Metamath Proof Explorer


Theorem lcdlss

Description: Subspaces of a dual vector space of functionals with closed kernels. (Contributed by NM, 13-Mar-2015)

Ref Expression
Hypotheses lcdlss.h
|- H = ( LHyp ` K )
lcdlss.o
|- O = ( ( ocH ` K ) ` W )
lcdlss.c
|- C = ( ( LCDual ` K ) ` W )
lcdlss.s
|- S = ( LSubSp ` C )
lcdlss.u
|- U = ( ( DVecH ` K ) ` W )
lcdlss.f
|- F = ( LFnl ` U )
lcdlss.l
|- L = ( LKer ` U )
lcdlss.d
|- D = ( LDual ` U )
lcdlss.t
|- T = ( LSubSp ` D )
lcdlss.b
|- B = { f e. F | ( O ` ( O ` ( L ` f ) ) ) = ( L ` f ) }
lcdlss.k
|- ( ph -> ( K e. HL /\ W e. H ) )
Assertion lcdlss
|- ( ph -> S = ( T i^i ~P B ) )

Proof

Step Hyp Ref Expression
1 lcdlss.h
 |-  H = ( LHyp ` K )
2 lcdlss.o
 |-  O = ( ( ocH ` K ) ` W )
3 lcdlss.c
 |-  C = ( ( LCDual ` K ) ` W )
4 lcdlss.s
 |-  S = ( LSubSp ` C )
5 lcdlss.u
 |-  U = ( ( DVecH ` K ) ` W )
6 lcdlss.f
 |-  F = ( LFnl ` U )
7 lcdlss.l
 |-  L = ( LKer ` U )
8 lcdlss.d
 |-  D = ( LDual ` U )
9 lcdlss.t
 |-  T = ( LSubSp ` D )
10 lcdlss.b
 |-  B = { f e. F | ( O ` ( O ` ( L ` f ) ) ) = ( L ` f ) }
11 lcdlss.k
 |-  ( ph -> ( K e. HL /\ W e. H ) )
12 1 2 3 5 6 7 8 11 10 lcdval2
 |-  ( ph -> C = ( D |`s B ) )
13 12 fveq2d
 |-  ( ph -> ( LSubSp ` C ) = ( LSubSp ` ( D |`s B ) ) )
14 4 13 eqtrid
 |-  ( ph -> S = ( LSubSp ` ( D |`s B ) ) )
15 14 eleq2d
 |-  ( ph -> ( u e. S <-> u e. ( LSubSp ` ( D |`s B ) ) ) )
16 1 5 11 dvhlmod
 |-  ( ph -> U e. LMod )
17 8 16 lduallmod
 |-  ( ph -> D e. LMod )
18 1 5 2 6 7 8 9 10 11 lclkr
 |-  ( ph -> B e. T )
19 eqid
 |-  ( D |`s B ) = ( D |`s B )
20 eqid
 |-  ( LSubSp ` ( D |`s B ) ) = ( LSubSp ` ( D |`s B ) )
21 19 9 20 lsslss
 |-  ( ( D e. LMod /\ B e. T ) -> ( u e. ( LSubSp ` ( D |`s B ) ) <-> ( u e. T /\ u C_ B ) ) )
22 17 18 21 syl2anc
 |-  ( ph -> ( u e. ( LSubSp ` ( D |`s B ) ) <-> ( u e. T /\ u C_ B ) ) )
23 15 22 bitrd
 |-  ( ph -> ( u e. S <-> ( u e. T /\ u C_ B ) ) )
24 elin
 |-  ( u e. ( T i^i ~P B ) <-> ( u e. T /\ u e. ~P B ) )
25 velpw
 |-  ( u e. ~P B <-> u C_ B )
26 25 anbi2i
 |-  ( ( u e. T /\ u e. ~P B ) <-> ( u e. T /\ u C_ B ) )
27 24 26 bitr2i
 |-  ( ( u e. T /\ u C_ B ) <-> u e. ( T i^i ~P B ) )
28 23 27 bitrdi
 |-  ( ph -> ( u e. S <-> u e. ( T i^i ~P B ) ) )
29 28 eqrdv
 |-  ( ph -> S = ( T i^i ~P B ) )