Modules / vector spaces over localizations / fraction fields #
This file contains some results about vector spaces over the field of fractions of a ring.
Main results #
LinearIndependent.localization:bis linear independent over a localization ofRif it is linear independent overRitselfBasis.ofIsLocalizedModule/Basis.localizationLocalization: promote anR-basisbofAto anRₛ-basis ofAₛ, whereRₛandAₛare localizations ofRandAatsrespectivelyLinearIndependent.iff_fractionRing:bis linear independent overRiff it is linear independent overFrac(R)
If M has an R-basis, then localizing M at S has a basis over R localized at S.
Equations
- Module.Basis.ofIsLocalizedModule Rₛ S f b = Module.Basis.mk ⋯ ⋯
Instances For
If A has an R-basis, then localizing A at S has a basis over R localized at S.
A suitable instance for [Algebra A Aₛ] is localizationAlgebra.
Equations
- Module.Basis.localizationLocalization Rₛ S Aₛ b = Module.Basis.ofIsLocalizedModule Rₛ S (IsScalarTower.toAlgHom R A Aₛ).toLinearMap b
Instances For
An R-linear map between two S⁻¹R-modules is actually S⁻¹R-linear.
Equations
- LinearMap.extendScalarsOfIsLocalization S A f = { toFun := ⇑f, map_add' := ⋯, map_smul' := ⋯ }
Instances For
The S⁻¹R-linear maps between two S⁻¹R-modules are exactly the R-linear maps.
Equations
- LinearMap.extendScalarsOfIsLocalizationEquiv S A = { toFun := LinearMap.extendScalarsOfIsLocalization S A, map_add' := ⋯, map_smul' := ⋯, invFun := ↑R, left_inv := ⋯, right_inv := ⋯ }
Instances For
An R-linear isomorphism between S⁻¹R-modules is actually S⁻¹R-linear.
Equations
Instances For
The S⁻¹R-linear isomorphisms between two S⁻¹R-modules are exactly the R-linear
isomorphisms.
Equations
- One or more equations did not get rendered due to their size.
Instances For
A linear map M →ₗ[R] N gives a map between localized modules Mₛ →ₗ[Rₛ] Nₛ.
Equations
Instances For
An R-module isomorphism M ≃ₗ[R] N gives an Rₛ-module isomorphism Mₛ ≃ₗ[Rₛ] Nₛ.
Equations
- IsLocalizedModule.mapEquiv S f g Rₛ e = LinearEquiv.ofLinear ((IsLocalizedModule.mapExtendScalars S f g Rₛ) ↑e) ((IsLocalizedModule.mapExtendScalars S g f Rₛ) ↑e.symm) ⋯ ⋯
Instances For
A linear map M →ₗ[R] N gives a map between localized modules Mₛ →ₗ[Rₛ] Nₛ.