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
[Merged by Bors] - feat(measure_theory/measure/hausdorff): (μH[1] : measure ℝ) = volume
#18982
Conversation
|
||
theorem hausdorff_measure_measure_preserving_fun_unique [unique ι] | ||
[topological_space.second_countable_topology X] (d : ℝ) : | ||
measure_preserving (measurable_equiv.fun_unique ι X) μH[d] μH[d] := |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Do we have this for any isometry_equiv
?
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
I think it's only true for isometry equivs which are also measurable
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Ah nevermind, my comment was stupid. Updated.
Otherwise LGTM. Thanks! |
✌️ eric-wieser can now approve this pull request. To approve and merge a pull request, simply reply with |
Co-authored-by: Yury G. Kudryashov <urkud@urkud.name>
bors merge |
#18982) And similarly for `(μH[2] : measure ℝ × ℝ) = volume`. This addresses the TODO comment in the docstring. The `hausdorff_measure_pi_real` proof has been moved to the bottom of the file so that it can be kept next to the new results.
Pull request successfully merged into master. Build succeeded! The publicly hosted instance of bors-ng is deprecated and will go away soon. If you want to self-host your own instance, instructions are here. If you want to switch to GitHub's built-in merge queue, visit their help page. |
(μH[1] : measure ℝ) = volume
(μH[1] : measure ℝ) = volume
* leanprover-community/mathlib#19025 (already changed while porting) * leanprover-community/mathlib#18982
And similarly for
(μH[2] : measure ℝ × ℝ) = volume
.This addresses the TODO comment in the docstring.
The
hausdorff_measure_pi_real
proof has been moved to the bottom of the file so that it can be kept next to the new results.