proposition: Lemma eq_galP E (f g : 'AEnd(L)) : (f @: E <= E)%VS -> (g @: E <= E)%VS -> reflect {in E, f =1 g} (gal E f == gal E g).
proof: Proof. move=> EfE EgE. by apply: (iffP gal_eqP) => Dfg a Ea; have:= Dfg a Ea; rewrite !{1}galK. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq div) mathcomp(choice fintype tuple finfun bigop ssralg poly) mathcomp(polydiv finset fingroup morphism quotient perm) mathcomp(action zmodp cyclic matrix mxalgebra vector) mathcomp(falgebra fieldext separable)