Metamath Proof Explorer


Theorem algextdeglem2

Description: Lemma for algextdeg . Both the ring of polynomials P and the field L generated by K and the algebraic element A can be considered as modules over the elements of F . Then, the evaluation map G , mapping polynomials to their evaluation at A , is a module homomorphism between those modules. (Contributed by Thierry Arnoux, 2-Apr-2025)

Ref Expression
Hypotheses algextdeg.k 𝐾 = ( 𝐸s 𝐹 )
algextdeg.l 𝐿 = ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
algextdeg.d 𝐷 = ( deg1𝐸 )
algextdeg.m 𝑀 = ( 𝐸 minPoly 𝐹 )
algextdeg.f ( 𝜑𝐸 ∈ Field )
algextdeg.e ( 𝜑𝐹 ∈ ( SubDRing ‘ 𝐸 ) )
algextdeg.a ( 𝜑𝐴 ∈ ( 𝐸 IntgRing 𝐹 ) )
algextdeglem.o 𝑂 = ( 𝐸 evalSub1 𝐹 )
algextdeglem.y 𝑃 = ( Poly1𝐾 )
algextdeglem.u 𝑈 = ( Base ‘ 𝑃 )
algextdeglem.g 𝐺 = ( 𝑝𝑈 ↦ ( ( 𝑂𝑝 ) ‘ 𝐴 ) )
algextdeglem.n 𝑁 = ( 𝑥𝑈 ↦ [ 𝑥 ] ( 𝑃 ~QG 𝑍 ) )
algextdeglem.z 𝑍 = ( 𝐺 “ { ( 0g𝐿 ) } )
algextdeglem.q 𝑄 = ( 𝑃 /s ( 𝑃 ~QG 𝑍 ) )
algextdeglem.j 𝐽 = ( 𝑝 ∈ ( Base ‘ 𝑄 ) ↦ ( 𝐺𝑝 ) )
Assertion algextdeglem2 ( 𝜑𝐺 ∈ ( 𝑃 LMHom ( ( subringAlg ‘ 𝐿 ) ‘ 𝐹 ) ) )

