Geometry of pseudocharacters

@article{Manning2005GeometryOP,
  title={Geometry of pseudocharacters},
  author={Jason Fox Manning},
  journal={Geometry \& Topology},
  year={2005},
  volume={9},
  pages={1147-1185}
}
  • J. Manning
  • Published 30 March 2003
  • Mathematics
  • Geometry & Topology
If G is a group, a pseudocharacter f : G → R is a function which is “almost” a homomorphism. If G admits a nontrivial pseudocharacter f, we define the space of ends of G relative to f and show that if the space of ends is complicated enough, then G contains a nonabelian free group. We also construct a quasiaction by G on a tree whose space of ends contains the space of ends of G relative to f. This construction gives rise to examples of “exotic” quasi-actions on trees. 

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