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1. • CommentRowNumber1.
   • CommentAuthorSamuel Adrian Antz
   • CommentTimeJul 17th 2024
   • (edited Jul 17th 2024)
   • PermaLink
   Author: Samuel Adrian Antz
   Format: MarkdownItexUsed unicode subscripts for indices of [[exceptional Lie groups]] including title and links. When not linked, usual formulas are used. See discussion [here](https://nforum.ncatlab.org/discussion/18215/title-convention). Links will be re-checked after all titles have been changed. (Added redirect for "E9" at the bottom of the page.) <a href="https://ncatlab.org/nlab/revision/diff/E%E2%82%89/7">diff</a>, <a href="https://ncatlab.org/nlab/revision/E%E2%82%89/7">v7</a>, <a href="https://ncatlab.org/nlab/show/E%E2%82%89">current</a>

   Used unicode subscripts for indices of exceptional Lie groups including title and links. When not linked, usual formulas are used. See discussion here. Links will be re-checked after all titles have been changed. (Added redirect for “E9” at the bottom of the page.)

   diff, v7, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeSep 16th 2024
   • (edited Sep 16th 2024)
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded a brief note ([here](https://ncatlab.org/nlab/show/E%E2%82%89#RepresentationsOfMaximalCompactSubalgebra)) on representations of the maximal compact sub-algebra $\mathfrak{k}_{9(9)}$ of $\mathfrak{e}_{9(9)}$ together with more references, notably to the recent * Benedikt König: *$\mathfrak{k}$-structure of basic representation of affine algebras* &lbrack;[arXiv:2407.12748](https://arxiv.org/abs/2407.12748)&rbrack; (I had had numerological reason to suspect the "first" $\mathfrak{k}_{9(9)}$-irrep summand in the basic $\mathfrak{e}_{9(9)}$-rep to have dimension 256 --- and I found König's article by asking Google for what is has on 256-dim reps related to $E_9$.) <a href="https://ncatlab.org/nlab/revision/diff/E%E2%82%89/11">diff</a>, <a href="https://ncatlab.org/nlab/revision/E%E2%82%89/11">v11</a>, <a href="https://ncatlab.org/nlab/show/E%E2%82%89">current</a>

   added a brief note (here) on representations of the maximal compact sub-algebra $\mathfrak{k}_{9(9)}$ of $\mathfrak{e}_{9(9)}$

   together with more references, notably to the recent

   • Benedikt König: $\mathfrak{k}$-structure of basic representation of affine algebras [arXiv:2407.12748]

   (I had had numerological reason to suspect the “first” $\mathfrak{k}_{9(9)}$-irrep summand in the basic $\mathfrak{e}_{9(9)}$-rep to have dimension 256 — and I found König’s article by asking Google for what is has on 256-dim reps related to $E_9$.)

   diff, v11, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeNov 5th 2024
   • (edited Nov 5th 2024)
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to: * [[Hermann Nicolai]], [[Henning Samtleben]]: *On $K(E_9)$*, Q. J. Pure Appl. Math. **1** (2005) 180-204 &lbrack;[arXiv:hep-th/0407055](https://arxiv.org/abs/hep-th/0407055), [doi:10.4310/PAMQ.2005.v1.n1.a8](https://dx.doi.org/10.4310/PAMQ.2005.v1.n1.a8)&rbrack; <a href="https://ncatlab.org/nlab/revision/diff/E%E2%82%89/17">diff</a>, <a href="https://ncatlab.org/nlab/revision/E%E2%82%89/17">v17</a>, <a href="https://ncatlab.org/nlab/show/E%E2%82%89">current</a>

   added pointer to:

   • Hermann Nicolai, Henning Samtleben: On $K(E_9)$, Q. J. Pure Appl. Math. 1 (2005) 180-204 [arXiv:hep-th/0407055, doi:10.4310/PAMQ.2005.v1.n1.a8]

   diff, v17, current