Smooth diagonal pullback of continuous multilinear maps #
Mathlib bundles multilinear pullback as the continuous multilinear operator
ContinuousMultilinearMap.compContinuousLinearMapContinuousMultilinear.
Applying the same continuous linear map in every input slot gives an operator-valued
function that is smooth at every order, including the analytic order ω.
theorem
ContinuousMultilinearMap.contDiff_compContinuousLinearMapContinuousMultilinear_diagonal
{𝕜 : Type u_1}
{E : Type u_2}
{F : Type u_3}
{G : Type u_4}
{ι : Type u_5}
[NontriviallyNormedField 𝕜]
[NormedAddCommGroup E]
[NormedSpace 𝕜 E]
[NormedAddCommGroup F]
[NormedSpace 𝕜 F]
[NormedAddCommGroup G]
[NormedSpace 𝕜 G]
[Fintype ι]
(n : WithTop ℕ∞)
:
ContDiff 𝕜 n fun (f : E →L[𝕜] F) =>
(compContinuousLinearMapContinuousMultilinear 𝕜 (fun (x : ι) => E) (fun (x : ι) => F) G) fun (x : ι) => f
Pulling back continuous multilinear maps along the same continuous linear map in every
input slot is smooth as an operator-valued function, at every order including ω.