Triangulations into Groups
نویسنده
چکیده
A. If a (cusped) surface S admits an ideal triangulation T with no shears, we show an efficient algorithm to give S as a quotient of hypebolic plane H by a subgroup of PSL(2,Z). The algorithm runs in time O(n logn), where n is the number of triangles in the triangulation T . The algorithm generalizes to producing fundamental groups of general surfaces and geometric manifolds of higher dimension.
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