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Mathlib.Algebra.Category.ModuleCat.Pseudofunctor

The pseudofunctors which send a commutative ring to its category of modules #

In this file, we construct the pseudofunctors CommRingCat.moduleCatRestrictScalarsPseudofunctor and RingCat.moduleCatRestrictScalarsPseudofunctor which sends a (commutative) ring to its category of modules: the contravariant functoriality is given by the restriction of scalars functors.

We also define a pseudofunctor CommRingCat.moduleCatExtendScalarsPseudofunctor: the covariant functoriality is given by the extension of scalars functors.

The pseudofunctor from LocallyDiscrete CommRingCatᵒᵖ to Cat which sends a commutative ring R to its category of modules. The functoriality is given by the restriction of scalars.

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Instances For
    @[simp]
    theorem CommRingCat.moduleCatRestrictScalarsPseudofunctor_mapComp {a✝ b✝ c✝ : CategoryTheory.LocallyDiscrete CommRingCatᵒᵖ} (x✝ : a✝ b✝) (x✝¹ : b✝ c✝) :
    CommRingCat.moduleCatRestrictScalarsPseudofunctor.mapComp x✝ x✝¹ = ModuleCat.restrictScalarsComp x✝¹.as.unop.hom x✝.as.unop.hom

    The pseudofunctor from LocallyDiscrete RingCatᵒᵖ to Cat which sends a ring R to its category of modules. The functoriality is given by the restriction of scalars.

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    • One or more equations did not get rendered due to their size.
    Instances For
      @[simp]
      theorem RingCat.moduleCatRestrictScalarsPseudofunctor_mapComp {a✝ b✝ c✝ : CategoryTheory.LocallyDiscrete RingCatᵒᵖ} (x✝ : a✝ b✝) (x✝¹ : b✝ c✝) :
      RingCat.moduleCatRestrictScalarsPseudofunctor.mapComp x✝ x✝¹ = ModuleCat.restrictScalarsComp x✝¹.as.unop.hom x✝.as.unop.hom

      The pseudofunctor from LocallyDiscrete CommRingCat to Cat which sends a commutative ring R to its category of modules. The functoriality is given by the extension of scalars.

      Equations
      • One or more equations did not get rendered due to their size.
      Instances For
        @[simp]
        theorem CommRingCat.moduleCatExtendScalarsPseudofunctor_mapComp {a✝ b✝ c✝ : CategoryTheory.LocallyDiscrete CommRingCat} (x✝ : a✝ b✝) (x✝¹ : b✝ c✝) :