Documentation

Mathlib.AlgebraicGeometry.AffineSpace

Affine space #

Main definitions #

noncomputable def AlgebraicGeometry.AffineSpace (n : Type v) (S : Scheme) :

𝔸(n; S) is the affine n-space over S. Note that n is an arbitrary index type (e.g. Fin m).

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    𝔸(n; S) is the affine n-space over S.

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      @[implicit_reducible]
      noncomputable instance AlgebraicGeometry.AffineSpace.over (n : Type v) (S : Scheme) :

      The map from the affine n-space over S to the integral model Spec ℤ[n].

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        Morphisms into Spec ℤ[n] are equivalent the choice of n global sections. Use homOverEquiv instead.

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          noncomputable def AlgebraicGeometry.AffineSpace.coord {n : Type v} (S : Scheme) (i : n) :

          The standard coordinates of 𝔸(n; S).

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            noncomputable def AlgebraicGeometry.AffineSpace.homOfVector {n : Type v} {S X : Scheme} (f : X S) (v : n(X.presheaf.obj (Opposite.op ))) :

            The morphism X ⟶ 𝔸(n; S) given by a X ⟶ S and a choice of n-coordinate functions.

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              noncomputable def AlgebraicGeometry.AffineSpace.homOverEquiv {n : Type v} (S : Scheme) {X : Scheme} [X.Over S] :

              S-morphisms into Spec 𝔸(n; S) are equivalent to the choice of n global sections.

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                @[simp]

                The affine space over an affine base is isomorphic to the spectrum of the polynomial ring. Also see AffineSpace.SpecIso.

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                  The affine space over an affine base is isomorphic to the spectrum of the polynomial ring.

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                    noncomputable def AlgebraicGeometry.AffineSpace.map (n : Type v) {S T : Scheme} (f : S T) :

                    𝔸(n; S) is functorial w.r.t. S.

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                      @[simp]

                      The map between affine spaces over affine bases is isomorphic to the natural map between polynomial rings.

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                        noncomputable def AlgebraicGeometry.AffineSpace.reindex {n m : Type v} (i : mn) (S : Scheme) :

                        𝔸(n; S) is functorial w.r.t. n.

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                          @[simp]
                          theorem AlgebraicGeometry.AffineSpace.reindex_comp {n₁ n₂ n₃ : Type v} (i : n₁n₂) (j : n₂n₃) (S : Scheme) :
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                          theorem AlgebraicGeometry.AffineSpace.map_reindex {n₁ n₂ : Type v} (i : n₁n₂) {S T : Scheme} (f : S T) :
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                          theorem AlgebraicGeometry.AffineSpace.functor_obj_map (n : Type vᵒᵖ) {X✝ Y✝ : Scheme} (f : X✝ Y✝) :