Metamath Proof Explorer


Theorem eigorth

Description: A necessary and sufficient condition (that holds when T is a Hermitian operator) for two eigenvectors A and B to be orthogonal. Generalization of Equation 1.31 of Hughes p. 49. (Contributed by NM, 23-Mar-2006) (New usage is discouraged.)

Ref Expression
Assertion eigorth A B C D T A = C A T B = D B C D A ih T B = T A ih B A ih B = 0

Proof

Step Hyp Ref Expression
1 fveq2 A = if A A 0 T A = T if A A 0
2 oveq2 A = if A A 0 C A = C if A A 0
3 1 2 eqeq12d A = if A A 0 T A = C A T if A A 0 = C if A A 0
4 3 anbi1d A = if A A 0 T A = C A T B = D B T if A A 0 = C if A A 0 T B = D B
5 4 anbi1d A = if A A 0 T A = C A T B = D B C D T if A A 0 = C if A A 0 T B = D B C D
6 oveq1 A = if A A 0 A ih T B = if A A 0 ih T B
7 1 oveq1d A = if A A 0 T A ih B = T if A A 0 ih B
8 6 7 eqeq12d A = if A A 0 A ih T B = T A ih B if A A 0 ih T B = T if A A 0 ih B
9 oveq1 A = if A A 0 A ih B = if A A 0 ih B
10 9 eqeq1d A = if A A 0 A ih B = 0 if A A 0 ih B = 0
11 8 10 bibi12d A = if A A 0 A ih T B = T A ih B A ih B = 0 if A A 0 ih T B = T if A A 0 ih B if A A 0 ih B = 0
12 5 11 imbi12d A = if A A 0 T A = C A T B = D B C D A ih T B = T A ih B A ih B = 0 T if A A 0 = C if A A 0 T B = D B C D if A A 0 ih T B = T if A A 0 ih B if A A 0 ih B = 0
13 fveq2 B = if B B 0 T B = T if B B 0
14 oveq2 B = if B B 0 D B = D if B B 0
15 13 14 eqeq12d B = if B B 0 T B = D B T if B B 0 = D if B B 0
16 15 anbi2d B = if B B 0 T if A A 0 = C if A A 0 T B = D B T if A A 0 = C if A A 0 T if B B 0 = D if B B 0
17 16 anbi1d B = if B B 0 T if A A 0 = C if A A 0 T B = D B C D T if A A 0 = C if A A 0 T if B B 0 = D if B B 0 C D
18 13 oveq2d B = if B B 0 if A A 0 ih T B = if A A 0 ih T if B B 0
19 oveq2 B = if B B 0 T if A A 0 ih B = T if A A 0 ih if B B 0
20 18 19 eqeq12d B = if B B 0 if A A 0 ih T B = T if A A 0 ih B if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0
21 oveq2 B = if B B 0 if A A 0 ih B = if A A 0 ih if B B 0
22 21 eqeq1d B = if B B 0 if A A 0 ih B = 0 if A A 0 ih if B B 0 = 0
23 20 22 bibi12d B = if B B 0 if A A 0 ih T B = T if A A 0 ih B if A A 0 ih B = 0 if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0
24 17 23 imbi12d B = if B B 0 T if A A 0 = C if A A 0 T B = D B C D if A A 0 ih T B = T if A A 0 ih B if A A 0 ih B = 0 T if A A 0 = C if A A 0 T if B B 0 = D if B B 0 C D if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0
25 oveq1 C = if C C 0 C if A A 0 = if C C 0 if A A 0
26 25 eqeq2d C = if C C 0 T if A A 0 = C if A A 0 T if A A 0 = if C C 0 if A A 0
27 26 anbi1d C = if C C 0 T if A A 0 = C if A A 0 T if B B 0 = D if B B 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0
28 neeq1 C = if C C 0 C D if C C 0 D
29 27 28 anbi12d C = if C C 0 T if A A 0 = C if A A 0 T if B B 0 = D if B B 0 C D T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0 if C C 0 D
30 29 imbi1d C = if C C 0 T if A A 0 = C if A A 0 T if B B 0 = D if B B 0 C D if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0 if C C 0 D if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0
31 oveq1 D = if D D 0 D if B B 0 = if D D 0 if B B 0
32 31 eqeq2d D = if D D 0 T if B B 0 = D if B B 0 T if B B 0 = if D D 0 if B B 0
33 32 anbi2d D = if D D 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = if D D 0 if B B 0
34 fveq2 D = if D D 0 D = if D D 0
35 34 neeq2d D = if D D 0 if C C 0 D if C C 0 if D D 0
36 33 35 anbi12d D = if D D 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0 if C C 0 D T if A A 0 = if C C 0 if A A 0 T if B B 0 = if D D 0 if B B 0 if C C 0 if D D 0
37 36 imbi1d D = if D D 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = D if B B 0 if C C 0 D if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0 T if A A 0 = if C C 0 if A A 0 T if B B 0 = if D D 0 if B B 0 if C C 0 if D D 0 if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0
38 ifhvhv0 if A A 0
39 ifhvhv0 if B B 0
40 0cn 0
41 40 elimel if C C 0
42 40 elimel if D D 0
43 38 39 41 42 eigorthi T if A A 0 = if C C 0 if A A 0 T if B B 0 = if D D 0 if B B 0 if C C 0 if D D 0 if A A 0 ih T if B B 0 = T if A A 0 ih if B B 0 if A A 0 ih if B B 0 = 0
44 12 24 30 37 43 dedth4h A B C D T A = C A T B = D B C D A ih T B = T A ih B A ih B = 0
45 44 imp A B C D T A = C A T B = D B C D A ih T B = T A ih B A ih B = 0