English
The map from real-space K to mixed-space K is injective: if mixedSpaceOfRealSpace x = mixedSpaceOfRealSpace y then x = y.
Русский
Отображение real-space в смешанное пространство инъективно: равенство изображений значит равенство исходных объектов.
LaTeX
$$$\forall x,y:\, realSpace(K),\ (mixedSpaceOfRealSpace\;x = mixedSpaceOfRealSpace\;y) \Rightarrow x = y.$$$
Lean4
theorem injective_mixedSpaceOfRealSpace : Function.Injective (mixedSpaceOfRealSpace : realSpace K → mixedSpace K) :=
by
refine (injective_iff_map_eq_zero mixedSpaceOfRealSpace).mpr fun _ h ↦ ?_
rw [mixedSpaceOfRealSpace_apply, Prod.mk_eq_zero, funext_iff, funext_iff] at h
ext w
obtain hw | hw := isReal_or_isComplex w
· exact h.1 ⟨w, hw⟩
· exact Complex.ofReal_inj.mp <| h.2 ⟨w, hw⟩