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arXiv · 2609.38061

Kruskal-style algorithm for Boltzmann equation molecule reduction

Yvain Bruned·Valentin Clarisse
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Abstract

We are interested in the molecule reduction algorithm used by Deng, Hani and Ma. This algorithm allows them to establish a rigidity theorem, which plays a central role in the long-time derivation of the Boltzmann equation using the hard-sphere dynamics. In the present article, we show that this algorithm is a graph traversal algorithm of Kruskal type, and we prove that it constructs a Kruskal spanning tree of the input molecule.

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Yvain Bruned, Valentin Clarisse. 2026-09-29. Kruskal-style algorithm for Boltzmann equation molecule reduction. https://arxiv.org/abs/2609.38061

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