[Merged by Bors] - feat(Algebra/ModuleCat): extension of scalars is comonadic for a faithfully flat algebra#32326
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PR summary 0bc483ae44
|
| File | Base Count | Head Count | Change |
|---|---|---|---|
| Mathlib.RingTheory.Flat.CategoryTheory | 1596 | 1616 | +20 (+1.25%) |
Import changes for all files
| Files | Import difference |
|---|---|
Mathlib.RingTheory.Flat.CategoryTheory |
20 |
Mathlib.Algebra.Category.ModuleCat.Descent (new file) |
2019 |
Declarations diff
+ ModuleCat.preservesFiniteLimits_extendScalars_of_flat
+ ModuleCat.preservesFiniteLimits_tensorLeft_of_ringHomFlat
+ ModuleCat.reflectsIsomorphisms_extendScalars_of_faithfullyFlat
+ comonadicExtendScalars
+ iff_preservesFiniteLimits_tensorLeft
+ instance [Module.Flat R M] : PreservesFiniteLimits <| tensorLeft M := by
+ instance {R S : Type*} [Ring R] [Ring S] (f : R →+* S) :
+ lTensor_bijective_iff_bijective
+ preservesFiniteColimits_iff_forall_exact_map_and_epi
+ preservesFiniteLimits_iff_forall_exact_map_and_mono
You can run this locally as follows
## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>
## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>The doc-module for script/declarations_diff.sh contains some details about this script.
No changes to technical debt.
You can run this locally as
./scripts/technical-debt-metrics.sh pr_summary
- The
relativevalue is the weighted sum of the differences with weight given by the inverse of the current value of the statistic. - The
absolutevalue is therelativevalue divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).
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Otherwise LGTM
Thanks!
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Benchmark results for ea73cf9 against 0bc483a are in! @riccardobrasca Small changes (1✅, 1🟥)
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Thanks! bors merge |
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…hfully flat algebra (#32326) This is also known as faithfully flat descent, but the proof that these statements indeed imply each other is much longer than this PR (see #24434). This contribution was created as part of the AIM workshop "Formalizing algebraic geometry" in June 2024. Co-authored-by: Dagur Asgeirsson <dagurtomas@gmail.com> Co-authored-by: Jack McKoen <mckoen@ualberta.ca> Co-authored-by: Joël Riou <rioujoel@gmail.com> Co-authored-by: Adam Topaz <atopaz@fastmail.com>
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…hfully flat algebra (leanprover-community#32326) This is also known as faithfully flat descent, but the proof that these statements indeed imply each other is much longer than this PR (see leanprover-community#24434). This contribution was created as part of the AIM workshop "Formalizing algebraic geometry" in June 2024. Co-authored-by: Dagur Asgeirsson <dagurtomas@gmail.com> Co-authored-by: Jack McKoen <mckoen@ualberta.ca> Co-authored-by: Joël Riou <rioujoel@gmail.com> Co-authored-by: Adam Topaz <atopaz@fastmail.com>
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This is also known as faithfully flat descent, but the proof that these statements indeed imply each other is much longer than this PR (see #24434).
Co-authored-by: Dagur Asgeirsson dagurtomas@gmail.com
Co-authored-by: Jack McKoen mckoen@ualberta.ca
Co-authored-by: Joël Riou rioujoel@gmail.com
Co-authored-by: Adam Topaz atopaz@fastmail.com
This contribution was created as part of the AIM workshop
"Formalizing algebraic geometry" in June 2024.
This PR continues the work from #14203.