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arXiv · 1612.07900

Spaces of Sums of Powers and Real Rank Boundaries

Mateusz Michałek·Hyunsuk Moon
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Abstract

We investigate properties of Waring decompositions of real homogeneous forms. We study the moduli of real decompositions, so-called Space of Sums of Powers, naturally included in the Variety of Sums of Powers. Explicit results are obtained for quaternary quadrics, relating the algebraic boundary of ${\rm SSP}$ to various loci in the Hilbert scheme of four points in $\mathbb{P}^3$. Further, we study the locus of general real forms whose real rank coincides with the complex rank. In case of quaternary quadrics the boundary of this locus is a degree forty hypersurface $J(σ_3(v_3(\mathbb{P}^3)),τ(v_3(\mathbb{P}^3)))$.

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Mateusz Michałek, Hyunsuk Moon. 2016-12-23. Spaces of Sums of Powers and Real Rank Boundaries. https://arxiv.org/abs/1612.07900

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