22
votes
0answers
335 views
The BCH series in terms of Lyndon words
Recently I did some explicit computations that involved the BCH series, $\log(e^x e^y)$. Here $x$ and $y$ are non-commuting variables, and the BCH series lives in the graded comple …
3
votes
1answer
161 views
About the term “tangential derivation” on a free Lie algebra.
Let $\mathcal{lie}_n$ be the free Lie algebra generated by $n$ elements $x_1,\ldots, x_n$. A derivation $u\in \text{Der}(\mathcal{lie}_n)$ is called tangential if there exist $a_i\ …
4
votes
1answer
281 views
list of Hall basis
Anyone know a place where the standard Hall basis is listed up to at lest
5 fold brackets?
and for gradedLie algebras?
The rules are clear but I'd rather not turn the crank myself …
1
vote
2answers
180 views
Invariant space of lifted Chevalley automorphisms of the tensor algebra
Question. Let $k$ be a field of characteristic $0$. Let $L$ be a $k$-vector space. Consider the subspace $S$ of $L\otimes L\otimes L\otimes L$ spanned by all tensors of the form
$ …

