Codimension one decompositions and Chow varieties

E. Carlini

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arXiv · math/0410602

Codimension one decompositions and Chow varieties

E. Carlini

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Abstract

A presentation of a degree $d$ form in $n+1$ variables as the sum of homogenous elements ``essentially'' involving $n$ variables is called a {\em codimension one decomposition}. Codimension one decompositions are introduced and the related Waring Problem is stated and solved. Natural schemes describing the codimension one decompositions of a generic form are defined. Dimension and degree formulae for these schemes are derived when the number of summands is the minimal one; in the zero dimensional case the scheme is showed to be reduced. These results are obtained by studying the Chow variety $Δ_{n,s}$ of zero dimensional degree $s$ cycles in $\PP^n$. In particular, an explicit formula for $\degΔ_{n,s}$ is determined.

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BibTeX RIS

E. Carlini. 2004-10-28. Codimension one decompositions and Chow varieties. https://arxiv.org/abs/math/0410602

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