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TERRACINI LOCI OF CODIMENSION 1 AND A CRITERION FOR PARTIALLY SYMMETRIC TENSORS

  • Edoardo Ballico (Department of Mathematics University of Trento)
  • Received : 2021.12.09
  • Accepted : 2022.04.22
  • Published : 2023.01.31

Abstract

The Terracini t-locus of an embedded variety X ⊂ ℙr is the set of all cardinality t subsets of the smooth part of X at which a certain differential drops rank, i.e., the union of the associated double points is linearly dependent. We give an easy to check criterion to exclude some sets from the Terracini loci. This criterion applies to tensors and partially symmetric tensors. We discuss the non-existence of codimension 1 Terracini t-loci when t is the generic X-rank.

Keywords

References

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