theorem
GaloisRepresentation.IsHardlyRamified.mod_three
{k : Type u}
[Fintype k]
[Field k]
[Algebra ℤ_[3] k]
[TopologicalSpace k]
[DiscreteTopology k]
(V : Type u_1)
[AddCommGroup V]
[Module k V]
[Module.Finite k V]
[Module.Free k V]
(hV : Module.rank k V = 2)
{ρ : GaloisRep ℚ k V}
(hρ : IsHardlyRamified ⋯ hV ρ)
:
∃ (π : V →ₗ[k] k) (_ : Function.Surjective ⇑π), ∀ (g : Field.absoluteGaloisGroup ℚ) (v : V), π ((ρ g) v) = π v
A mod 3 hardly ramified representation is an extension of trivial by cyclo