Module

FieldNorm.lean

Nyll.ValuedFieldTheory.LocalField.DiscreteValuationField.FieldNorm
118 declarations indexed from sourceView source ↗

Field norm on unit groups

This file connects mathlib's Algebra.norm with the unit-group and valued-norm APIs used by local CFT.

Declarations

LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup

The norm subgroup of Kˣ attached to L/K.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormSubgroup : Subgroup Kˣ
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_le_of_tower

The norm subgroup from the top field of a tower lies in the norm subgroup from the intermediate field.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_le_of_tower
    (E : Type w) [Field E] [Algebra K E] [Algebra E L] [IsScalarTower K E L]
    [Module.Free E L] :
    fieldNormSubgroup K L ≤ fieldNormSubgroup K E
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_eq_top_iff

Characterizes fieldNormSubgroup K L = ⊤ by the equivalent condition Function.Surjective (normUnits K L).

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_eq_top_iff :
    fieldNormSubgroup K L = ⊤ ↔ Function.Surjective (normUnits K L)
LocalFieldTheory.DiscreteValuationField.mem_fieldNormUnits_ker_iff_norm_eq_one

Characterizes z ∈ MonoidHom.ker (normUnits K L) by the equivalent condition Algebra.norm K (z : L) = 1.

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem mem_fieldNormUnits_ker_iff_norm_eq_one (z : Lˣ) :
    z ∈ MonoidHom.ker (normUnits K L) ↔
      Algebra.norm K (z : L) = 1
LocalFieldTheory.DiscreteValuationField.fieldNormUnitsQuotientKerEquivFieldNormSubgroup

First-isomorphism-theorem form for the field norm on unit groups: Lˣ / ker(N) is the norm subgroup of Kˣ.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormUnitsQuotientKerEquivFieldNormSubgroup :
    Lˣ ⧸ MonoidHom.ker (normUnits K L) ≃*
      fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormUnitsQuotientKerEquivFieldNormSubgroup_mk

Establishes the identity fieldNormUnitsQuotientKerEquivFieldNormSubgroup K L (QuotientGroup.mk' (MonoidHom.ker (normUnits K L)) z) = (normUnits K L).rangeRestrict z.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormUnitsQuotientKerEquivFieldNormSubgroup_mk
    (z : Lˣ) :
    fieldNormUnitsQuotientKerEquivFieldNormSubgroup K L
        (QuotientGroup.mk'
          (MonoidHom.ker (normUnits K L)) z) =
      (normUnits K L).rangeRestrict z
LocalFieldTheory.DiscreteValuationField.coe_fieldNormUnitsQuotientKerEquivFieldNormSubgroup_mk

Establishes the identity ((fieldNormUnitsQuotientKerEquivFieldNormSubgroup K L (QuotientGroup.mk' (MonoidHom.ker (normUnits K L)) z) : fieldNormSubgroup K L) : Kˣ) = normUnits K L z.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem coe_fieldNormUnitsQuotientKerEquivFieldNormSubgroup_mk
    (z : Lˣ) :
    ((fieldNormUnitsQuotientKerEquivFieldNormSubgroup K L
        (QuotientGroup.mk'
          (MonoidHom.ker (normUnits K L)) z) :
        fieldNormSubgroup K L) : Kˣ) =
      normUnits K L z
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap

The quotient map Kˣ → Kˣ / N_{L/K}(Lˣ) attached to the field norm.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormQuotientMap :
    Kˣ →* Kˣ ⧸ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap_apply

The defining evaluation formula for fieldNormQuotientMap is fieldNormQuotientMap K L x = QuotientGroup.mk' (fieldNormSubgroup K L) x.

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientMap_apply (x : Kˣ) :
    fieldNormQuotientMap K L x =
      QuotientGroup.mk' (fieldNormSubgroup K L) x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap_ker

The kernel of the norm quotient map is exactly the field-norm subgroup.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientMap_ker :
    MonoidHom.ker (fieldNormQuotientMap K L) = fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap_eq_one_iff

Characterizes fieldNormQuotientMap K L x = 1 by the equivalent condition x ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientMap_eq_one_iff (x : Kˣ) :
    fieldNormQuotientMap K L x = 1 ↔
      x ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap_eq_one_iff_exists_norm_eq

Characterizes fieldNormQuotientMap K L x = 1 by the equivalent condition ∃ z : Lˣ, normUnits K L z = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientMap_eq_one_iff_exists_norm_eq (x : Kˣ) :
    fieldNormQuotientMap K L x = 1 ↔
      ∃ z : Lˣ, normUnits K L z = x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientMap_eq_iff_div_mem

Characterizes fieldNormQuotientMap K L x = fieldNormQuotientMap K L y by the equivalent condition x / y ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientMap_eq_iff_div_mem (x y : Kˣ) :
    fieldNormQuotientMap K L x = fieldNormQuotientMap K L y ↔
      x / y ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_div_mem_iff_inv_mul_mem

Characterizes x / y ∈ fieldNormSubgroup K L by the equivalent condition y⁻¹ * x ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_div_mem_iff_inv_mul_mem (x y : Kˣ) :
    x / y ∈ fieldNormSubgroup K L ↔
      y⁻¹ * x ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_inv_mul_mem_iff_div_mem

Characterizes y⁻¹ * x ∈ fieldNormSubgroup K L by the equivalent condition x / y ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_inv_mul_mem_iff_div_mem (x y : Kˣ) :
    y⁻¹ * x ∈ fieldNormSubgroup K L ↔
      x / y ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_div_mem_iff_exists_norm_mul_eq

