Unknotting is in AM ∩ co-AM

  • Authors:
  • Masao Hara;Seiichi Tani;Makoto Yamamoto

  • Affiliations:
  • Tokai University, Haratsuka-shi, Japan;Nihon University, Setagaya-ku, Tokyo, Japan;Chuo University, Bunkyo-ku, Tokyo, Japan

  • Venue:
  • SODA '05 Proceedings of the sixteenth annual ACM-SIAM symposium on Discrete algorithms
  • Year:
  • 2005

Quantified Score

Hi-index 0.00

Visualization

Abstract

Hass, Lagarias, and Pippenger analyzed the computational complexity of various decision problems in knot theory. They proved that the problem whether a given knot is unknotting is in NP, and conjectured that the problem is contained in NP∩co-NP. Agol, Hass, and Thurston proved that the problem called ManifoldGenus, which is a general problem of Unknotting, is NP-complete. We construct an interactive proof system for Knotting, and prove that the problem is contained in IP(2). Consequently, Unknotting is contained in AM ∩ co-AM. If Unknotting is NP-complete, then Σ2p = Π2p.