English
The presheaf structurePresheafInCommRing on Proj, together with the glueing data, is a sheaf of commutative rings on the open sets of ProjectiveSpectrum.top 𝒜.
Русский
Предшеф struktury представлена как шеф над открытыми множествами ProjectiveSpectrum.top 𝒜 и удовлетворяет свойству склейки, т.е. шеф в комм-колцах.
LaTeX
$$$\text{structurePresheafInCommRing } 𝒜$ is a sheaf on $Proj(𝒜)$ with values in $CommRingCat$$$
Lean4
/-- `Proj` of a graded ring as a `SheafedSpace` -/
def toSheafedSpace : SheafedSpace CommRingCat
where
carrier := TopCat.of (ProjectiveSpectrum 𝒜)
presheaf := (Proj.structureSheaf 𝒜).1
IsSheaf := (Proj.structureSheaf 𝒜).2