/- Copyright (c) 2024 Joseph Tooby-Smith. All rights reserved. Released under Apache 2.0 license. Authors: Joseph Tooby-Smith -/ import HepLean.AnomalyCancellation.PureU1.Permutations /-! # The Pure U(1) case with 1 fermion We show that in this case the charge must be zero. -/ universe v u open Nat open Finset namespace PureU1 variable {n : ℕ} namespace One theorem solEqZero (S : (PureU1 1).LinSols) : S = 0 := by apply ACCSystemLinear.LinSols.ext have hLin := pureU1_linear S simp at hLin funext i simp at i rw [show i = (0 : Fin 1) by omega] exact hLin end One end PureU1