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Theorem yoneda 18329
Description: The Yoneda Lemma. There is a natural isomorphism between the functors 𝑍 and 𝐸, where 𝑍(𝐹, 𝑋) is the natural transformations from Yon(𝑋) = Hom ( − , 𝑋) to 𝐹, and 𝐸(𝐹, 𝑋) = 𝐹(𝑋) is the evaluation functor. Here we need two universes to state the claim: the smaller universe 𝑈 is used for forming the functor category 𝑄 = 𝐶 op → SetCat(𝑈), which itself does not (necessarily) live in 𝑈 but instead is an element of the larger universe 𝑉. (If 𝑈 is a Grothendieck universe, then it will be closed under this "presheaf" operation, and so we can set 𝑈 = 𝑉 in this case.) (Contributed by Mario Carneiro, 29-Jan-2017.)
Hypotheses
Ref Expression
yoneda.y 𝑌 = (Yon‘𝐶)
yoneda.b 𝐵 = (Base‘𝐶)
yoneda.1 1 = (Id‘𝐶)
yoneda.o 𝑂 = (oppCat‘𝐶)
yoneda.s 𝑆 = (SetCat‘𝑈)
yoneda.t 𝑇 = (SetCat‘𝑉)
yoneda.q 𝑄 = (𝑂 FuncCat 𝑆)
yoneda.h 𝐻 = (HomF𝑄)
yoneda.r 𝑅 = ((𝑄 ×c 𝑂) FuncCat 𝑇)
yoneda.e 𝐸 = (𝑂 evalF 𝑆)
yoneda.z 𝑍 = (𝐻func ((⟨(1st𝑌), tpos (2nd𝑌)⟩ ∘func (𝑄 2ndF 𝑂)) ⟨,⟩F (𝑄 1stF 𝑂)))
yoneda.c (𝜑𝐶 ∈ Cat)
yoneda.w (𝜑𝑉𝑊)
yoneda.u (𝜑 → ran (Homf𝐶) ⊆ 𝑈)
yoneda.v (𝜑 → (ran (Homf𝑄) ∪ 𝑈) ⊆ 𝑉)
yoneda.m 𝑀 = (𝑓 ∈ (𝑂 Func 𝑆), 𝑥𝐵 ↦ (𝑎 ∈ (((1st𝑌)‘𝑥)(𝑂 Nat 𝑆)𝑓) ↦ ((𝑎𝑥)‘( 1𝑥))))
yoneda.i 𝐼 = (Iso‘𝑅)
Assertion
Ref Expression
yoneda (𝜑𝑀 ∈ (𝑍𝐼𝐸))
Distinct variable groups:   𝑓,𝑎,𝑥, 1   𝐶,𝑎,𝑓,𝑥   𝐸,𝑎,𝑓   𝐵,𝑎,𝑓,𝑥   𝑂,𝑎,𝑓,𝑥   𝑆,𝑎,𝑓,𝑥   𝑄,𝑎,𝑓,𝑥   𝑇,𝑓   𝜑,𝑎,𝑓,𝑥   𝑌,𝑎,𝑓,𝑥   𝑍,𝑎,𝑓,𝑥
Allowed substitution hints:   𝑅(𝑥,𝑓,𝑎)   𝑇(𝑥,𝑎)   𝑈(𝑥,𝑓,𝑎)   𝐸(𝑥)   𝐻(𝑥,𝑓,𝑎)   𝐼(𝑥,𝑓,𝑎)   𝑀(𝑥,𝑓,𝑎)   𝑉(𝑥,𝑓,𝑎)   𝑊(𝑥,𝑓,𝑎)

Proof of Theorem yoneda
Dummy variables 𝑔 𝑦 𝑢 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 yoneda.r . . 3 𝑅 = ((𝑄 ×c 𝑂) FuncCat 𝑇)
21fucbas 18005 . 2 ((𝑄 ×c 𝑂) Func 𝑇) = (Base‘𝑅)
3 eqid 2733 . 2 (Inv‘𝑅) = (Inv‘𝑅)
4 yoneda.y . . . . . . 7 𝑌 = (Yon‘𝐶)
5 yoneda.b . . . . . . 7 𝐵 = (Base‘𝐶)
6 yoneda.1 . . . . . . 7 1 = (Id‘𝐶)
7 yoneda.o . . . . . . 7 𝑂 = (oppCat‘𝐶)
8 yoneda.s . . . . . . 7 𝑆 = (SetCat‘𝑈)
9 yoneda.t . . . . . . 7 𝑇 = (SetCat‘𝑉)
10 yoneda.q . . . . . . 7 𝑄 = (𝑂 FuncCat 𝑆)
11 yoneda.h . . . . . . 7 𝐻 = (HomF𝑄)
12 yoneda.e . . . . . . 7 𝐸 = (𝑂 evalF 𝑆)
13 yoneda.z . . . . . . 7 𝑍 = (𝐻func ((⟨(1st𝑌), tpos (2nd𝑌)⟩ ∘func (𝑄 2ndF 𝑂)) ⟨,⟩F (𝑄 1stF 𝑂)))
