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Stabilizers for nondegenerate matrices of boundary format and Steiner bundles

Carla Dionisi
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Abstract

In this paper nondegenerate multidimensional matrices of boundary format in $V_0 \otimes ... \otimes V_p$ are investigated by their link with Steiner vector bundles on product of projective spaces. For any nondegenerate matrix $A$ the stabilizer for the $SL(V_0)\times ... \times SL(V_p)$-action, $Stab(A)$, is completely described. In particular we prove that there exists an explicit action of SL(2) on $V_0 \otimes ... \otimes V_p$ such that $Stab(A)^0\subseteq SL(2)$ and the equality holds if and only if $A$ belongs to a unique $SL(V_0)\times >... \times SL(V_p)$-orbit containing the identity matrices.

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Carla Dionisi. 2003-12-16. Stabilizers for nondegenerate matrices of boundary format and Steiner bundles. https://arxiv.org/abs/math/0312264

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