Metamath Proof Explorer


Definition df-ldual

Description: Define the (left) dual of a left vector space (or module) in which the vectors are functionals. In many texts, this is defined as a right vector space, but by reversing the multiplication we achieve a left vector space, as is done in definition of dual vector space in Holland95 p. 218. This allows to reuse our existing collection of left vector space theorems. The restriction on oF ( +gv ) allows it to be a set; see ofmres . Note the operation reversal in the scalar product to allow to use the original scalar ring instead of the oppR ring, for convenience. (Contributed by NM, 18-Oct-2014)

Ref Expression
Assertion df-ldual LDual=vVBasendxLFnlv+ndxf+ScalarvLFnlv×LFnlvScalarndxopprScalarvndxkBaseScalarv,fLFnlvfScalarvfBasev×k

Detailed syntax breakdown

Step Hyp Ref Expression
0 cld classLDual
1 vv setvarv
2 cvv classV
3 cbs classBase
4 cnx classndx
5 4 3 cfv classBasendx
6 clfn classLFnl
7 1 cv setvarv
8 7 6 cfv classLFnlv
9 5 8 cop classBasendxLFnlv
10 cplusg class+𝑔
11 4 10 cfv class+ndx
12 csca classScalar
13 7 12 cfv classScalarv
14 13 10 cfv class+Scalarv
15 14 cof classf+Scalarv
16 8 8 cxp classLFnlv×LFnlv
17 15 16 cres classf+ScalarvLFnlv×LFnlv
18 11 17 cop class+ndxf+ScalarvLFnlv×LFnlv
19 4 12 cfv classScalarndx
20 coppr classoppr
21 13 20 cfv classopprScalarv
22 19 21 cop classScalarndxopprScalarv
23 9 18 22 ctp classBasendxLFnlv+ndxf+ScalarvLFnlv×LFnlvScalarndxopprScalarv
24 cvsca class𝑠
25 4 24 cfv classndx
26 vk setvark
27 13 3 cfv classBaseScalarv
28 vf setvarf
29 28 cv setvarf
30 cmulr class𝑟
31 13 30 cfv classScalarv
32 31 cof classfScalarv
33 7 3 cfv classBasev
34 26 cv setvark
35 34 csn classk
36 33 35 cxp classBasev×k
37 29 36 32 co classfScalarvfBasev×k
38 26 28 27 8 37 cmpo classkBaseScalarv,fLFnlvfScalarvfBasev×k
39 25 38 cop classndxkBaseScalarv,fLFnlvfScalarvfBasev×k
40 39 csn classndxkBaseScalarv,fLFnlvfScalarvfBasev×k
41 23 40 cun classBasendxLFnlv+ndxf+ScalarvLFnlv×LFnlvScalarndxopprScalarvndxkBaseScalarv,fLFnlvfScalarvfBasev×k
42 1 2 41 cmpt classvVBasendxLFnlv+ndxf+ScalarvLFnlv×LFnlvScalarndxopprScalarvndxkBaseScalarv,fLFnlvfScalarvfBasev×k
43 0 42 wceq wffLDual=vVBasendxLFnlv+ndxf+ScalarvLFnlv×LFnlvScalarndxopprScalarvndxkBaseScalarv,fLFnlvfScalarvfBasev×k