Metamath Proof Explorer


Theorem lanpropd

Description: If the categories have the same set of objects, morphisms, and compositions, then they have the same left Kan extensions. (Contributed by Zhi Wang, 21-Nov-2025)

Ref Expression
Hypotheses lanpropd.1 ( 𝜑 → ( Homf𝐴 ) = ( Homf𝐵 ) )
lanpropd.2 ( 𝜑 → ( compf𝐴 ) = ( compf𝐵 ) )
lanpropd.3 ( 𝜑 → ( Homf𝐶 ) = ( Homf𝐷 ) )
lanpropd.4 ( 𝜑 → ( compf𝐶 ) = ( compf𝐷 ) )
lanpropd.5 ( 𝜑 → ( Homf𝐸 ) = ( Homf𝐹 ) )
lanpropd.6 ( 𝜑 → ( compf𝐸 ) = ( compf𝐹 ) )
lanpropd.a ( 𝜑𝐴𝑉 )
lanpropd.b ( 𝜑𝐵𝑉 )
lanpropd.c ( 𝜑𝐶𝑉 )
lanpropd.d ( 𝜑𝐷𝑉 )
lanpropd.e ( 𝜑𝐸𝑉 )
lanpropd.f ( 𝜑𝐹𝑉 )
Assertion lanpropd ( 𝜑 → ( ⟨ 𝐴 , 𝐶 ⟩ Lan 𝐸 ) = ( ⟨ 𝐵 , 𝐷 ⟩ Lan 𝐹 ) )

