set cR = center R;
set ccR = the carrier of (center R);
set cs = centralizer s;
set ccs = the carrier of (centralizer s);
set lm = the multF of R | [: the carrier of (center R), the carrier of (centralizer s):];
A1:
the carrier of (center R) c= the carrier of R
by Th17;
A2:
the carrier of (centralizer s) c= the carrier of R
by Th24;
A3:
dom the multF of R = [: the carrier of R, the carrier of R:]
by FUNCT_2:def 1;
[: the carrier of (center R), the carrier of (centralizer s):] c= [: the carrier of R, the carrier of R:]
then A4:
dom ( the multF of R | [: the carrier of (center R), the carrier of (centralizer s):]) = [: the carrier of (center R), the carrier of (centralizer s):]
by A3, RELAT_1:62;
now let x be
set ;
( x in [: the carrier of (center R), the carrier of (centralizer s):] implies ( the multF of R | [: the carrier of (center R), the carrier of (centralizer s):]) . x in the carrier of (centralizer s) )assume A5:
x in [: the carrier of (center R), the carrier of (centralizer s):]
;
( the multF of R | [: the carrier of (center R), the carrier of (centralizer s):]) . x in the carrier of (centralizer s)then consider x1,
x2 being
set such that A6:
x1 in the
carrier of
(center R)
and A7:
x2 in the
carrier of
(centralizer s)
and A8:
x = [x1,x2]
by ZFMISC_1:def 2;
reconsider x1 =
x1 as
Element of
R by A1, A6;
reconsider x2 =
x2 as
Element of
R by A2, A7;
( the multF of R | [: the carrier of (center R), the carrier of (centralizer s):]) . x = x1 * x2
by A5, A8, FUNCT_1:49;
hence
( the multF of R | [: the carrier of (center R), the carrier of (centralizer s):]) . x in the
carrier of
(centralizer s)
by A6, A7, Th27;
verum end;
then reconsider lm = the multF of R | [: the carrier of (center R), the carrier of (centralizer s):] as Function of [: the carrier of (center R), the carrier of (centralizer s):], the carrier of (centralizer s) by A4, FUNCT_2:3;
set Vos = VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #);
set cV = the carrier of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #);
set aV = the addF of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #);
A9:
( VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is vector-distributive & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-distributive & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-associative & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-unital )
proof
A10:
the
multF of
(center R) = the
multF of
R || the
carrier of
(center R)
by Def4;
A11:
the
addF of
(center R) = the
addF of
R || the
carrier of
(center R)
by Def4;
A12:
the
addF of
(centralizer s) = the
addF of
R || the
carrier of
(centralizer s)
by Def5;
thus
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #) is
vector-distributive
( VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-distributive & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-associative & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-unital )proof
let x be
Element of the
carrier of
(center R);
VECTSP_1:def 14 for b1, b2 being Element of the carrier of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) holds x * (b1 + b2) = (x * b1) + (x * b2)let v,
w be
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #);
x * (v + w) = (x * v) + (x * w)
x in the
carrier of
(center R)
;
then reconsider xx =
x as
Element of
R by A1;
A13:
v in the
carrier of
(centralizer s)
;
w in the
carrier of
(centralizer s)
;
then reconsider vv =
v,
ww =
w as
Element of
R by A2, A13;
A14:
[x,w] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A15:
[x,(v + w)] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A16:
[v,w] in [: the carrier of (centralizer s), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A17:
[x,v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A18:
[(x * v),(x * w)] in [: the carrier of (centralizer s), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
thus x * (v + w) =
the
multF of
R . [x,( the addF of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) . [v,w])]
by A15, FUNCT_1:49
.=
xx * (vv + ww)
by A12, A16, FUNCT_1:49
.=
(xx * vv) + (xx * ww)
by VECTSP_1:def 2
.=
the
addF of
R . [(x * v),( the multF of R . [xx,ww])]
by A17, FUNCT_1:49
.=
the
addF of
R . [(x * v),(x * w)]
by A14, FUNCT_1:49
.=
(x * v) + (x * w)
by A12, A18, FUNCT_1:49
;
verum
end;
thus
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #) is
scalar-distributive
( VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-associative & VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-unital )proof
