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Thin Trees for near Minimum Cuts

Authors Nathan Klein , Neil Olver , Zi Song Yeoh

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LIPIcs.ICALP.2026.129.pdf
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Subject Classification

ACM Subject Classification
  • Theory of computation → Algorithm design techniques
  • Mathematics of computing → Graph theory
Keywords
  • Graph Theory
  • Thin Trees
  • Polygon Representation
  • Near Minimum Cuts

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Abstract

The strong thin tree conjecture states that every k-edge-connected graph G contains an O(1/k)-thin spanning tree, meaning a spanning tree which contains at most an O(1/k) fraction of the edges across each cut in G. This conjecture is still open despite significant effort; the best current result by Anari and Oveis Gharan shows the existence of an O(polylog log n/k)-thin tree. 
In this work, we demonstrate that the conjecture is true if one only requires thinness for the set of η-near minimum cuts of the graph for η = 1/40, in other words, for the set of cuts with fewer than (1+1/40)k edges. Our approach constructs such a tree in polynomial time. To show this, we utilize the structure of near minimum cuts, and in particular the polygon representation of Benczúr and Goemans, to reduce to the previously solved problem of finding a spanning tree that is O(1/k)-thin for all sets in a laminar family.

Cite As Get BibTex

Nathan Klein, Neil Olver, and Zi Song Yeoh. Thin Trees for near Minimum Cuts. In 53rd International Colloquium on Automata, Languages, and Programming (ICALP 2026). Leibniz International Proceedings in Informatics (LIPIcs), Volume 374, pp. 129:1-129:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/LIPIcs.ICALP.2026.129

Author Details

Nathan Klein
  • Boston University, MA, USA
Neil Olver
  • London School of Economics and Political Science, UK
Zi Song Yeoh
  • Boston University, MA, USA

Funding

Nathan Klein and Zi Song Yeoh were supported by the NSF CAREER grant CCF-2442250. Neil Olver was supported by the NWO Vidi grant 016.Vidi.189.087.

Acknowledgements

Initial discussions on this topic took place during the Trimester Program on Combinatorial Optimization at the Hausdorff Research Institute for Mathematics; we are grateful to the institute for its support.

References

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