| Title: |
The weak commutativity construction for Lie algebras |
| Authors: |
de Mendonça, Luis Augusto |
| Publication Year: |
2018 |
| Collection: |
Mathematics |
| Subject Terms: |
Mathematics - Rings and Algebras, Mathematics - Group Theory |
| More Details: |
We study the analogue of Sidki's weak commutativity construction, defined originally for groups, in the category of Lie algebras. This is the quotient $\chi(\mathfrak{g})$ of the Lie algebra freely generated by two isomorphic copies $\mathfrak{g}$ and $\mathfrak{g}^{\psi}$ of a fixed Lie algebra by the ideal generated by the brackets $[x,x^{\psi}]$, for all $x$. We exhibit an abelian ideal of $\chi(\mathfrak{g})$ whose associated quotient is a subdirect sum in $\mathfrak{g} \oplus \mathfrak{g} \oplus \mathfrak{g}$ and we give conditions for this ideal to be finite dimensional. We show that $\chi(\mathfrak{g})$ has a subquotient that is isomorphic to the Schur multiplier of $\mathfrak{g}$. We prove that $\chi(\mathfrak{g})$ is finitely presentable or of homological type $FP_2$ if and only if $\mathfrak{g}$ has the same property, but $\chi(\mathfrak{f})$ is not of type $FP_3$ if $\mathfrak{f}$ is a non-abelian free Lie algebra.
Comment: Incorporated referee's suggestions, results unchanged |
| Document Type: |
Working Paper |
| DOI: |
10.1016/j.jalgebra.2019.04.007 |
| Access URL: |
http://arxiv.org/abs/1808.10303 |
| Accession Number: |
edsarx.1808.10303 |
| Database: |
arXiv |
