Metamath Proof Explorer


Theorem cntzsnid

Description: The centralizer of the identity element is the whole base set. (Contributed by Thierry Arnoux, 27-Nov-2023)

Ref Expression
Hypotheses cntzun.b
|- B = ( Base ` M )
cntzun.z
|- Z = ( Cntz ` M )
cntzsnid.1
|- .0. = ( 0g ` M )
Assertion cntzsnid
|- ( M e. Mnd -> ( Z ` { .0. } ) = B )

Proof

Step Hyp Ref Expression
1 cntzun.b
 |-  B = ( Base ` M )
2 cntzun.z
 |-  Z = ( Cntz ` M )
3 cntzsnid.1
 |-  .0. = ( 0g ` M )
4 1 3 mndidcl
 |-  ( M e. Mnd -> .0. e. B )
5 eqid
 |-  ( +g ` M ) = ( +g ` M )
6 1 5 2 elcntzsn
 |-  ( .0. e. B -> ( x e. ( Z ` { .0. } ) <-> ( x e. B /\ ( x ( +g ` M ) .0. ) = ( .0. ( +g ` M ) x ) ) ) )
7 4 6 syl
 |-  ( M e. Mnd -> ( x e. ( Z ` { .0. } ) <-> ( x e. B /\ ( x ( +g ` M ) .0. ) = ( .0. ( +g ` M ) x ) ) ) )
8 1 5 3 mndrid
 |-  ( ( M e. Mnd /\ x e. B ) -> ( x ( +g ` M ) .0. ) = x )
9 1 5 3 mndlid
 |-  ( ( M e. Mnd /\ x e. B ) -> ( .0. ( +g ` M ) x ) = x )
10 8 9 eqtr4d
 |-  ( ( M e. Mnd /\ x e. B ) -> ( x ( +g ` M ) .0. ) = ( .0. ( +g ` M ) x ) )
11 10 ex
 |-  ( M e. Mnd -> ( x e. B -> ( x ( +g ` M ) .0. ) = ( .0. ( +g ` M ) x ) ) )
12 11 pm4.71d
 |-  ( M e. Mnd -> ( x e. B <-> ( x e. B /\ ( x ( +g ` M ) .0. ) = ( .0. ( +g ` M ) x ) ) ) )
13 7 12 bitr4d
 |-  ( M e. Mnd -> ( x e. ( Z ` { .0. } ) <-> x e. B ) )
14 13 eqrdv
 |-  ( M e. Mnd -> ( Z ` { .0. } ) = B )