feat(MeasureTheory.VectorMeasure): variation defined as a supremum is equal to variation defined using the Hahn-Jordan decomposition#26168
Open
oliver-butterley wants to merge 118 commits intoleanprover-community:masterfrom
Conversation
This reverts commit e2b20d9.
…utterley/Variation
Collaborator
|
This PR/issue depends on: |
…to yoh-tanimoto-vectormeasure-integral
…ormeasure-integral
Collaborator
|
This pull request has conflicts, please merge |
mathlib-bors bot
pushed a commit
that referenced
this pull request
Feb 10, 2026
…n for VectorMeasure (#26156) This PR adds variation for any `VectorMeasure` using a supremum definition. Currently mathlib has `TotalVariation` defined for a signed measure using the Hahn-Jordan decomposition, but this doesn't generalise. Motivation: generally this is an important concept but specifically as a step for proving RMK in the complex case which in turn is a step to prove the spectral theorem. This PR was migrated from #25442. PR divided into smaller pieces, this is just the definition without additional lemmas. PRs adding further results related to variation are: * #26160 * #26165 * #26168 (shows that for `SignedMeasures` the two definitions of variation coincide) Co-authored-by: @yoh-tanimoto Co-authored-by: Yoh Tanimoto <[email protected]> Co-authored-by: Yoh Tanimoto <[email protected]>
|
This pull request has conflicts, please merge |
rao107
pushed a commit
to rao107/mathlib4
that referenced
this pull request
Feb 18, 2026
…n for VectorMeasure (leanprover-community#26156) This PR adds variation for any `VectorMeasure` using a supremum definition. Currently mathlib has `TotalVariation` defined for a signed measure using the Hahn-Jordan decomposition, but this doesn't generalise. Motivation: generally this is an important concept but specifically as a step for proving RMK in the complex case which in turn is a step to prove the spectral theorem. This PR was migrated from leanprover-community#25442. PR divided into smaller pieces, this is just the definition without additional lemmas. PRs adding further results related to variation are: * leanprover-community#26160 * leanprover-community#26165 * leanprover-community#26168 (shows that for `SignedMeasures` the two definitions of variation coincide) Co-authored-by: @yoh-tanimoto Co-authored-by: Yoh Tanimoto <[email protected]> Co-authored-by: Yoh Tanimoto <[email protected]>
Maldooor
pushed a commit
to Maldooor/mathlib4
that referenced
this pull request
Feb 25, 2026
…n for VectorMeasure (leanprover-community#26156) This PR adds variation for any `VectorMeasure` using a supremum definition. Currently mathlib has `TotalVariation` defined for a signed measure using the Hahn-Jordan decomposition, but this doesn't generalise. Motivation: generally this is an important concept but specifically as a step for proving RMK in the complex case which in turn is a step to prove the spectral theorem. This PR was migrated from leanprover-community#25442. PR divided into smaller pieces, this is just the definition without additional lemmas. PRs adding further results related to variation are: * leanprover-community#26160 * leanprover-community#26165 * leanprover-community#26168 (shows that for `SignedMeasures` the two definitions of variation coincide) Co-authored-by: @yoh-tanimoto Co-authored-by: Yoh Tanimoto <[email protected]> Co-authored-by: Yoh Tanimoto <[email protected]>
pfaffelh
pushed a commit
to pfaffelh/mathlib4
that referenced
this pull request
Mar 2, 2026
…n for VectorMeasure (leanprover-community#26156) This PR adds variation for any `VectorMeasure` using a supremum definition. Currently mathlib has `TotalVariation` defined for a signed measure using the Hahn-Jordan decomposition, but this doesn't generalise. Motivation: generally this is an important concept but specifically as a step for proving RMK in the complex case which in turn is a step to prove the spectral theorem. This PR was migrated from leanprover-community#25442. PR divided into smaller pieces, this is just the definition without additional lemmas. PRs adding further results related to variation are: * leanprover-community#26160 * leanprover-community#26165 * leanprover-community#26168 (shows that for `SignedMeasures` the two definitions of variation coincide) Co-authored-by: @yoh-tanimoto Co-authored-by: Yoh Tanimoto <[email protected]> Co-authored-by: Yoh Tanimoto <[email protected]>
1 task
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Add
signedMeasure_totalVariation_eq: ifμis aSignedMeasurethen variation defined as a supremum is equal to variation defined using the Hahn-Jordan decomposition.Co-authored-by: @yoh-tanimoto
ℝ≥0∞VectorMeasure is equal to itself #26165