Metamath Proof Explorer


Theorem lcdvbase

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

Ref Expression
Hypotheses lcdvbase.h 𝐻 = ( LHyp ‘ 𝐾 )
lcdvbase.o = ( ( ocH ‘ 𝐾 ) ‘ 𝑊 )
lcdvbase.c 𝐶 = ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 )
lcdvbase.v 𝑉 = ( Base ‘ 𝐶 )
lcdvbase.u 𝑈 = ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 )
lcdvbase.f 𝐹 = ( LFnl ‘ 𝑈 )
lcdvbase.l 𝐿 = ( LKer ‘ 𝑈 )
lcdvbase.b 𝐵 = { 𝑓𝐹 ∣ ( ‘ ( ‘ ( 𝐿𝑓 ) ) ) = ( 𝐿𝑓 ) }
lcdvbase.k ( 𝜑 → ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) )
Assertion lcdvbase ( 𝜑𝑉 = 𝐵 )

Proof

Step Hyp Ref Expression
1 lcdvbase.h 𝐻 = ( LHyp ‘ 𝐾 )
2 lcdvbase.o = ( ( ocH ‘ 𝐾 ) ‘ 𝑊 )
3 lcdvbase.c 𝐶 = ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 )
4 lcdvbase.v 𝑉 = ( Base ‘ 𝐶 )
5 lcdvbase.u 𝑈 = ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 )
6 lcdvbase.f 𝐹 = ( LFnl ‘ 𝑈 )
7 lcdvbase.l 𝐿 = ( LKer ‘ 𝑈 )
8 lcdvbase.b 𝐵 = { 𝑓𝐹 ∣ ( ‘ ( ‘ ( 𝐿𝑓 ) ) ) = ( 𝐿𝑓 ) }
9 lcdvbase.k ( 𝜑 → ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) )
10 eqid ( LDual ‘ 𝑈 ) = ( LDual ‘ 𝑈 )
11 1 2 3 5 6 7 10 9 8 lcdval2 ( 𝜑𝐶 = ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) )
12 11 fveq2d ( 𝜑 → ( Base ‘ 𝐶 ) = ( Base ‘ ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) ) )
13 4 12 syl5eq ( 𝜑𝑉 = ( Base ‘ ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) ) )
14 ssrab2 { 𝑓𝐹 ∣ ( ‘ ( ‘ ( 𝐿𝑓 ) ) ) = ( 𝐿𝑓 ) } ⊆ 𝐹
15 8 14 eqsstri 𝐵𝐹
16 eqid ( Base ‘ ( LDual ‘ 𝑈 ) ) = ( Base ‘ ( LDual ‘ 𝑈 ) )
17 1 5 9 dvhlmod ( 𝜑𝑈 ∈ LMod )
18 6 10 16 17 ldualvbase ( 𝜑 → ( Base ‘ ( LDual ‘ 𝑈 ) ) = 𝐹 )
19 15 18 sseqtrrid ( 𝜑𝐵 ⊆ ( Base ‘ ( LDual ‘ 𝑈 ) ) )
20 eqid ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) = ( ( LDual ‘ 𝑈 ) ↾s 𝐵 )
21 20 16 ressbas2 ( 𝐵 ⊆ ( Base ‘ ( LDual ‘ 𝑈 ) ) → 𝐵 = ( Base ‘ ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) ) )
22 19 21 syl ( 𝜑𝐵 = ( Base ‘ ( ( LDual ‘ 𝑈 ) ↾s 𝐵 ) ) )
23 13 22 eqtr4d ( 𝜑𝑉 = 𝐵 )