P. 231 of Theorem List - Metamath Proof Explorer

Type

Label

Description

Statement

Theorem

decpmatmulsumfsupp 23001*

Lemma 0 for pm2mpmhm 23048. (Contributed by AV, 21-Oct-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ · = (._r‘𝐴)    &   ⊢ 0 = (0_g‘𝐴)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑙 ∈ ℕ₀ ↦ (𝐴 Σ_g (𝑘 ∈ (0...𝑙) ↦ ((𝑥 decompPMat 𝑘) · (𝑦 decompPMat (𝑙 − 𝑘)))))) finSupp 0 )

Theorem

pmatcollpw1lem1 23002*

Lemma 1 for pmatcollpw1 23004. (Contributed by AV, 28-Sep-2019.) (Revised by AV, 3-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ × = ( ·_𝑠 ‘𝑃)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ 𝐼 ∈ 𝑁 ∧ 𝐽 ∈ 𝑁) → (𝑛 ∈ ℕ₀ ↦ ((𝐼(𝑀 decompPMat 𝑛)𝐽) × (𝑛 ↑ 𝑋))) finSupp (0_g‘𝑃))

Theorem

pmatcollpw1lem2 23003*

Lemma 2 for pmatcollpw1 23004: An entry of a polynomial matrix is the sum of the entries of the matrix consisting of the coefficients in the entries of the polynomial matrix multiplied with the corresponding power of the variable. (Contributed by AV, 25-Sep-2019.) (Revised by AV, 3-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ × = ( ·_𝑠 ‘𝑃)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ (𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁)) → (𝑎𝑀𝑏) = (𝑃 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑎(𝑀 decompPMat 𝑛)𝑏) × (𝑛 ↑ 𝑋)))))

Theorem

pmatcollpw1 23004*

Write a polynomial matrix as a matrix of sums of scaled monomials. (Contributed by AV, 29-Sep-2019.) (Revised by AV, 3-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ × = ( ·_𝑠 ‘𝑃)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → 𝑀 = (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑖(𝑀 decompPMat 𝑛)𝑗) × (𝑛 ↑ 𝑋))))))

Theorem

pmatcollpw2lem 23005*

Lemma for pmatcollpw2 23006. (Contributed by AV, 3-Oct-2019.) (Revised by AV, 3-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ × = ( ·_𝑠 ‘𝑃)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → (𝑛 ∈ ℕ₀ ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ ((𝑖(𝑀 decompPMat 𝑛)𝑗) × (𝑛 ↑ 𝑋)))) finSupp (0_g‘𝐶))

Theorem

pmatcollpw2 23006*

Write a polynomial matrix as a sum of matrices whose entries are products of variable powers and constant polynomials collecting like powers. (Contributed by AV, 3-Oct-2019.) (Revised by AV, 3-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ × = ( ·_𝑠 ‘𝑃)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → 𝑀 = (𝐶 Σ_g (𝑛 ∈ ℕ₀ ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ ((𝑖(𝑀 decompPMat 𝑛)𝑗) × (𝑛 ↑ 𝑋))))))

Theorem

monmatcollpw 23007

The matrix consisting of the coefficients in the polynomial entries of a polynomial matrix having scaled monomials with the same power as entries is the matrix of the coefficients of the monomials or a zero matrix. Generalization of decpmatid 22998 (but requires 𝑅 to be commutative!). (Contributed by AV, 11-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐾 = (Base‘𝐴)    &   ⊢ 0 = (0_g‘𝐴)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝐶)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐾 ∧ 𝐿 ∈ ℕ₀ ∧ 𝐼 ∈ ℕ₀)) → (((𝐿 ↑ 𝑋) · (𝑇‘𝑀)) decompPMat 𝐼) = if(𝐼 = 𝐿, 𝑀, 0 ))

Theorem

pmatcollpwlem 23008

Lemma for pmatcollpw 23009. (Contributed by AV, 26-Oct-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ 𝑛 ∈ ℕ₀) ∧ 𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁) → ((𝑎(𝑀 decompPMat 𝑛)𝑏)( ·_𝑠 ‘𝑃)(𝑛 ↑ 𝑋)) = (𝑎((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑀 decompPMat 𝑛)))𝑏))

Theorem

pmatcollpw 23009*

Write a polynomial matrix (over a commutative ring) as a sum of products of variable powers and constant matrices with scalar entries. (Contributed by AV, 26-Oct-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → 𝑀 = (𝐶 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑀 decompPMat 𝑛))))))

Theorem

pmatcollpwfi 23010*

Write a polynomial matrix (over a commutative ring) as a finite sum of products of variable powers and constant matrices with scalar entries. (Contributed by AV, 4-Nov-2019.) (Revised by AV, 4-Dec-2019.) (Proof shortened by AV, 3-Jul-2022.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → ∃𝑠 ∈ ℕ₀ 𝑀 = (𝐶 Σ_g (𝑛 ∈ (0...𝑠) ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑀 decompPMat 𝑛))))))

Theorem

pmatcollpw3lem 23011*

Lemma for pmatcollpw3 23012 and pmatcollpw3fi 23013: Write a polynomial matrix (over a commutative ring) as a sum of products of variable powers and constant matrices with scalar entries. (Contributed by AV, 8-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝐼 ⊆ ℕ₀ ∧ 𝐼 ≠ ∅)) → (𝑀 = (𝐶 Σ_g (𝑛 ∈ 𝐼 ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑀 decompPMat 𝑛))))) → ∃𝑓 ∈ (𝐷 ↑_m 𝐼)𝑀 = (𝐶 Σ_g (𝑛 ∈ 𝐼 ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛)))))))

