Saved in:
Bibliographic Details
Main Authors: Hernández, Isabel, Martin, María Eugenia, Rodrigues, Rodrigo Lucas
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2501.18067
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929692280356864
author Hernández, Isabel
Martin, María Eugenia
Rodrigues, Rodrigo Lucas
author_facet Hernández, Isabel
Martin, María Eugenia
Rodrigues, Rodrigo Lucas
contents We describe the variety of Jordan superalgebras of dimension $4$ whose even part is a Jordan algebra of dimension $2$ over an algebraically closed field $\mathbb{F}$ of characteristic $0$. We prove that the variety has $25$ irreducible components, $24$ of them correspond to the Zariski closure of the $GL_2(\mathbb{F})\times GL_2(\mathbb{F})$-orbits of rigid superalgebras and the other one is the Zariski closure of an union of orbits of an infinite family of superalgebras, none of them being rigid. Furthermore, it is known that the question of the existence of a rigid Jordan algebra whose second cohomology group does not vanish is still an open problem. We solve this problem in the context of superalgebras, showing a four-dimensional rigid Jordan superalgebra whose second cohomology group does not vanish.
format Preprint
id arxiv_https___arxiv_org_abs_2501_18067
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle The Variety of Jordan Superalgebras of dimension four and even part of dimension two
Hernández, Isabel
Martin, María Eugenia
Rodrigues, Rodrigo Lucas
Rings and Algebras
We describe the variety of Jordan superalgebras of dimension $4$ whose even part is a Jordan algebra of dimension $2$ over an algebraically closed field $\mathbb{F}$ of characteristic $0$. We prove that the variety has $25$ irreducible components, $24$ of them correspond to the Zariski closure of the $GL_2(\mathbb{F})\times GL_2(\mathbb{F})$-orbits of rigid superalgebras and the other one is the Zariski closure of an union of orbits of an infinite family of superalgebras, none of them being rigid. Furthermore, it is known that the question of the existence of a rigid Jordan algebra whose second cohomology group does not vanish is still an open problem. We solve this problem in the context of superalgebras, showing a four-dimensional rigid Jordan superalgebra whose second cohomology group does not vanish.
title The Variety of Jordan Superalgebras of dimension four and even part of dimension two
topic Rings and Algebras
url https://arxiv.org/abs/2501.18067