A remark on the counterexample to the unknotting number conjecture

2025/07/18 by Wang, Chao, Zhang, Yimu
#57K10 #FOS: Mathematics #Geometric Topology (math.GT)

paper · doi:10.48550/arxiv.2507.14265

Abstract

By using Snappy, M. Brittenham and S. Hermiller discovered a very surprising example that u(7₁#7₁)≤ 5<6=u(7₁)+u(7₁), where 7₁ is the (2,7)-torus knot and 7₁ is its mirror image. Based on their work, we give a direct verification of this fact.

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