Theorem

pmatcollpw3 23012*

Write a polynomial matrix (over a commutative ring) as a sum of products of variable powers and constant matrices with scalar entries. (Contributed by AV, 27-Oct-2019.) (Revised by AV, 4-Dec-2019.) (Proof shortened by AV, 8-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → ∃𝑓 ∈ (𝐷 ↑_m ℕ₀)𝑀 = (𝐶 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛))))))

Theorem

pmatcollpw3fi 23013*

Write a polynomial matrix (over a commutative ring) as a finite sum of products of variable powers and constant matrices with scalar entries. (Contributed by AV, 4-Nov-2019.) (Revised by AV, 4-Dec-2019.) (Proof shortened by AV, 8-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → ∃𝑠 ∈ ℕ₀ ∃𝑓 ∈ (𝐷 ↑_m (0...𝑠))𝑀 = (𝐶 Σ_g (𝑛 ∈ (0...𝑠) ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛))))))

Theorem

pmatcollpw3fi1lem1 23014*

Lemma 1 for pmatcollpw3fi1 23016. (Contributed by AV, 6-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    &   ⊢ 0 = (0_g‘𝐴)    &   ⊢ 𝐻 = (𝑙 ∈ (0...1) ↦ if(𝑙 = 0, (𝐺‘0), 0 ))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ 𝐺 ∈ (𝐷 ↑_m {0}) ∧ 𝑀 = (𝐶 Σ_g (𝑛 ∈ {0} ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝐺‘𝑛)))))) → 𝑀 = (𝐶 Σ_g (𝑛 ∈ (0...1) ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝐻‘𝑛))))))

Theorem

pmatcollpw3fi1lem2 23015*

Lemma 2 for pmatcollpw3fi1 23016. (Contributed by AV, 6-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → (∃𝑓 ∈ (𝐷 ↑_m {0})𝑀 = (𝐶 Σ_g (𝑛 ∈ {0} ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛))))) → ∃𝑠 ∈ ℕ ∃𝑓 ∈ (𝐷 ↑_m (0...𝑠))𝑀 = (𝐶 Σ_g (𝑛 ∈ (0...𝑠) ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛)))))))

Theorem

pmatcollpw3fi1 23016*

Write a polynomial matrix (over a commutative ring) as a finite sum of (at least two) products of variable powers and constant matrices with scalar entries. (Contributed by AV, 6-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → ∃𝑠 ∈ ℕ ∃𝑓 ∈ (𝐷 ↑_m (0...𝑠))𝑀 = (𝐶 Σ_g (𝑛 ∈ (0...𝑠) ↦ ((𝑛 ↑ 𝑋) ∗ (𝑇‘(𝑓‘𝑛))))))

Theorem

pmatcollpwscmatlem1 23017

Lemma 1 for pmatcollpwscmat 23019. (Contributed by AV, 2-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐾 = (Base‘𝑅)    &   ⊢ 𝐸 = (Base‘𝑃)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 1 = (1_r‘𝐶)    &   ⊢ 𝑀 = (𝑄 ∗ 1 )    ⇒   ⊢ ((((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝐿 ∈ ℕ₀ ∧ 𝑄 ∈ 𝐸)) ∧ (𝑎 ∈ 𝑁 ∧ 𝑏 ∈ 𝑁)) → (((coe₁‘(𝑎𝑀𝑏))‘𝐿)( ·_𝑠 ‘𝑃)(0(._g‘(mulGrp‘𝑃))(var₁‘𝑅))) = if(𝑎 = 𝑏, (𝑈‘((coe₁‘𝑄)‘𝐿)), (0_g‘𝑃)))

Theorem

pmatcollpwscmatlem2 23018

Lemma 2 for pmatcollpwscmat 23019. (Contributed by AV, 2-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐾 = (Base‘𝑅)    &   ⊢ 𝐸 = (Base‘𝑃)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 1 = (1_r‘𝐶)    &   ⊢ 𝑀 = (𝑄 ∗ 1 )    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝐿 ∈ ℕ₀ ∧ 𝑄 ∈ 𝐸)) → (𝑇‘(𝑀 decompPMat 𝐿)) = ((𝑈‘((coe₁‘𝑄)‘𝐿)) ∗ 1 ))

Theorem

pmatcollpwscmat 23019*

Write a scalar matrix over polynomials (over a commutative ring) as a sum of the product of variable powers and constant scalar matrices with scalar entries. (Contributed by AV, 2-Nov-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐶)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐷 = (Base‘𝐴)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐾 = (Base‘𝑅)    &   ⊢ 𝐸 = (Base‘𝑃)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 1 = (1_r‘𝐶)    &   ⊢ 𝑀 = (𝑄 ∗ 1 )    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑄 ∈ 𝐸) → 𝑀 = (𝐶 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛 ↑ 𝑋) ∗ ((𝑈‘((coe₁‘𝑄)‘𝑛)) ∗ 1 )))))

11.6.4  Ring isomorphism between polynomial matrices and polynomials over matrices

The main result of this section is Theorem pmmpric 23051, which shows that the ring of polynomial matrices and the ring of polynomials having matrices as coefficients (called "polynomials over matrices" in the following) are isomorphic:
(Poly₁‘(𝑁 Mat 𝑅)) ≃ (𝑁 Mat (Poly₁‘𝑅))

Or in a more common notation:
(𝑁 Mat (Poly₁‘𝑅)) corresponds to M(n, R[t]), the ring of n x n polynomial matrices over the ring R.
(Poly₁‘(𝑁 Mat 𝑅)) corresponds to M(n, R)[t], the polynomial ring over the ring of n x n matrices with entries in ring R.

