Module

ResidueDegree.lean

Nyll.SchemeTheory.AbhyankarLemma.TameRamification.ValueGroup.NonarchimedeanLocalField.ResidueDegree
10 declarations indexed from sourceView source ↗

Neu1999 residue-degree lcm divisibility

This file extracts concrete residue-degree divisibility from the Neu1999 field-norm value-image comparison.

Declarations

TameAbhyankar.NAField.lcm_residueDegree_dvd_common_residueDegree_towers

Common-top residue-degree divisibility generated by the Neu1999 field-norm value images. The valuation image of N_{M/K}(Mˣ) is generated by f(K,M), while the same image lies in the lcm value-step subgroup generated by f(K,L) and f(K,L').

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem lcm_residueDegree_dvd_common_residueDegree_towers :
    ((((Module.finrank 𝓀[K] 𝓀[L] : ℤ).lcm
      (Module.finrank 𝓀[K] 𝓀[L'] : ℤ) : ℕ) : ℤ) ∣
        (Module.finrank 𝓀[K] 𝓀[M] : ℤ))
TameAbhyankar.NAField.intLcm_residueDegree_dvd_common_residueDegree_towers_nat

Nat divisibility form of lcm_residueDegree_dvd_common_residueDegree_towers, keeping the same integer-lcm source step on the left.

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem intLcm_residueDegree_dvd_common_residueDegree_towers_nat :
    ((Module.finrank 𝓀[K] 𝓀[L] : ℤ).lcm
      (Module.finrank 𝓀[K] 𝓀[L'] : ℤ) : ℕ) ∣
        Module.finrank 𝓀[K] 𝓀[M]
TameAbhyankar.NAField.nat_lcm_residueDegree_dvd_common_residueDegree_towers

Standard Nat.lcm form of the common-top Neu1999 residue-degree divisibility.

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem nat_lcm_residueDegree_dvd_common_residueDegree_towers :
    Nat.lcm (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank 𝓀[K] 𝓀[M]
TameAbhyankar.NAField.nat_lcm_residueDegree_dvd_common_residueDegree_towers_from_norm_generator

Element-generator proof of the common-top residue-degree divisibility: fieldNormSubgroup K M contains an element of valuation f(K,M), and the common-top norm-image theorem forces that valuation to be divisible by the lower residue-degree lcm.

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem nat_lcm_residueDegree_dvd_common_residueDegree_towers_from_norm_generator :
    Nat.lcm (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank 𝓀[K] 𝓀[M]
TameAbhyankar.NAField.nat_lcm_residueDegree_dvd_common_finrank_towers

The common-top field degree is also divisible by the lower residue-degree lcm, because Neu1999's common residue degree divides [M : K].

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem nat_lcm_residueDegree_dvd_common_finrank_towers :
    Nat.lcm (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank K M
TameAbhyankar.NAField.ramificationIndex_mul_nat_lcm_residueDegree_dvd_common_finrank_towers

The common-top field degree is divisible by the common-top ramification index times the lower residue-degree lcm. This is the Neu1999 e * f = [M : K] relation applied after the norm-image theorem produces lcm (f K L) (f K L') ∣ f K M.

Source context 28 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem ramificationIndex_mul_nat_lcm_residueDegree_dvd_common_finrank_towers :
    (𝓂[M] : Ideal 𝒪[M]).ramificationIdx 𝒪[K] *
        Nat.lcm (Module.finrank 𝓀[K] 𝓀[L])
          (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank K M
TameAbhyankar.NAField.nat_lcm_residueDegree_dvd_common_finrank_towers_from_base_norm

Element-generator proof of the common-top field-degree divisibility: the base uniformizer produces a concrete member of fieldNormSubgroup K M with valuation [M : K], and the common-top norm-image theorem forces the same valuation to be divisible by the lower residue-degree lcm.

Source context 29 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section CommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [FiniteDimensional K M]
variable [Algebra.IsSeparable K L] [Algebra.IsSeparable K L']
variable [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
omit [ValuativeRel M] [TopologicalSpace M] [IsNonarchimedeanLocalField M]
    [FiniteDimensional K M] [Algebra.IsSeparable K M]
    [Valuation.HasExtension (ValuativeRel.valuation K)
      (ValuativeRel.valuation M)] in
theorem nat_lcm_residueDegree_dvd_common_finrank_towers_from_base_norm :
    Nat.lcm (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank K M
TameAbhyankar.NAField.nat_lcm_galoisResidueDegree_dvd_common_residueDegree_towers

With both lower branches supplied by Neu1999 Galois valuation data, the common-top residue degree is divisible by the lcm of the lower Galois residue degrees.

Source context 27 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section GaloisLowerCommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [IsGalois K L] [IsGalois K L']
variable [FiniteDimensional K M] [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem nat_lcm_galoisResidueDegree_dvd_common_residueDegree_towers :
    Nat.lcm
        (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank 𝓀[K] 𝓀[M]
TameAbhyankar.NAField.nat_lcm_galoisResidueDegree_dvd_common_finrank_towers

Field-degree form of the Galois lower-branch residue-degree lcm source.

Source context 27 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section GaloisLowerCommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [IsGalois K L] [IsGalois K L']
variable [FiniteDimensional K M] [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem nat_lcm_galoisResidueDegree_dvd_common_finrank_towers :
    Nat.lcm
        (Module.finrank 𝓀[K] 𝓀[L])
        (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank K M
TameAbhyankar.NAField.ramificationIndex_mul_nat_lcm_galoisResidueDegree_dvd_common_finrank_towers

The common-top ramification index times the lower Galois residue-degree lcm divides the common-top field degree.

Source context 27 commands

Surrounding namespaces, section variables, and local commands at this declaration.

noncomputable section
universe u
namespace TameAbhyankar
open LocalFieldTheory.DiscreteValuationField
open scoped ValuativeRel
namespace NAField
section GaloisLowerCommonTopResidueDegree
variable {K L L' M : Type u}
variable [Field K] [ValuativeRel K] [TopologicalSpace K]
variable [IsNonarchimedeanLocalField K]
variable [Field L] [ValuativeRel L] [TopologicalSpace L]
variable [IsNonarchimedeanLocalField L]
variable [Field L'] [ValuativeRel L'] [TopologicalSpace L']
variable [IsNonarchimedeanLocalField L']
variable [Field M] [ValuativeRel M] [TopologicalSpace M]
variable [IsNonarchimedeanLocalField M]
variable [Algebra K L] [Algebra K L']
variable [Algebra K M]
variable [Algebra L M] [Algebra L' M]
variable [IsScalarTower K L M] [IsScalarTower K L' M]
variable [Module.Free L M] [Module.Free L' M]
variable [FiniteDimensional K L] [FiniteDimensional K L']
variable [IsGalois K L] [IsGalois K L']
variable [FiniteDimensional K M] [Algebra.IsSeparable K M]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L)]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation L')]
variable [Valuation.HasExtension (ValuativeRel.valuation K)
  (ValuativeRel.valuation M)]
theorem ramificationIndex_mul_nat_lcm_galoisResidueDegree_dvd_common_finrank_towers :
    (𝓂[M] : Ideal 𝒪[M]).ramificationIdx 𝒪[K] *
        Nat.lcm
          (Module.finrank 𝓀[K] 𝓀[L])
          (Module.finrank 𝓀[K] 𝓀[L']) ∣
      Module.finrank K M