- Commit
- df1d4f6972e0041bfb767c73264f052d06ece0a5
- Parent
- 08ae3830561549c71f98cebb4732a52f68aae30f
- Author
- Pablo <pablo-escobar@riseup.net>
- Date
Revised the comments on regular and integral sl(n)-sequences
Source code for my notes on representations of semisimple Lie algebras and Olivier Mathieu's classification of simple weight modules
Revised the comments on regular and integral sl(n)-sequences
1 file changed, 10 insertions, 11 deletions
Status | File Name | N° Changes | Insertions | Deletions |
Modified | sections/coherent-families.tex | 21 | 10 | 11 |
diff --git a/sections/coherent-families.tex b/sections/coherent-families.tex @@ -256,17 +256,16 @@ It should then be obvious that\dots m_n \ \text{is \emph{not} a positive integer}\}\). \end{definition} -\begin{definition} - A \(\mathfrak{sl}_n\)-sequence \(m\) is called \emph{integral} if \(m_i - m_j - \in \mathbb{Z}\) for all \(i\) and \(j\). -\end{definition} - -% TODOO: Discuss the notion of a regular weight beforehand -\begin{definition} - A \(\mathfrak{sl}_n\)-sequence \(m\) is called \emph{regular} if \(m_i \ne - m_j\) for all \(i \ne j\). A sequence is called \emph{singular} if it is not - regular. -\end{definition} +A weight \(\lambda \in \mathfrak{h}^*\) is called \emph{regular} if \((\lambda ++ \rho)(H_\alpha) \ne 0\) for all \(\alpha \in \Delta\). In terms of +\(\mathfrak{sl}_n\)-sequences, \(\lambda\) is regular if, and only if +\(m(\lambda)_i \ne m(\lambda)_j\) for all \(i \ne j\). It thus makes sence to +call a \(\mathfrak{sl}_n\)-sequence regular or singular if \(m_i \ne m_j\) for +all \(i \ne j\) or \(m_i = m_j\) for some \(i \ne j\), respectively. Similarly, +\(\lambda\) is integral if, and only if \(m(\lambda)_i - m(\lambda)_j \in +\mathbb{Z}\) for all \(i\) and \(j\), so it makes sence to call a +\(\mathfrak{sl}_n\)-sequence \(m\) integral if \(m_i - m_j \in \mathbb{Z}\) for +all \(i\) and \(j\). % TODO: Add notes on what are the sets W ⋅m ∩ 𝓟 : the connected component of % a given element is contained in its orbit, but a given orbit may contain