Characterizes x / y ∈ fieldNormSubgroup K L by the equivalent condition ∃ z : Lˣ, normUnits K L z * y = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_div_mem_iff_exists_norm_mul_eq
    (x y : Kˣ) :
    x / y ∈ fieldNormSubgroup K L ↔
      ∃ z : Lˣ, normUnits K L z * y = x
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_inv_mul_mem_iff_exists_mul_norm_eq

Characterizes y⁻¹ * x ∈ fieldNormSubgroup K L by the equivalent condition ∃ z : Lˣ, y * normUnits K L z = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_inv_mul_mem_iff_exists_mul_norm_eq
    (x y : Kˣ) :
    y⁻¹ * x ∈ fieldNormSubgroup K L ↔
      ∃ z : Lˣ, y * normUnits K L z = x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_one_iff

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 by the equivalent condition x ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_one_iff (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 ↔
      x ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_one_iff_exists_norm_eq

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 by the equivalent condition ∃ z : Lˣ, normUnits K L z = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_one_iff_exists_norm_eq (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 ↔
      ∃ z : Lˣ, normUnits K L z = x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_norm_mk_eq_one

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z) = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_norm_mk_eq_one (z : Lˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L)
        (normUnits K L z) = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_pow_eq_one_iff_pow_mem

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 by the equivalent condition x ^ n ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_pow_eq_one_iff_pow_mem
    (x : Kˣ) (n : ℕ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 ↔
      x ^ n ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_pow_eq_one_iff_exists_norm_eq_pow

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 by the equivalent condition ∃ z : Lˣ, normUnits K L z = x ^ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_pow_eq_one_iff_exists_norm_eq_pow
    (x : Kˣ) (n : ℕ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 ↔
      ∃ z : Lˣ, normUnits K L z = x ^ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_pow_eq_one_iff_exists_pow_mem

Characterizes q ^ n = 1 by the equivalent condition ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧ x ^ n ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_pow_eq_one_iff_exists_pow_mem
    (q : Kˣ ⧸ fieldNormSubgroup K L) (n : ℕ) :
    q ^ n = 1 ↔
      ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧
        x ^ n ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_pow_eq_one_iff_exists_norm_eq_pow

Characterizes q ^ n = 1 by the equivalent condition ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧ ∃ z : Lˣ, normUnits K L z = x ^ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_pow_eq_one_iff_exists_norm_eq_pow
    (q : Kˣ ⧸ fieldNormSubgroup K L) (n : ℕ) :
    q ^ n = 1 ↔
      ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧
        ∃ z : Lˣ, normUnits K L z = x ^ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_zpow_eq_one_iff_zpow_mem

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 by the equivalent condition x ^ n ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_zpow_eq_one_iff_zpow_mem
    (x : Kˣ) (n : ℤ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 ↔
      x ^ n ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_zpow_eq_one_iff_exists_norm_eq_zpow

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 by the equivalent condition ∃ z : Lˣ, normUnits K L z = x ^ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_zpow_eq_one_iff_exists_norm_eq_zpow
    (x : Kˣ) (n : ℤ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) x) ^ n = 1 ↔
      ∃ z : Lˣ, normUnits K L z = x ^ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_zpow_eq_one_iff_exists_zpow_mem

Characterizes q ^ n = 1 by the equivalent condition ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧ x ^ n ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_zpow_eq_one_iff_exists_zpow_mem
    (q : Kˣ ⧸ fieldNormSubgroup K L) (n : ℤ) :
    q ^ n = 1 ↔
      ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧
        x ^ n ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_zpow_eq_one_iff_exists_norm_eq_zpow

Characterizes q ^ n = 1 by the equivalent condition ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧ ∃ z : Lˣ, normUnits K L z = x ^ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_zpow_eq_one_iff_exists_norm_eq_zpow
    (q : Kˣ ⧸ fieldNormSubgroup K L) (n : ℤ) :
    q ^ n = 1 ↔
      ∃ x : Kˣ, QuotientGroup.mk' (fieldNormSubgroup K L) x = q ∧
        ∃ z : Lˣ, normUnits K L z = x ^ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_div_mem

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition x / y ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_div_mem (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      x / y ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_inv_mul_mem

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition y⁻¹ * x ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_inv_mul_mem (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      y⁻¹ * x ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_exists_norm_eq_div

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition ∃ z : Lˣ, normUnits K L z = x / y.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_exists_norm_eq_div
    (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      ∃ z : Lˣ, normUnits K L z = x / y
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_exists_norm_eq_inv_mul

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition ∃ z : Lˣ, normUnits K L z = y⁻¹ * x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_exists_norm_eq_inv_mul
    (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      ∃ z : Lˣ, normUnits K L z = y⁻¹ * x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_exists_norm_mul_eq

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition ∃ z : Lˣ, normUnits K L z * y = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_exists_norm_mul_eq (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      ∃ z : Lˣ, normUnits K L z * y = x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_exists_mul_norm_eq

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition ∃ z : Lˣ, y * normUnits K L z = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_exists_mul_norm_eq (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      ∃ z : Lˣ, y * normUnits K L z = x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_norm_mul_mk_eq

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z * x) = QuotientGroup.mk' (fieldNormSubgroup K L) x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_norm_mul_mk_eq (z : Lˣ) (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L)
        (normUnits K L z * x) =
      QuotientGroup.mk' (fieldNormSubgroup K L) x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mul_norm_mk_eq

