Base curves of multicanonical systems on threefolds
Base Number Theorem for Abelian Varieties. An Infinitesimal Approach.
Base points of polar curves
The base points of the system of polar curves of an irreducible algebroid plane curve with general moduli are determined. As consequences a lower bound for the Tjurina number and many continuous analytic invariants of the curve are found.
Basepoint freeness for nef and big line bundles in positive characteristic.
Bases for the homology groups of the Hilbert scheme of points in the plane
Bases of homology spaces of the Hilbert scheme of points in an algebraic surface.
We find two basis of the spaces of rational homology of the Hilbert scheme of points in an algebraic surface, by exhibiting two candidates having as cardinalities the known Betti numbers of this scheme and showing that both intersect in a matrix of nonzero determinant.
Bemerkungen über den Zusammenhang der Flächen
Bertini theorems for weak normality
Berührungsbedingungen für p-l-s-Kegelschnitte
Betti numbers for the Hilbert function strata of the punctual Hilbert scheme in two variables.
Bi-extensions associated to divisors on abelian varieties and theta functions
Birational geometry of quadrics
We construct new birational maps between quadrics over a field. The maps apply to several types of quadratic forms, including Pfister neighbors, neighbors of multiples of a Pfister form, and half-neighbors. One application is to determine which quadrics over a field are ruled (that is, birational to the projective line times some variety) in a larger range of dimensions. We describe ruledness completely for quadratic forms of odd dimension at most 17, even dimension at most 10, or dimension 14....
Birational Morphisms to lP2: An Ideal-Theoretic Perspective.
Birational Properties of Moduli spaces of stable locally free rank-2 sheaves on algebraic surfaces.
Bivariant Chern classes for morphisms with nonsingular target varieties
W. Fulton and R. MacPherson posed the problem of unique existence of a bivariant Chern class-a Grothendieck transformation from the bivariant theory F of constructible functions to the bivariant homology theory H. J.-P. Brasselet proved the existence of a bivariant Chern class in the category of embeddable analytic varieties with cellular morphisms. In general however, the problem of uniqueness is still unresolved. In this paper we show that for morphisms having nonsingular target varieties there...
Bounded Picard groups
Boundedness for threefolds in P6 containing a smooth ruled surface as hyperplane section.
Let X ⊂ P6 be a smooth irreducible projective threefold, and d its degree. In this paper we prove that there exists a constant β such that for all X containing a smooth ruled surface as hyperplane section and not contained in a fourfold of degree less than or equal to 15, d ≤ β. Under some more restrictive hypothesis we prove an analogous result for threefolds containing a smooth ruled surface as hyperplane section and contained in a fourfold of degree less than or equal to 15.
Bounds for the number of connected components and the first Betti number mod two of a real algebraic surface
Bounds on the number of non-rational subfields of a function field.
Bounds on the Serre cohomology of projective varieties