𝑇 = (𝑚 ∈ 𝐵 ↦ (𝑄 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑚 decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋)))))

with 𝐵 = (Base‘(𝑁 Mat (Poly₁‘𝑅))) and (𝑚 decompPMat 𝑘) = (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ ((coe₁ ( i m j ) ) 𝑘))) is an isomorphism between these rings:

𝑇:𝐵–1-1-onto→𝐿 with 𝐿 = (Base‘(Poly₁‘(𝑁 Mat 𝑅))) (see pm2mpf1o 23043 and pm2mprngiso 23050), and

𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁ p ) 𝑘)𝑗) · (𝑘𝐸𝑌))))))

is the corresponding inverse function:

(𝑇‘(𝐼‘𝑂)) = 𝑂) (see mp2pm2mp 23039).

In this section, the following conventions are mostly used:

• 𝑅 is a (unital) ring (see df-ring 20377)
• 𝑃 = (Poly₁‘𝑅) is the polynomial algebra over (the ring) 𝑅 (see df-ply1 22410)
  • 𝐾 = (Base‘𝑃) is its base set (see df-base 17305)
  • 𝑌 = (var₁‘𝑅) is its variable (see df-vr1 22409)
  • · = ( ·_𝑠 ‘𝑃) is its scalar multiplication (see df-vsca 17362 or lmodvscl 21065)
  • 𝐸 = (._g‘(mulGrp‘𝑃)) is its exponentiation (see df-mulg 19194)
• 𝐴 = (𝑁 Mat 𝑅) is the algebra of N x N matrices over (the ring) 𝑅 (see df-mat 22633)
• 𝐶 = (𝑁 Mat 𝑃) is the algebra of N x N matrices over (the polynomial ring) 𝑃.
  • 𝐵 = (Base‘𝐶) is its base set
  • 𝑀 ∈ 𝐵 is a concrete polynomial matrix
• 𝑄 = (Poly₁‘𝐴) is the polynomial algebra over (the matrix ring) 𝐴.
  • 𝐿 = (Base‘𝑄) is its base set
  • 𝑂 ∈ 𝐿 is a concrete polynomial with matrix coefficients
  • 𝑋 = (var₁‘𝐴) is its variable
  • ∗ = ( ·_𝑠 ‘𝑄) is its scalar multiplication
  • ↑ = (._g‘(mulGrp‘𝑄)) is its exponentiation

Syntax

cpm2mp 23020

Extend class notation with the transformation of a polynomial matrix into a polynomial over matrices.

class pMatToMatPoly

Definition

df-pm2mp 23021*

Transformation of a polynomial matrix (over a ring) into a polynomial over matrices (over the same ring). (Contributed by AV, 5-Dec-2019.)

⊢ pMatToMatPoly = (𝑛 ∈ Fin, 𝑟 ∈ V ↦ (𝑚 ∈ (Base‘(𝑛 Mat (Poly₁‘𝑟))) ↦ ⦋(𝑛 Mat 𝑟) / 𝑎⦌⦋(Poly₁‘𝑎) / 𝑞⦌(𝑞 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑚 decompPMat 𝑘)( ·_𝑠 ‘𝑞)(𝑘(._g‘(mulGrp‘𝑞))(var₁‘𝑎)))))))

Theorem

pm2mpf1lem 23022*

Lemma for pm2mpf1 23027. (Contributed by AV, 14-Oct-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝑈 ∈ 𝐵 ∧ 𝐾 ∈ ℕ₀)) → ((coe₁‘(𝑄 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑈 decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋)))))‘𝐾) = (𝑈 decompPMat 𝐾))

Theorem

pm2mpval 23023*

Value of the transformation of a polynomial matrix into a polynomial over matrices. (Contributed by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ 𝑉) → 𝑇 = (𝑚 ∈ 𝐵 ↦ (𝑄 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑚 decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋))))))

Theorem

pm2mpfval 23024*

A polynomial matrix transformed into a polynomial over matrices. (Contributed by AV, 4-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ 𝑉 ∧ 𝑀 ∈ 𝐵) → (𝑇‘𝑀) = (𝑄 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑀 decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋)))))

Theorem

pm2mpcl 23025

The transformation of polynomial matrices into polynomials over matrices maps polynomial matrices to polynomials over matrices. (Contributed by AV, 5-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐿 = (Base‘𝑄)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → (𝑇‘𝑀) ∈ 𝐿)

Theorem

pm2mpf 23026

The transformation of polynomial matrices into polynomials over matrices is a function mapping polynomial matrices to polynomials over matrices. (Contributed by AV, 5-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐿 = (Base‘𝑄)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇:𝐵⟶𝐿)

Theorem

pm2mpf1 23027

The transformation of polynomial matrices into polynomials over matrices is a 1-1 function mapping polynomial matrices to polynomials over matrices. (Contributed by AV, 14-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐿 = (Base‘𝑄)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇:𝐵–1-1→𝐿)

Theorem

pm2mpcoe1 23028

A coefficient of the polynomial over matrices which is the result of the transformation of a polynomial matrix is the matrix consisting of the coefficients in the polynomial entries of the polynomial matrix. (Contributed by AV, 20-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝑀 ∈ 𝐵 ∧ 𝐾 ∈ ℕ₀)) → ((coe₁‘(𝑇‘𝑀))‘𝐾) = (𝑀 decompPMat 𝐾))

Theorem

idpm2idmp 23029

The transformation of the identity polynomial matrix into polynomials over matrices results in the identity of the polynomials over matrices. (Contributed by AV, 18-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → (𝑇‘(1_r‘𝐶)) = (1_r‘𝑄))

Theorem

mptcoe1matfsupp 23030*

The mapping extracting the entries of the coefficient matrices of a polynomial over matrices at a fixed position is finitely supported. (Contributed by AV, 6-Oct-2019.) (Proof shortened by AV, 23-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) ∧ 𝐼 ∈ 𝑁 ∧ 𝐽 ∈ 𝑁) → (𝑘 ∈ ℕ₀ ↦ (𝐼((coe₁‘𝑂)‘𝑘)𝐽)) finSupp (0_g‘𝑅))