14 yoneda.c . . . . . . 7 (𝜑𝐶 ∈ Cat)
15 yoneda.w . . . . . . 7 (𝜑𝑉𝑊)
16 yoneda.u . . . . . . 7 (𝜑 → ran (Homf𝐶) ⊆ 𝑈)
17 yoneda.v . . . . . . 7 (𝜑 → (ran (Homf𝑄) ∪ 𝑈) ⊆ 𝑉)
184, 5, 6, 7, 8, 9, 10, 11, 1, 12, 13, 14, 15, 16, 17yonedalem1 18318 . . . . . 6 (𝜑 → (𝑍 ∈ ((𝑄 ×c 𝑂) Func 𝑇) ∧ 𝐸 ∈ ((𝑄 ×c 𝑂) Func 𝑇)))
1918simpld 494 . . . . 5 (𝜑𝑍 ∈ ((𝑄 ×c 𝑂) Func 𝑇))
20 funcrcl 17903 . . . . 5 (𝑍 ∈ ((𝑄 ×c 𝑂) Func 𝑇) → ((𝑄 ×c 𝑂) ∈ Cat ∧ 𝑇 ∈ Cat))
2119, 20syl 17 . . . 4 (𝜑 → ((𝑄 ×c 𝑂) ∈ Cat ∧ 𝑇 ∈ Cat))
2221simpld 494 . . 3 (𝜑 → (𝑄 ×c 𝑂) ∈ Cat)
2321simprd 495 . . 3 (𝜑𝑇 ∈ Cat)
241, 22, 23fuccat 18016 . 2 (𝜑𝑅 ∈ Cat)
2518simprd 495 . 2 (𝜑𝐸 ∈ ((𝑄 ×c 𝑂) Func 𝑇))
26 yoneda.i . 2 𝐼 = (Iso‘𝑅)
27 yoneda.m . . 3 𝑀 = (𝑓 ∈ (𝑂 Func 𝑆), 𝑥𝐵 ↦ (𝑎 ∈ (((1st𝑌)‘𝑥)(𝑂 Nat 𝑆)𝑓) ↦ ((𝑎𝑥)‘( 1𝑥))))
28 eqid 2733 . . 3 (𝑓 ∈ (𝑂 Func 𝑆), 𝑥𝐵 ↦ (𝑢 ∈ ((1st𝑓)‘𝑥) ↦ (𝑦𝐵 ↦ (𝑔 ∈ (𝑦(Hom ‘𝐶)𝑥) ↦ (((𝑥(2nd𝑓)𝑦)‘𝑔)‘𝑢))))) = (𝑓 ∈ (𝑂 Func 𝑆), 𝑥𝐵 ↦ (𝑢 ∈ ((1st𝑓)‘𝑥) ↦ (𝑦𝐵 ↦ (𝑔 ∈ (𝑦(Hom ‘𝐶)𝑥) ↦ (((𝑥(2nd𝑓)𝑦)‘𝑔)‘𝑢)))))
294, 5, 6, 7, 8, 9, 10, 11, 1, 12, 13, 14, 15, 16, 17, 27, 3, 28yonedainv 18327 . 2 (𝜑𝑀(𝑍(Inv‘𝑅)𝐸)(𝑓 ∈ (𝑂 Func 𝑆), 𝑥𝐵 ↦ (𝑢 ∈ ((1st𝑓)‘𝑥) ↦ (𝑦𝐵 ↦ (𝑔 ∈ (𝑦(Hom ‘𝐶)𝑥) ↦ (((𝑥(2nd𝑓)𝑦)‘𝑔)‘𝑢))))))
302, 3, 24, 19, 25, 26, 29inviso1 17803 1 (𝜑𝑀 ∈ (𝑍𝐼𝐸))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 395   = wceq 1535  wcel 2104  cun 3961  wss 3963  cop 4636  cmpt 5232  ran crn 5684  cfv 6558  (class class class)co 7425  cmpo 7427  1st c1st 8005  2nd c2nd 8006  tpos ctpos 8243  Basecbs 17234  Hom chom 17298  Catccat 17698  Idccid 17699  Homf chomf 17700  oppCatcoppc 17745  Invcinv 17782  Isociso 17783   Func cfunc 17894  func ccofu 17896   Nat cnat 17985   FuncCat cfuc 17986  SetCatcsetc 18118   ×c cxpc 18213   1stF c1stf 18214   2ndF c2ndf 18215   ⟨,⟩F cprf 18216   evalF cevlf 18255  HomFchof 18294  Yoncyon 18295
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1790  ax-4 1804  ax-5 1906  ax-6 1963  ax-7 2003  ax-8 2106  ax-9 2114  ax-10 2137  ax-11 2153  ax-12 2173  ax-ext 2704  ax-rep 5286  ax-sep 5300  ax-nul 5307  ax-pow 5366  ax-pr 5430  ax-un 7747  ax-cnex 11202  ax-resscn 11203  ax-1cn 11204  ax-icn 11205  ax-addcl 11206  ax-addrcl 11207  ax-mulcl 11208  ax-mulrcl 11209  ax-mulcom 11210  ax-addass 11211  ax-mulass 11212  ax-distr 11213  ax-i2m1 11214  ax-1ne0 11215  ax-1rid 11216  ax-rnegex 11217  ax-rrecex 11218  ax-cnre 11219  ax-pre-lttri 11220  ax-pre-lttrn 11221  ax-pre-ltadd 11222  ax-pre-mulgt0 11223
