Approximating the Orthogonality Dimension of Graphs and Hypergraphs

  title={Approximating the Orthogonality Dimension of Graphs and Hypergraphs},
  author={Ishay Haviv},
  • I. Haviv
  • Published in MFCS 2019
  • Mathematics, Computer Science
A $t$-dimensional orthogonal representation of a hypergraph is an assignment of nonzero vectors in $\mathbb{R}^t$ to its vertices, such that every hyperedge contains two vertices whose vectors are orthogonal. The orthogonality dimension of a hypergraph $H$, denoted by $\overline{\xi}(H)$, is the smallest integer $t$ for which there exists a $t$-dimensional orthogonal representation of $H$. In this paper we study computational aspects of the orthogonality dimension of graphs and hypergraphs. We… Expand
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  • I. Haviv
  • Mathematics, Computer Science
  • Eur. J. Comb.
  • 2019
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