Metamath Proof Explorer


Definition df-cv

Description: Define the covers relation (on the Hilbert lattice). Definition 3.2.18 of PtakPulmannova p. 68, whose notation we use. Ptak/Pulmannova's notation A is read " B covers A " or " A is covered by B " , and it means that B is larger than A and there is nothing in between. See cvbr and cvbr2 for membership relations. (Contributed by NM, 4-Jun-2004) (New usage is discouraged.)

Ref Expression
Assertion df-cv = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥C𝑦C ) ∧ ( 𝑥𝑦 ∧ ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 ) ) ) }

Detailed syntax breakdown

Step Hyp Ref Expression
0 ccv
1 vx 𝑥
2 vy 𝑦
3 1 cv 𝑥
4 cch C
5 3 4 wcel 𝑥C
6 2 cv 𝑦
7 6 4 wcel 𝑦C
8 5 7 wa ( 𝑥C𝑦C )
9 3 6 wpss 𝑥𝑦
10 vz 𝑧
11 10 cv 𝑧
12 3 11 wpss 𝑥𝑧
13 11 6 wpss 𝑧𝑦
14 12 13 wa ( 𝑥𝑧𝑧𝑦 )
15 14 10 4 wrex 𝑧C ( 𝑥𝑧𝑧𝑦 )
16 15 wn ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 )
17 9 16 wa ( 𝑥𝑦 ∧ ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 ) )
18 8 17 wa ( ( 𝑥C𝑦C ) ∧ ( 𝑥𝑦 ∧ ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 ) ) )
19 18 1 2 copab { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥C𝑦C ) ∧ ( 𝑥𝑦 ∧ ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 ) ) ) }
20 0 19 wceq = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥C𝑦C ) ∧ ( 𝑥𝑦 ∧ ¬ ∃ 𝑧C ( 𝑥𝑧𝑧𝑦 ) ) ) }