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 ( 𝐴 𝐵 ) = ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 shjshs.1 𝐴S
2 shjshs.2 𝐵S
3 shjval ( ( 𝐴S𝐵S ) → ( 𝐴 𝐵 ) = ( ⊥ ‘ ( ⊥ ‘ ( 𝐴𝐵 ) ) ) )
4 1 2 3 mp2an ( 𝐴 𝐵 ) = ( ⊥ ‘ ( ⊥ ‘ ( 𝐴𝐵 ) ) )
5 1 2 shunssi ( 𝐴𝐵 ) ⊆ ( 𝐴 + 𝐵 )
6 1 shssii 𝐴 ⊆ ℋ
7 2 shssii 𝐵 ⊆ ℋ
8 6 7 unssi ( 𝐴𝐵 ) ⊆ ℋ
9 1 2 shscli ( 𝐴 + 𝐵 ) ∈ S
10 9 shssii ( 𝐴 + 𝐵 ) ⊆ ℋ
11 8 10 occon2i ( ( 𝐴𝐵 ) ⊆ ( 𝐴 + 𝐵 ) → ( ⊥ ‘ ( ⊥ ‘ ( 𝐴𝐵 ) ) ) ⊆ ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ) )
12 5 11 ax-mp ( ⊥ ‘ ( ⊥ ‘ ( 𝐴𝐵 ) ) ) ⊆ ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) )
13 4 12 eqsstri ( 𝐴 𝐵 ) ⊆ ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) )
14 1 2 shsleji ( 𝐴 + 𝐵 ) ⊆ ( 𝐴 𝐵 )
15 1 2 shjcli ( 𝐴 𝐵 ) ∈ C
16 15 chssii ( 𝐴 𝐵 ) ⊆ ℋ
17 occon ( ( ( 𝐴 + 𝐵 ) ⊆ ℋ ∧ ( 𝐴 𝐵 ) ⊆ ℋ ) → ( ( 𝐴 + 𝐵 ) ⊆ ( 𝐴 𝐵 ) → ( ⊥ ‘ ( 𝐴 𝐵 ) ) ⊆ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ) )
18 10 16 17 mp2an ( ( 𝐴 + 𝐵 ) ⊆ ( 𝐴 𝐵 ) → ( ⊥ ‘ ( 𝐴 𝐵 ) ) ⊆ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) )
19 14 18 ax-mp ( ⊥ ‘ ( 𝐴 𝐵 ) ) ⊆ ( ⊥ ‘ ( 𝐴 + 𝐵 ) )
20 occl ( ( 𝐴 + 𝐵 ) ⊆ ℋ → ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ∈ C )
21 10 20 ax-mp ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ∈ C
22 15 21 chsscon1i ( ( ⊥ ‘ ( 𝐴 𝐵 ) ) ⊆ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ↔ ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ) ⊆ ( 𝐴 𝐵 ) )
23 19 22 mpbi ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) ) ⊆ ( 𝐴 𝐵 )
24 13 23 eqssi ( 𝐴 𝐵 ) = ( ⊥ ‘ ( ⊥ ‘ ( 𝐴 + 𝐵 ) ) )