Pairwise touching cylinders: existence for eight unit cylinders
Determine whether there exists a configuration of eight infinite circular cylinders of unit radius in ℝ^3 such that every pair of cylinders touches; either construct such a configuration or prove impossibility.
References
The question for $8$ cylinders remains open but it is likely that $7$ is the optimum based on numerical calculations and dimensional considerations.
— Mathematical exploration and discovery at scale
(2511.02864 - Georgiev et al., 3 Nov 2025) in Subsection “Pairwise touching cylinders” (Section 4.26)