Metamath Proof Explorer


Theorem dssmapclsntr

Description: The closure and interior operators on a topology are duals of each other. See also kur14lem2 . (Contributed by RP, 22-Apr-2021)

Ref Expression
Hypotheses dssmapclsntr.x 𝑋 = 𝐽
dssmapclsntr.k 𝐾 = ( cls ‘ 𝐽 )
dssmapclsntr.i 𝐼 = ( int ‘ 𝐽 )
dssmapclsntr.o 𝑂 = ( 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝒫 𝑏 ) ↦ ( 𝑠 ∈ 𝒫 𝑏 ↦ ( 𝑏 ∖ ( 𝑓 ‘ ( 𝑏𝑠 ) ) ) ) ) )
dssmapclsntr.d 𝐷 = ( 𝑂𝑋 )
Assertion dssmapclsntr ( 𝐽 ∈ Top → 𝐾 = ( 𝐷𝐼 ) )

Proof

Step Hyp Ref Expression
1 dssmapclsntr.x 𝑋 = 𝐽
2 dssmapclsntr.k 𝐾 = ( cls ‘ 𝐽 )
3 dssmapclsntr.i 𝐼 = ( int ‘ 𝐽 )
4 dssmapclsntr.o 𝑂 = ( 𝑏 ∈ V ↦ ( 𝑓 ∈ ( 𝒫 𝑏m 𝒫 𝑏 ) ↦ ( 𝑠 ∈ 𝒫 𝑏 ↦ ( 𝑏 ∖ ( 𝑓 ‘ ( 𝑏𝑠 ) ) ) ) ) )
5 dssmapclsntr.d 𝐷 = ( 𝑂𝑋 )
6 1 2 3 4 5 dssmapntrcls ( 𝐽 ∈ Top → 𝐼 = ( 𝐷𝐾 ) )
7 6 eqcomd ( 𝐽 ∈ Top → ( 𝐷𝐾 ) = 𝐼 )
8 1 topopn ( 𝐽 ∈ Top → 𝑋𝐽 )
9 4 5 8 dssmapf1od ( 𝐽 ∈ Top → 𝐷 : ( 𝒫 𝑋m 𝒫 𝑋 ) –1-1-onto→ ( 𝒫 𝑋m 𝒫 𝑋 ) )
10 1 2 clselmap ( 𝐽 ∈ Top → 𝐾 ∈ ( 𝒫 𝑋m 𝒫 𝑋 ) )
11 f1ocnvfv ( ( 𝐷 : ( 𝒫 𝑋m 𝒫 𝑋 ) –1-1-onto→ ( 𝒫 𝑋m 𝒫 𝑋 ) ∧ 𝐾 ∈ ( 𝒫 𝑋m 𝒫 𝑋 ) ) → ( ( 𝐷𝐾 ) = 𝐼 → ( 𝐷𝐼 ) = 𝐾 ) )
12 9 10 11 syl2anc ( 𝐽 ∈ Top → ( ( 𝐷𝐾 ) = 𝐼 → ( 𝐷𝐼 ) = 𝐾 ) )
13 7 12 mpd ( 𝐽 ∈ Top → ( 𝐷𝐼 ) = 𝐾 )
14 4 5 8 dssmapnvod ( 𝐽 ∈ Top → 𝐷 = 𝐷 )
15 14 fveq1d ( 𝐽 ∈ Top → ( 𝐷𝐼 ) = ( 𝐷𝐼 ) )
16 13 15 eqtr3d ( 𝐽 ∈ Top → 𝐾 = ( 𝐷𝐼 ) )