Module

RationalCyclotomicPrincipalPrimeFactor.lean

Nyll.ClassFieldTheory.GlobalClassFieldTheory.Reciprocity.RationalCyclotomicPrincipalPrimeFactor
2 declarations indexed from sourceView source ↗

The ramified prime factor of a rational cyclotomic principal idele

The level-zero factor is trivial. At every positive level, the finite-place character specification reduces the claim to the ramified chosen-Artin formula proved in RationalCyclotomicFinitePlaceArtin.

Declarations

Source context 3 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace Reciprocity
instance (p : Nat.Primes) : Fact p.1.Prime
GlobalClassFieldTheory.Reciprocity.rationalCyclotomicPrincipalFinitePlaceCharacter_at_prime

The chosen finite-place factor at the ramified prime p is the direct reduction of the rational p-adic unit.

Source context 4 commands

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

noncomputable section
namespace GlobalClassFieldTheory
namespace Reciprocity
local instance (p : Nat.Primes) : Fact p.1.Prime :=
  ⟨p.2⟩
theorem rationalCyclotomicPrincipalFinitePlaceCharacter_at_prime
    (p : Nat.Primes) (k : ℕ) (x : ℚˣ) :
    rationalCyclotomicPrincipalFinitePlaceCharacter p k x p =
      Units.map (PadicInt.toZModPow k).toMonoidHom
        (padicIntUnitOfRat p
          (rationalPrimeUnit x p : ℚ)
          (rationalPrimeUnit x p).ne_zero
          (padicValRat_rationalPrimeUnit x p))