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arXiv · 2607.24691

A computer-assisted proof of Kuperberg's six-cylinder conjecture

Abstract

We prove that at most six pairwise non-overlapping infinite unit cylinders can simultaneously touch a unit ball. Six is achievable, so the answer to Kuperberg's question is exactly six. The proof is computer-assisted in the following sense: the statement is reduced to a finite case analysis with 2,954,984 cases, and in each case a program verifies that one of three inequalities between explicit polynomials with rational coefficients holds throughout a box. Each case is an elementary arithmetic check, and the complete list of cases is provided with the paper.

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BibTeXRIS

Ivan Matić, Rados Radoičić. 2026-07-29. A computer-assisted proof of Kuperberg's six-cylinder conjecture. https://arxiv.org/abs/2607.24691

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