English
If two mixed-space elements have the same norm at complex places, then they have the same norm at all places.
Русский
Если у двух элементов смешанного пространства одна и та же норма на комплексных местах, то на всех местах нормы равны.
LaTeX
$$$$\text{If } \operatorname{normAtComplexPlaces}(x) = \operatorname{normAtComplexPlaces}(y) \text{ then } \operatorname{normAtAllPlaces}(x) = \operatorname{normAtAllPlaces}(y).$$$$
Lean4
theorem normAtAllPlaces_eq_of_normAtComplexPlaces_eq {x y : mixedSpace K}
(h : normAtComplexPlaces x = normAtComplexPlaces y) : normAtAllPlaces x = normAtAllPlaces y :=
by
ext w
obtain hw | hw := isReal_or_isComplex w
·
simpa [normAtAllPlaces_apply, normAtPlace_apply_of_isReal hw, normAtComplexPlaces_apply_isReal ⟨w, hw⟩] using
congr_arg (|·|) (congr_fun h w)
·
simpa [normAtAllPlaces_apply, normAtPlace_apply_of_isComplex hw, normAtComplexPlaces_apply_isComplex ⟨w, hw⟩] using
congr_fun h w