[Merged by Bors] - feat(Analysis/InnerProductSpace/Dual, Analysis/Normed/Group/SeparationQuotient): add null subspaces#16707
Conversation
PR summary 6d539fd27fImport changes for modified filesNo significant changes to the import graph Import changes for all files
|
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
InnerProductSpace.Core by the null spaceInnerProductSpace by the null space
…ddCommGroup` (#17007) replace the assumption `NormedAddCommGroup` to `SemiNormedAddCommGroup` in various places. motivation: with the weakened assumption the results apply to `InnerProductSpace` without `definite` assumption. This is suggested in #16707, and continues from #14024. Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
j-loreaux
left a comment
There was a problem hiding this comment.
I suspect that this is not the way to proceed here. Instead, I recommend using SeparationQuotient.
If we don't already have it, you could show that if X is a Seminormed* then SeparationQuotient X is a Normed*. Then you could define the inner product space isntance on SeparationQuotient X.
The problem with putting this InnerProductSpace instance on E / nullSpace \bbk E is that we could end up with non-defeq instances later down the line. Moreover, SeparationQuotient does almost exactly what you want already, it just doesn't have the necessary instances yet.
…roductspace-quotient
sync to master
|
@j-loreaux If I use |
|
Yes, it is certainly different, and you'll need to define the norm again, assuming the instance doesn't already exist. But I think this is the cleaner approach. |
…roductspace-quotient
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
eric-wieser
left a comment
There was a problem hiding this comment.
bors d+
(again)
Thanks! Just a file rename to go.
There was a problem hiding this comment.
Now that this file doesn't mention SeparationQuotient.lean, perhaps it should be called NullSubmodule.lean or NullSpace.lean?
|
✌️ yoh-tanimoto can now approve this pull request. To approve and merge a pull request, simply reply with |
Co-authored-by: Eric Wieser <wieser.eric@gmail.com>
…roductspace-quotient
|
bors r+ |
…nQuotient): add null subspaces (#16707) Define the null submodule in an `InnerProductSpace` and the null subgroup in a `NormedAddCommGroup` and prove basic properties. ~~Define the null space in an `InnerProductSpace` without `definite` and add `InnerProduceSpace` structure to the quotient by the null space.~~ Motivation: This PR has evolved from a PR defining the `SeparationQuotient` for `InnerProductSpace`. That has been done in #17452 and now contains some other things. Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Yoh Tanimoto <57562556+yoh-tanimoto@users.noreply.github.com>
|
Pull request successfully merged into master. Build succeeded: |
…nQuotient): add null subspaces (#16707) Define the null submodule in an `InnerProductSpace` and the null subgroup in a `NormedAddCommGroup` and prove basic properties. ~~Define the null space in an `InnerProductSpace` without `definite` and add `InnerProduceSpace` structure to the quotient by the null space.~~ Motivation: This PR has evolved from a PR defining the `SeparationQuotient` for `InnerProductSpace`. That has been done in #17452 and now contains some other things. Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Yoh Tanimoto <57562556+yoh-tanimoto@users.noreply.github.com>
Define the null submodule in an
InnerProductSpaceand the null subgroup in aNormedAddCommGroupand prove basic properties.Define the null space in anInnerProductSpacewithoutdefiniteand addInnerProduceSpacestructure to the quotient by the null space.Motivation: This PR has evolved from a PR defining the
SeparationQuotientforInnerProductSpace. That has been done in #17452 and now contains some other things.SeminormedAddCommGroup#17007Normedinstances for SeparationQuotient #17452