2023/05/17 by Yuya Nishimura, Nishimura, Yuya
Engineering · #57K10 (Primary) 68Q15 (Secondary) #Advanced Surface Polishing Techniques #FOS: Mathematics #Geometric Topology (math.GT) #Metal Forming Simulation Techniques #Metallurgy and Material Forming
paper · pdf · doi:10.48550/arxiv.2305.10024
openalex publication_date 2023/05/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The solid torus core recognition problem is the problem that, given a knot in the solid tours, decides whether the knot is the core of the solid torus. That problem is in NP since the thickened torus recognition problem is in NP. We give an alternate proof of that fact and prove that the problem is in co-NP. It is also proved that the Hopf link recognition problem is in NP and co-NP as a corollary of this result.