English
The map induced by embedding α into β via rationals is defined by taking x to the supremum of the cut-map images below x.
Русский
Отображение, индуцируемое вложением из поля α в β, задаётся как верхняя граница множества rationals меньше x через cutMap.
LaTeX
$$$\\mathrm{inducedMap}(x) = \\mathrm{sSup} (\\mathrm{cutMap}\\,\\beta\\ x)$$$
Lean4
/-- The induced order-preserving function from a linear ordered field to a conditionally complete
linear ordered field, defined by taking the Sup in the codomain of all the rationals less than the
input. -/
def inducedMap (x : α) : β :=
sSup <| cutMap β x