English
The lattice of intermediate fields is compactly generated by the compact elements F⟮x⟯ and finite joins adjoin F S.
Русский
Решетка промежуточных полей компактно порождается компактными элементами вида F⟮x⟯ и конечными соединениями adjoin.
LaTeX
$$IsCompactlyGenerated (IntermediateField F E)$$
Lean4
/-- The lattice of intermediate fields is compactly generated. -/
instance : IsCompactlyGenerated (IntermediateField F E) :=
⟨fun s =>
⟨(fun x => F⟮x⟯) '' s,
⟨by rintro t ⟨x, _, rfl⟩; exact adjoin_simple_isCompactElement x,
sSup_image.trans <|
(biSup_adjoin_simple _).trans <| le_antisymm (adjoin_le_iff.mpr le_rfl) <| subset_adjoin F (s : Set E)⟩⟩⟩