- Commit
- 16983579c523d36da72edbc1738d313d12072e90
- Parent
- 188e843d61e84dcd1f1547b3894d5c2b3749d694
- Author
- Pablo <pablo-escobar@riseup.net>
- Date
Added a TODO item
Source code for my notes on representations of semisimple Lie algebras and Olivier Mathieu's classification of simple weight modules
Added a TODO item
2 files changed, 8 insertions, 1 deletion
Status | File Name | N° Changes | Insertions | Deletions |
Modified | sections/complete-reducibility.tex | 7 | 7 | 0 |
Modified | sections/sl2-sl3.tex | 2 | 1 | 1 |
diff --git a/sections/complete-reducibility.tex b/sections/complete-reducibility.tex @@ -687,6 +687,13 @@ establish\dots implies \(W\) is 2-dimensional. Take any non-zero \(w \in W\) outside of the image of the inclusion \(K \to W\). + % TODOOOOOOOOO: Fix this + % TODO: U(g) w doesn't need to be irreducible a priori. In fact we will show + % U(g) w = 0, so this whole argument is inconsistant + % TODO: The way to fix this is to prove that rho(g) is both nilpotent -- + % because the action of every element of g is strictly upper triangular -- and + % semisimple -- because it is a quotient of g, which is semisimple. We thus + % have rho(g) = 0, so that W is trivial Since \(\dim W = 2\), the irreducible component \(\mathcal{U}(\mathfrak{g}) \cdot w\) of \(w\) in \(W\) is either \(K w\) or \(W\) itself. But this component cannot be \(W\), since the image the inclusion \(K \to W\) is a
diff --git a/sections/sl2-sl3.tex b/sections/sl2-sl3.tex @@ -1099,7 +1099,7 @@ simpler than that. Hence the highest weight of \(V \oplus W\) is \(\lambda\) -- with highest weight vectors given by the sum of highest weight vectors of \(V\) and \(W\). - % TODO: Define the subrepresentation generated by a vector + % TODO: Define the subrepresentation generated by a vector beforehand Fix some \(v \in V_\lambda\) and \(w \in W_\lambda\) and consider the subrepresentation \(U = \mathcal{U}(\mathfrak{sl}_3(K)) \cdot v + w \subset V \oplus W\) generated by \(v + w\). Since \(v + w\) is a highest weight of \(V