2010/12/03 by Jérémy Blanc · 1 citation
Mathematics · #math.AG #math.DG #msc:14E07 #msc:53D99
published as Osaka J. Math. Volume 50, Number 2 (2013), 573-590 · 14 pages
arxiv created 2010/12/03 · arxiv updated 2013/08/26
We study the group of symplectic birational transformations of the plane. It is proved that this group is generated by SL(2,ℤ), the torus and a special map of order 5, as it was conjectured by A. Usnich. Then we consider a special subgroup H, of finite type, defined over any field which admits a surjective morphism to the Thompson group of piecewise linear automorphisms of ℤ2. We prove that the presentation for this group conjectured by Usnich is correct.