (Katie Edwards, Julia Chuzhoy, Alex Scott)

Monday morning

  1. Julia Chuzhoy: ``Polynomial bounds for the grid minor theorem, Part II''
  2. Guillam Perarnau: ``Bridge-addable classes''

Monday afternoon

  1. Sang-Il Oum: ``A version of Hadwiger's conjecture''
  2. Chun-Hung Liu: ``Colouring so that monochromatic components have bounded size''

Tuesday morning

  1. Bruce Reed: ``Iterative compression''
  2. Progress report (Maria Chudnovsky)

Tuesday afternoon

  1. Luke Postle: ``Colouring and MAD''
  2. Alex Scott: ``Holes in triangle-free graphs with large chromatic number''

Wednesday morning

  1. Frederic Havet: ``Subdigraphs of digraphs with large chromatic number''
  2. Pierre Charbit: ``Induced subdigraphs of digraphs with large chromatic number''
  3. Progress reports (Sergey Norin, Zdenek Dvorak)

Wednesday afternoon

Free afternoon

Thursday morning

  1. Maria Chudnovsky: ``Colouring C(4)-free perfect graphs''
  2. Peter Keevash: ``Triangle decompositions''
  3. Maya Stein: ``Covering with monochromatic paths''

Thursday afternoon

  1. Zdenek Dvorak: ``Precolouring extension in triangle-free planar graphs''
  2. Progress reports (Colin McDiarmid, Katie Edwards)
Here are Julia Chuzhoy's photos of the meeting.