OAI/GroupTheory/PolycyclicRecognition/Geometry/ComplexAdjointWeights.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Complex adjoint weights for solvable real Lie algebras

The existing simultaneous-basis construction applies over the complex numbers as well. Its restriction to real vectors supplies the weights whose lifted group characters are used in the general solvable lattice argument.

  1. def OAI.PolycyclicRecognition.complexificationLieHom line 26

    Source documentation

    The canonical real Lie homomorphism into the complexification.

    def complexificationLieHom : L →ₗ⁅ℝ⁆ ℂ ⊗[ℝ] L :=
    …
  2. theorem OAI.PolycyclicRecognition.complexificationLieHom_injective line 33
  3. theorem OAI.PolycyclicRecognition.exists_complex_triangular_adjoint_basis line 41

    Source documentation

    A complex triangular basis of the actual complexified adjoint action.

    theorem exists_complex_triangular_adjoint_basis [FiniteDimensional ℝ L]
        [LieAlgebra.IsSolvable L] :
        ∃ (n : ℕ) (b : Basis (Fin n) ℂ (ℂ ⊗[ℝ] L)),
          ∀ x : ℂ ⊗[ℝ] L,
            (LinearMap.toMatrix b b (LieAlgebra.ad ℂ (ℂ ⊗[ℝ] L) x)).IsUpperTriangular := by
    …
  4. def OAI.PolycyclicRecognition.complexifiedAdjointMatrix line 49

    Source documentation

    The complexified adjoint matrices, restricted to the original real algebra.

    def complexifiedAdjointMatrix {n : ℕ} (b : Basis (Fin n) ℂ (ℂ ⊗[ℝ] L)) :
        L →ₗ⁅ℝ⁆ Matrix (Fin n) (Fin n) ℂ := by
    …
  5. theorem OAI.PolycyclicRecognition.complexifiedAdjointMatrix_apply line 58