English

Sextonions, Zorn Matrices, and $\mathbf{e_{7 \frac12}}$

Rings and Algebras 2017-05-23 v3 High Energy Physics - Theory Representation Theory

Abstract

By exploiting suitably constrained Zorn matrices, we present a new construction of the algebra of sextonions (over the algebraically closed field C\mathbb{C}). This allows for an explicit construction, in terms of Jordan pairs, of the non-semisimple Lie algebra e712\mathbf{e_{7 \frac12}}, intermediate between e7\mathbf{e_{7}} and e8\mathbf{e_{8}}, as well as of all Lie algebras occurring in the sextonionic row and column of the extended Freudenthal Magic Square.

Keywords

Cite

@article{arxiv.1506.04604,
  title  = {Sextonions, Zorn Matrices, and $\mathbf{e_{7 \frac12}}$},
  author = {Alessio Marrani and Piero Truini},
  journal= {arXiv preprint arXiv:1506.04604},
  year   = {2017}
}

Comments

version 2 : minor refinements, Eq. (1.2) removed, and App. A added, in which we prove that - on R - the split sextonions do not contain the divisional quaternions. 14 pages, 6 figures. version 3 : Refs. added, various refinements; matches published version on Lett. Math. Phys

R2 v1 2026-06-22T09:53:46.234Z