Mathematics – Algebraic Geometry
Scientific paper
2000-05-25
Mathematics
Algebraic Geometry
40 pages, LaTeX 2.09
Scientific paper
Let X be a smooth complex surface of general type such that the image of the canonical map $\phi$ of X is a surface $\Sigma$ and that $\phi$ has degree $\delta\geq 2$. Let $\epsilon\colon S\to \Sigma$ be a desingularization of $\Sigma$ and assume that the geometric genus of S is not zero. Beauville has proved that in this case S is of general type and $\epsilon$ is the canonical map of S. Beauville has also constructed the only infinite series of examples $\phi:X\to \Sigma$ with the above properties that was known up to now. Starting from his construction, we define a {\em good generating pair}, namely a pair $(h:V\to W, L)$ where h is a finite morphism of surfaces and L is a nef and big line bundle of W satisfying certain assumptions. We show that by applying a construction analogous to Beauville's to a good generating pair one obtains an infinite series of surfaces of general type whose canonical map is 2-to-1 onto a canonically embedded surface. In this way we are able to construct more infinite series of such surfaces. In addition, we show that good generating pairs have bounded invariants and that there exist essentially only 2 examples with $\dim |L|>1$. The key fact that we exploit for obtaining these results is that the Albanese variety P of V is a Prym variety and that the fibre of the Prym map over P has positive dimension.
Ciliberto Ciro
Pardini Rita
Tovena Francesca
No associations
LandOfFree
Prym varieties and the canonical map of surfaces of general type does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Prym varieties and the canonical map of surfaces of general type, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Prym varieties and the canonical map of surfaces of general type will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-200909