Linear-size universal point sets for planar graphs
Determine whether there exists a constant c such that, for every n, there is a point set of size c·n that is universal for all n-vertex planar graphs (i.e., supports straight-line crossing-free embeddings of every n-vertex planar graph).
References
Arguably, the most famous open problem in graph drawing, attributed to Bojan Mohar (1988), asks if there exist a constant $c$ such that, for every $n$ there exists a pointset of size $c\cdot n$ that is universal for the class of all $n$-vertex planar graphs.
— Free Sets in Planar Graphs: History and Applications
(2403.17090 - Dujmović et al., 25 Mar 2024) in Section Applications, Subsection Universal point subsets