Publications

Selected Papers

  1. Embedding simply connected 2-complexes in 3-space, Memoirs of the American Mathematical Society 319 (2026), no. 1625, 82 pages; pdf
  2. Canonical decompositions of 3-connected graphs (with J. Kurkofka), Advances in Combinatorics 2025:7, 73 pages; FOCS 2023, pages 1887–1920; pdf
  3. Local 2-separators, Journal of Combinatorial Theory, Series B 156 (2022), pages 101–144; pdf
  4. A Graph Minors Approach to Temporal Sequences (with W. J. Turner), STOC 2026, pages 1388–1396; pdf
  5. Graph Theory - A Survey on the Occasion of the Abel Prize for László Lovász, Jahresbericht der Deutschen Mathematiker-Vereinigung 124(2) (2022), pages 83–108; pdf

Full list

  1. A Lean 4 Formalisation of OpenAI’s Proof of the Cycle Double Cover Conjecture (with V. Bajpai and U. Okur), Preprint; pdf
  2. Stotting in positional games (with Y. Mogge), Preprint (2026); pdf
  3. Augmenting to 4-vertex connectivity is fixed-parameter tractable (with M. S. Ramanujan), SODA 2026, pages 2015–2042; pdf
  4. Hardness of Planarity for Weak Temporal Sequences of 2-Connected Graphs (with W. J. Turner), Theoretical Computer Science 1070 (2026), article 115825; pdf
  5. How Local Separators Shape Community Structure in Large Networks (with S. Frenkel), Preprint (2025); pdf
  6. A Graph Minors Approach to Temporal Sequences (with W. J. Turner), STOC 2026, pages 1388–1396; pdf
  7. Towards a Stallings-type theorem for finite groups (with G. Kontogeorgiou, J. Kurkofka and W. J. Turner), Preprint (2024); pdf
  8. How to apply tree decomposition ideas in large networks? (with S. Frenkel), accepted at IPEC; pdf
  9. Embedding simply connected 2-complexes in 3-space, Memoirs of the American Mathematical Society 319 (2026), no. 1625, 82 pages; pdf
  10. Characterising 4-tangles through a connectivity property (with J. Kurkofka), The Electronic Journal of Combinatorics 32(3) (2025), P3.26; pdf
  11. Canonical decompositions of 3-connected graphs (with J. Kurkofka), Advances in Combinatorics 2025:7, 73 pages; FOCS 2023, pages 1887–1920; pdf
  12. Dual matroids of 2-complexes—Revisited, Bulletin of the London Mathematical Society 57(7) (2025), pages 2033–2044; pdf
  13. On Andreae's Ubiquity Conjecture, Journal of Combinatorial Theory, Series B 162 (2023), pages 68–70; pdf
  14. Entanglements (with J. Kurkofka), Journal of Combinatorial Theory, Series B 164 (2024), pages 17–28; pdf
  15. A characterisation of 3-colourable 3-dimensional triangulations (with E. Nevinson and B. Saunders), Preprint (2022); pdf
  16. Graph Theory - A Survey on the Occasion of the Abel Prize for László Lovász, Jahresbericht der Deutschen Mathematiker-Vereinigung 124(2) (2022), pages 83–108; pdf
  17. Outerspatial 2-complexes: Extending the class of outerplanar graphs to three dimensions (with T. Mihaylov), The Electronic Journal of Combinatorics 30(3) (2023), P3.20; pdf
  18. A Whitney type theorem for surfaces: characterising graphs with locally planar embeddings, Combinatorica 44(6) (2024), pages 1297–1323; pdf
  19. Characterising graphs with no subdivision of a wheel of bounded diameter, Journal of Combinatorial Theory, Series B 161 (2023), pages 21–51; pdf
  20. Local 2-separators, Journal of Combinatorial Theory, Series B 156 (2022), pages 101–144; pdf
  21. Large highly connected subgraphs in graphs with linear average degree, Preprint (2020); pdf
  22. New Constructions related to the Polynomial Sphere Recognition Problem (with L. Lichev), Discrete & Computational Geometry 67(4) (2022), pages 1097–1123; pdf
  23. Canonical trees of tree-decompositions (with M. Hamann and B. Miraftab), Journal of Combinatorial Theory, Series B 152 (2022), pages 1–26; pdf
  24. The Almost Intersection Property for Pairs of Matroids on Common Groundset (with N. Bowler, S. Ghaderi and J. Wojciechowski), The Electronic Journal of Combinatorics 27(3) (2020), P3.5; pdf
  25. Embedding simply connected 2-complexes in 3-space I, Preprint; pdf
  26. Embedding simply connected 2-complexes in 3-space II, Preprint; pdf
  27. Embedding simply connected 2-complexes in 3-space III, Preprint; pdf
  28. Embedding simply connected 2-complexes in 3-space IV, Preprint; pdf
