Bert Gerards email: bert@gerardsbase.nl
cell phone: +31644207040
CWI
cwi disclaimer
I work in combinatorial optimization; my main research interest is matroid theory.
I work with Jim Geelen and Geoff Whittle on the structure of minor closed classes of matroids and on Rota's Conjecture. We started this Matroid Minors Project in 1999. For an up-to-date account of our work see:
  • Solving Rota's conjecture in Notices AMS, August 2014
  • The highly connected matroids in minor-closed classes
  • Structure in minor-closed classes of matroids
  • I also work on matroids with Tony Huynh and Stefan van Zwam and, on and off over time, on optimization with Michele Conforti.
    My publications (Click on items for full text versions (if available) or go to CWI Repository)

    Solving Rota's conjecture - with J. Geelen and G. Whittle

    Stable sets and graphs with no even holes - with M. Conforti and K. Pashkovich - preprint

    The highly connected matroids in minor-closed classes - with J. Geelen and G. Whittle - to appear

    Characterizing graphic matroids by a system of linear equations - with J. Geelen

    Structure in minor-closed classes of matroids - with J. Geelen and G. Whittle - survey

    On inequivalent representations of matroids over non-prime fields - with J. Geelen and G. Whittle

    Tangles, tree-decompositions, and grids in matroids - with J. Geelen and G. Whittle

    Excluding a group-labelled graph - with J. Geelen

    On the odd-minor variant of Hadwicher's conjecture - with J. Geelen, B. Reed, P. Seymour and A. Vetta

    Packing odd circuits - with M. Conforti

    Excluding a planar graph from GF(q)-representable matroids - with J. Geelen and G. Whittle

    Mixed-integer vertex covers on bipartite graphs - with M. Conforti and G. Zambelli

    Towards a matroid-minor structure theory - with J. Geelen and G. Whittle - survey

    Towards a structure theory for matrices and matroids - with J. Geelen and G. Whittle - survey

    Packing non-zero A-paths in group-labeled graphs - with M. Chudnovski, J. Geelen, L. Goddyn, M. Lohman and P. Seymour

    Obstructions to branch-decomposition of matroids - with J. Geelen, N. Robertson and G. Whittle

    Matroid T-connectivity - with J. Geelen and G. Whittle

    On Rota's Conjecture and excluded minors containing large projective geometries - with J. Geelen and G. Whittle

    Regular matroid decomposition via signed graphs - with J. Geelen

    On the excluded minors for the matroids of branch-width k - with J. Geelen, N. Robertson and G. Whittle

    Disjoint cocircuits in matroids with large rank - with J. Geelen and G. Whittle

    Note on: N.E. Aguilera, M.S. Escalante, G.L. Nasini, "A generalization of the perfect graph theorem under the disjunctive index" - with G. Mároti and A. Schrijver

    Branch width and well-quasi-ordering in matroids and graphs - with J. Geelen and G. Whittle

    The excluded minors for GF(4)-representable matroids - with J. Geelen and A. Kapoor

    A theorem of Truemper - with M. Conforti and A. Kapoor

    Strong orientations without even directed circuits - with F.B. Shepherd

    The graphs with all subgraphs t-perfect - with F.B. Shepherd

    On Tutte's characterization of graphic matroids - a graphic proof.

    Matching - survey

    A characterization of box 1/d-integral binary clutters - with M. Laurent

    An orientation theorem for graphs

    Multicommodity flows and polyhedra - survey

    On shortest T-joins and packing T-cuts

    Compact systems for T-join and perfect matching polyhedra of graphs with bounded genus

    On matrices and cutting planes

    Graphs and polyhedra - Binary spaces and cutting planes - monograph

    A short proof of Tutte's characterization of totally unimodular matrices

    A min-max relation for stable sets in graphs with no odd-K4

    Homomorphisms of graphs into odd circuits

    Total dual integrality implies local strong unimodularity - with A. Sebö

    Polyhedral combinatorics in combinatorial optimization - with A. Kolen - survey

    Matrices with the Edmonds-Johnson property - with A. Schrijver

    Sensitivity theorems in integer linear programming - with W. Cook, A. Schrijver and É. Tardos

    Testing the odd bicycle wheel inequalities for the bipartite subgraph polytope

    Spectral localization in Banach algebras - with S. Ackermans

    Edited

    Proceedings 8th IPCO Conference - with K. Aardal

    Unpublished

    On 2-vertex connected orientations

    Odd paths and circuits in planar graphs with two odd faces

    Onion skins in oriented matroids - with W. Hochstättler