Theorem infxpidm 10328

Description: Every infinite class is equinumerous to its Cartesian square. This theorem, which is equivalent to the axiom of choice over ZF, provides the basis for infinite cardinal arithmetic. Proposition 10.40 of [TakeutiZaring] p. 95. This is a corollary of infxpen 9780 (used via infxpidm2 9783). (Contributed by NM, 17-Sep-2004.) (Revised by Mario Carneiro, 9-Mar-2013.)

Assertion

Ref	Expression
infxpidm	⊢ (ω ≼ 𝐴 → (𝐴 × 𝐴) ≈ 𝐴)

Proof of Theorem infxpidm

Step	Hyp	Ref	Expression
1		reldom 8726	. . . 4 ⊢ Rel ≼
2	1	brrelex2i 5639	. . 3 ⊢ (ω ≼ 𝐴 → 𝐴 ∈ V)
3		numth3 10236	. . 3 ⊢ (𝐴 ∈ V → 𝐴 ∈ dom card)
4	2, 3	syl 17	. 2 ⊢ (ω ≼ 𝐴 → 𝐴 ∈ dom card)
5		infxpidm2 9783	. 2 ⊢ ((𝐴 ∈ dom card ∧ ω ≼ 𝐴) → (𝐴 × 𝐴) ≈ 𝐴)
6	4, 5	mpancom 685	1 ⊢ (ω ≼ 𝐴 → (𝐴 × 𝐴) ≈ 𝐴)

Syntax hints:   → wi 4   ∈ wcel 2106  Vcvv 3429   class class class wbr 5073   × cxp 5582  dom cdm 5584  ωcom 7702   ≈ cen 8717   ≼ cdom 8718  cardccrd 9703

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2709  ax-rep 5208  ax-sep 5221  ax-nul 5228  ax-pow 5286  ax-pr 5350  ax-un 7578  ax-inf2 9386  ax-ac2 10229

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-3or 1087  df-3an 1088  df-tru 1542  df-fal 1552  df-ex 1783  df-nf 1787  df-sb 2068  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2816  df-nfc 2889  df-ne 2944  df-ral 3069  df-rex 3070  df-reu 3071  df-rmo 3072  df-rab 3073  df-v 3431  df-sbc 3716  df-csb 3832  df-dif 3889  df-un 3891  df-in 3893  df-ss 3903  df-pss 3905  df-nul 4257  df-if 4460  df-pw 4535  df-sn 4562  df-pr 4564  df-op 4568  df-uni 4840  df-int 4880  df-iun 4926  df-br 5074  df-opab 5136  df-mpt 5157  df-tr 5191  df-id 5484  df-eprel 5490  df-po 5498  df-so 5499  df-fr 5539  df-se 5540  df-we 5541  df-xp 5590  df-rel 5591  df-cnv 5592  df-co 5593  df-dm 5594  df-rn 5595  df-res 5596  df-ima 5597  df-pred 6195  df-ord 6262  df-on 6263  df-lim 6264  df-suc 6265  df-iota 6384  df-fun 6428  df-fn 6429  df-f 6430  df-f1 6431  df-fo 6432  df-f1o 6433  df-fv 6434  df-isom 6435  df-riota 7224  df-ov 7270  df-om 7703  df-1st 7820  df-2nd 7821  df-frecs 8084  df-wrecs 8115  df-recs 8189  df-rdg 8228  df-1o 8284  df-er 8485  df-en 8721  df-dom 8722  df-sdom 8723  df-fin 8724  df-oi 9256  df-card 9707  df-ac 9882

This theorem is referenced by:  unirnfdomd  10333  inar1  10541