2014/01/09 by Alex Massarenti, Massarenti, Alex
Mathematics · #14D06 #14E08 #14M20 #14N05 #14N25 #Algebraic Geometry (math.AG) #FOS: Mathematics #Primary 14M22 #Secondary 14D23 #math.AG #msc:14D06 #msc:14D23 #msc:14E08 #msc:14M20 #msc:14M22 #msc:14N05 #msc:14N25
paper · pdf · doi:10.48550/arxiv.1401.2059
25 pages
arxiv created 2014/01/09 · arxiv updated 2014/01/10
Let X⊂ℙN be an irreducible, non-degenerate variety. The generalized variety of sums of powers VSPHX(h) of X is the closure in the Hilbert scheme Hilbh(X) of the locus parametrizing collections of points \x1,...,xh\ such that the (h-1)-plane ⟨ x1,...,xh⟩ passes trough a fixed general point p∈ℙN. When X = Vdn is a Veronese variety we recover the classical variety of sums of powers VSP(F,h) parametrizing additive decompositions of a homogeneous polynomial as powers of linear forms. In this paper we study the birational behavior of VSPHX(h). In particular we will show how some birational properties, such as rationality, unirationality and rational connectedness, of VSPHX(h) are inherited from the birational geometry of variety X itself.