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) (x * normUnits K L z) = QuotientGroup.mk' (fieldNormSubgroup K L) x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mul_norm_mk_eq (x : Kˣ) (z : Lˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L)
        (x * normUnits K L z) =
      QuotientGroup.mk' (fieldNormSubgroup K L) x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_mul_norm_eq

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) x * QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z) = QuotientGroup.mk' (fieldNormSubgroup K L) x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_mul_norm_eq (x : Kˣ) (z : Lˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x *
        QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z) =
      QuotientGroup.mk' (fieldNormSubgroup K L) x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_norm_mul_mk_eq_mk

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z) * QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_norm_mul_mk_eq_mk (z : Lˣ) (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) (normUnits K L z) *
        QuotientGroup.mk' (fieldNormSubgroup K L) x =
      QuotientGroup.mk' (fieldNormSubgroup K L) x
LocalFieldTheory.DiscreteValuationField.fieldNormUnits_algebraMap

Norm of an element coming from the base field.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormUnits_algebraMap (u : Kˣ) :
    normUnits K L (Units.map (algebraMap K L).toMonoidHom u) =
      u ^ Module.finrank K L
LocalFieldTheory.DiscreteValuationField.fieldNormUnits_algebraMap_of_finrank_eq_one

Establishes the identity normUnits K L (Units.map (algebraMap K L).toMonoidHom u) = u.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormUnits_algebraMap_of_finrank_eq_one
    (hfin : Module.finrank K L = 1) (u : Kˣ) :
    normUnits K L (Units.map (algebraMap K L).toMonoidHom u) = u
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_pow_finrank_mem

Establishes the membership statement u ^ Module.finrank K L ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_pow_finrank_mem (u : Kˣ) :
    u ^ Module.finrank K L ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_eq_top_of_finrank_eq_one

Establishes the identity fieldNormSubgroup K L = ⊤.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_eq_top_of_finrank_eq_one
    (hfin : Module.finrank K L = 1) :
    fieldNormSubgroup K L = ⊤
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_pow_finrank_eq_one

Establishes the identity (QuotientGroup.mk' (fieldNormSubgroup K L) u) ^ Module.finrank K L = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_pow_finrank_eq_one (u : Kˣ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) u) ^
        Module.finrank K L = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_pow_finrank_eq_one

Establishes the identity q ^ Module.finrank K L = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_pow_finrank_eq_one
    (q : Kˣ ⧸ fieldNormSubgroup K L) :
    q ^ Module.finrank K L = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_pow_eq_one_of_finrank_dvd

Establishes the identity (QuotientGroup.mk' (fieldNormSubgroup K L) u) ^ n = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_pow_eq_one_of_finrank_dvd
    {n : ℕ} (hn : Module.finrank K L ∣ n) (u : Kˣ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) u) ^ n = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_pow_eq_one_of_finrank_dvd

Establishes the identity q ^ n = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_pow_eq_one_of_finrank_dvd
    {n : ℕ} (hn : Module.finrank K L ∣ n)
    (q : Kˣ ⧸ fieldNormSubgroup K L) :
    q ^ n = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_eq_one_of_finrank_eq_one

Establishes the identity q = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_eq_one_of_finrank_eq_one
    (hfin : Module.finrank K L = 1)
    (q : Kˣ ⧸ fieldNormSubgroup K L) :
    q = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_eq_of_finrank_eq_one

Establishes the identity q = r.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_eq_of_finrank_eq_one
    (hfin : Module.finrank K L = 1)
    (q r : Kˣ ⧸ fieldNormSubgroup K L) :
    q = r
LocalFieldTheory.DiscreteValuationField.valuedFieldNorm

Package a field norm as a ValuedNorm once the valuation formula has been proved for the concrete extension. The natural-number argument is not a second source of extension-invariant data: hformula certifies it as the valuation multiplier (and a source uniformizer makes that multiplier unique).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def valuedFieldNorm
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x) :
    ValuedNorm vK vL where
  toHom := normUnits K L
  residueDegree := residueDegree
  valuation_formula := hformula
LocalFieldTheory.DiscreteValuationField.valuedFieldNorm_toHom

Establishes the identity (valuedFieldNorm K L vK vL residueDegree hformula).toHom = normUnits K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem valuedFieldNorm_toHom
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x) :
    (valuedFieldNorm K L vK vL residueDegree hformula).toHom =
      normUnits K L
LocalFieldTheory.DiscreteValuationField.valuedFieldNorm_normSubgroup_eq_fieldNormSubgroup

Establishes the identity (valuedFieldNorm K L vK vL residueDegree hformula).normSubgroup = fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem valuedFieldNorm_normSubgroup_eq_fieldNormSubgroup
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x) :
    (valuedFieldNorm K L vK vL residueDegree hformula).normSubgroup =
      fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientEquivZMod

Concrete cyclic description of the field-norm quotient. The assumptions are the valuation formula for the field norm and the assertion that every target valuation-zero element is already a field norm.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormQuotientEquivZMod
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    Kˣ ⧸ fieldNormSubgroup K L ≃* Multiplicative (ZMod residueDegree)
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientEquivZMod_mk

