English

Biquadratic spaces of length two

Representation Theory 2024-12-31 v1 Logic

Abstract

A tensor space is a vector space equipped with a finite collection of multilinear forms. The length of a tensor space is its length as a representation of its symmetry group. Infinite dimension tensor spaces of finite length are special, highly symmetrical objects. We classify the (universal) biquadratic spaces of length two; there are seven families of them. As a corollary, we establish some cases of the linear analog of the Ryll-Nardzewski theorem. We view this work as a first attempt to classify highly symmetrical tensor spaces.

Keywords

Cite

@article{arxiv.2412.20681,
  title  = {Biquadratic spaces of length two},
  author = {Alessandro Danelon and Andrew Snowden},
  journal= {arXiv preprint arXiv:2412.20681},
  year   = {2024}
}

Comments

26 pages

R2 v1 2026-06-28T20:51:36.664Z