Proof

Step Hyp Ref Expression
1 lanpropd.1 ( 𝜑 → ( Homf𝐴 ) = ( Homf𝐵 ) )
2 lanpropd.2 ( 𝜑 → ( compf𝐴 ) = ( compf𝐵 ) )
3 lanpropd.3 ( 𝜑 → ( Homf𝐶 ) = ( Homf𝐷 ) )
4 lanpropd.4 ( 𝜑 → ( compf𝐶 ) = ( compf𝐷 ) )
5 lanpropd.5 ( 𝜑 → ( Homf𝐸 ) = ( Homf𝐹 ) )
6 lanpropd.6 ( 𝜑 → ( compf𝐸 ) = ( compf𝐹 ) )
7 lanpropd.a ( 𝜑𝐴𝑉 )
8 lanpropd.b ( 𝜑𝐵𝑉 )
9 lanpropd.c ( 𝜑𝐶𝑉 )
10 lanpropd.d ( 𝜑𝐷𝑉 )
11 lanpropd.e ( 𝜑𝐸𝑉 )
12 lanpropd.f ( 𝜑𝐹𝑉 )
13 1 2 3 4 7 8 9 10 funcpropd ( 𝜑 → ( 𝐴 Func 𝐶 ) = ( 𝐵 Func 𝐷 ) )
14 1 2 5 6 7 8 11 12 funcpropd ( 𝜑 → ( 𝐴 Func 𝐸 ) = ( 𝐵 Func 𝐹 ) )
15 14 adantr ( ( 𝜑𝑓 ∈ ( 𝐴 Func 𝐶 ) ) → ( 𝐴 Func 𝐸 ) = ( 𝐵 Func 𝐹 ) )
16 3 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( Homf𝐶 ) = ( Homf𝐷 ) )
17 4 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( compf𝐶 ) = ( compf𝐷 ) )
18 5 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( Homf𝐸 ) = ( Homf𝐹 ) )
19 6 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( compf𝐸 ) = ( compf𝐹 ) )
20 funcrcl ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) → ( 𝐴 ∈ Cat ∧ 𝐶 ∈ Cat ) )
21 20 ad2antrl ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐴 ∈ Cat ∧ 𝐶 ∈ Cat ) )
22 21 simprd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐶 ∈ Cat )
23 10 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐷𝑉 )
24 16 17 22 23 catpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐶 ∈ Cat ↔ 𝐷 ∈ Cat ) )
25 22 24 mpbid ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐷 ∈ Cat )
26 funcrcl ( 𝑥 ∈ ( 𝐴 Func 𝐸 ) → ( 𝐴 ∈ Cat ∧ 𝐸 ∈ Cat ) )
27 26 ad2antll ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐴 ∈ Cat ∧ 𝐸 ∈ Cat ) )
28 27 simprd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐸 ∈ Cat )
29 12 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐹𝑉 )
30 18 19 28 29 catpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐸 ∈ Cat ↔ 𝐹 ∈ Cat ) )
31 28 30 mpbid ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐹 ∈ Cat )
32 16 17 18 19 22 25 28 31 fucpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐶 FuncCat 𝐸 ) = ( 𝐷 FuncCat 𝐹 ) )
33 1 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( Homf𝐴 ) = ( Homf𝐵 ) )
34 2 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( compf𝐴 ) = ( compf𝐵 ) )
35 21 simpld ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐴 ∈ Cat )
36 8 adantr ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐵𝑉 )
37 33 34 35 36 catpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐴 ∈ Cat ↔ 𝐵 ∈ Cat ) )
38 35 37 mpbid ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝐵 ∈ Cat )
39 33 34 18 19 35 38 28 31 fucpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( 𝐴 FuncCat 𝐸 ) = ( 𝐵 FuncCat 𝐹 ) )
40 32 39 oveq12d ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( ( 𝐶 FuncCat 𝐸 ) UP ( 𝐴 FuncCat 𝐸 ) ) = ( ( 𝐷 FuncCat 𝐹 ) UP ( 𝐵 FuncCat 𝐹 ) ) )
41 simprl ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝑓 ∈ ( 𝐴 Func 𝐶 ) )
42 16 17 18 19 22 25 28 31 41 prcofpropd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( ⟨ 𝐶 , 𝐸 ⟩ −∘F 𝑓 ) = ( ⟨ 𝐷 , 𝐹 ⟩ −∘F 𝑓 ) )
43 eqidd ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → 𝑥 = 𝑥 )
44 40 42 43 oveq123d ( ( 𝜑 ∧ ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) ∧ 𝑥 ∈ ( 𝐴 Func 𝐸 ) ) ) → ( ( ⟨ 𝐶 , 𝐸 ⟩ −∘F 𝑓 ) ( ( 𝐶 FuncCat 𝐸 ) UP ( 𝐴 FuncCat 𝐸 ) ) 𝑥 ) = ( ( ⟨ 𝐷 , 𝐹 ⟩ −∘F 𝑓 ) ( ( 𝐷 FuncCat 𝐹 ) UP ( 𝐵 FuncCat 𝐹 ) ) 𝑥 ) )
45 13 15 44 mpoeq123dva ( 𝜑 → ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) , 𝑥 ∈ ( 𝐴 Func 𝐸 ) ↦ ( ( ⟨ 𝐶 , 𝐸 ⟩ −∘F 𝑓 ) ( ( 𝐶 FuncCat 𝐸 ) UP ( 𝐴 FuncCat 𝐸 ) ) 𝑥 ) ) = ( 𝑓 ∈ ( 𝐵 Func 𝐷 ) , 𝑥 ∈ ( 𝐵 Func 𝐹 ) ↦ ( ( ⟨ 𝐷 , 𝐹 ⟩ −∘F 𝑓 ) ( ( 𝐷 FuncCat 𝐹 ) UP ( 𝐵 FuncCat 𝐹 ) ) 𝑥 ) ) )
46 eqid ( 𝐶 FuncCat 𝐸 ) = ( 𝐶 FuncCat 𝐸 )
47 eqid ( 𝐴 FuncCat 𝐸 ) = ( 𝐴 FuncCat 𝐸 )
48 46 47 7 9 11 lanfval ( 𝜑 → ( ⟨ 𝐴 , 𝐶 ⟩ Lan 𝐸 ) = ( 𝑓 ∈ ( 𝐴 Func 𝐶 ) , 𝑥 ∈ ( 𝐴 Func 𝐸 ) ↦ ( ( ⟨ 𝐶 , 𝐸 ⟩ −∘F 𝑓 ) ( ( 𝐶 FuncCat 𝐸 ) UP ( 𝐴 FuncCat 𝐸 ) ) 𝑥 ) ) )
49 eqid ( 𝐷 FuncCat 𝐹 ) = ( 𝐷 FuncCat 𝐹 )
50 eqid ( 𝐵 FuncCat 𝐹 ) = ( 𝐵 FuncCat 𝐹 )
51 49 50 8 10 12 lanfval ( 𝜑 → ( ⟨ 𝐵 , 𝐷 ⟩ Lan 𝐹 ) = ( 𝑓 ∈ ( 𝐵 Func 𝐷 ) , 𝑥 ∈ ( 𝐵 Func 𝐹 ) ↦ ( ( ⟨ 𝐷 , 𝐹 ⟩ −∘F 𝑓 ) ( ( 𝐷 FuncCat 𝐹 ) UP ( 𝐵 FuncCat 𝐹 ) ) 𝑥 ) ) )
52 45 48 51 3eqtr4d ( 𝜑 → ( ⟨ 𝐴 , 𝐶 ⟩ Lan 𝐸 ) = ( ⟨ 𝐵 , 𝐷 ⟩ Lan 𝐹 ) )