Establishes the identity fieldNormQuotientEquivZMod K L vK vL residueDegree hformula hϖK hϖL hzero (QuotientGroup.mk' (fieldNormSubgroup K L) x) = Multiplicative.ofAdd ((vK.val x : ℤ) : ZMod residueDegree).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientEquivZMod_mk
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x : Kˣ) :
    fieldNormQuotientEquivZMod K L vK vL residueDegree
        hformula hϖK hϖL hzero
        (QuotientGroup.mk' (fieldNormSubgroup K L) x) =
      Multiplicative.ofAdd ((vK.val x : ℤ) : ZMod residueDegree)
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientEquivZMod_uniformizer_zpow

fieldNormQuotientEquivZMod_uniformizer satisfies the integer-power formula fieldNormQuotientEquivZMod K L vK vL residueDegree hformula hϖK hϖL hzero (QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n)) = Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientEquivZMod_uniformizer_zpow
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (n : ℤ) :
    fieldNormQuotientEquivZMod K L vK vL residueDegree
        hformula hϖK hϖL hzero
        (QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n)) =
      Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree)
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientEquivZMod_uniformizerClass_zpow

fieldNormQuotientEquivZMod_uniformizerClass satisfies the integer-power formula fieldNormQuotientEquivZMod K L vK vL residueDegree hformula hϖK hϖL hzero ((QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n) = Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientEquivZMod_uniformizerClass_zpow
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (n : ℤ) :
    fieldNormQuotientEquivZMod K L vK vL residueDegree
        hformula hϖK hϖL hzero
        ((QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n) =
      Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree)
LocalFieldTheory.DiscreteValuationField.fieldNormQuotientEquivZMod_symm_mk_ofAdd

Establishes the identity (fieldNormQuotientEquivZMod K L vK vL residueDegree hformula hϖK hϖL hzero).symm (Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree)) = QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotientEquivZMod_symm_mk_ofAdd
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (n : ℤ) :
    (fieldNormQuotientEquivZMod K L vK vL residueDegree
        hformula hϖK hϖL hzero).symm
        (Multiplicative.ofAdd ((n : ℤ) : ZMod residueDegree)) =
      QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n)
LocalFieldTheory.DiscreteValuationField.cardinalMk_fieldNormQuotient_eq_residueDegree

Cardinality form of the concrete field-norm quotient computation.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem cardinalMk_fieldNormQuotient_eq_residueDegree
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    [NeZero residueDegree] :
    Cardinal.mk (Kˣ ⧸ fieldNormSubgroup K L) = residueDegree
LocalFieldTheory.DiscreteValuationField.exists_mem_fieldNormSubgroup_val_eq_iff_residueDegree_dvd

Field-norm value-image criterion: an integer is attained as the valuation of a field norm exactly when it is divisible by the residue degree.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_mem_fieldNormSubgroup_val_eq_iff_residueDegree_dvd
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL) (n : ℤ) :
    (∃ x : Kˣ, x ∈ fieldNormSubgroup K L ∧ vK.val x = n) ↔
      (residueDegree : ℤ) ∣ n
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_valueImage_eq_residueDegree

The value image of the field-norm subgroup is exactly fℤ.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_valueImage_eq_residueDegree
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL) :
    vK.subgroupValueSubgroup (fieldNormSubgroup K L) =
      integerMultipleSubgroup (residueDegree : ℤ)
LocalFieldTheory.DiscreteValuationField.mem_fieldNormSubgroup_iff_residueDegree_dvd_val_of_zeroSubgroup_le

Characterizes x ∈ fieldNormSubgroup K L by the equivalent condition (residueDegree : ℤ) ∣ vK.val x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem mem_fieldNormSubgroup_iff_residueDegree_dvd_val_of_zeroSubgroup_le
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) (x : Kˣ) :
    x ∈ fieldNormSubgroup K L ↔ (residueDegree : ℤ) ∣ vK.val x
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_residueDegree_dvd_val_of_mem

Establishes the divisibility statement (residueDegree : ℤ) ∣ vK.val x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_residueDegree_dvd_val_of_mem
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {x : Kˣ} (hx : x ∈ fieldNormSubgroup K L) :
    (residueDegree : ℤ) ∣ vK.val x
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_mem_of_residueDegree_dvd_val_of_zeroSubgroup_le

Establishes the membership statement x ∈ fieldNormSubgroup K L.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_mem_of_residueDegree_dvd_val_of_zeroSubgroup_le
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    {x : Kˣ} (hx : (residueDegree : ℤ) ∣ vK.val x) :
    x ∈ fieldNormSubgroup K L
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_div_mem_iff_residueDegree_dvd_valuation_difference

Characterizes x / y ∈ fieldNormSubgroup K L by the equivalent condition (residueDegree : ℤ) ∣ vK.val x - vK.val y.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_div_mem_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    x / y ∈ fieldNormSubgroup K L ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_inv_mul_mem_iff_residueDegree_dvd_valuation_difference

Characterizes y⁻¹ * x ∈ fieldNormSubgroup K L by the equivalent condition (residueDegree : ℤ) ∣ vK.val x - vK.val y.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_inv_mul_mem_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    y⁻¹ * x ∈ fieldNormSubgroup K L ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.exists_fieldNormUnits_eq_iff_residueDegree_dvd_val

Under the standard valuation formula and valuation-zero norm-surjectivity, the norm equation N z = x is solvable exactly when f divides v(x).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_fieldNormUnits_eq_iff_residueDegree_dvd_val
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) (x : Kˣ) :
    (∃ z : Lˣ, normUnits K L z = x) ↔
      (residueDegree : ℤ) ∣ vK.val x
LocalFieldTheory.DiscreteValuationField.exists_fieldNormUnits_eq_of_residueDegree_dvd_val

Establishes the identity ∃ z : Lˣ, normUnits K L z = x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_fieldNormUnits_eq_of_residueDegree_dvd_val
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    {x : Kˣ} (hx : (residueDegree : ℤ) ∣ vK.val x) :
    ∃ z : Lˣ, normUnits K L z = x
LocalFieldTheory.DiscreteValuationField.exists_fieldNormUnits_eq_div_iff_residueDegree_dvd_valuation_difference

