Metamath Proof Explorer


Theorem gchaleph

Description: If ( alephA ) is a GCH-set and its powerset is well-orderable, then the successor aleph ( alephsuc A ) is equinumerous to the powerset of ( alephA ) . (Contributed by Mario Carneiro, 15-May-2015)

Ref Expression
Assertion gchaleph A On A GCH 𝒫 A dom card suc A 𝒫 A

Proof

Step Hyp Ref Expression
1 alephsucpw2 ¬ 𝒫 A suc A
2 alephon suc A On
3 onenon suc A On suc A dom card
4 2 3 ax-mp suc A dom card
5 simp3 A On A GCH 𝒫 A dom card 𝒫 A dom card
6 domtri2 suc A dom card 𝒫 A dom card suc A 𝒫 A ¬ 𝒫 A suc A
7 4 5 6 sylancr A On A GCH 𝒫 A dom card suc A 𝒫 A ¬ 𝒫 A suc A
8 1 7 mpbiri A On A GCH 𝒫 A dom card suc A 𝒫 A
9 fvex A V
10 simp1 A On A GCH 𝒫 A dom card A On
11 alephgeom A On ω A
12 10 11 sylib A On A GCH 𝒫 A dom card ω A
13 ssdomg A V ω A ω A
14 9 12 13 mpsyl A On A GCH 𝒫 A dom card ω A
15 domnsym ω A ¬ A ω
16 14 15 syl A On A GCH 𝒫 A dom card ¬ A ω
17 isfinite A Fin A ω
18 16 17 sylnibr A On A GCH 𝒫 A dom card ¬ A Fin
19 simp2 A On A GCH 𝒫 A dom card A GCH
20 alephordilem1 A On A suc A
21 20 3ad2ant1 A On A GCH 𝒫 A dom card A suc A
22 gchi A GCH A suc A suc A 𝒫 A A Fin
23 22 3expia A GCH A suc A suc A 𝒫 A A Fin
24 19 21 23 syl2anc A On A GCH 𝒫 A dom card suc A 𝒫 A A Fin
25 18 24 mtod A On A GCH 𝒫 A dom card ¬ suc A 𝒫 A
26 domtri2 𝒫 A dom card suc A dom card 𝒫 A suc A ¬ suc A 𝒫 A
27 5 4 26 sylancl A On A GCH 𝒫 A dom card 𝒫 A suc A ¬ suc A 𝒫 A
28 25 27 mpbird A On A GCH 𝒫 A dom card 𝒫 A suc A
29 sbth suc A 𝒫 A 𝒫 A suc A suc A 𝒫 A
30 8 28 29 syl2anc A On A GCH 𝒫 A dom card suc A 𝒫 A