Local moves for links with common sublinks

Abstract

A Ck-move is a local move that involves k+1 strands of a link. A Ck-move is called a Ckd-move if these k+1 strands belong to mutually distinct components of a link. Since a Ckd-move preserves all k-component sublinks of a link, we consider the converse implication: are two links with common k-component sublinks related by a sequence of Ckd-moves? We show that the answer is yes under certain assumptions, and provide explicit counter-examples for more general situations. In particular, we consider (n,k)-Brunnian links, i.e. n-component links whose k-component sublinks are all trivial. We show that such links can be deformed into a trivial link by Ckd-moves, thus generalizing a result of Habiro and Miyazawa–Yasuhara, and deduce some results on finite type invariants of (n,k)-Brunnian links.