Difference form of the concrete norm equation criterion.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_fieldNormUnits_eq_div_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    (∃ z : Lˣ, normUnits K L z = x / y) ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.exists_fieldNormUnits_mul_eq_iff_residueDegree_dvd_valuation_difference

Multiplicative equation form of the concrete norm-lift criterion.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_fieldNormUnits_mul_eq_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    (∃ z : Lˣ, normUnits K L z * y = x) ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.exists_mul_fieldNormUnits_eq_iff_residueDegree_dvd_valuation_difference

Left-multiplicative equation form of the concrete norm-lift criterion.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem exists_mul_fieldNormUnits_eq_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    (∃ z : Lˣ, y * normUnits K L z = x) ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_one_iff_residueDegree_dvd_val

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 by the equivalent condition (residueDegree : ℤ) ∣ vK.val x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_one_iff_residueDegree_dvd_val
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x = 1 ↔
      (residueDegree : ℤ) ∣ vK.val x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_iff_residueDegree_dvd_valuation_difference

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) y by the equivalent condition (residueDegree : ℤ) ∣ vK.val x - vK.val y.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_iff_residueDegree_dvd_valuation_difference
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x y : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) y ↔
      (residueDegree : ℤ) ∣ vK.val x - vK.val y
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_uniformizer_zpow_mem_iff

Characterizes ϖK ^ n ∈ fieldNormSubgroup K L by the equivalent condition (residueDegree : ℤ) ∣ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_uniformizer_zpow_mem_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (n : ℤ) :
    ϖK ^ n ∈ fieldNormSubgroup K L ↔
      (residueDegree : ℤ) ∣ n
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_uniformizer_zpow_div_mem_iff

Characterizes ϖK ^ m / ϖK ^ n ∈ fieldNormSubgroup K L by the equivalent condition (residueDegree : ℤ) ∣ m - n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_uniformizer_zpow_div_mem_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (m n : ℤ) :
    ϖK ^ m / ϖK ^ n ∈ fieldNormSubgroup K L ↔
      (residueDegree : ℤ) ∣ m - n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_uniformizer_zpow_val

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ vK.val x).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_uniformizer_zpow_val
    (vK : MultiplicativeIntegerValuation Kˣ)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
      QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ vK.val x)
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_uniformizerClass_zpow_val

Establishes the identity QuotientGroup.mk' (fieldNormSubgroup K L) x = (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ vK.val x.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_uniformizerClass_zpow_val
    (vK : MultiplicativeIntegerValuation Kˣ)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) (x : Kˣ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
      (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ vK.val x
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_uniformizer_zpow_iff

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n) by the equivalent condition (residueDegree : ℤ) ∣ vK.val x - n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_uniformizer_zpow_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x : Kˣ) (n : ℤ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        QuotientGroup.mk' (fieldNormSubgroup K L) (ϖK ^ n) ↔
      (residueDegree : ℤ) ∣ vK.val x - n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_mk_eq_uniformizerClass_zpow_iff

Characterizes QuotientGroup.mk' (fieldNormSubgroup K L) x = (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n by the equivalent condition (residueDegree : ℤ) ∣ vK.val x - n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_mk_eq_uniformizerClass_zpow_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (x : Kˣ) (n : ℤ) :
    QuotientGroup.mk' (fieldNormSubgroup K L) x =
        (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n ↔
      (residueDegree : ℤ) ∣ vK.val x - n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_uniformizerClass_zpow_eq_iff

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ m = (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n by the equivalent condition (residueDegree : ℤ) ∣ m - n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_uniformizerClass_zpow_eq_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (m n : ℤ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ m =
        (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n ↔
      (residueDegree : ℤ) ∣ m - n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_uniformizerClass_zpow_eq_one_iff

Characterizes (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n = 1 by the equivalent condition (residueDegree : ℤ) ∣ n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_uniformizerClass_zpow_eq_one_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (n : ℤ) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n = 1 ↔
      (residueDegree : ℤ) ∣ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_uniformizerClass_zpow_residueDegree_eq_one

Establishes the identity (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ (residueDegree : ℤ) = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_uniformizerClass_zpow_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^
        (residueDegree : ℤ) = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_generated_by_uniformizerClass

The concrete field-norm quotient is generated by the class of any target uniformizer under the standard valuation-zero norm-surjectivity hypothesis.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_generated_by_uniformizerClass
    (vK : MultiplicativeIntegerValuation Kˣ)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (q : Kˣ ⧸ fieldNormSubgroup K L) :
    ∃ n : ℤ,
      q = (QuotientGroup.mk' (fieldNormSubgroup K L) ϖK) ^ n
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_closure_uniformizerClass_eq_top

Establishes the identity Subgroup.closure ({QuotientGroup.mk' (fieldNormSubgroup K L) ϖK} : Set (Kˣ ⧸ fieldNormSubgroup K L)) = ⊤.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_closure_uniformizerClass_eq_top
    (vK : MultiplicativeIntegerValuation Kˣ)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    Subgroup.closure
        ({QuotientGroup.mk' (fieldNormSubgroup K L) ϖK} :
          Set (Kˣ ⧸ fieldNormSubgroup K L)) =
      ⊤
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_eq_top_of_residueDegree_eq_one

Establishes the identity fieldNormSubgroup K L = ⊤.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_eq_top_of_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (hres : residueDegree = 1) :
    fieldNormSubgroup K L = ⊤
LocalFieldTheory.DiscreteValuationField.fieldNormUnits_surjective_of_residueDegree_eq_one

