Metamath Proof Explorer


Theorem shjshsi

Description: Hilbert lattice join equals the double orthocomplement of subspace sum. (Contributed by NM, 27-Nov-2004) (New usage is discouraged.)

Ref Expression
Hypotheses shjshs.1 AS
shjshs.2 BS
Assertion shjshsi AB=A+B

Proof

Step Hyp Ref Expression
1 shjshs.1 AS
2 shjshs.2 BS
3 shjval ASBSAB=AB
4 1 2 3 mp2an AB=AB
5 1 2 shunssi ABA+B
6 1 shssii A
7 2 shssii B
8 6 7 unssi AB
9 1 2 shscli A+BS
10 9 shssii A+B
11 8 10 occon2i ABA+BABA+B
12 5 11 ax-mp ABA+B
13 4 12 eqsstri ABA+B
14 1 2 shsleji A+BAB
15 1 2 shjcli ABC
16 15 chssii AB
17 occon A+BABA+BABABA+B
18 10 16 17 mp2an A+BABABA+B
19 14 18 ax-mp ABA+B
20 occl A+BA+BC
21 10 20 ax-mp A+BC
22 15 21 chsscon1i ABA+BA+BAB
23 19 22 mpbi A+BAB
24 13 23 eqssi AB=A+B