Left invariant derivations #
In this file we define the concept of left invariant derivation for a Lie group. The concept is analogous to the more classical concept of left invariant vector fields, and it holds that the derivation associated to a vector field is left invariant iff the field is.
Moreover we prove that LeftInvariantDerivation I G
has the structure of a Lie algebra, hence
implementing one of the possible definitions of the Lie algebra attached to a Lie group.
Left-invariant global derivations.
A global derivation is left-invariant if it is equal to its pullback along left multiplication by
an arbitrary element of G
.
- toFun : ContMDiffMap I (modelWithCornersSelf 𝕜 𝕜) G 𝕜 ⊤ → ContMDiffMap I (modelWithCornersSelf 𝕜 𝕜) G 𝕜 ⊤
- map_add' (x y : ContMDiffMap I (modelWithCornersSelf 𝕜 𝕜) G 𝕜 ⊤) : (↑↑self).toFun (x + y) = (↑↑self).toFun x + (↑↑self).toFun y
- map_smul' (m : 𝕜) (x : ContMDiffMap I (modelWithCornersSelf 𝕜 𝕜) G 𝕜 ⊤) : (↑↑self).toFun (m • x) = (RingHom.id 𝕜) m • (↑↑self).toFun x
- map_one_eq_zero' : ↑↑self 1 = 0
- leibniz' (a b : ContMDiffMap I (modelWithCornersSelf 𝕜 𝕜) G 𝕜 ⊤) : ↑↑self (a * b) = a • ↑↑self b + b • ↑↑self a
- left_invariant'' (g : G) : (hfdifferential ⋯) ((Derivation.evalAt 1) ↑self) = (Derivation.evalAt g) ↑self
Instances For
Equations
- LeftInvariantDerivation.instCoeDerivationContMDiffMapModelWithCornersSelfTopENat = { coe := LeftInvariantDerivation.toDerivation }
Equations
- LeftInvariantDerivation.instFunLikeContMDiffMapModelWithCornersSelfTopENat = { coe := fun (f : LeftInvariantDerivation I G) => ⇑↑f, coe_injective' := ⋯ }
Premature version of the lemma. Prefer using left_invariant
instead.
Equations
- LeftInvariantDerivation.instZero = { zero := { toDerivation := 0, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.instInhabited = { default := 0 }
Equations
- LeftInvariantDerivation.instAdd = { add := fun (X Y : LeftInvariantDerivation I G) => { toDerivation := ↑X + ↑Y, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.instNeg = { neg := fun (X : LeftInvariantDerivation I G) => { toDerivation := -↑X, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.instSub = { sub := fun (X Y : LeftInvariantDerivation I G) => { toDerivation := ↑X - ↑Y, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.hasNatScalar = { smul := fun (r : ℕ) (X : LeftInvariantDerivation I G) => { toDerivation := r • ↑X, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.hasIntScalar = { smul := fun (r : ℤ) (X : LeftInvariantDerivation I G) => { toDerivation := r • ↑X, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.instAddCommGroup = Function.Injective.addCommGroup DFunLike.coe ⋯ ⋯ ⋯ ⋯ ⋯ ⋯ ⋯
Equations
- LeftInvariantDerivation.instSMul = { smul := fun (r : 𝕜) (X : LeftInvariantDerivation I G) => { toDerivation := r • ↑X, left_invariant'' := ⋯ } }
The coercion to function is a monoid homomorphism.
Equations
- LeftInvariantDerivation.coeFnAddMonoidHom I G = { toFun := DFunLike.coe, map_zero' := ⋯, map_add' := ⋯ }
Instances For
Equations
- LeftInvariantDerivation.instModule = Function.Injective.module 𝕜 (LeftInvariantDerivation.coeFnAddMonoidHom I G) ⋯ ⋯
Evaluation at a point for left invariant derivation. Same thing as for generic global
derivations (Derivation.evalAt
).
Equations
- LeftInvariantDerivation.evalAt g = { toFun := fun (X : LeftInvariantDerivation I G) => (Derivation.evalAt g) ↑X, map_add' := ⋯, map_smul' := ⋯ }
Instances For
Equations
- LeftInvariantDerivation.instBracket = { bracket := fun (X Y : LeftInvariantDerivation I G) => { toDerivation := ⁅↑X, ↑Y⁆, left_invariant'' := ⋯ } }
Equations
- LeftInvariantDerivation.instLieRing = LieRing.mk ⋯ ⋯ ⋯ ⋯
Equations
- LeftInvariantDerivation.instLieAlgebra = LieAlgebra.mk ⋯