The specified map is surjective: Function.Surjective (normUnits K L).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormUnits_surjective_of_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (hres : residueDegree = 1) :
    Function.Surjective (normUnits K L)
LocalFieldTheory.DiscreteValuationField.fieldNormUnits_surjective_iff_residueDegree_eq_one

Under the standard valuation formula and valuation-zero norm-surjectivity, the field norm on units is surjective exactly in residue degree one.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormUnits_surjective_iff_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    Function.Surjective (normUnits K L) ↔ residueDegree = 1
LocalFieldTheory.DiscreteValuationField.fieldNormSubgroup_eq_top_iff_residueDegree_eq_one

Subgroup form of the residue-degree-one norm-surjectivity criterion.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormSubgroup_eq_top_iff_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    fieldNormSubgroup K L = ⊤ ↔ residueDegree = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_eq_one_of_residueDegree_eq_one

Establishes the identity q = 1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_eq_one_of_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (hres : residueDegree = 1)
    (q : Kˣ ⧸ fieldNormSubgroup K L) :
    q = 1
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_eq_of_residueDegree_eq_one

Establishes the identity q = r.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_eq_of_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L)
    (hres : residueDegree = 1)
    (q r : Kˣ ⧸ fieldNormSubgroup K L) :
    q = r
LocalFieldTheory.DiscreteValuationField.fieldNormQuotient_forall_eq_one_iff_residueDegree_eq_one

Quotient form of the residue-degree-one norm-surjectivity criterion.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormQuotient_forall_eq_one_iff_residueDegree_eq_one
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    {ϖK : Kˣ} (hϖK : vK.IsUniformizer ϖK)
    {ϖL : Lˣ} (hϖL : vL.IsUniformizer ϖL)
    (hzero : vK.zeroSubgroup ≤ fieldNormSubgroup K L) :
    (∀ q : Kˣ ⧸ fieldNormSubgroup K L, q = 1) ↔ residueDegree = 1
LocalFieldTheory.DiscreteValuationField.fieldNormMapsFiltrationLevels

Concrete compatibility condition saying that the field norm maps the n-th source principal-unit subgroup into the requested target level.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
abbrev fieldNormMapsFiltrationLevels
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) : Prop
LocalFieldTheory.DiscreteValuationField.valuedFieldNorm_mapsFiltrationLevels_iff

Characterizes ValuedNorm.MapsFiltrationLevels (valuedFieldNorm K L vK vL residueDegree hformula) UK UL targetLevel by the equivalent condition fieldNormMapsFiltrationLevels K L UK UL targetLevel.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem valuedFieldNorm_mapsFiltrationLevels_iff
    (vK : MultiplicativeIntegerValuation Kˣ)
    (vL : MultiplicativeIntegerValuation Lˣ)
    (residueDegree : ℕ)
    (hformula :
      ∀ x : Lˣ, vK.val (normUnits K L x) =
        (residueDegree : ℤ) * vL.val x)
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) :
    ValuedNorm.MapsFiltrationLevels
        (valuedFieldNorm K L vK vL residueDegree hformula)
        UK UL targetLevel ↔
      fieldNormMapsFiltrationLevels K L UK UL targetLevel
LocalFieldTheory.DiscreteValuationField.fieldNormMapsFiltrationLevels_of_le

Filtration compatibility can be weakened by replacing the target level by a coarser one.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormMapsFiltrationLevels_of_le
    {UK : AntitoneSubgroupFiltration Kˣ} {UL : AntitoneSubgroupFiltration Lˣ}
    {targetLevel targetLevel' : ℕ → ℕ}
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel)
    (hle : ∀ n, targetLevel' n ≤ targetLevel n) :
    fieldNormMapsFiltrationLevels K L UK UL targetLevel'
LocalFieldTheory.DiscreteValuationField.fieldNormMapLevelOfMapsFiltrationLevels

The field norm restricted to a principal-unit filtration level.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormMapLevelOfMapsFiltrationLevels
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ) :
    UL.principalUnitSubgroup n →*
      UK.principalUnitSubgroup (targetLevel n) where
  toFun x := ⟨normUnits K L x.1, hN n x.2⟩
  map_one' := by
    apply Subtype.ext
    exact (normUnits K L).map_one
  map_mul' x y := by
    apply Subtype.ext
    exact (normUnits K L).map_mul x.1 y.1
LocalFieldTheory.DiscreteValuationField.fieldNormMapLevelOfMapsFiltrationLevels_apply

The defining evaluation formula for fieldNormMapLevelOfMapsFiltrationLevels is (fieldNormMapLevelOfMapsFiltrationLevels K L UK UL targetLevel hN n x : Kˣ) = normUnits K L x.1.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormMapLevelOfMapsFiltrationLevels_apply
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    (x : UL.principalUnitSubgroup n) :
    (fieldNormMapLevelOfMapsFiltrationLevels K L UK UL targetLevel hN n x :
        Kˣ) =
      normUnits K L x.1
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap

The field norm descended to quotients by compatible principal-unit filtration levels.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormFiltrationQuotientMap
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    Lˣ ⧸ UL.principalUnitSubgroup n →*
      Kˣ ⧸ UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_apply_mk

The defining evaluation formula for fieldNormFiltrationQuotientMap is fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk x) = QuotientGroup.mk (normUnits K L x).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_apply_mk
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] (x : Lˣ) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk x) =
      QuotientGroup.mk (normUnits K L x)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_apply_mk'

