Flip Distance of Triangulations of Convex Polygons / Rotation Distance of Binary Trees is NP-complete
Summary
arXiv:2602.22874 presents a proof that computing the minimum number of flips between triangulations of convex polygons is NP-hard, which equates to NP-hardness of rotation distance between binary trees. The work situates the result within computational geometry, linking flip sequences to structures like the Associahedron and Tamari lattice, and cites related literature; it appears in cs.CG, cs.CC, cs.DM, cs.DS, and math.CO.