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Without paywall: https://www.removepaywall.com/search?url=https://www.scientificamerican.com/article/new-knot-theory-discovery-overturns-long-held-mathematical-
by baruchel 1y ago
Without paywall: https://www.removepaywall.com/search?url=https://www.scientificamerican.com/article/new-knot-theory-discovery-overturns-long-held-mathematical-assumption/ https://www.removepaywall.com/search?url=https://www.scienti...
- deleted 1y ago[deleted]
- altairprime 1y agoLinked paper: https://arxiv.org/abs/2506.24088 https://arxiv.org/abs/2506.24088 “Unknotting number is not additive under connected sum” (2025 v1) > We give the first examples of a pair of knots K1,K2 in the 3-sphere for which their unknotting numbers satisfy u(K1#K2)<u(K1)+u(K2) . This answers question 1.69(B) from Kirby's problem list, "Problems in low-dimensional topology", in the negative.