Establishes the identity fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) = QuotientGroup.mk' (UK.principalUnitSubgroup (targetLevel n)) (normUnits K L x).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_apply_mk'
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] (x : Lˣ) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) =
      QuotientGroup.mk' (UK.principalUnitSubgroup (targetLevel n))
        (normUnits K L x)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_mk_eq_one_iff

Characterizes fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) = 1 by the equivalent condition normUnits K L x ∈ UK.principalUnitSubgroup (targetLevel n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_mk_eq_one_iff
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] (x : Lˣ) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) = 1 ↔
      normUnits K L x ∈
        UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_mk_eq_iff_div_mem

Characterizes fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) = fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) y) by the equivalent condition normUnits K L (x / y) ∈ UK.principalUnitSubgroup (targetLevel n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_mk_eq_iff_div_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] (x y : Lˣ) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) =
      fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) y) ↔
      normUnits K L (x / y) ∈
        UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_mk_eq_iff_inv_mul_mem

Characterizes fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) = fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n (QuotientGroup.mk' (UL.principalUnitSubgroup n) y) by the equivalent condition normUnits K L (y⁻¹ * x) ∈ UK.principalUnitSubgroup (targetLevel n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_mk_eq_iff_inv_mul_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] (x y : Lˣ) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) x) =
      fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n
        (QuotientGroup.mk' (UL.principalUnitSubgroup n) y) ↔
      normUnits K L (y⁻¹ * x) ∈
        UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_surjective_iff_exists_div_mem

Characterizes Function.Surjective (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n) by the equivalent condition ∀ y : Kˣ, ∃ x : Lˣ, normUnits K L x / y ∈ UK.principalUnitSubgroup (targetLevel n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_surjective_iff_exists_div_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    Function.Surjective
      (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n) ↔
      ∀ y : Kˣ, ∃ x : Lˣ,
        normUnits K L x / y ∈
          UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_surjective_of_exists_div_mem

The specified map is surjective: Function.Surjective (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_surjective_of_exists_div_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (hLift : ∀ y : Kˣ, ∃ x : Lˣ,
      normUnits K L x / y ∈
        UK.principalUnitSubgroup (targetLevel n)) :
    Function.Surjective
      (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationPreimageSubgroup

The preimage of a target principal-unit filtration subgroup under the field norm.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormFiltrationPreimageSubgroup
    (UK : AntitoneSubgroupFiltration Kˣ) (targetLevel : ℕ → ℕ) (n : ℕ) :
    Subgroup Lˣ
LocalFieldTheory.DiscreteValuationField.mem_fieldNormFiltrationPreimageSubgroup_iff

Characterizes x ∈ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n by the equivalent condition normUnits K L x ∈ UK.principalUnitSubgroup (targetLevel n).

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem mem_fieldNormFiltrationPreimageSubgroup_iff
    (UK : AntitoneSubgroupFiltration Kˣ) (targetLevel : ℕ → ℕ) (n : ℕ)
    (x : Lˣ) :
    x ∈ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n ↔
      normUnits K L x ∈
        UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.principalUnitSubgroup_le_fieldNormFiltrationPreimageSubgroup

Proves the bound UL.principalUnitSubgroup n ≤ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem principalUnitSubgroup_le_fieldNormFiltrationPreimageSubgroup
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ) :
    UL.principalUnitSubgroup n ≤
      fieldNormFiltrationPreimageSubgroup K L UK targetLevel n
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationPreimageSubgroup_normal

The subgroup appearing in (fieldNormFiltrationPreimageSubgroup K L UK targetLevel n).Normal is normal.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
instance fieldNormFiltrationPreimageSubgroup_normal
    (UK : AntitoneSubgroupFiltration Kˣ) (targetLevel : ℕ → ℕ) (n : ℕ)
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    (fieldNormFiltrationPreimageSubgroup K L UK targetLevel n).Normal
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationPreimageClassInQuotient

The class of the field-norm preimage of the target filtration subgroup inside the source filtration quotient.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormFiltrationPreimageClassInQuotient
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal] :
    Subgroup (Lˣ ⧸ UL.principalUnitSubgroup n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationPreimageClassInQuotient_normal

The subgroup appearing in (fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n).Normal is normal.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
instance fieldNormFiltrationPreimageClassInQuotient_normal
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    (fieldNormFiltrationPreimageClassInQuotient
      K L UK UL targetLevel n).Normal
LocalFieldTheory.DiscreteValuationField.mem_fieldNormFiltrationPreimageClassInQuotient_iff

Characterizes q ∈ fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n by the equivalent condition ∃ x : Lˣ, x ∈ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n ∧ QuotientGroup.mk' (UL.principalUnitSubgroup n) x = q.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem mem_fieldNormFiltrationPreimageClassInQuotient_iff
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    q ∈ fieldNormFiltrationPreimageClassInQuotient
        K L UK UL targetLevel n ↔
      ∃ x : Lˣ,
        x ∈ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n ∧
        QuotientGroup.mk' (UL.principalUnitSubgroup n) x = q
LocalFieldTheory.DiscreteValuationField.mem_fieldNormFiltrationPreimageClassInQuotient_iff_exists_norm_mem

Characterizes q ∈ fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n by the equivalent condition ∃ x : Lˣ, normUnits K L x ∈ UK.principalUnitSubgroup (targetLevel n) ∧ QuotientGroup.mk' (UL.principalUnitSubgroup n) x = q.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem mem_fieldNormFiltrationPreimageClassInQuotient_iff_exists_norm_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    q ∈ fieldNormFiltrationPreimageClassInQuotient
        K L UK UL targetLevel n ↔
      ∃ x : Lˣ,
        normUnits K L x ∈
          UK.principalUnitSubgroup (targetLevel n) ∧
        QuotientGroup.mk' (UL.principalUnitSubgroup n) x = q
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationPreimageClassInQuotient_mk_mem

