English
There is a homeomorphism between the product X ⨯ Y in TopCat and the set-theoretic product TopCat.of (X × Y) with the product topology.
Русский
Существует топологическое гомеоморфизм между произведением X ⨯ Y в TopCat и множестенным произведением TopCat.of (X × Y) с произведённой топологией.
LaTeX
$$$\\mathrm{prodIsoProd}(X,Y) : X \\boxtimes Y \\cong \\mathrm{TopCat.of}(X \\times Y)$$$
Lean4
/-- The homeomorphism between `X ⨯ Y` and the set-theoretic product of `X` and `Y`,
equipped with the product topology.
-/
def prodIsoProd (X Y : TopCat.{u}) : X ⨯ Y ≅ TopCat.of (X × Y) :=
(limit.isLimit _).conePointUniqueUpToIso (prodBinaryFanIsLimit X Y)