English

Toward Jordan Decompositions of Tensors

Algebraic Geometry 2025-10-17 v3

Abstract

We expand on an idea of Vinberg to take a tensor space and the natural Lie algebra that acts on it and embed their direct sum into an auxiliary algebra. Viewed as endomorphisms of this algebra, we associate adjoint operators to tensors. We show that the group actions on the tensor space and on the adjoint operators are consistent, which means that the invariants of the adjoint operator of a tensor, such as the Jordan decomposition, are invariants of the tensor. We show that there is an essentially unique algebra structure that preserves the tensor structure and has a meaningful Jordan decomposition. We utilize aspects of these adjoint operators to study orbit separation and classification in examples relevant to tensor decomposition and quantum information.

Keywords

Cite

@article{arxiv.2206.13662,
  title  = {Toward Jordan Decompositions of Tensors},
  author = {Frederic Holweck and Luke Oeding},
  journal= {arXiv preprint arXiv:2206.13662},
  year   = {2025}
}

Comments

Title changed to reflect the revision. Extensive computations that will not appear in the published version are added to the appendix