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arXiv · 2305.05622

Multilinear Hyperquiver Representations

Tommi Muller·Vidit Nanda·Anna Seigal
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Abstract

We count singular vector tuples of a system of tensors assigned to the edges of a directed hypergraph. To do so, we study the generalisation of quivers to directed hypergraphs. Assigning vector spaces to the nodes of a hypergraph and multilinear maps to its hyperedges gives a hyperquiver representation. Hyperquiver representations generalise quiver representations (where all hyperedges are edges) and tensors (where there is only one multilinear map). The singular vectors of a hyperquiver representation are a compatible assignment of vectors to the nodes. We compute the dimension and degree of the variety of singular vectors of a sufficiently generic hyperquiver representation. Our formula specialises to known results that count the singular vectors and eigenvectors of a generic tensor. Lastly, we study a hypergraph generalisation of the inverse tensor eigenvalue problem and solve it algorithmically.

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Tommi Muller, Vidit Nanda, Anna Seigal. 2023-05-09. Multilinear Hyperquiver Representations. https://arxiv.org/abs/2305.05622

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