Projective schemes with degenerate general hyperplane section.
Projective schemes with degenerate general hyperplane section. II.
Projectively Normal Line Bundles on K-Gonal Curves and Rational Surfaces
2000 Mathematics Subject Classification: 14H50.Here we prove the projective normality of several special line bundles on a general k-gonal curve.* The author was partially supported by MIURST and GNSAGA of INdAM (Italy) ** The author was partially supported by KOSEF # R01-2002-000-00051-0
Propriétés des diamètres des courbes géométriques
Propriétés des systèmes de coniques, dans lesquels se trouvent des conditions de perpendicularité entre diverses séries de droites
Propriétés des systèmes de coniques relatives, toutes, à certaines séries de normales en rapport avec d'autres lignes ou divers points
Quartic surfaces with 16 skew conics.
Quasi-homogeneous linear systems on ℙ² with base points of multiplicity 7, 8, 9, 10
We prove that the Segre-Gimigliano-Harbourne-Hirschowitz conjecture holds for quasi-homogeneous linear systems on ℙ² for m = 7, 8, 9, 10, i.e. systems of curves of a given degree passing through points in general position with multiplicities at least m,...,m,m₀, where m = 7, 8, 9, 10, m₀ is arbitrary.
Rational 1- and 2-cuspidal plane curves.
Rational approximation to real points on conics
A point with coordinates in a subfield of of transcendence degree one over , with linearly independent over , may have a uniform exponent of approximation by elements of that is strictly larger than the lower bound given by Dirichlet’s box principle. This appeared as a surprise, in connection to work of Davenport and Schmidt, for points of the parabola . The goal of this paper is to show that this phenomenon extends to all real conics defined over , and that the largest exponent of...
Rational Bézier curves with infinitely many integral points
In this paper we consider rational Bézier curves with control points having rational coordinates and rational weights, and we give necessary and sufficient conditions for such a curve to have infinitely many points with integer coefficients. Furthermore, we give algorithms for the construction of these curves and the computation of theirs points with integer coefficients.
Raumkurven vierter Ordnung zweiter Art auf einer Kreisringfläche.
Recherche des singularités qui ont rapport à une droite multiple d'une surface
Recherches analytiques sur la surface du troisième ordre qui est la réciproque de la surface de Steiner
Recovering an algebraic curve using its projections from different points. Applications to static and dynamic computational vision
We study some geometric configurations related to projections of an irreducible algebraic curve embedded in onto embedded projective planes. These configurations are motivated by applications to static and dynamic computational vision. More precisely, we study how an irreducible closed algebraic curve embedded in , of degree and genus , can be recovered using its projections from points onto embedded projective planes. The embeddings are unknown. The only input is the defining equation of...
Regularity bounds by minimal generators and Hilbert function.
Rokhlin's formula for dividing T-curves.
Semidefinite geometry of the numerical range.
Seshadri positive curves in a smooth projective -fold
A notion of positivity, called Seshadri ampleness, is introduced for a smooth curve in a polarized smooth projective -fold , whose motivation stems from some recent results concerning the gonality of space curves and the behaviour of stable bundles on under restriction to . This condition is stronger than the normality of the normal bundle and more general than being defined by a regular section of an ample rank- vector bundle. We then explore some of the properties of Seshadri-ample curves....
Simple constructions of algebraic curves with nodes