Proof

Step Hyp Ref Expression
1 algextdeg.k 𝐾 = ( 𝐸s 𝐹 )
2 algextdeg.l 𝐿 = ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
3 algextdeg.d 𝐷 = ( deg1𝐸 )
4 algextdeg.m 𝑀 = ( 𝐸 minPoly 𝐹 )
5 algextdeg.f ( 𝜑𝐸 ∈ Field )
6 algextdeg.e ( 𝜑𝐹 ∈ ( SubDRing ‘ 𝐸 ) )
7 algextdeg.a ( 𝜑𝐴 ∈ ( 𝐸 IntgRing 𝐹 ) )
8 algextdeglem.o 𝑂 = ( 𝐸 evalSub1 𝐹 )
9 algextdeglem.y 𝑃 = ( Poly1𝐾 )
10 algextdeglem.u 𝑈 = ( Base ‘ 𝑃 )
11 algextdeglem.g 𝐺 = ( 𝑝𝑈 ↦ ( ( 𝑂𝑝 ) ‘ 𝐴 ) )
12 algextdeglem.n 𝑁 = ( 𝑥𝑈 ↦ [ 𝑥 ] ( 𝑃 ~QG 𝑍 ) )
13 algextdeglem.z 𝑍 = ( 𝐺 “ { ( 0g𝐿 ) } )
14 algextdeglem.q 𝑄 = ( 𝑃 /s ( 𝑃 ~QG 𝑍 ) )
15 algextdeglem.j 𝐽 = ( 𝑝 ∈ ( Base ‘ 𝑄 ) ↦ ( 𝐺𝑝 ) )
16 issdrg ( 𝐹 ∈ ( SubDRing ‘ 𝐸 ) ↔ ( 𝐸 ∈ DivRing ∧ 𝐹 ∈ ( SubRing ‘ 𝐸 ) ∧ ( 𝐸s 𝐹 ) ∈ DivRing ) )
17 6 16 sylib ( 𝜑 → ( 𝐸 ∈ DivRing ∧ 𝐹 ∈ ( SubRing ‘ 𝐸 ) ∧ ( 𝐸s 𝐹 ) ∈ DivRing ) )
18 17 simp2d ( 𝜑𝐹 ∈ ( SubRing ‘ 𝐸 ) )
19 eqid ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) = ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 )
20 19 sralmod ( 𝐹 ∈ ( SubRing ‘ 𝐸 ) → ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ∈ LMod )
21 18 20 syl ( 𝜑 → ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ∈ LMod )
22 eqid ( Base ‘ 𝐸 ) = ( Base ‘ 𝐸 )
23 eqid ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) = ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
24 5 flddrngd ( 𝜑𝐸 ∈ DivRing )
25 subrgsubg ( 𝐹 ∈ ( SubRing ‘ 𝐸 ) → 𝐹 ∈ ( SubGrp ‘ 𝐸 ) )
26 22 subgss ( 𝐹 ∈ ( SubGrp ‘ 𝐸 ) → 𝐹 ⊆ ( Base ‘ 𝐸 ) )
27 18 25 26 3syl ( 𝜑𝐹 ⊆ ( Base ‘ 𝐸 ) )
28 eqid ( 0g𝐸 ) = ( 0g𝐸 )
29 5 fldcrngd ( 𝜑𝐸 ∈ CRing )
30 8 1 22 28 29 18 irngssv ( 𝜑 → ( 𝐸 IntgRing 𝐹 ) ⊆ ( Base ‘ 𝐸 ) )
31 30 7 sseldd ( 𝜑𝐴 ∈ ( Base ‘ 𝐸 ) )
32 31 snssd ( 𝜑 → { 𝐴 } ⊆ ( Base ‘ 𝐸 ) )
33 27 32 unssd ( 𝜑 → ( 𝐹 ∪ { 𝐴 } ) ⊆ ( Base ‘ 𝐸 ) )
34 22 24 33 fldgensdrg ( 𝜑 → ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubDRing ‘ 𝐸 ) )
35 issdrg ( ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubDRing ‘ 𝐸 ) ↔ ( 𝐸 ∈ DivRing ∧ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubRing ‘ 𝐸 ) ∧ ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ∈ DivRing ) )
36 34 35 sylib ( 𝜑 → ( 𝐸 ∈ DivRing ∧ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubRing ‘ 𝐸 ) ∧ ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ∈ DivRing ) )
37 36 simp2d ( 𝜑 → ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubRing ‘ 𝐸 ) )
38 22 24 33 fldgenssid ( 𝜑 → ( 𝐹 ∪ { 𝐴 } ) ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
39 38 unssad ( 𝜑𝐹 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
40 23 subsubrg ( ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubRing ‘ 𝐸 ) → ( 𝐹 ∈ ( SubRing ‘ ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) ↔ ( 𝐹 ∈ ( SubRing ‘ 𝐸 ) ∧ 𝐹 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
41 40 biimpar ( ( ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( SubRing ‘ 𝐸 ) ∧ ( 𝐹 ∈ ( SubRing ‘ 𝐸 ) ∧ 𝐹 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) → 𝐹 ∈ ( SubRing ‘ ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
42 37 18 39 41 syl12anc ( 𝜑𝐹 ∈ ( SubRing ‘ ( 𝐸s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
43 19 22 23 37 42 lsssra ( 𝜑 → ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( LSubSp ‘ ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) )
44 1 fveq2i ( Poly1𝐾 ) = ( Poly1 ‘ ( 𝐸s 𝐹 ) )
45 9 44 eqtri 𝑃 = ( Poly1 ‘ ( 𝐸s 𝐹 ) )
46 5 adantr ( ( 𝜑𝑝𝑈 ) → 𝐸 ∈ Field )
47 6 adantr ( ( 𝜑𝑝𝑈 ) → 𝐹 ∈ ( SubDRing ‘ 𝐸 ) )
48 31 adantr ( ( 𝜑𝑝𝑈 ) → 𝐴 ∈ ( Base ‘ 𝐸 ) )
49 simpr ( ( 𝜑𝑝𝑈 ) → 𝑝𝑈 )
50 22 8 45 10 46 47 48 49 evls1fldgencl ( ( 𝜑𝑝𝑈 ) → ( ( 𝑂𝑝 ) ‘ 𝐴 ) ∈ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
51 50 ralrimiva ( 𝜑 → ∀ 𝑝𝑈 ( ( 𝑂𝑝 ) ‘ 𝐴 ) ∈ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
52 11 rnmptss ( ∀ 𝑝𝑈 ( ( 𝑂𝑝 ) ‘ 𝐴 ) ∈ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) → ran 𝐺 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
53 51 52 syl ( 𝜑 → ran 𝐺 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
54 8 45 22 10 29 18 31 11 19 evls1maplmhm ( 𝜑𝐺 ∈ ( 𝑃 LMHom ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) )
55 eqid ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) = ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) )
56 eqid ( LSubSp ‘ ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) = ( LSubSp ‘ ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) )
57 55 56 reslmhm2b ( ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ∈ LMod ∧ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( LSubSp ‘ ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) ∧ ran 𝐺 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) → ( 𝐺 ∈ ( 𝑃 LMHom ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) ↔ 𝐺 ∈ ( 𝑃 LMHom ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) ) )
58 57 biimpa ( ( ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ∈ LMod ∧ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ∈ ( LSubSp ‘ ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) ∧ ran 𝐺 ⊆ ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ∧ 𝐺 ∈ ( 𝑃 LMHom ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ) ) → 𝐺 ∈ ( 𝑃 LMHom ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
59 21 43 53 54 58 syl31anc ( 𝜑𝐺 ∈ ( 𝑃 LMHom ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
60 22 24 33 fldgenssv ( 𝜑 → ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ⊆ ( Base ‘ 𝐸 ) )
61 22 2 60 39 5 resssra ( 𝜑 → ( ( subringAlg ‘ 𝐿 ) ‘ 𝐹 ) = ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) )
62 61 oveq2d ( 𝜑 → ( 𝑃 LMHom ( ( subringAlg ‘ 𝐿 ) ‘ 𝐹 ) ) = ( 𝑃 LMHom ( ( ( subringAlg ‘ 𝐸 ) ‘ 𝐹 ) ↾s ( 𝐸 fldGen ( 𝐹 ∪ { 𝐴 } ) ) ) ) )
63 59 62 eleqtrrd ( 𝜑𝐺 ∈ ( 𝑃 LMHom ( ( subringAlg ‘ 𝐿 ) ‘ 𝐹 ) ) )