Stability of finiteness conditions in commutative algebra #
In this file we show that Algebra.FiniteType
and Algebra.FinitePresentation
are
stable under base change.
theorem
Algebra.FiniteType.baseChangeAux_surj
{R : Type w₁}
[CommRing R]
{A : Type w₂}
[CommRing A]
[Algebra R A]
(B : Type w₃)
[CommRing B]
[Algebra R B]
{σ : Type u_1}
{f : MvPolynomial σ R →ₐ[R] A}
(hf : Function.Surjective ⇑f)
:
instance
Algebra.FiniteType.baseChange
{R : Type w₁}
[CommRing R]
{A : Type w₂}
[CommRing A]
[Algebra R A]
(B : Type w₃)
[CommRing B]
[Algebra R B]
[hfa : Algebra.FiniteType R A]
:
Algebra.FiniteType B (TensorProduct R B A)
instance
Algebra.FinitePresentation.baseChange
{R : Type w₁}
[CommRing R]
{A : Type w₂}
[CommRing A]
[Algebra R A]
(B : Type w₃)
[CommRing B]
[Algebra R B]
[Algebra.FinitePresentation R A]
:
Algebra.FinitePresentation B (TensorProduct R B A)