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arXiv · 1901.01796

On the identifiability of ternary forms

Elena Angelini·Luca Chiantini
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Abstract

We describe a new method to determine the minimality and identifiability of a Waring decomposition $A$ of a specific form (symmetric tensor) $T$ in three variables. Our method, which is based on the Hilbert function of $A$, can distinguish between forms in the span of the Veronese image of $A$, which in general contains both identifiable and not identifiable points, depending on the choice of coefficients in the decomposition. This makes our method applicable for all values of the length $r$ of the decomposition, from $2$ up to the generic rank, a range which was not achievable before. Though the method in principle can handle all cases of specific ternary forms, we introduce and describe it in details for forms of degree $8$.

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Elena Angelini, Luca Chiantini. 2019-01-07. On the identifiability of ternary forms. https://doi.org/10.1016/j.laa.2020.03.042

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