  29. Embedding simply connected 2-complexes in 3-space V, Preprint; pdf
  30. On tree-decompositions of one-ended graphs (with F. Lehner and R. G. Möller), Mathematische Nachrichten 292(3) (2019), pages 524–539; pdf
  31. Reconstruction of infinite matroids from their 3-connected minors (with N. Bowler and L. Postle), European Journal of Combinatorics 67 (2018), pages 126–144; pdf
  32. A Liouville hyperbolic souvlaki (with B. Federici and A. Georgakopoulos), Electronic Journal of Probability 22 (2017), paper 36, 19 pages; pdf
  33. The colouring number of infinite graphs (with N. Bowler, P. Komjáth and C. Reiher), Combinatorica 39(6) (2019), pages 1225–1235; pdf
  34. A short proof that every finite graph has a tree-decomposition displaying its tangles, European Journal of Combinatorics 58 (2016), pages 61–65; pdf
  35. Canonical tree-decompositions of a graph that display its k-blocks (with P. Gollin), Journal of Combinatorial Theory, Series B 122 (2017), pages 1–20; pdf
  36. Every planar graph with the Liouville property is amenable (with A. Georgakopoulos), Random Structures & Algorithms 57(3) (2020), pages 706–729; arXiv
  37. Topological cycle matroids of infinite graphs, European Journal of Combinatorics 60 (2017), pages 135–150; pdf
  38. All graphs have tree-decompositions displaying their topological ends, Combinatorica 39(3) (2019), pages 545–596; pdf
  39. Infinite trees of matroids (with N. Bowler), Preprint (2014); pdf
  40. On the intersection conjecture for infinite trees of matroids (with N. Bowler), Journal of Combinatorial Theory, Series B 151 (2021), pages 46–82; pdf
  41. Even an infinite bureaucracy eventually makes a decision, Preprint (2014); pdf
  42. Topological infinite gammoids, and a new Menger-type theorem for infinite graphs, The Electronic Journal of Combinatorics 25(3) (2018), P3.38, 22 pages; pdf
  43. Infinite graphic matroids (with N. Bowler and R. Christian), Combinatorica 38(2) (2018), pages 305–339; pdf
  44. Edge-disjoint double rays in infinite graphs: a Halin type result (with N. Bowler and J. Pott), Journal of Combinatorial Theory, Series B 111 (2015), pages 1–16; pdf
  45. Canonical tree-decompositions of finite graphs II. Essential parts (with R. Diestel, M. Hamann and F. Hundertmark), Journal of Combinatorial Theory, Series B 118 (2016), pages 268–283; pdf
  46. Canonical tree-decompositions of finite graphs I. Existence and algorithms (with R. Diestel, M. Hamann and F. Hundertmark), Journal of Combinatorial Theory, Series B 116 (2016), pages 1–24; pdf
  47. k-Blocks: a connectivity invariant for graphs (with R. Diestel, M. Hamann and F. Hundertmark), SIAM Journal on Discrete Mathematics 28(4) (2014), pages 1876–1891; pdf
  48. The ubiquity of Psi-matroids (with N. Bowler), Preprint (2013); pdf
  49. Infinite Matroids and Determinacy of Games (with N. Bowler), Preprint (2013); pdf
  50. An excluded minors method for infinite matroids (with N. Bowler), Journal of Combinatorial Theory, Series B 128 (2018), pages 104–113; pdf
  51. Matroid intersection, base packing and base covering for infinite matroids (with N. Bowler), Combinatorica 35(2) (2015), pages 153–180; pdf
  52. Matroids with an infinite circuit-cocircuit intersection (with N. Bowler), Journal of Combinatorial Theory, Series B 107 (2014), pages 78–91; pdf
  53. On the intersection of infinite matroids (with E. Aigner-Horev and J.-O. Fröhlich), Discrete Mathematics 341(6) (2018), pages 1582–1596; pdf
  54. A characterization of the locally finite networks admitting non-constant harmonic functions of finite energy, Potential Analysis 37(3) (2012), pages 229–245; pdf
  55. Connectivity and tree structure in finite graphs (with R. Diestel, F. Hundertmark and M. Stein), Combinatorica 34(1) (2014), pages 11–46; pdf

Habilitation (2018)

  • Embedding simply connected 2-complexes in 3-space, and further results on infinite graphs and matroids; pdf

Dissertation (2015)

  • Tree-decompositions in finite and infinite graphs; pdf

Master thesis (2012)

  • A characterization of the locally finite networks admitting non-constant harmonic functions of finite energy; pdf