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[Merged by Bors] - feat: relative differentials as a presheaf of modules #14014
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PR summary ec03e2a468Import changesNo significant changes to the import graph
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Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
…om:leanprover-community/mathlib4 into presheaf-of-modules-relative-differentials
…nto presheaf-of-modules-relative-differentials
…nto presheaf-of-modules-relative-differentials
This PR/issue depends on:
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Thanks! |
🚀 Pull request has been placed on the maintainer queue by erdOne. |
Thanks 🎉 bors merge |
In this PR, we define the type `M.Derivation φ` of derivations with values in a presheaf of `R`-modules `M` relative to a morphism of `φ : S ⟶ F.op ⋙ R` of presheaves of commutative rings over categories `C` and `D` that are related by a functor `F : C ⥤ D`. In the particular case `F` is the identity functor, we construct the universal derivation. Co-authored-by: Joël Riou <[email protected]>
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All the lean looks fine to me but I would like to be able to understand the module docstring better :-)
with values in a presheaf of `R`-modules `M` relative to | ||
a morphism of `φ : S ⟶ F.op ⋙ R` of presheaves of commutative rings | ||
over categories `C` and `D` that are related by a functor `F : C ⥤ D`. | ||
We formalize the notion of universal derivation. |
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Trying to read this first paragraph, I found myself not knowing what S was, and actually I'm still confused mathematically. If F : C => D then F.op >>> R is a presheaf of rings on D,and I'm guessing that S is a scheme because that's what it is in the next paragraph, and now I don't know what kind of object phi is supposed to be. Please feel free to add explanations so that I understand the first paragraph :-)
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Geometrically, if `f : X ⟶ S` is a morphisms of schemes (or more generally | ||
a morphism of commutative ringed spaces), we would like to apply | ||
these definitions in the case where `F` is the pullback functors from |
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these definitions in the case where `F` is the pullback functors from | |
these definitions in the case where `F` is the pullback functor from |
rings `φ' : S' ⟶ R`, we construct a derivation | ||
`DifferentialsConstruction.derivation'` which is universal. | ||
Then, the general case (TODO) shall be obtained by observing that | ||
derivations for `S ⟶ F.op ⋙ R` identify to derivations |
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derivations for `S ⟶ F.op ⋙ R` identify to derivations | |
derivations for `S ⟶ F.op ⋙ R` identify with derivations |
Pull request successfully merged into master. Build succeeded: |
In this PR, we define the type `M.Derivation φ` of derivations with values in a presheaf of `R`-modules `M` relative to a morphism of `φ : S ⟶ F.op ⋙ R` of presheaves of commutative rings over categories `C` and `D` that are related by a functor `F : C ⥤ D`. In the particular case `F` is the identity functor, we construct the universal derivation. Co-authored-by: Joël Riou <[email protected]>
In this PR, we define the type `M.Derivation φ` of derivations with values in a presheaf of `R`-modules `M` relative to a morphism of `φ : S ⟶ F.op ⋙ R` of presheaves of commutative rings over categories `C` and `D` that are related by a functor `F : C ⥤ D`. In the particular case `F` is the identity functor, we construct the universal derivation. Co-authored-by: Joël Riou <[email protected]>
In this PR, we define the type
M.Derivation φ
of derivations with values in a presheaf ofR
-modulesM
relative toa morphism of
φ : S ⟶ F.op ⋙ R
of presheaves of commutative rings over categoriesC
andD
that are related by a functorF : C ⥤ D
. In the particular caseF
is the identity functor, we construct the universal derivation.This is a refactor of #11570