Milnor invariants via unipotent Magnus embeddings (Q2293006)

Milnor's isotopy invarants of links, which date back to the 1950s, are notoriously difficult to compute. (His first paper on this topic was reviewed for Zbl by Reidemeister.) These authors discuss those difficulties and resolve them to a certain extent. They also refine the original Milnor invariants of higher degree, proving that their results are rationally non-trivial ``and can distinguish some links''. Compare \textit{N. Kobayashi} et al. [Topology Appl. 224, 60--72 (2017; Zbl 1420.57023)], which considered Milnor invariants of certain covering links and also showed that they ``can distinguish some links for which the ordinary Milnor invariants coincide''.