Massey products and lower central series of free groups. (English) Zbl 0643.57002
The authors continue the study of relationships between Massey products, lower central series of groups and the Fox free differential calculus (cf. their previous paper on the subject [Can. J. Math. 36, 1119-1146 (1984; Zbl 0561.55015)]). In particular, under certain conditions the authors introduce and compute a “universal” Massey product of one- dimensional cohomology classes which has a nice feature of having zero indeterminacy.
Reviewer: V.Turaev