Metamath Proof Explorer


Definition df-aj

Description: Define the adjoint of an operator (if it exists). The domain of U adj W is the set of all operators from U to W that have an adjoint. Definition 3.9-1 of Kreyszig p. 196, although we don't require that U and W be Hilbert spaces nor that the operators be linear. Although we define it for any normed vector space for convenience, the definition is meaningful only for inner product spaces. (Contributed by NM, 25-Jan-2008) (New usage is discouraged.)

Ref Expression
Assertion df-aj adj=uNrmCVec,wNrmCVects|t:BaseSetuBaseSetws:BaseSetwBaseSetuxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy

Detailed syntax breakdown

Step Hyp Ref Expression
0 caj classadj
1 vu setvaru
2 cnv classNrmCVec
3 vw setvarw
4 vt setvart
5 vs setvars
6 4 cv setvart
7 cba classBaseSet
8 1 cv setvaru
9 8 7 cfv classBaseSetu
10 3 cv setvarw
11 10 7 cfv classBaseSetw
12 9 11 6 wf wfft:BaseSetuBaseSetw
13 5 cv setvars
14 11 9 13 wf wffs:BaseSetwBaseSetu
15 vx setvarx
16 vy setvary
17 15 cv setvarx
18 17 6 cfv classtx
19 cdip class𝑖OLD
20 10 19 cfv class𝑖OLDw
21 16 cv setvary
22 18 21 20 co classtx𝑖OLDwy
23 8 19 cfv class𝑖OLDu
24 21 13 cfv classsy
25 17 24 23 co classx𝑖OLDusy
26 22 25 wceq wfftx𝑖OLDwy=x𝑖OLDusy
27 26 16 11 wral wffyBaseSetwtx𝑖OLDwy=x𝑖OLDusy
28 27 15 9 wral wffxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy
29 12 14 28 w3a wfft:BaseSetuBaseSetws:BaseSetwBaseSetuxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy
30 29 4 5 copab classts|t:BaseSetuBaseSetws:BaseSetwBaseSetuxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy
31 1 3 2 2 30 cmpo classuNrmCVec,wNrmCVects|t:BaseSetuBaseSetws:BaseSetwBaseSetuxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy
32 0 31 wceq wffadj=uNrmCVec,wNrmCVects|t:BaseSetuBaseSetws:BaseSetwBaseSetuxBaseSetuyBaseSetwtx𝑖OLDwy=x𝑖OLDusy