/- Copyright 2025 The Formal Conjectures Authors. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at https://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. -/ module public import Mathlib.AlgebraicGeometry.Limits public import Mathlib.AlgebraicGeometry.ProjectiveSpectrum.Scheme public import Mathlib.RingTheory.MvPolynomial.Homogeneous@[expose] public section-- The contents of this file will be in mathlib as of #26061 universe u vopen CategoryTheory Limits MvPolynomial AlgebraicGeometryvariable (n : Type v) (S : Scheme.{max u v})local notation "ℤ[" n "]" => homogeneousSubmodule n local notation3 "ℤ[" n "].{" u "," v "}" => homogeneousSubmodule n (ULift.{max u v} )attribute [local instance] MvPolynomial.gradedAlgebra

The projective space over a scheme S, with homogeneous coordinates indexed by n

noncomputable def ProjectiveSpace : Scheme.{max u v} := pullback (terminal.from S) (terminal.from (Proj ℤ[n].{u, v}))

ℙ(n; S) is the affine S indexed by n

scoped [AlgebraicGeometry] notation "ℙ("n"; "S")" => ProjectiveSpace n S