Metamath Proof Explorer


Theorem pexmidN

Description: Excluded middle law for closed projective subspaces, which can be shown to be equivalent to (and derivable from) the orthomodular law poml4N . Lemma 3.3(2) in Holland95 p. 215, which we prove as a special case of osumclN . (Contributed by NM, 25-Mar-2012) (New usage is discouraged.)

Ref Expression
Hypotheses pexmid.a 𝐴 = ( Atoms ‘ 𝐾 )
pexmid.p + = ( +𝑃𝐾 )
pexmid.o = ( ⊥𝑃𝐾 )
Assertion pexmidN ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 + ( 𝑋 ) ) = 𝐴 )

Proof

Step Hyp Ref Expression
1 pexmid.a 𝐴 = ( Atoms ‘ 𝐾 )
2 pexmid.p + = ( +𝑃𝐾 )
3 pexmid.o = ( ⊥𝑃𝐾 )
4 simpll ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → 𝐾 ∈ HL )
5 simplr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → 𝑋𝐴 )
6 1 3 polssatN ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) → ( 𝑋 ) ⊆ 𝐴 )
7 6 adantr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 ) ⊆ 𝐴 )
8 1 2 3 poldmj1N ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ∧ ( 𝑋 ) ⊆ 𝐴 ) → ( ‘ ( 𝑋 + ( 𝑋 ) ) ) = ( ( 𝑋 ) ∩ ( ‘ ( 𝑋 ) ) ) )
9 4 5 7 8 syl3anc ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ( 𝑋 + ( 𝑋 ) ) ) = ( ( 𝑋 ) ∩ ( ‘ ( 𝑋 ) ) ) )
10 1 3 pnonsingN ( ( 𝐾 ∈ HL ∧ ( 𝑋 ) ⊆ 𝐴 ) → ( ( 𝑋 ) ∩ ( ‘ ( 𝑋 ) ) ) = ∅ )
11 4 7 10 syl2anc ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ( 𝑋 ) ∩ ( ‘ ( 𝑋 ) ) ) = ∅ )
12 9 11 eqtrd ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ( 𝑋 + ( 𝑋 ) ) ) = ∅ )
13 12 fveq2d ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ( ‘ ( 𝑋 + ( 𝑋 ) ) ) ) = ( ‘ ∅ ) )
14 simpr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ( 𝑋 ) ) = 𝑋 )
15 eqid ( PSubCl ‘ 𝐾 ) = ( PSubCl ‘ 𝐾 )
16 1 3 15 ispsubclN ( 𝐾 ∈ HL → ( 𝑋 ∈ ( PSubCl ‘ 𝐾 ) ↔ ( 𝑋𝐴 ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) ) )
17 16 ad2antrr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 ∈ ( PSubCl ‘ 𝐾 ) ↔ ( 𝑋𝐴 ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) ) )
18 5 14 17 mpbir2and ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → 𝑋 ∈ ( PSubCl ‘ 𝐾 ) )
19 1 3 15 polsubclN ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) → ( 𝑋 ) ∈ ( PSubCl ‘ 𝐾 ) )
20 19 adantr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 ) ∈ ( PSubCl ‘ 𝐾 ) )
21 1 3 2polssN ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) → 𝑋 ⊆ ( ‘ ( 𝑋 ) ) )
22 21 adantr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → 𝑋 ⊆ ( ‘ ( 𝑋 ) ) )
23 2 3 15 osumclN ( ( ( 𝐾 ∈ HL ∧ 𝑋 ∈ ( PSubCl ‘ 𝐾 ) ∧ ( 𝑋 ) ∈ ( PSubCl ‘ 𝐾 ) ) ∧ 𝑋 ⊆ ( ‘ ( 𝑋 ) ) ) → ( 𝑋 + ( 𝑋 ) ) ∈ ( PSubCl ‘ 𝐾 ) )
24 4 18 20 22 23 syl31anc ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 + ( 𝑋 ) ) ∈ ( PSubCl ‘ 𝐾 ) )
25 3 15 psubcli2N ( ( 𝐾 ∈ HL ∧ ( 𝑋 + ( 𝑋 ) ) ∈ ( PSubCl ‘ 𝐾 ) ) → ( ‘ ( ‘ ( 𝑋 + ( 𝑋 ) ) ) ) = ( 𝑋 + ( 𝑋 ) ) )
26 4 24 25 syl2anc ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ( ‘ ( 𝑋 + ( 𝑋 ) ) ) ) = ( 𝑋 + ( 𝑋 ) ) )
27 1 3 pol0N ( 𝐾 ∈ HL → ( ‘ ∅ ) = 𝐴 )
28 27 ad2antrr ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( ‘ ∅ ) = 𝐴 )
29 13 26 28 3eqtr3d ( ( ( 𝐾 ∈ HL ∧ 𝑋𝐴 ) ∧ ( ‘ ( 𝑋 ) ) = 𝑋 ) → ( 𝑋 + ( 𝑋 ) ) = 𝐴 )