Degenerations of cubic threefolds and matroids
نویسندگان
چکیده
منابع مشابه
Projective Degenerations of K Surfaces Gaussian Maps and Fano Threefolds
In this article we exhibit certain projective degenerations of smoothK surfaces of degree g in P whose Picard group is generated by the hyperplane class to a union of two rational normal scrolls and also to a union of planes As a consequence we prove that the general hyperplane section of such K surfaces has a corank one Gaussian map if g or g We also prove that the general such hyperplane sect...
متن کاملCorrado Segre and Nodal Cubic Threefolds
We discuss the work of Corrado Segre on nodal cubic hypersurfaces with emphasis on the cases of 6-nodal and 10-nodal cubics. In particular we discuss the Fano surface of lines and conic bundle structures on such threefolds. We review some of the modern research in algebraic geometry related to Segre’s work.
متن کاملCurves of Small Degree on Cubic Threefolds
In this article we consider the spaces H(X) parametrizing smooth curves of degree d and genus g on a smooth cubic threefold X ⊂ . For 1 ≤ d ≤ 5, we show that each variety H(X) is irreducible of dimension 2d.
متن کاملCubic Threefolds and Abelian Varieties of Dimension Five
Cubic threefolds have been studied in algebraic geometry since classical times. In [5], Clemens and Griffiths proved that the intermediate Jacobian JX of a smooth cubic threefold is not isomorphic as a principally polarized abelian variety to a product of Jacobians of curves, which implies the irrationality of X. They also established the Torelli theorem for cubic threefolds: the principally po...
متن کاملCubic threefolds and abelian varieties of dimension five. II
This paper extends joint work with R. Friedman to show that the closure of the locus of intermediate Jacobians of smooth cubic threefolds, in the moduli space of principally polarized abelian varieties (ppavs) of dimension five, is an irreducible component of the locus of ppavs whose theta divisor has a point of multiplicity three or more. This paper also gives a sharp bound on the multiplicity...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2005
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-04-07689-0