Complete cubics in enumerative geometry

The Enumerative Geometry of Plane Cubics. I: Smooth Cubics

We construct a variety of complete plane cubics by a sequence of five blow-ups over P9 . This enables us to translate the problem of computing characteristic numbers for a family of plane cubics into one of computing five Segre classes, and to recover classic enumerative results of Zeuthen and Maillard.

Enumerative Geometry

Given a complex projective variety V (as defined in [1]), we wish to count the curves in V that satisfy certain prescribed conditions. Let f C denote complex projective -dimensional space. In our first example, V = f C2, the complex projective plane; in the second and third, V is a general hypersurface in f C of degree 2 − 3. Call such V a cubic twofold when  = 3 and a quintic threefold wh...

Enumerative Real Algebraic Geometry

Two well-defined classes of structured polynomial systems have been studied from this point of view—sparse systems, where the structure is encoded by the monomials in the polynomials fi—and geometric systems, where the structure comes from geometry. This second class consists of polynomial formulations of enumerative geometric problems, and in this case Question 1.1 is the motivating question o...

Enumerative Real Algebrai Geometry

Geometry and Group Structures of Some Cubics

We review the group structure of a cubic in the projective complex plane and give group theoretic formulations of some geometric properties of a cubic. Then, we apply them to pivotal isocubics, in particular to the cubics of Thomson, Darboux and Lucas. We use the group structure to identify different transformations of cubics. We also characterize equivalence of cubics in terms of the Salmon cr...