publication . Preprint . Article . 2013

Filtrations of free groups as intersections

Ido Efrat;
Open Access English
  • Published: 06 Dec 2013
For several natural filtrations of a free group S, we express the n-th term of the filtration as the intersection of all kernels of homomorphisms from S to certain groups of upper-triangular unipotent matrices. This generalizes a classical result of Grun for the lower central filtration. In particular, we do this for the n-th term in the lower p-central filtration of S.
Persistent Identifiers
arXiv: Mathematics::Algebraic GeometryMathematics::K-Theory and Homology
free text keywords: Mathematics - Group Theory, Primary 20E05 Secondary 20E18, General Mathematics, Free group, Algebra, Homomorphism, Unipotent, Matrix (mathematics), Pure mathematics, Filtration, law.invention, law, Mathematics
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