Metamath Proof Explorer


Theorem zlmds

Description: Distance in a ZZ -module (if present). (Contributed by Thierry Arnoux, 8-Nov-2017) (Proof shortened by AV, 11-Nov-2024)

Ref Expression
Hypotheses zlmlem2.1 𝑊 = ( ℤMod ‘ 𝐺 )
zlmds.1 𝐷 = ( dist ‘ 𝐺 )
Assertion zlmds ( 𝐺𝑉𝐷 = ( dist ‘ 𝑊 ) )

Proof

Step Hyp Ref Expression
1 zlmlem2.1 𝑊 = ( ℤMod ‘ 𝐺 )
2 zlmds.1 𝐷 = ( dist ‘ 𝐺 )
3 eqid ( .g𝐺 ) = ( .g𝐺 )
4 1 3 zlmval ( 𝐺𝑉𝑊 = ( ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) sSet ⟨ ( ·𝑠 ‘ ndx ) , ( .g𝐺 ) ⟩ ) )
5 4 fveq2d ( 𝐺𝑉 → ( dist ‘ 𝑊 ) = ( dist ‘ ( ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) sSet ⟨ ( ·𝑠 ‘ ndx ) , ( .g𝐺 ) ⟩ ) ) )
6 dsid dist = Slot ( dist ‘ ndx )
7 slotsdnscsi ( ( dist ‘ ndx ) ≠ ( Scalar ‘ ndx ) ∧ ( dist ‘ ndx ) ≠ ( ·𝑠 ‘ ndx ) ∧ ( dist ‘ ndx ) ≠ ( ·𝑖 ‘ ndx ) )
8 7 simp1i ( dist ‘ ndx ) ≠ ( Scalar ‘ ndx )
9 6 8 setsnid ( dist ‘ 𝐺 ) = ( dist ‘ ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) )
10 7 simp2i ( dist ‘ ndx ) ≠ ( ·𝑠 ‘ ndx )
11 6 10 setsnid ( dist ‘ ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) ) = ( dist ‘ ( ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) sSet ⟨ ( ·𝑠 ‘ ndx ) , ( .g𝐺 ) ⟩ ) )
12 9 11 eqtri ( dist ‘ 𝐺 ) = ( dist ‘ ( ( 𝐺 sSet ⟨ ( Scalar ‘ ndx ) , ℤring ⟩ ) sSet ⟨ ( ·𝑠 ‘ ndx ) , ( .g𝐺 ) ⟩ ) )
13 5 12 eqtr4di ( 𝐺𝑉 → ( dist ‘ 𝑊 ) = ( dist ‘ 𝐺 ) )
14 2 13 eqtr4id ( 𝐺𝑉𝐷 = ( dist ‘ 𝑊 ) )