Theorem

mply1topmatcllem 23031*

Lemma for mply1topmatcl 23033. (Contributed by AV, 6-Oct-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) ∧ 𝐼 ∈ 𝑁 ∧ 𝐽 ∈ 𝑁) → (𝑘 ∈ ℕ₀ ↦ ((𝐼((coe₁‘𝑂)‘𝑘)𝐽) · (𝑘𝐸𝑌))) finSupp (0_g‘𝑃))

Theorem

mply1topmatval 23032*

A polynomial over matrices transformed into a polynomial matrix. 𝐼 is the inverse function of the transformation 𝑇 of polynomial matrices into polynomials over matrices: (𝑇‘(𝐼‘𝑂)) = 𝑂) (see mp2pm2mp 23039). (Contributed by AV, 6-Oct-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    ⇒   ⊢ ((𝑁 ∈ 𝑉 ∧ 𝑂 ∈ 𝐿) → (𝐼‘𝑂) = (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑂)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))

Theorem

mply1topmatcl 23033*

A polynomial over matrices transformed into a polynomial matrix is a polynomial matrix. (Contributed by AV, 6-Oct-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) → (𝐼‘𝑂) ∈ 𝐵)

Theorem

mp2pm2mplem1 23034*

Lemma 1 for mp2pm2mp 23039. (Contributed by AV, 9-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) → (𝐼‘𝑂) = (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑂)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))

Theorem

mp2pm2mplem2 23035*

Lemma 2 for mp2pm2mp 23039. (Contributed by AV, 10-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) → (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑂)‘𝑘)𝑗) · (𝑘𝐸𝑌))))) ∈ 𝐵)

Theorem

mp2pm2mplem3 23036*

Lemma 3 for mp2pm2mp 23039. (Contributed by AV, 10-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝑃 = (Poly₁‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) ∧ 𝐾 ∈ ℕ₀) → ((𝐼‘𝑂) decompPMat 𝐾) = (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ ((coe₁‘(𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑂)‘𝑘)𝑗) · (𝑘𝐸𝑌)))))‘𝐾)))

Theorem

mp2pm2mplem4 23037*

Lemma 4 for mp2pm2mp 23039. (Contributed by AV, 12-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝑃 = (Poly₁‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) ∧ 𝐾 ∈ ℕ₀) → ((𝐼‘𝑂) decompPMat 𝐾) = ((coe₁‘𝑂)‘𝐾))

Theorem

mp2pm2mplem5 23038*

Lemma 5 for mp2pm2mp 23039. (Contributed by AV, 12-Oct-2019.) (Revised by AV, 5-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) → (𝑘 ∈ ℕ₀ ↦ (((𝐼‘𝑂) decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋))) finSupp (0_g‘𝑄))

Theorem

mp2pm2mp 23039*

A polynomial over matrices transformed into a polynomial matrix transformed back into the polynomial over matrices. (Contributed by AV, 12-Oct-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ 𝐼 = (𝑝 ∈ 𝐿 ↦ (𝑖 ∈ 𝑁, 𝑗 ∈ 𝑁 ↦ (𝑃 Σ_g (𝑘 ∈ ℕ₀ ↦ ((𝑖((coe₁‘𝑝)‘𝑘)𝑗) · (𝑘𝐸𝑌))))))    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑂 ∈ 𝐿) → (𝑇‘(𝐼‘𝑂)) = 𝑂)

Theorem

pm2mpghmlem2 23040*

Lemma 2 for pm2mpghm 23044. (Contributed by AV, 15-Oct-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → (𝑘 ∈ ℕ₀ ↦ ((𝑀 decompPMat 𝑘) ∗ (𝑘 ↑ 𝑋))) finSupp (0_g‘𝑄))

Theorem

pm2mpghmlem1 23041

Lemma 1 for pm2mpghm . (Contributed by AV, 15-Oct-2019.) (Revised by AV, 4-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ 𝐾 ∈ ℕ₀) → ((𝑀 decompPMat 𝐾) ∗ (𝐾 ↑ 𝑋)) ∈ 𝐿)

Theorem

pm2mpfo 23042

The transformation of polynomial matrices into polynomials over matrices is a function mapping polynomial matrices onto polynomials over matrices. (Contributed by AV, 12-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇:𝐵–onto→𝐿)

Theorem

pm2mpf1o 23043

The transformation of polynomial matrices into polynomials over matrices is a 1-1 function mapping polynomial matrices onto polynomials over matrices. (Contributed by AV, 14-Oct-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇:𝐵–1-1-onto→𝐿)

Theorem

pm2mpghm 23044

The transformation of polynomial matrices into polynomials over matrices is an additive group homomorphism. (Contributed by AV, 16-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇 ∈ (𝐶 GrpHom 𝑄))

Theorem

pm2mpgrpiso 23045

The transformation of polynomial matrices into polynomials over matrices is an additive group isomorphism. (Contributed by AV, 17-Oct-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇 ∈ (𝐶 GrpIso 𝑄))

Theorem

pm2mpmhmlem1 23046*

Lemma 1 for pm2mpmhm 23048. (Contributed by AV, 21-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐿 = (Base‘𝑄)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑙 ∈ ℕ₀ ↦ ((𝐴 Σ_g (𝑘 ∈ (0...𝑙) ↦ ((𝑥 decompPMat 𝑘)(._r‘𝐴)(𝑦 decompPMat (𝑙 − 𝑘))))) ∗ (𝑙 ↑ 𝑋))) finSupp (0_g‘𝑄))

