33 research outputs found
Rigidity of certain solvable actions on the sphere
An analog of the Baumslag-Solitar group BS(1,k) naturally acts on the sphere
by conformal transformations. The action is not locally rigid in higher
dimension, but exhibits a weak form of local rigidity. More precisely, any
perturbation preserves a smooth conformal structure.Comment: 21 pages, no figure
Oriented Birkhoff sections of Anosov flows
This paper gives 3 different proofs (independently obtained by the 3 authors)
of the following fact: given an Anosov flow on an oriented 3 manifold, the
existence of a positive Birkhoff section is equivalent to the fact that the
flow is -covered positively twisted.Comment: 40 pages, 6 figure