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Hironaka.Manifold.Germ.StalkGerm

The germ at a point of a section of the sheaf of C^n functions #

The stalk 𝒪_{M,a} of the sheaf of C^n functions valued in 𝕜 embeds into Filter.Germ (𝓝 a) 𝕜 through the germs at a of the extensions by zero of the sections (germAt, stalkToGerm). This module records that germAt is the germ of the extension by zero (germAt_apply) and that the germ at a of a restriction is the germ of the section (germAt_restrict).

theorem Manifold.germAt_apply {𝕜 : Type} [NontriviallyNormedField 𝕜] {EM : Type u_1} [NormedAddCommGroup EM] [NormedSpace 𝕜 EM] {HM : Type u_2} [TopologicalSpace HM] (IM : ModelWithCorners 𝕜 EM HM) (n : WithTop ℕ∞) (M : Type u) [TopologicalSpace M] [ChartedSpace HM M] (a : ↑↧M) (U : TopologicalSpace.Opens M) (ha : a ∈ U) (f : ↑((contMDiffSheafCommRing IM (modelWithCornersSelf 𝕜 𝕜) n M 𝕜).presheaf.obj (Opposite.op U))) :
(germAt IM n M a U ha) f = ↑(extendBy0 IM n M f)
theorem Manifold.germAt_restrict {𝕜 : Type} [NontriviallyNormedField 𝕜] {EM : Type u_1} [NormedAddCommGroup EM] [NormedSpace 𝕜 EM] {HM : Type u_2} [TopologicalSpace HM] (IM : ModelWithCorners 𝕜 EM HM) (n : WithTop ℕ∞) (M : Type u) [TopologicalSpace M] [ChartedSpace HM M] (a : ↑↧M) (U V : TopologicalSpace.Opens M) (i : U ⟶ V) (ha : a ∈ U) (f : ↑((contMDiffSheafCommRing IM (modelWithCornersSelf 𝕜 𝕜) n M 𝕜).presheaf.obj (Opposite.op V))) :
(germAt IM n M a U ha) ((CategoryTheory.ConcreteCategory.hom ((contMDiffSheafCommRing IM (modelWithCornersSelf 𝕜 𝕜) n M 𝕜).presheaf.map i.op)) f) = (germAt IM n M a V ⋯) f

The germs at a of restrictions are the germs of the sections.