Theorem

pm2mpmhmlem2 23047*

Lemma 2 for pm2mpmhm 23048. (Contributed by AV, 22-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐵 = (Base‘𝐶)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 (𝑇‘(𝑥(._r‘𝐶)𝑦)) = ((𝑇‘𝑥)(._r‘𝑄)(𝑇‘𝑦)))

Theorem

pm2mpmhm 23048

The transformation of polynomial matrices into polynomials over matrices is a homomorphism of multiplicative monoids. (Contributed by AV, 22-Oct-2019.) (Revised by AV, 6-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇 ∈ ((mulGrp‘𝐶) MndHom (mulGrp‘𝑄)))

Theorem

pm2mprhm 23049

The transformation of polynomial matrices into polynomials over matrices is a ring homomorphism. (Contributed by AV, 22-Oct-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇 ∈ (𝐶 RingHom 𝑄))

Theorem

pm2mprngiso 23050

The transformation of polynomial matrices into polynomials over matrices is a ring isomorphism. (Contributed by AV, 22-Oct-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝑇 = (𝑁 pMatToMatPoly 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝑇 ∈ (𝐶 RingIso 𝑄))

Theorem

pmmpric 23051

The ring of polynomial matrices over a ring is isomorphic to the ring of polynomials over matrices of the same dimension over the same ring. (Contributed by AV, 30-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → 𝐶 ≃_𝑟 𝑄)

Theorem

monmat2matmon 23052

The transformation of a polynomial matrix having scaled monomials with the same power as entries into a scaled monomial as a polynomial over matrices. (Contributed by AV, 11-Nov-2019.) (Revised by AV, 7-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐾 = (Base‘𝐴)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐼 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝐶)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐾 ∧ 𝐿 ∈ ℕ₀)) → (𝐼‘((𝐿𝐸𝑌) · (𝑇‘𝑀))) = (𝑀 ∗ (𝐿 ↑ 𝑋)))

Theorem

pm2mp 23053*

The transformation of a sum of matrices having scaled monomials with the same power as entries into a sum of scaled monomials as a polynomial over matrices. (Contributed by AV, 12-Nov-2019.) (Revised by AV, 7-Dec-2019.)

⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐶 = (𝑁 Mat 𝑃)    &   ⊢ 𝐵 = (Base‘𝐶)    &   ⊢ ∗ = ( ·_𝑠 ‘𝑄)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑄))    &   ⊢ 𝑋 = (var₁‘𝐴)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐾 = (Base‘𝐴)    &   ⊢ 𝑄 = (Poly₁‘𝐴)    &   ⊢ 𝐼 = (𝑁 pMatToMatPoly 𝑅)    &   ⊢ 𝐸 = (._g‘(mulGrp‘𝑃))    &   ⊢ 𝑌 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝐶)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ (𝐾 ↑_m ℕ₀) ∧ 𝑀 finSupp (0_g‘𝐴))) → (𝐼‘(𝐶 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛𝐸𝑌) · (𝑇‘(𝑀‘𝑛)))))) = (𝑄 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑀‘𝑛) ∗ (𝑛 ↑ 𝑋)))))

11.7  The characteristic polynomial

According to Wikipedia ("Characteristic polynomial", 31-Jul-2019, https://en.wikipedia.org/wiki/Characteristic_polynomial): "In linear algebra, the characteristic polynomial of a square matrix is a polynomial which is invariant under matrix similarity and has the eigenvalues as roots. It has the determinant and the trace of the matrix as coefficients.". Based on the definition of the characteristic polynomial of a square matrix (df-chpmat 23055) the eigenvalues and corresponding eigenvectors can be defined.

11.7.1  Definition and basic properties

The characteristic polynomial of a matrix 𝐴 is the determinant of the characteristic matrix of 𝐴: (𝑡𝐼 − 𝐴).

Syntax

cchpmat 23054

Extend class notation with the characteristic polynomial.

class CharPlyMat

Definition

df-chpmat 23055*

Define the characteristic polynomial of a square matrix. According to Wikipedia ("Characteristic polynomial", 31-Jul-2019, https://en.wikipedia.org/wiki/Characteristic_polynomial): "The characteristic polynomial of [an n x n matrix] A, denoted by p_A(t), is the polynomial defined by p_A ( t ) = det ( t I - A ) where I denotes the n-by-n identity matrix.". In addition, however, the underlying ring must be commutative, see definition in [Lang], p. 561: " Let k be a commutative ring ... Let M be any n x n matrix in k ... We define the characteristic polynomial P_M(t) to be the determinant det ( t I_n - M ) where I_n is the unit n x n matrix." To be more precise, the matrices A and I on the right hand side are matrices with coefficients of a polynomial ring. Therefore, the original matrix A over a given commutative ring must be transformed into corresponding matrices over the polynomial ring over the given ring. (Contributed by AV, 2-Aug-2019.)

⊢ CharPlyMat = (𝑛 ∈ Fin, 𝑟 ∈ V ↦ (𝑚 ∈ (Base‘(𝑛 Mat 𝑟)) ↦ ((𝑛 maDet (Poly₁‘𝑟))‘(((var₁‘𝑟)( ·_𝑠 ‘(𝑛 Mat (Poly₁‘𝑟)))(1_r‘(𝑛 Mat (Poly₁‘𝑟))))(-_g‘(𝑛 Mat (Poly₁‘𝑟)))((𝑛 matToPolyMat 𝑟)‘𝑚)))))

Theorem

chmatcl 23056

Closure of the characteristic matrix of a matrix. (Contributed by AV, 25-Oct-2019.) (Proof shortened by AV, 29-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝐻 = ((𝑋 · 1 ) − (𝑇‘𝑀))    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → 𝐻 ∈ (Base‘𝑌))

