Module

DirectThetaIteration.lean

Nyll.ClassFieldTheory.LubinTate.EqualCharacteristic.CompletedLevel.DirectThetaIteration
10 declarations indexed from sourceView source ↗

The completed theta-intertwining theorem: iterating the direct second theta identity

For the direct orientation T → uT, this file applies coefficient Frobenius repeatedly to the formal identity theta^φ ∘ e_T = e_(uT) ∘ theta.

Declarations

LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate

The i-fold arithmetic-Frobenius twist of the direct theta series.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
def equalCharacteristicDirectThetaSeriesFrobeniusIterate
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) :
    ℕ → ((AlgebraicClosure k)⟦X⟧)⟦X⟧
  | 0 => equalCharacteristicDirectThetaSeries u
  | i + 1 => PowerSeries.map (equalCharacteristicPowerSeriesFrobenius k)
      (equalCharacteristicDirectThetaSeriesFrobeniusIterate u i)
LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate_zero

States the theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_zero.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_zero
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) :
    equalCharacteristicDirectThetaSeriesFrobeniusIterate u 0 =
      equalCharacteristicDirectThetaSeries u
LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate_succ

States the theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_succ.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_succ
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) (i : ℕ) :
    equalCharacteristicDirectThetaSeriesFrobeniusIterate u (i + 1) =
      PowerSeries.map (equalCharacteristicPowerSeriesFrobenius k)
        (equalCharacteristicDirectThetaSeriesFrobeniusIterate u i)
LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate_constantCoeff

States the theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_constantCoeff.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_constantCoeff
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) (i : ℕ) :
    PowerSeries.constantCoeff
      (equalCharacteristicDirectThetaSeriesFrobeniusIterate u i) = 0
LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate_hasSubst

States the theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_hasSubst.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_hasSubst
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) (i : ℕ) :
    PowerSeries.HasSubst
      (equalCharacteristicDirectThetaSeriesFrobeniusIterate u i)
LubinTate.EqualCharacteristic.equalCharacteristicDirectCompletedTargetUniformizer_frobenius
Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectCompletedTargetUniformizer_frobenius
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) :
    equalCharacteristicPowerSeriesFrobenius k
        (equalCharacteristicDirectCompletedTargetUniformizer u) =
      equalCharacteristicDirectCompletedTargetUniformizer u
LubinTate.EqualCharacteristic.equalCharacteristicDirectCompletedLubinTateSeries_map_frobenius
Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectCompletedLubinTateSeries_map_frobenius
    {k : Type*} [Field k] [Finite k]
    (pi : (AlgebraicClosure k)⟦X⟧) :
    PowerSeries.map (equalCharacteristicPowerSeriesFrobenius k)
        (equalCharacteristicCompletedLubinTateSeries (k := k) pi) =
      equalCharacteristicCompletedLubinTateSeries (k := k)
        (equalCharacteristicPowerSeriesFrobenius k pi)
LubinTate.EqualCharacteristic.equalCharacteristicDirectSourceLubinTateSeries_frobenius
Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectSourceLubinTateSeries_frobenius
    {k : Type*} [Field k] [Finite k] :
    PowerSeries.map (equalCharacteristicPowerSeriesFrobenius k)
        (equalCharacteristicCompletedLubinTateSeries (k := k)
          (PowerSeries.X : (AlgebraicClosure k)⟦X⟧)) =
      equalCharacteristicCompletedLubinTateSeries (k := k) PowerSeries.X
LubinTate.EqualCharacteristic.equalCharacteristicDirectTargetLubinTateSeries_frobenius
Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectTargetLubinTateSeries_frobenius
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) :
    PowerSeries.map (equalCharacteristicPowerSeriesFrobenius k)
        (equalCharacteristicCompletedLubinTateSeries (k := k)
          (equalCharacteristicDirectCompletedTargetUniformizer u)) =
      equalCharacteristicCompletedLubinTateSeries (k := k)
        (equalCharacteristicDirectCompletedTargetUniformizer u)
LubinTate.EqualCharacteristic.equalCharacteristicDirectThetaSeriesFrobeniusIterate_intertwines

Every direct Frobenius twist intertwines the next source and target Lubin--Tate steps.

Source context 4 commands

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

noncomputable section
open scoped PowerSeries
namespace LubinTate
namespace EqualCharacteristic
theorem equalCharacteristicDirectThetaSeriesFrobeniusIterate_intertwines
    {k : Type*} [Field k] [Finite k] (u : k⟦X⟧ˣ) (i : ℕ) :
    PowerSeries.subst
        (equalCharacteristicCompletedLubinTateSeries (k := k)
          (PowerSeries.X : (AlgebraicClosure k)⟦X⟧))
        (equalCharacteristicDirectThetaSeriesFrobeniusIterate u (i + 1)) =
      PowerSeries.subst
        (equalCharacteristicDirectThetaSeriesFrobeniusIterate u i)
        (equalCharacteristicCompletedLubinTateSeries (k := k)
          (equalCharacteristicDirectCompletedTargetUniformizer u))