Module

HilbertProductFormulaAlgEquiv.lean

Nyll.ClassFieldTheory.GlobalClassFieldTheory.Reciprocity.HilbertProductFormulaAlgEquiv
1 declaration indexed from sourceView source ↗

Transport of the Hilbert product formula

The product formula is invariant under a number-field equivalence. The finite product is reindexed by the induced equivalence of finite places, and the ordinary infinite product by the equivalence of infinite places.

Declarations

ClassFieldTheory.globalHilbertPairingFamilyCongr_productFormula

The Hilbert product formula survives transport of the local-pairing family across a number-field equivalence.

Source context 5 commands

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

open scoped BigOperators NumberField
open NumberField IsDedekindDomain
noncomputable section
namespace ClassFieldTheory
universe u v
theorem globalHilbertPairingFamilyCongr_productFormula
    {F : Type u} {G : Type v}
    [Field F] [NumberField F] [Field G] [NumberField G]
    (e : F ≃ₐ[ℚ] G) (n : ℕ+)
    (hmuF : (primitiveRoots (n : ℕ) F).Nonempty)
    (hmuG : (primitiveRoots (n : ℕ) G).Nonempty)
    (BF : GlobalHilbertPairingFamily F n)
    (hBF : ∀ a b : Fˣ,
      (∏ v : InfinitePlace F,
          globalInfinitePlaceHilbertSymbol F n v a b) *
        ∏ᶠ v : HeightOneSpectrum (𝓞 F),
          GlobalHilbertPairingFamily.finiteFactor F BF hmuF v a b = 1) :
    ∀ a b : Gˣ,
      (∏ W : InfinitePlace G,
          globalInfinitePlaceHilbertSymbol G n W a b) *
        ∏ᶠ W : HeightOneSpectrum (𝓞 G),
          GlobalHilbertPairingFamily.finiteFactor G
            (globalHilbertPairingFamilyCongr e n hmuF BF) hmuG W a b = 1