let x,
y be
Element of the
carrier of
(center R);
VECTSP_1:def 15 for b1 being Element of the carrier of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) holds (x + y) * b1 = (x * b1) + (y * b1)let v be
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #);
(x + y) * v = (x * v) + (y * v)
A19:
x in the
carrier of
(center R)
;
y in the
carrier of
(center R)
;
then reconsider xx =
x,
yy =
y as
Element of
R by A1, A19;
v in the
carrier of
(centralizer s)
;
then reconsider vv =
v as
Element of
R by A2;
A20:
[y,v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A21:
[x,v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A22:
[(x + y),v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A23:
[x,y] in [: the carrier of (center R), the carrier of (center R):]
by ZFMISC_1:def 2;
A24:
[(x * v),(y * v)] in [: the carrier of (centralizer s), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
thus (x + y) * v =
the
multF of
R . [( the addF of (center R) . [x,y]),vv]
by A22, FUNCT_1:49
.=
(xx + yy) * vv
by A11, A23, FUNCT_1:49
.=
(xx * vv) + (yy * vv)
by VECTSP_1:def 3
.=
the
addF of
R . [(x * v),( the multF of R . [yy,vv])]
by A21, FUNCT_1:49
.=
the
addF of
R . [(x * v),(lm . (y,v))]
by A20, FUNCT_1:49
.=
(x * v) + (y * v)
by A12, A24, FUNCT_1:49
;
verum
end;
thus
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #) is
scalar-associative
VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is scalar-unital proof
let x,
y be
Element of the
carrier of
(center R);
VECTSP_1:def 16 for b1 being Element of the carrier of VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) holds (x * y) * b1 = x * (y * b1)let v be
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #);
(x * y) * v = x * (y * v)
A25:
x in the
carrier of
(center R)
;
y in the
carrier of
(center R)
;
then reconsider xx =
x,
yy =
y as
Element of
R by A1, A25;
v in the
carrier of
(centralizer s)
;
then reconsider vv =
v as
Element of
R by A2;
A26:
[x,(y * v)] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A27:
[y,v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A28:
[(x * y),v] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
A29:
[x,y] in [: the carrier of (center R), the carrier of (center R):]
by ZFMISC_1:def 2;
thus (x * y) * v =
the
multF of
R . [( the multF of (center R) . (x,y)),vv]
by A28, FUNCT_1:49
.=
(xx * yy) * vv
by A10, A29, FUNCT_1:49
.=
xx * (yy * vv)
by GROUP_1:def 3
.=
the
multF of
R . [xx,(lm . (y,v))]
by A27, FUNCT_1:49
.=
x * (y * v)
by A26, FUNCT_1:49
;
verum
end;
let v be
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #);
VECTSP_1:def 17 (1. (center R)) * v = v
v in the
carrier of
(centralizer s)
;
then reconsider vv =
v as
Element of
R by A2;
1_ R in center R
by Th20;
then
1_ R in the
carrier of
(center R)
by STRUCT_0:def 5;
then A30:
[(1_ R),vv] in [: the carrier of (center R), the carrier of (centralizer s):]
by ZFMISC_1:def 2;
thus (1. (center R)) * v =
lm . (
(1. R),
vv)
by Def4
.=
(1. R) * vv
by A30, FUNCT_1:49
.=
v
by VECTSP_1:def 8
;
verum
end;
A31:
VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is add-associative
A32:
VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is right_zeroed
A33:
VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is right_complementable
proof
let v be
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #);
ALGSTR_0:def 16 v is right_complementable
reconsider vv =
v as
Element of the
carrier of
(centralizer s) ;
consider ww being
Element of the
carrier of
(centralizer s) such that A34:
vv + ww = 0. (centralizer s)
by ALGSTR_0:def 11;
reconsider w =
ww as
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #) ;
v + w = 0. VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #)
by A34;
hence
ex
w being
Element of the
carrier of
VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #) st
v + w = 0. VectSpStr(# the
carrier of
(centralizer s), the
addF of
(centralizer s),
(0. (centralizer s)),
lm #)
;
ALGSTR_0:def 11 verum
end;
VectSpStr(# the carrier of (centralizer s), the addF of (centralizer s),(0. (centralizer s)),lm #) is Abelian
hence
ex b1 being strict VectSp of center R st
( addLoopStr(# the carrier of b1, the addF of b1, the ZeroF of b1 #) = addLoopStr(# the carrier of (centralizer s), the addF of (centralizer s), the ZeroF of (centralizer s) #) & the lmult of b1 = the multF of R | [: the carrier of (center R), the carrier of (centralizer s):] )
by A9, A31, A32, A33; verum