Metamath Proof Explorer


Theorem limsucncmpi

Description: The successor of a limit ordinal is not compact. (Contributed by Chen-Pang He, 20-Oct-2015)

Ref Expression
Hypothesis limsucncmpi.1 Lim 𝐴
Assertion limsucncmpi ¬ suc 𝐴 ∈ Comp

Proof

Step Hyp Ref Expression
1 limsucncmpi.1 Lim 𝐴
2 elex ( suc 𝐴 ∈ Top → suc 𝐴 ∈ V )
3 sucexb ( 𝐴 ∈ V ↔ suc 𝐴 ∈ V )
4 2 3 sylibr ( suc 𝐴 ∈ Top → 𝐴 ∈ V )
5 sssucid 𝐴 ⊆ suc 𝐴
6 elpwg ( 𝐴 ∈ V → ( 𝐴 ∈ 𝒫 suc 𝐴𝐴 ⊆ suc 𝐴 ) )
7 5 6 mpbiri ( 𝐴 ∈ V → 𝐴 ∈ 𝒫 suc 𝐴 )
8 limuni ( Lim 𝐴𝐴 = 𝐴 )
9 1 8 ax-mp 𝐴 = 𝐴
10 elin ( 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) ↔ ( 𝑧 ∈ 𝒫 𝐴𝑧 ∈ Fin ) )
11 elpwi ( 𝑧 ∈ 𝒫 𝐴𝑧𝐴 )
12 11 anim1i ( ( 𝑧 ∈ 𝒫 𝐴𝑧 ∈ Fin ) → ( 𝑧𝐴𝑧 ∈ Fin ) )
13 10 12 sylbi ( 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) → ( 𝑧𝐴𝑧 ∈ Fin ) )
14 nlim0 ¬ Lim ∅
15 1 14 2th ( Lim 𝐴 ↔ ¬ Lim ∅ )
16 xor3 ( ¬ ( Lim 𝐴 ↔ Lim ∅ ) ↔ ( Lim 𝐴 ↔ ¬ Lim ∅ ) )
17 15 16 mpbir ¬ ( Lim 𝐴 ↔ Lim ∅ )
18 limeq ( 𝐴 = ∅ → ( Lim 𝐴 ↔ Lim ∅ ) )
19 18 necon3bi ( ¬ ( Lim 𝐴 ↔ Lim ∅ ) → 𝐴 ≠ ∅ )
20 17 19 ax-mp 𝐴 ≠ ∅
21 uni0 ∅ = ∅
22 20 21 neeqtrri 𝐴
23 unieq ( 𝑧 = ∅ → 𝑧 = ∅ )
24 23 neeq2d ( 𝑧 = ∅ → ( 𝐴 𝑧𝐴 ∅ ) )
25 22 24 mpbiri ( 𝑧 = ∅ → 𝐴 𝑧 )
26 25 a1i ( ( 𝑧𝐴𝑧 ∈ Fin ) → ( 𝑧 = ∅ → 𝐴 𝑧 ) )
27 limord ( Lim 𝐴 → Ord 𝐴 )
28 ordsson ( Ord 𝐴𝐴 ⊆ On )
29 1 27 28 mp2b 𝐴 ⊆ On
30 sstr2 ( 𝑧𝐴 → ( 𝐴 ⊆ On → 𝑧 ⊆ On ) )
31 29 30 mpi ( 𝑧𝐴𝑧 ⊆ On )
32 ordunifi ( ( 𝑧 ⊆ On ∧ 𝑧 ∈ Fin ∧ 𝑧 ≠ ∅ ) → 𝑧𝑧 )
33 32 3expia ( ( 𝑧 ⊆ On ∧ 𝑧 ∈ Fin ) → ( 𝑧 ≠ ∅ → 𝑧𝑧 ) )
34 31 33 sylan ( ( 𝑧𝐴𝑧 ∈ Fin ) → ( 𝑧 ≠ ∅ → 𝑧𝑧 ) )
35 ssel ( 𝑧𝐴 → ( 𝑧𝑧 𝑧𝐴 ) )
36 1 27 ax-mp Ord 𝐴
37 nordeq ( ( Ord 𝐴 𝑧𝐴 ) → 𝐴 𝑧 )
38 36 37 mpan ( 𝑧𝐴𝐴 𝑧 )
39 35 38 syl6 ( 𝑧𝐴 → ( 𝑧𝑧𝐴 𝑧 ) )
40 39 adantr ( ( 𝑧𝐴𝑧 ∈ Fin ) → ( 𝑧𝑧𝐴 𝑧 ) )
41 34 40 syld ( ( 𝑧𝐴𝑧 ∈ Fin ) → ( 𝑧 ≠ ∅ → 𝐴 𝑧 ) )
42 26 41 pm2.61dne ( ( 𝑧𝐴𝑧 ∈ Fin ) → 𝐴 𝑧 )
43 13 42 syl ( 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) → 𝐴 𝑧 )
44 43 neneqd ( 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) → ¬ 𝐴 = 𝑧 )
45 44 nrex ¬ ∃ 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) 𝐴 = 𝑧
46 unieq ( 𝑦 = 𝐴 𝑦 = 𝐴 )
47 46 eqeq2d ( 𝑦 = 𝐴 → ( 𝐴 = 𝑦𝐴 = 𝐴 ) )
48 pweq ( 𝑦 = 𝐴 → 𝒫 𝑦 = 𝒫 𝐴 )
49 48 ineq1d ( 𝑦 = 𝐴 → ( 𝒫 𝑦 ∩ Fin ) = ( 𝒫 𝐴 ∩ Fin ) )
50 49 rexeqdv ( 𝑦 = 𝐴 → ( ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ↔ ∃ 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) 𝐴 = 𝑧 ) )
51 50 notbid ( 𝑦 = 𝐴 → ( ¬ ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ↔ ¬ ∃ 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) 𝐴 = 𝑧 ) )
52 47 51 anbi12d ( 𝑦 = 𝐴 → ( ( 𝐴 = 𝑦 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) ↔ ( 𝐴 = 𝐴 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) 𝐴 = 𝑧 ) ) )
53 52 rspcev ( ( 𝐴 ∈ 𝒫 suc 𝐴 ∧ ( 𝐴 = 𝐴 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝐴 ∩ Fin ) 𝐴 = 𝑧 ) ) → ∃ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
54 9 45 53 mpanr12 ( 𝐴 ∈ 𝒫 suc 𝐴 → ∃ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
55 rexanali ( ∃ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 ∧ ¬ ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) ↔ ¬ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
56 54 55 sylib ( 𝐴 ∈ 𝒫 suc 𝐴 → ¬ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
57 4 7 56 3syl ( suc 𝐴 ∈ Top → ¬ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
58 imnan ( ( suc 𝐴 ∈ Top → ¬ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) ) ↔ ¬ ( suc 𝐴 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) ) )
59 57 58 mpbi ¬ ( suc 𝐴 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) )
60 ordunisuc ( Ord 𝐴 suc 𝐴 = 𝐴 )
61 1 27 60 mp2b suc 𝐴 = 𝐴
62 61 eqcomi 𝐴 = suc 𝐴
63 62 iscmp ( suc 𝐴 ∈ Comp ↔ ( suc 𝐴 ∈ Top ∧ ∀ 𝑦 ∈ 𝒫 suc 𝐴 ( 𝐴 = 𝑦 → ∃ 𝑧 ∈ ( 𝒫 𝑦 ∩ Fin ) 𝐴 = 𝑧 ) ) )
64 59 63 mtbir ¬ suc 𝐴 ∈ Comp