Metamath Proof Explorer


Theorem submrc

Description: In a closure system which is cut off above some level, closures below that level act as normal. (Contributed by Stefan O'Rear, 9-Mar-2015)

Ref Expression
Hypotheses submrc.f 𝐹 = ( mrCls ‘ 𝐶 )
submrc.g 𝐺 = ( mrCls ‘ ( 𝐶 ∩ 𝒫 𝐷 ) )
Assertion submrc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐺𝑈 ) = ( 𝐹𝑈 ) )

Proof

Step Hyp Ref Expression
1 submrc.f 𝐹 = ( mrCls ‘ 𝐶 )
2 submrc.g 𝐺 = ( mrCls ‘ ( 𝐶 ∩ 𝒫 𝐷 ) )
3 submre ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶 ) → ( 𝐶 ∩ 𝒫 𝐷 ) ∈ ( Moore ‘ 𝐷 ) )
4 3 3adant3 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐶 ∩ 𝒫 𝐷 ) ∈ ( Moore ‘ 𝐷 ) )
5 simp1 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝐶 ∈ ( Moore ‘ 𝑋 ) )
6 simp3 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝑈𝐷 )
7 mress ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶 ) → 𝐷𝑋 )
8 7 3adant3 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝐷𝑋 )
9 6 8 sstrd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝑈𝑋 )
10 5 1 9 mrcssidd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝑈 ⊆ ( 𝐹𝑈 ) )
11 1 mrccl ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝑋 ) → ( 𝐹𝑈 ) ∈ 𝐶 )
12 5 9 11 syl2anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐹𝑈 ) ∈ 𝐶 )
13 1 mrcsscl ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈𝐷𝐷𝐶 ) → ( 𝐹𝑈 ) ⊆ 𝐷 )
14 13 3com23 ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐹𝑈 ) ⊆ 𝐷 )
15 fvex ( 𝐹𝑈 ) ∈ V
16 15 elpw ( ( 𝐹𝑈 ) ∈ 𝒫 𝐷 ↔ ( 𝐹𝑈 ) ⊆ 𝐷 )
17 14 16 sylibr ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐹𝑈 ) ∈ 𝒫 𝐷 )
18 12 17 elind ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐹𝑈 ) ∈ ( 𝐶 ∩ 𝒫 𝐷 ) )
19 2 mrcsscl ( ( ( 𝐶 ∩ 𝒫 𝐷 ) ∈ ( Moore ‘ 𝐷 ) ∧ 𝑈 ⊆ ( 𝐹𝑈 ) ∧ ( 𝐹𝑈 ) ∈ ( 𝐶 ∩ 𝒫 𝐷 ) ) → ( 𝐺𝑈 ) ⊆ ( 𝐹𝑈 ) )
20 4 10 18 19 syl3anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐺𝑈 ) ⊆ ( 𝐹𝑈 ) )
21 4 2 6 mrcssidd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → 𝑈 ⊆ ( 𝐺𝑈 ) )
22 2 mrccl ( ( ( 𝐶 ∩ 𝒫 𝐷 ) ∈ ( Moore ‘ 𝐷 ) ∧ 𝑈𝐷 ) → ( 𝐺𝑈 ) ∈ ( 𝐶 ∩ 𝒫 𝐷 ) )
23 4 6 22 syl2anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐺𝑈 ) ∈ ( 𝐶 ∩ 𝒫 𝐷 ) )
24 23 elin1d ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐺𝑈 ) ∈ 𝐶 )
25 1 mrcsscl ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝑈 ⊆ ( 𝐺𝑈 ) ∧ ( 𝐺𝑈 ) ∈ 𝐶 ) → ( 𝐹𝑈 ) ⊆ ( 𝐺𝑈 ) )
26 5 21 24 25 syl3anc ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐹𝑈 ) ⊆ ( 𝐺𝑈 ) )
27 20 26 eqssd ( ( 𝐶 ∈ ( Moore ‘ 𝑋 ) ∧ 𝐷𝐶𝑈𝐷 ) → ( 𝐺𝑈 ) = ( 𝐹𝑈 ) )