A 4₃ configuration of lines and conics in ℙ⁵
Studying the connection between the title configuration and Kummer surfaces we write explicit quadratic equations for the latter. The main results are presented in Theorems 8 and 16.
A Bogomolov property for curves modulo algebraic subgroups
Generalizing a result of Bombieri, Masser, and Zannier we show that on a curve in the algebraic torus which is not contained in any proper coset only finitely many points are close to an algebraic subgroup of codimension at least . The notion of close is defined using the Weil height. We also deduce some cardinality bounds and further finiteness statements.
A bound for the degree of smooth surfaces in not of general type
A bound of the degree of some rational surfaces in .
A bound on the Euler number for certain Calabi-Yau 3-folds.
A bound on the geometric genus of projective varieties
A Castelnuovo bound for smooth surfaces.
A character on the quasi-symmetric functions coming from multiple zeta values.
A characterization of
A Characterization of Balanced Rational Normal Surface Scrolls in Terms of Their Osculating Spaces II.
A characterization of non-hyperelliptic Jacobi varieties.
A characterization of quasi-homogeneous Gorenstein surface singularities
A chracterization of A-discriminantal hypersurfaces in terms of the logarithmic Gauss map.
A classification of toric varieties with few generators.
A classification theorem on Fano bundles
In this paper we classify rank two Fano bundles on Fano manifolds satisfying . The classification is obtained via the computation of the nef and pseudoeffective cones of the projectivization , that allows us to obtain the cohomological invariants of and . As a by-product we discuss Fano bundles associated to congruences of lines, showing that their varieties of minimal rational tangents may have several linear components.
A Construction of Surfaces with pg = 1, q = 0 and 2...(K2) ...8. Counter Examples of the Global Torelli Theorem.
A counterexample to a conjecture on linear systems on .
A counterexample to the theorem of Beppo Levi in three dimensions.
A criterion for a variety to be cone.
A criterion for algebraicity of certain analytic elliptic surfaces.