摘要

One can easily show that any meromorphic function on a complex closed Riemann surface can be represented as a composition of a birational map of this surface to CP2 and a projection of the image curve from an appropriate point p is an element of CP2 to the pencil of lines through p. We introduce a natural stratification of Hurwitz spaces according to the minimal degree of a plane curve such that a given meromorphic function can be represented in the above way and calculate the dimensions of these strata. We observe that they are closely related to a family of Seven varieties studied earlier by J. Harris, Z. Ran, and I. Tyomkin.

  • 出版日期2015-9