On non-projective normal surfaces
نویسنده
چکیده
In this note we construct examples of non-projective normal proper algebraic surfaces and discuss the somewhat pathological behaviour of their Neron-Severi group. Our surfaces are birational to the product of a projective line and a curve of higher genus.
منابع مشابه
On the Projective Normality of Smooth Surfaces of Degree Nine
The projective normality of smooth, linearly normal surfaces of degree 9 in P is studied. All non projectively normal surfaces which are not scrolls over a curve are classified. Results on the projective normality of surface scrolls are also given.
متن کاملOn Abelian Families and Holomorphic Normal Projective Connections
1.) Pm(C), 2.) smooth abelian families, 3.) manifolds with universal covering Bm(C). Here Bm(C) denotes the ball in C , the non compact dual of Pm(C) in the sense of hermitian symmetric spaces. The second point inlcudes the flat case of an abelian manifold. Any compact Riemann surface admits a holomorphic normal projective connection, this is the famous uniformization theorem. Kobayashi and Och...
متن کاملNormal surfaces in topologically finite 3–manifolds
This paper investigates normal surface theory in topologically finite 3–manifolds with ideal triangulations. Treated are closed and non– compact normal surfaces, the projective solution space and the projective admissible solution space, as well as the leaf spaces of the transversely measured singular codimension–one foliations defined by admissible solutions. AMS Classification 57M25, 57N10
متن کاملComplete Projective Connections
The first examples of complete projective connections are uncovered: normal projective connections on surfaces whose geodesics are all closed and embedded are complete, as are normal projective connections induced from complete affine connections with slowly decaying positive Ricci curvature. Moreover, I explain the relationship between projective and affine connections.
متن کاملO ct 2 00 5 COMPLETE PROJECTIVE CONNECTIONS
The first examples of complete projective connections are uncovered: normal projective connections on surfaces whose geodesics are all closed and embedded are complete, as are normal projective connections induced from complete affine connections with slowly decaying positive Ricci curvature. Moreover, I explain the relationship between projective and affine connections.
متن کامل