On K-spanned embeddings of projectiv manifolds.
On secant spaces to projective curves
On the birational gonalities of smooth curves
Let C be a smooth curve of genus g. For each positive integer r the birational r-gonality sr(C) of C is the minimal integer t such that there is L ∈ Pict(C) with h0(C,L) = r + 1. Fix an integer r ≥ 3. In this paper we prove the existence of an integer gr such that for every integer g ≥ gr there is a smooth curve C of genus g with sr+1(C)/(r + 1) > sr(C)/r, i.e. in the sequence of all birational gonalities of C at least one of the slope inequalities fails
Rigid meromorphic foliations on complex surfaces
On the boundedness of the set of ample vector bundles with fixed sectional genus
On vector bundles whose general sections have all projectively equivalent zero-loci
Globally invertible differentiable or holomorphic maps
On a birational classification of bundles and reflexive sheaves on surfaces
On the graded Betti numbers for large finite subsets of curves
We prove a recent conjecture of S. Lvovski concerning the periodicity behaviour of top Betti numbers of general finite subsets with large cardinality of an irreducible curve C ⊂ ℙⁿ.
The boundedness of singular subvarieties of not of a general type and with low codimension
Sia una varietà irriducibile -dimensionale localmente Cohen-Macaulay, -Gorenstein e non di tipo generale; assumiamo , e . In questo lavoro dimostriamo che e quindi che l'insieme di tutte queste varietà è parametrizzato da un insieme finito di varietà algebriche.
The rank of the multiplication map for sections of bundles on curves
Sia una curva liscia di genere ed , fasci coerenti su . Sia l'applicazione di moltiplicazione. Qui si dimostra che ha rango massimo se e è un fibrato stabile generico su . Diamo un'interpretazione geometrica dell'eventuale non-surgettività di quando sono fibrati in rette generati da sezioni globali e . Studiamo anche il caso .
Non-special projectively normal line bundles on general k-gonal curves
Let X be a sufficiently general smooth k-gonal curve of genus g and R ∈ Pic(X) the degree k spanned line bundle. We find an optimal integer z > 0 such that the line bundle is very ample and projectively normal.
On the birational gonalities of smooth curves
Let be a smooth curve of genus . For each positive integer the birational -gonality of is the minimal integer such that there is with . Fix an integer . In this paper we prove the existence of an integer such that for every integer there is a smooth curve of genus with , i.e. in the sequence of all birational gonalities of at least one of the slope inequalities fails.
Generic Curves of Small Genus in IP3 are of Maximal Rank.
On the adjunction process over a surface in char. p II: the singular case.
On the existence of curves with maximal rank in Pn.
Some more examples of curves in P3 with stable normal bundle.
On 2-Spannedness for the adjunction mapping.
On the adjunction process over a surface in char p.
The maximal rank conjecture for non-special curves in IP3.
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