Theorem

chmatval 23057

The entries of the characteristic matrix of a matrix. (Contributed by AV, 2-Aug-2019.) (Proof shortened by AV, 10-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝐻 = ((𝑋 · 1 ) − (𝑇‘𝑀))    &   ⊢ ∼ = (-_g‘𝑃)    &   ⊢ 0 = (0_g‘𝑃)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ (𝐼 ∈ 𝑁 ∧ 𝐽 ∈ 𝑁)) → (𝐼𝐻𝐽) = if(𝐼 = 𝐽, (𝑋 ∼ (𝐼(𝑇‘𝑀)𝐽)), ( 0 ∼ (𝐼(𝑇‘𝑀)𝐽))))

Theorem

chpmatfval 23058*

Value of the characteristic polynomial function. (Contributed by AV, 2-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝐷 = (𝑁 maDet 𝑃)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 1 = (1_r‘𝑌)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ 𝑉) → 𝐶 = (𝑚 ∈ 𝐵 ↦ (𝐷‘((𝑋 · 1 ) − (𝑇‘𝑚)))))

Theorem

chpmatval 23059

The characteristic polynomial of a (square) matrix (expressed with a determinant). (Contributed by AV, 2-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝐷 = (𝑁 maDet 𝑃)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 1 = (1_r‘𝑌)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ 𝑉 ∧ 𝑀 ∈ 𝐵) → (𝐶‘𝑀) = (𝐷‘((𝑋 · 1 ) − (𝑇‘𝑀))))

Theorem

chpmatply1 23060

The characteristic polynomial of a (square) matrix over a commutative ring is a polynomial, see also the following remark in [Lang], p. 561: "[the characteristic polynomial] is an element of k[t]". (Contributed by AV, 2-Aug-2019.) (Proof shortened by AV, 29-Nov-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐸 = (Base‘𝑃)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → (𝐶‘𝑀) ∈ 𝐸)

Theorem

chpmatval2 23061*

The characteristic polynomial of a (square) matrix (expressed with the Leibnitz formula for the determinant). (Contributed by AV, 2-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝐺 = (SymGrp‘𝑁)    &   ⊢ 𝐻 = (Base‘𝐺)    &   ⊢ 𝑍 = (ℤRHom‘𝑃)    &   ⊢ 𝑆 = (pmSgn‘𝑁)    &   ⊢ 𝑈 = (mulGrp‘𝑃)    &   ⊢ × = (._r‘𝑃)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → (𝐶‘𝑀) = (𝑃 Σ_g (𝑝 ∈ 𝐻 ↦ (((𝑍 ∘ 𝑆)‘𝑝) × (𝑈 Σ_g (𝑥 ∈ 𝑁 ↦ ((𝑝‘𝑥)((𝑋 · 1 ) − (𝑇‘𝑀))𝑥)))))))

Theorem

chpmat0d 23062

The characteristic polynomial of the empty matrix. (Contributed by AV, 6-Aug-2019.)

⊢ 𝐶 = (∅ CharPlyMat 𝑅)    ⇒   ⊢ (𝑅 ∈ Ring → (𝐶‘∅) = (1_r‘(Poly₁‘𝑅)))

Theorem

chpmat1dlem 23063

Lemma for chpmat1d 23064. (Contributed by AV, 7-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐺 = (𝑁 Mat 𝑃)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((𝑅 ∈ Ring ∧ (𝑁 = {𝐼} ∧ 𝐼 ∈ 𝑉) ∧ 𝑀 ∈ 𝐵) → (𝐼((𝑋( ·_𝑠 ‘𝐺)(1_r‘𝐺))(-_g‘𝐺)(𝑇‘𝑀))𝐼) = (𝑋 − (𝑆‘(𝐼𝑀𝐼))))

Theorem

chpmat1d 23064

The characteristic polynomial of a matrix with dimension 1. (Contributed by AV, 7-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑆 = (algSc‘𝑃)    ⇒   ⊢ ((𝑅 ∈ CRing ∧ (𝑁 = {𝐼} ∧ 𝐼 ∈ 𝑉) ∧ 𝑀 ∈ 𝐵) → (𝐶‘𝑀) = (𝑋 − (𝑆‘(𝐼𝑀𝐼))))

Theorem

chpdmatlem0 23065

Lemma 0 for chpdmat 23069. (Contributed by AV, 18-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 0 = (0_g‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑄 = (𝑁 Mat 𝑃)    &   ⊢ 1 = (1_r‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑄)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring) → (𝑋 · 1 ) ∈ (Base‘𝑄))

Theorem

chpdmatlem1 23066

Lemma 1 for chpdmat 23069. (Contributed by AV, 18-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 0 = (0_g‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑄 = (𝑁 Mat 𝑃)    &   ⊢ 1 = (1_r‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑄)    &   ⊢ 𝑍 = (-_g‘𝑄)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) → ((𝑋 · 1 )𝑍(𝑇‘𝑀)) ∈ (Base‘𝑄))

Theorem

chpdmatlem2 23067

Lemma 2 for chpdmat 23069. (Contributed by AV, 18-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 0 = (0_g‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑄 = (𝑁 Mat 𝑃)    &   ⊢ 1 = (1_r‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑄)    &   ⊢ 𝑍 = (-_g‘𝑄)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((((((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ 𝑖 ∈ 𝑁) ∧ 𝑗 ∈ 𝑁) ∧ 𝑖 ≠ 𝑗) ∧ (𝑖𝑀𝑗) = 0 ) → (𝑖((𝑋 · 1 )𝑍(𝑇‘𝑀))𝑗) = (0_g‘𝑃))

