Zulip Chat Archive
Stream: Is there code for X?
Topic: Eval as a linear map from CLM to codomain
Moritz Doll (Mar 19 2024 at 03:12):
Does the following definition exist somewhere? I would be shocked if not, but I could not find it
variable (𝕜 E : Type*) [NormedField 𝕜] [AddCommGroup E] [Module 𝕜 E] [TopologicalSpace E]
@[simps]
def evalLM (a : E) : (E →L[𝕜] 𝕜) →ₗ[𝕜] 𝕜 where
toFun v := v a
map_add' := fun _ _ ↦ rfl
map_smul' := fun _ _ ↦ rfl
Jireh Loreaux (Mar 19 2024 at 03:34):
How does docs#ContinuousLinearMap.apply' work for you?
Jireh Loreaux (Mar 19 2024 at 03:36):
If the hypotheses of that are too strong, then I'm betting we don't have the version you want.
Moritz Doll (Mar 19 2024 at 03:36):
I don't want to assume that E
is a normed space
Jireh Loreaux (Mar 19 2024 at 03:36):
We also have docs#LinearMap.applyₗ'
Jireh Loreaux (Mar 19 2024 at 03:38):
You could compose that with a forgetful morphism.
Moritz Doll (Mar 19 2024 at 03:41):
Yes, that sounds very reasonable. The context is that I want to prove continuity of the evaluation for the pointwise convergence topology:
theorem PointwiseConvergenceCLM.eval_continuous (a : E) :
Continuous (fun (v : E →Lₛ[𝕜] 𝕜) ↦ v a) := by sorry
and the proof uses that the map is linear (to reduce everything to 0 nhds). Also I want to bundle this definition (and the corresponding one for the weak dual)
Moritz Doll (Mar 19 2024 at 03:49):
Ah crap, I think I have to define my own docs#ContinuousLinearMap.coeLM variant
Antoine Chambert-Loir (Mar 19 2024 at 10:24):
Yes, that would be nice to refactor this stuff so that they hold for arbitrary topological vector spaces.
Last updated: May 02 2025 at 03:31 UTC