set g = FormFunctional (f,(f *'));
thus
FormFunctional (f,(f *')) is diagReR+0valued
( FormFunctional (f,(f *')) is hermitan & FormFunctional (f,(f *')) is diagRvalued )proof
let v be
Vector of
V;
HERMITAN:def 7 0 <= Re ((FormFunctional (f,(f *'))) . (v,v))
(
(FormFunctional (f,(f *'))) . (
v,
v)
= (|.(f . v).| ^2) + (0 * <i>) &
(FormFunctional (f,(f *'))) . (
v,
v)
= (Re ((FormFunctional (f,(f *'))) . (v,v))) + ((Im ((FormFunctional (f,(f *'))) . (v,v))) * <i>) )
by Th28, COMPLEX1:13;
then
Re ((FormFunctional (f,(f *'))) . (v,v)) = |.(f . v).| ^2
by COMPLEX1:77;
hence
0 <= Re ((FormFunctional (f,(f *'))) . (v,v))
by XREAL_1:63;
verum
end;
thus
FormFunctional (f,(f *')) is hermitan
FormFunctional (f,(f *')) is diagRvalued
let v be Vector of V; HERMITAN:def 6 Im ((FormFunctional (f,(f *'))) . (v,v)) = 0
( (FormFunctional (f,(f *'))) . (v,v) = [**(|.(f . v).| ^2),0**] & (FormFunctional (f,(f *'))) . (v,v) = (Re ((FormFunctional (f,(f *'))) . (v,v))) + ((Im ((FormFunctional (f,(f *'))) . (v,v))) * <i>) )
by Th28, COMPLEX1:13;
hence
Im ((FormFunctional (f,(f *'))) . (v,v)) = 0
by COMPLEX1:77; verum