Establishes the membership statement QuotientGroup.mk' (UL.principalUnitSubgroup n) x ∈ fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationPreimageClassInQuotient_mk_mem
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ) {n : ℕ}
    [(UL.principalUnitSubgroup n).Normal] {x : Lˣ}
    (hx : x ∈ fieldNormFiltrationPreimageSubgroup K L UK targetLevel n) :
    QuotientGroup.mk' (UL.principalUnitSubgroup n) x ∈
      fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_ker_eq_preimageClass

The kernel of the concrete field-norm filtration quotient map is the class of the norm-preimage of the target filtration subgroup.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_ker_eq_preimageClass
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n).ker =
      fieldNormFiltrationPreimageClassInQuotient
        K L UK UL targetLevel n
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientMap_eq_one_iff_mem_preimageClass

Characterizes fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q = 1 by the equivalent condition q ∈ fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientMap_eq_one_iff_mem_preimageClass
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q = 1 ↔
      q ∈ fieldNormFiltrationPreimageClassInQuotient
        K L UK UL targetLevel n
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientModuloPreimageClassEquivRange

First-isomorphism form of the concrete field-norm filtration quotient map, with codomain the actual range when no surjectivity hypothesis is available.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormFiltrationQuotientModuloPreimageClassEquivRange
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal] :
    (Lˣ ⧸ UL.principalUnitSubgroup n) ⧸
        fieldNormFiltrationPreimageClassInQuotient
          K L UK UL targetLevel n ≃*
      (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n).range
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientModuloPreimageClassEquivRange_mk

Establishes the identity fieldNormFiltrationQuotientModuloPreimageClassEquivRange K L UK UL targetLevel hN n (QuotientGroup.mk' (fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n) q) = (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n).rangeRestrict q.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientModuloPreimageClassEquivRange_mk
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    fieldNormFiltrationQuotientModuloPreimageClassEquivRange
        K L UK UL targetLevel hN n
        (QuotientGroup.mk'
          (fieldNormFiltrationPreimageClassInQuotient
            K L UK UL targetLevel n) q) =
      (fieldNormFiltrationQuotientMap
        K L UK UL targetLevel hN n).rangeRestrict q
LocalFieldTheory.DiscreteValuationField.coe_fieldNormFiltrationQuotientModuloPreimageClassEquivRange_mk

Establishes the identity ((fieldNormFiltrationQuotientModuloPreimageClassEquivRange K L UK UL targetLevel hN n (QuotientGroup.mk' (fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n) q) : (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n).range) : Kˣ ⧸ UK.principalUnitSubgroup (targetLevel n)) = fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem coe_fieldNormFiltrationQuotientModuloPreimageClassEquivRange_mk
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    ((fieldNormFiltrationQuotientModuloPreimageClassEquivRange
        K L UK UL targetLevel hN n
        (QuotientGroup.mk'
          (fieldNormFiltrationPreimageClassInQuotient
            K L UK UL targetLevel n) q) :
      (fieldNormFiltrationQuotientMap
        K L UK UL targetLevel hN n).range) :
        Kˣ ⧸ UK.principalUnitSubgroup (targetLevel n)) =
      fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientModuloPreimageClassEquivTarget

First-isomorphism form of a surjective concrete field-norm filtration quotient map.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
def fieldNormFiltrationQuotientModuloPreimageClassEquivTarget
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (hSurj : Function.Surjective
      (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n)) :
    (Lˣ ⧸ UL.principalUnitSubgroup n) ⧸
        fieldNormFiltrationPreimageClassInQuotient
          K L UK UL targetLevel n ≃*
      Kˣ ⧸ UK.principalUnitSubgroup (targetLevel n)
LocalFieldTheory.DiscreteValuationField.fieldNormFiltrationQuotientModuloPreimageClassEquivTarget_mk

Establishes the identity fieldNormFiltrationQuotientModuloPreimageClassEquivTarget K L UK UL targetLevel hN n hSurj (QuotientGroup.mk' (fieldNormFiltrationPreimageClassInQuotient K L UK UL targetLevel n) q) = fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q.

Source context 6 commands

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

namespace LocalFieldTheory
noncomputable section
universe u v w
namespace DiscreteValuationField
variable (K : Type u) (L : Type v)
variable [Field K] [Field L] [Algebra K L]
theorem fieldNormFiltrationQuotientModuloPreimageClassEquivTarget_mk
    (UK : AntitoneSubgroupFiltration Kˣ) (UL : AntitoneSubgroupFiltration Lˣ)
    (targetLevel : ℕ → ℕ)
    (hN : fieldNormMapsFiltrationLevels K L UK UL targetLevel) (n : ℕ)
    [(UL.principalUnitSubgroup n).Normal]
    [(UK.principalUnitSubgroup (targetLevel n)).Normal]
    (hSurj : Function.Surjective
      (fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n))
    (q : Lˣ ⧸ UL.principalUnitSubgroup n) :
    fieldNormFiltrationQuotientModuloPreimageClassEquivTarget
        K L UK UL targetLevel hN n hSurj
        (QuotientGroup.mk'
          (fieldNormFiltrationPreimageClassInQuotient
            K L UK UL targetLevel n) q) =
      fieldNormFiltrationQuotientMap K L UK UL targetLevel hN n q