On the structure of fundamental groups of conic-line arrangements having a cycle in their graph

Michael Friedman, David Garber

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

The fundamental group of the complement of a plane curve is a very important topological invariant. In particular, it is interesting to find out whether this group is determined by the combinatorics of the curve or not, and whether it is a direct sum of free groups and a free abelian group, or it has a conjugation-free geometric presentation. In this paper, we investigate the structure of this fundamental group when the graph of the conic-line arrangement is a unique cycle of length n and the conic passes through all the multiple points of the cycle. We show that if n is odd, then the affine fundamental group is abelian but not conjugation-free. For the even case, if n > 4, then using quotients of the lower central series, we show that the fundamental group is not a direct sum of a free abelian group and free groups.

Original languageEnglish
Pages (from-to)34-58
Number of pages25
JournalTopology and its Applications
Volume177
DOIs
StatePublished - 1 Nov 2014
Externally publishedYes

Keywords

  • Braid monodromy
  • Conic-line arrangement
  • Conjugation-free presentation
  • Fundamental group
  • Lower central series

Fingerprint

Dive into the research topics of 'On the structure of fundamental groups of conic-line arrangements having a cycle in their graph'. Together they form a unique fingerprint.

Cite this