Metamath Proof Explorer


Theorem srasca

Description: The set of scalars of a subring algebra. (Contributed by Stefan O'Rear, 27-Nov-2014) (Revised by Mario Carneiro, 4-Oct-2015) (Revised by Thierry Arnoux, 16-Jun-2019) (Proof shortened by AV, 12-Nov-2024)

Ref Expression
Hypotheses srapart.a ⊢ φ → A = subringAlg ⁡ W ⁡ S
srapart.s ⊢ φ → S ⊆ Base W
Assertion srasca ⊢ φ → W ↾ 𝑠 S = Scalar ⁡ A

Proof

Step Hyp Ref Expression
1 srapart.a ⊢ φ → A = subringAlg ⁡ W ⁡ S
2 srapart.s ⊢ φ → S ⊆ Base W
3 scaid ⊢ Scalar = Slot Scalar ⁡ ndx
4 vscandxnscandx ⊢ ⋅ ndx ≠ Scalar ⁡ ndx
5 4 necomi ⊢ Scalar ⁡ ndx ≠ ⋅ ndx
6 3 5 setsnid ⊢ Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W
7 slotsdifipndx ⊢ ⋅ ndx ≠ ⋅ 𝑖 ⁡ ndx ∧ Scalar ⁡ ndx ≠ ⋅ 𝑖 ⁡ ndx
8 7 simpri ⊢ Scalar ⁡ ndx ≠ ⋅ 𝑖 ⁡ ndx
9 3 8 setsnid ⊢ Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
10 6 9 eqtri ⊢ Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
11 ovexd ⊢ φ → W ↾ 𝑠 S ∈ V
12 3 setsid ⊢ W ∈ V ∧ W ↾ 𝑠 S ∈ V → W ↾ 𝑠 S = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S
13 11 12 sylan2 ⊢ W ∈ V ∧ φ → W ↾ 𝑠 S = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S
14 1 adantl ⊢ W ∈ V ∧ φ → A = subringAlg ⁡ W ⁡ S
15 sraval ⊢ W ∈ V ∧ S ⊆ Base W → subringAlg ⁡ W ⁡ S = W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
16 2 15 sylan2 ⊢ W ∈ V ∧ φ → subringAlg ⁡ W ⁡ S = W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
17 14 16 eqtrd ⊢ W ∈ V ∧ φ → A = W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
18 17 fveq2d ⊢ W ∈ V ∧ φ → Scalar ⁡ A = Scalar ⁡ W sSet Scalar ⁡ ndx W ↾ 𝑠 S sSet ⋅ ndx ⋅ W sSet ⋅ 𝑖 ⁡ ndx ⋅ W
19 10 13 18 3eqtr4a ⊢ W ∈ V ∧ φ → W ↾ 𝑠 S = Scalar ⁡ A
20 3 str0 ⊢ ∅ = Scalar ⁡ ∅
21 reldmress ⊢ Rel ⁡ dom ⁡ ↾ 𝑠
22 21 ovprc1 ⊢ ¬ W ∈ V → W ↾ 𝑠 S = ∅
23 22 adantr ⊢ ¬ W ∈ V ∧ φ → W ↾ 𝑠 S = ∅
24 fv2prc ⊢ ¬ W ∈ V → subringAlg ⁡ W ⁡ S = ∅
25 1 24 sylan9eqr ⊢ ¬ W ∈ V ∧ φ → A = ∅
26 25 fveq2d ⊢ ¬ W ∈ V ∧ φ → Scalar ⁡ A = Scalar ⁡ ∅
27 20 23 26 3eqtr4a ⊢ ¬ W ∈ V ∧ φ → W ↾ 𝑠 S = Scalar ⁡ A
28 19 27 pm2.61ian ⊢ φ → W ↾ 𝑠 S = Scalar ⁡ A