Metamath Proof Explorer


Theorem mendvscafval

Description: Scalar multiplication in the module endomorphism algebra. (Contributed by Stefan O'Rear, 2-Sep-2015) (Proof shortened by AV, 3-Mar-2024)

Ref Expression
Hypotheses mendvscafval.a
|- A = ( MEndo ` M )
mendvscafval.v
|- .x. = ( .s ` M )
mendvscafval.b
|- B = ( Base ` A )
mendvscafval.s
|- S = ( Scalar ` M )
mendvscafval.k
|- K = ( Base ` S )
mendvscafval.e
|- E = ( Base ` M )
Assertion mendvscafval
|- ( .s ` A ) = ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) )

Proof

Step Hyp Ref Expression
1 mendvscafval.a
 |-  A = ( MEndo ` M )
2 mendvscafval.v
 |-  .x. = ( .s ` M )
3 mendvscafval.b
 |-  B = ( Base ` A )
4 mendvscafval.s
 |-  S = ( Scalar ` M )
5 mendvscafval.k
 |-  K = ( Base ` S )
6 mendvscafval.e
 |-  E = ( Base ` M )
7 1 fveq2i
 |-  ( .s ` A ) = ( .s ` ( MEndo ` M ) )
8 1 mendbas
 |-  ( M LMHom M ) = ( Base ` A )
9 3 8 eqtr4i
 |-  B = ( M LMHom M )
10 eqid
 |-  ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) = ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) )
11 eqid
 |-  ( x e. B , y e. B |-> ( x o. y ) ) = ( x e. B , y e. B |-> ( x o. y ) )
12 eqid
 |-  B = B
13 6 xpeq1i
 |-  ( E X. { x } ) = ( ( Base ` M ) X. { x } )
14 eqid
 |-  y = y
15 ofeq
 |-  ( .x. = ( .s ` M ) -> oF .x. = oF ( .s ` M ) )
16 2 15 ax-mp
 |-  oF .x. = oF ( .s ` M )
17 13 14 16 oveq123i
 |-  ( ( E X. { x } ) oF .x. y ) = ( ( ( Base ` M ) X. { x } ) oF ( .s ` M ) y )
18 5 12 17 mpoeq123i
 |-  ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) = ( x e. ( Base ` S ) , y e. B |-> ( ( ( Base ` M ) X. { x } ) oF ( .s ` M ) y ) )
19 9 10 11 4 18 mendval
 |-  ( M e. _V -> ( MEndo ` M ) = ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } ) )
20 19 fveq2d
 |-  ( M e. _V -> ( .s ` ( MEndo ` M ) ) = ( .s ` ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } ) ) )
21 5 fvexi
 |-  K e. _V
22 3 fvexi
 |-  B e. _V
23 21 22 mpoex
 |-  ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) e. _V
24 eqid
 |-  ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } ) = ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } )
25 24 algvsca
 |-  ( ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) e. _V -> ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) = ( .s ` ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } ) ) )
26 23 25 mp1i
 |-  ( M e. _V -> ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) = ( .s ` ( { <. ( Base ` ndx ) , B >. , <. ( +g ` ndx ) , ( x e. B , y e. B |-> ( x oF ( +g ` M ) y ) ) >. , <. ( .r ` ndx ) , ( x e. B , y e. B |-> ( x o. y ) ) >. } u. { <. ( Scalar ` ndx ) , S >. , <. ( .s ` ndx ) , ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) >. } ) ) )
27 20 26 eqtr4d
 |-  ( M e. _V -> ( .s ` ( MEndo ` M ) ) = ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) )
28 fvprc
 |-  ( -. M e. _V -> ( MEndo ` M ) = (/) )
29 28 fveq2d
 |-  ( -. M e. _V -> ( .s ` ( MEndo ` M ) ) = ( .s ` (/) ) )
30 df-vsca
 |-  .s = Slot 6
31 30 str0
 |-  (/) = ( .s ` (/) )
32 29 31 eqtr4di
 |-  ( -. M e. _V -> ( .s ` ( MEndo ` M ) ) = (/) )
33 fvprc
 |-  ( -. M e. _V -> ( Scalar ` M ) = (/) )
34 4 33 syl5eq
 |-  ( -. M e. _V -> S = (/) )
35 34 fveq2d
 |-  ( -. M e. _V -> ( Base ` S ) = ( Base ` (/) ) )
36 base0
 |-  (/) = ( Base ` (/) )
37 35 5 36 3eqtr4g
 |-  ( -. M e. _V -> K = (/) )
38 37 orcd
 |-  ( -. M e. _V -> ( K = (/) \/ B = (/) ) )
39 0mpo0
 |-  ( ( K = (/) \/ B = (/) ) -> ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) = (/) )
40 38 39 syl
 |-  ( -. M e. _V -> ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) = (/) )
41 32 40 eqtr4d
 |-  ( -. M e. _V -> ( .s ` ( MEndo ` M ) ) = ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) ) )
42 27 41 pm2.61i
 |-  ( .s ` ( MEndo ` M ) ) = ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) )
43 7 42 eqtri
 |-  ( .s ` A ) = ( x e. K , y e. B |-> ( ( E X. { x } ) oF .x. y ) )