English
For a subobject P of op A, there exists q with S.map (projectQuotient P).arrow.unop ≫ q = A.hom.
Русский
Для подобъекта P над op A существует q такой, что S.map (projectQuotient P).arrow.unop ≫ q = A.hom.
LaTeX
$$$\\forall P : \\mathrm{Subobject}(op A),\\; \\exists q, S.map (projectQuotient P).arrow.unop \\\\circ q = A.hom.$$$
Lean4
/-- A quotient of the underlying object of a costructured arrow can be lifted to a quotient of
the costructured arrow, provided that there is a morphism making the quotient into a
costructured arrow. -/
@[simp]
def liftQuotient {A : CostructuredArrow S T} (P : Subobject (op A.left)) {q} (hq : S.map P.arrow.unop ≫ q = A.hom) :
Subobject (op A) :=
Subobject.mk (homMk P.arrow.unop hq : A ⟶ mk q).op