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 847  df-3or 1086  df-3an 1087  df-tru 1538  df-fal 1548  df-ex 1775  df-nf 1779  df-sb 2061  df-mo 2536  df-eu 2565  df-clab 2711  df-cleq 2725  df-clel 2812  df-nfc 2888  df-ne 2937  df-nel 3043  df-ral 3058  df-rex 3067  df-rmo 3376  df-reu 3377  df-rab 3433  df-v 3479  df-sbc 3792  df-csb 3909  df-dif 3966  df-un 3968  df-in 3970  df-ss 3980  df-pss 3983  df-nul 4340  df-if 4531  df-pw 4606  df-sn 4631  df-pr 4633  df-tp 4635  df-op 4637  df-uni 4915  df-iun 5000  df-br 5150  df-opab 5212  df-mpt 5233  df-tr 5267  df-id 5576  df-eprel 5582  df-po 5590  df-so 5591  df-fr 5635  df-we 5637  df-xp 5689  df-rel 5690  df-cnv 5691  df-co 5692  df-dm 5693  df-rn 5694  df-res 5695  df-ima 5696  df-pred 6317  df-ord 6383  df-on 6384  df-lim 6385  df-suc 6386  df-iota 6510  df-fun 6560  df-fn 6561  df-f 6562  df-f1 6563  df-fo 6564  df-f1o 6565  df-fv 6566  df-riota 7381  df-ov 7428  df-oprab 7429  df-mpo 7430  df-om 7881  df-1st 8007  df-2nd 8008  df-tpos 8244  df-frecs 8299  df-wrecs 8330  df-recs 8404  df-rdg 8443  df-1o 8499  df-er 8738  df-map 8861  df-pm 8862  df-ixp 8931  df-en 8979  df-dom 8980  df-sdom 8981  df-fin 8982  df-pnf 11288  df-mnf 11289  df-xr 11290  df-ltxr 11291  df-le 11292  df-sub 11485  df-neg 11486  df-nn 12258  df-2 12320  df-3 12321  df-4 12322  df-5 12323  df-6 12324  df-7 12325  df-8 12326  df-9 12327  df-n0 12518  df-z 12605  df-dec 12725  df-uz 12870  df-fz 13538  df-struct 17170  df-sets 17187  df-slot 17205  df-ndx 17217  df-base 17235  df-ress 17264  df-hom 17311  df-cco 17312  df-cat 17702  df-cid 17703  df-homf 17704  df-comf 17705  df-oppc 17746  df-sect 17784  df-inv 17785  df-iso 17786  df-ssc 17847  df-resc 17848  df-subc 17849  df-func 17898  df-cofu 17900  df-nat 17987  df-fuc 17988  df-setc 18119  df-xpc 18217  df-1stf 18218  df-2ndf 18219  df-prf 18220  df-evlf 18259  df-curf 18260  df-hof 18296  df-yon 18297
This theorem is referenced by: (None)
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