- Commit
- 97047d350f1e0d957f975b0a0de9cb2f14e72f01
- Parent
- c40b552473720d093a2e10273aeffd40ecf4e5f6
- Author
- Pablo <pablo-escobar@riseup.net>
- Date
Changed the notation for elements of a basis
Source code for my notes on representations of semisimple Lie algebras and Olivier Mathieu's classification of simple weight modules
Changed the notation for elements of a basis
1 file changed, 20 insertions, 20 deletions
Status | File Name | N° Changes | Insertions | Deletions |
Modified | sections/mathieu.tex | 40 | 20 | 20 |
diff --git a/sections/mathieu.tex b/sections/mathieu.tex @@ -273,20 +273,20 @@ % TODO: Define what a set commuting roots is \begin{lemma}\label{thm:nice-basis-for-inversion} Let \(V\) be an irreducible infinite-dimensional admissible - \(\mathfrak{g}\)-module. There is a basis \(\Sigma = \{\alpha_1, \ldots, - \alpha_n\}\) of \(Q\) consisting a commuting roots and such that the elements - \(F_{\alpha_i}\) all act injectively on \(V\). + \(\mathfrak{g}\)-module. There is a basis \(\Sigma = \{\beta_1, \ldots, + \beta_n\}\) of \(Q\) consisting a commuting roots and such that the elements + \(F_{\beta_i}\) all act injectively on \(V\). \end{lemma} \begin{corollary} Let \(\Sigma\) be as in lemma~\ref{thm:nice-basis-for-inversion} and - \((F_\alpha : \alpha \in \Sigma) \subset \mathcal{U}(\mathfrak{g})\) be - the multiplicative subset generated by \(F_\alpha\), \(\alpha \in \Sigma\). - The \(K\)-algebra \(\mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in + \((F_\beta : \beta \in \Sigma) \subset \mathcal{U}(\mathfrak{g})\) be + the multiplicative subset generated by \(F_\beta\), \(\beta \in \Sigma\). + The \(K\)-algebra \(\mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)}\) is well defined and the localization map \begin{align*} V & - \to \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)} + \to \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)} \otimes V \\ u & \mapsto 1 \otimes u \end{align*} @@ -304,30 +304,30 @@ % restrict it via the localization map, wich is injective in this case \begin{proposition}\label{thm:nice-automorphisms-exist} There is a family of automorphisms \(\{\theta_\lambda : - \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)} \to - \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)}\}_{\lambda \in + \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)} \to + \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)}\}_{\lambda \in \mathfrak{h}^*}\) such that \begin{enumerate} - \item \(\theta_{k_1 \alpha_1 + \cdots k_n \alpha^n}(u) = - F_{\alpha_1}^{k_1} \cdots F_{\alpha_n}^{k_n} u F_{\alpha_1}^{- k_n} - \cdots F_{\alpha_n}^{- k_1}\) for all \(u \in - \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)}\) and \(k_1, + \item \(\theta_{k_1 \beta_1 + \cdots k_n \beta_n}(u) = + F_{\beta_1}^{k_1} \cdots F_{\beta_n}^{k_n} u F_{\beta_1}^{- k_n} + \cdots F_{\beta_n}^{- k_1}\) for all \(u \in + \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)}\) and \(k_1, \ldots, k_n \in \mathbb{Z}\). - \item For each \(u \in \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in + \item For each \(u \in \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)}\) the map \begin{align*} \mathfrak{h}^* & - \to \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)} \\ + \to \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)} \\ \lambda & \mapsto \theta_\lambda(u) \end{align*} is polynomial. - \item If \(W\) is the \(\mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in - \Sigma)}\)-module \(\mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in + \item If \(W\) is the \(\mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in + \Sigma)}\)-module \(\mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)} \otimes V\), \(\lambda, \mu \in \mathfrak{h}^*\) and - \(\theta_\lambda W\) is the \(\mathcal{U}(\mathfrak{g})_{(F_\alpha : - \alpha \in \Sigma)}\)-module \(W\) twisted by the automorphism + \(\theta_\lambda W\) is the \(\mathcal{U}(\mathfrak{g})_{(F_\beta : + \beta \in \Sigma)}\)-module \(W\) twisted by the automorphism \(\theta_\lambda\) then \(W_\mu = (\theta_\lambda W)_{\mu + \lambda}\). \end{enumerate} @@ -342,7 +342,7 @@ \begin{proof} Let \(\Lambda\) be a set of representatives of the \(Q\)-cosets in \(\mathfrak{h}^*\) with \(0 \in \Lambda\), \(W = - \mathcal{U}(\mathfrak{g})_{(F_\alpha : \alpha \in \Sigma)} + \mathcal{U}(\mathfrak{g})_{(F_\beta : \beta \in \Sigma)} \otimes_{\mathcal{U}(\mathfrak{g})} V\) be as in proposition~\ref{thm:irr-admissible-is-contained-in-nice-mod} and take \[