Veech Groups and Polygonal Coverings
نویسندگان
چکیده
We discuss branch points of a ne coverings and their e ects on Veech groups. In particular, this allows us to show that even if one polygon tiles another, the respective Veech groups are not necessarily commensurable. We also show that there is no universal bound on the number of Teichm uller disks passing through the same point of Teichm uller space and having incommensurable lattice Veech groups.
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