Definition df-isom 5226

Description: Define the isomorphism predicate. We read this as "𝐻 is an 𝑅, 𝑆 isomorphism of 𝐴 onto 𝐵". Normally, 𝑅 and 𝑆 are ordering relations on 𝐴 and 𝐵 respectively. Definition 6.28 of [TakeutiZaring] p. 32, whose notation is the same as ours except that 𝑅 and 𝑆 are subscripts. (Contributed by NM, 4-Mar-1997.)

Assertion

Ref	Expression
df-isom	⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ↔ (𝐻:𝐴–1-1-onto→𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦))))

Distinct variable groups:   𝑥,𝑦,𝐴   𝑥,𝐵,𝑦   𝑥,𝑅,𝑦   𝑥,𝑆,𝑦   𝑥,𝐻,𝑦

Detailed syntax breakdown of Definition df-isom

Step	Hyp	Ref	Expression
1		cA	. . 3 class 𝐴
2		cB	. . 3 class 𝐵
3		cR	. . 3 class 𝑅
4		cS	. . 3 class 𝑆
5		cH	. . 3 class 𝐻
6	1, 2, 3, 4, 5	wiso 5218	. 2 wff 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)
7	1, 2, 5	wf1o 5216	. . 3 wff 𝐻:𝐴–1-1-onto→𝐵
8		vx	. . . . . . . 8 setvar 𝑥
9	8	cv 1352	. . . . . . 7 class 𝑥
10		vy	. . . . . . . 8 setvar 𝑦
11	10	cv 1352	. . . . . . 7 class 𝑦
12	9, 11, 3	wbr 4004	. . . . . 6 wff 𝑥𝑅𝑦
13	9, 5	cfv 5217	. . . . . . 7 class (𝐻‘𝑥)
14	11, 5	cfv 5217	. . . . . . 7 class (𝐻‘𝑦)
15	13, 14, 4	wbr 4004	. . . . . 6 wff (𝐻‘𝑥)𝑆(𝐻‘𝑦)
16	12, 15	wb 105	. . . . 5 wff (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦))
17	16, 10, 1	wral 2455	. . . 4 wff ∀𝑦 ∈ 𝐴 (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦))
18	17, 8, 1	wral 2455	. . 3 wff ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦))
19	7, 18	wa 104	. 2 wff (𝐻:𝐴–1-1-onto→𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦)))
20	6, 19	wb 105	1 wff (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ↔ (𝐻:𝐴–1-1-onto→𝐵 ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐴 (𝑥𝑅𝑦 ↔ (𝐻‘𝑥)𝑆(𝐻‘𝑦))))

This definition is referenced by:  isoeq1  5802  isoeq2  5803  isoeq3  5804  isoeq4  5805  isoeq5  5806  nfiso  5807  isof1o  5808  isorel  5809  isoid  5811  isocnv  5812  isocnv2  5813  isores2  5814  isores3  5816  isotr  5817  iso0  5818  isoini2  5820  f1oiso  5827  negiso  8912  frec2uzisod  10407  zfz1isolem1  10820  xrnegiso  11270  reefiso  14201  logltb  14298