Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

feat(analysis/conformal/inner_product_space): the inversion map of a normed space and its conformality #9626

Open
wants to merge 1 commit into
base: master
Choose a base branch
from

Conversation

justadzr
Copy link
Collaborator

@justadzr justadzr commented Oct 8, 2021

I am not sure in what context the inversion map should be. I've only read about the maps as x-> x/|x|^2 due to my poor mathematical background. Thanks in advance for any suggestions/guidance.


Open in Gitpod

@justadzr justadzr added awaiting-review The author would like community review of the PR RFC Request for comment labels Oct 8, 2021

lemma fderiv_inversion {X : Type*} [inner_product_space ℝ X]
{r : ℝ} (hr : 0 < r) {x₀ : X} {y x : X} (hx : x ≠ x₀) :
fderiv ℝ (inversion hr x₀) x y = r • (∥x - x₀∥ ^ 4)⁻¹ •
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please make a has_fderiv_at version, and deduce the fderiv version from it!

@hrmacbeth hrmacbeth added awaiting-author A reviewer has asked the author a question or requested changes and removed awaiting-review The author would like community review of the PR labels Oct 9, 2021
@semorrison semorrison added the too-late This PR was ready too late for inclusion in mathlib3 label Jul 16, 2023
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
awaiting-author A reviewer has asked the author a question or requested changes RFC Request for comment too-late This PR was ready too late for inclusion in mathlib3
Projects
None yet
Development

Successfully merging this pull request may close these issues.

None yet

3 participants