Theorem

chpdmatlem3 23068

Lemma 3 for chpdmat 23069. (Contributed by AV, 18-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 0 = (0_g‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝑄 = (𝑁 Mat 𝑃)    &   ⊢ 1 = (1_r‘𝑄)    &   ⊢ · = ( ·_𝑠 ‘𝑄)    &   ⊢ 𝑍 = (-_g‘𝑄)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ 𝐾 ∈ 𝑁) → (𝐾((𝑋 · 1 )𝑍(𝑇‘𝑀))𝐾) = (𝑋 − (𝑆‘(𝐾𝑀𝐾))))

Theorem

chpdmat 23069*

The characteristic polynomial of a diagonal matrix. (Contributed by AV, 18-Aug-2019.) (Proof shortened by AV, 21-Nov-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 0 = (0_g‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ − = (-_g‘𝑃)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ ∀𝑖 ∈ 𝑁 ∀𝑗 ∈ 𝑁 (𝑖 ≠ 𝑗 → (𝑖𝑀𝑗) = 0 )) → (𝐶‘𝑀) = (𝐺 Σ_g (𝑘 ∈ 𝑁 ↦ (𝑋 − (𝑆‘(𝑘𝑀𝑘))))))

Theorem

chpscmat 23070*

The characteristic polynomial of a (nonempty!) scalar matrix. (Contributed by AV, 21-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 𝐷 = {𝑚 ∈ (Base‘𝐴) ∣ ∃𝑐 ∈ (Base‘𝑅)∀𝑖 ∈ 𝑁 ∀𝑗 ∈ 𝑁 (𝑖𝑚𝑗) = if(𝑖 = 𝑗, 𝑐, (0_g‘𝑅))}    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ − = (-_g‘𝑃)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐷 ∧ 𝐼 ∈ 𝑁 ∧ ∀𝑛 ∈ 𝑁 (𝑛𝑀𝑛) = 𝐸)) → (𝐶‘𝑀) = ((♯‘𝑁) ↑ (𝑋 − (𝑆‘𝐸))))

Theorem

chpscmat0 23071*

The characteristic polynomial of a (nonempty!) scalar matrix, expressed with its diagonal element. (Contributed by AV, 21-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 𝐷 = {𝑚 ∈ (Base‘𝐴) ∣ ∃𝑐 ∈ (Base‘𝑅)∀𝑖 ∈ 𝑁 ∀𝑗 ∈ 𝑁 (𝑖𝑚𝑗) = if(𝑖 = 𝑗, 𝑐, (0_g‘𝑅))}    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ − = (-_g‘𝑃)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐷 ∧ 𝐼 ∈ 𝑁 ∧ ∀𝑛 ∈ 𝑁 (𝑛𝑀𝑛) = (𝐼𝑀𝐼))) → (𝐶‘𝑀) = ((♯‘𝑁) ↑ (𝑋 − (𝑆‘(𝐼𝑀𝐼)))))

Theorem

chpscmatgsumbin 23072*

The characteristic polynomial of a (nonempty!) scalar matrix, expressed as finite group sum of binomials. (Contributed by AV, 2-Sep-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 𝐷 = {𝑚 ∈ (Base‘𝐴) ∣ ∃𝑐 ∈ (Base‘𝑅)∀𝑖 ∈ 𝑁 ∀𝑗 ∈ 𝑁 (𝑖𝑚𝑗) = if(𝑖 = 𝑗, 𝑐, (0_g‘𝑅))}    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝐹 = (._g‘𝑃)    &   ⊢ 𝐻 = (mulGrp‘𝑅)    &   ⊢ 𝐸 = (._g‘𝐻)    &   ⊢ 𝐼 = (inv_g‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐷 ∧ 𝐽 ∈ 𝑁 ∧ ∀𝑛 ∈ 𝑁 (𝑛𝑀𝑛) = (𝐽𝑀𝐽))) → (𝐶‘𝑀) = (𝑃 Σ_g (𝑙 ∈ (0...(♯‘𝑁)) ↦ (((♯‘𝑁)C𝑙)𝐹((((♯‘𝑁) − 𝑙)𝐸(𝐼‘(𝐽𝑀𝐽))) · (𝑙 ↑ 𝑋))))))

Theorem

chpscmatgsummon 23073*

The characteristic polynomial of a (nonempty!) scalar matrix, expressed as finite group sum of scaled monomials. (Contributed by AV, 2-Sep-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 𝐷 = {𝑚 ∈ (Base‘𝐴) ∣ ∃𝑐 ∈ (Base‘𝑅)∀𝑖 ∈ 𝑁 ∀𝑗 ∈ 𝑁 (𝑖𝑚𝑗) = if(𝑖 = 𝑗, 𝑐, (0_g‘𝑅))}    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ − = (-_g‘𝑃)    &   ⊢ 𝐹 = (._g‘𝑃)    &   ⊢ 𝐻 = (mulGrp‘𝑅)    &   ⊢ 𝐸 = (._g‘𝐻)    &   ⊢ 𝐼 = (inv_g‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑃)    &   ⊢ 𝑍 = (._g‘𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) ∧ (𝑀 ∈ 𝐷 ∧ 𝐽 ∈ 𝑁 ∧ ∀𝑛 ∈ 𝑁 (𝑛𝑀𝑛) = (𝐽𝑀𝐽))) → (𝐶‘𝑀) = (𝑃 Σ_g (𝑙 ∈ (0...(♯‘𝑁)) ↦ ((((♯‘𝑁)C𝑙)𝑍(((♯‘𝑁) − 𝑙)𝐸(𝐼‘(𝐽𝑀𝐽)))) · (𝑙 ↑ 𝑋)))))

Theorem

chp0mat 23074

The characteristic polynomial of the zero matrix. (Contributed by AV, 18-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 0 = (0_g‘𝐴)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) → (𝐶‘ 0 ) = ((♯‘𝑁) ↑ 𝑋))

Theorem

chpidmat 23075

The characteristic polynomial of the identity matrix. (Contributed by AV, 19-Aug-2019.)

⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝐺 = (mulGrp‘𝑃)    &   ⊢ ↑ = (._g‘𝐺)    &   ⊢ 𝐼 = (1_r‘𝐴)    &   ⊢ 𝑆 = (algSc‘𝑃)    &   ⊢ 1 = (1_r‘𝑅)    &   ⊢ − = (-_g‘𝑃)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing) → (𝐶‘𝐼) = ((♯‘𝑁) ↑ (𝑋 − (𝑆‘ 1 ))))

Theorem

chmaidscmat 23076

The characteristic polynomial of a matrix multiplied with the identity matrix is a scalar matrix. (Contributed by AV, 30-Oct-2019.) (Revised by AV, 5-Jul-2022.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝐸 = (Base‘𝑃)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝐾 = (Base‘𝑌)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑆 = (𝑁 ScMat 𝑃)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → ((𝐶‘𝑀) · 1 ) ∈ 𝑆)

11.7.2  The characteristic factor function G

In this subsection the function 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛)))))))) is discussed. This function is involved in the representation of the product of the characteristic matrix of a given matrix and its adjunct as an infinite sum, see cpmadugsum 23106. Therefore, this function is called "characteristic factor function" (in short "chfacf") in the following. It plays an important role in the proof of the Cayley-Hamilton theorem, see cayhamlem1 23094, cayhamlem3 23115 and cayhamlem4 23116.

Theorem

fvmptnn04if 23077*

The function values of a mapping from the nonnegative integers with four distinct cases. (Contributed by AV, 10-Nov-2019.)

⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, 𝐴, if(𝑛 = 𝑆, 𝐶, if(𝑆 < 𝑛, 𝐷, 𝐵))))    &   ⊢ (𝜑 → 𝑆 ∈ ℕ)    &   ⊢ (𝜑 → 𝑁 ∈ ℕ₀)    &   ⊢ (𝜑 → 𝑌 ∈ 𝑉)    &   ⊢ ((𝜑 ∧ 𝑁 = 0) → 𝑌 = ⦋𝑁 / 𝑛⦌𝐴)    &   ⊢ ((𝜑 ∧ 0 < 𝑁 ∧ 𝑁 < 𝑆) → 𝑌 = ⦋𝑁 / 𝑛⦌𝐵)    &   ⊢ ((𝜑 ∧ 𝑁 = 𝑆) → 𝑌 = ⦋𝑁 / 𝑛⦌𝐶)    &   ⊢ ((𝜑 ∧ 𝑆 < 𝑁) → 𝑌 = ⦋𝑁 / 𝑛⦌𝐷)    ⇒   ⊢ (𝜑 → (𝐺‘𝑁) = 𝑌)

Theorem

fvmptnn04ifa 23078*

The function value of a mapping from the nonnegative integers with four distinct cases for the first case. (Contributed by AV, 10-Nov-2019.)

⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, 𝐴, if(𝑛 = 𝑆, 𝐶, if(𝑆 < 𝑛, 𝐷, 𝐵))))    &   ⊢ (𝜑 → 𝑆 ∈ ℕ)    &   ⊢ (𝜑 → 𝑁 ∈ ℕ₀)    ⇒   ⊢ ((𝜑 ∧ 𝑁 = 0 ∧ ⦋𝑁 / 𝑛⦌𝐴 ∈ 𝑉) → (𝐺‘𝑁) = ⦋𝑁 / 𝑛⦌𝐴)

Theorem

fvmptnn04ifb 23079*

The function value of a mapping from the nonnegative integers with four distinct cases for the second case. (Contributed by AV, 10-Nov-2019.)

⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, 𝐴, if(𝑛 = 𝑆, 𝐶, if(𝑆 < 𝑛, 𝐷, 𝐵))))    &   ⊢ (𝜑 → 𝑆 ∈ ℕ)    &   ⊢ (𝜑 → 𝑁 ∈ ℕ₀)    ⇒   ⊢ ((𝜑 ∧ (0 < 𝑁 ∧ 𝑁 < 𝑆) ∧ ⦋𝑁 / 𝑛⦌𝐵 ∈ 𝑉) → (𝐺‘𝑁) = ⦋𝑁 / 𝑛⦌𝐵)

Theorem

fvmptnn04ifc 23080*

The function value of a mapping from the nonnegative integers with four distinct cases for the third case. (Contributed by AV, 10-Nov-2019.)

⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, 𝐴, if(𝑛 = 𝑆, 𝐶, if(𝑆 < 𝑛, 𝐷, 𝐵))))    &   ⊢ (𝜑 → 𝑆 ∈ ℕ)    &   ⊢ (𝜑 → 𝑁 ∈ ℕ₀)    ⇒   ⊢ ((𝜑 ∧ 𝑁 = 𝑆 ∧ ⦋𝑁 / 𝑛⦌𝐶 ∈ 𝑉) → (𝐺‘𝑁) = ⦋𝑁 / 𝑛⦌𝐶)

Theorem

fvmptnn04ifd 23081*

The function value of a mapping from the nonnegative integers with four distinct cases for the forth case. (Contributed by AV, 10-Nov-2019.)

⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, 𝐴, if(𝑛 = 𝑆, 𝐶, if(𝑆 < 𝑛, 𝐷, 𝐵))))    &   ⊢ (𝜑 → 𝑆 ∈ ℕ)    &   ⊢ (𝜑 → 𝑁 ∈ ℕ₀)    ⇒   ⊢ ((𝜑 ∧ 𝑆 < 𝑁 ∧ ⦋𝑁 / 𝑛⦌𝐷 ∈ 𝑉) → (𝐺‘𝑁) = ⦋𝑁 / 𝑛⦌𝐷)

Theorem

chfacfisf 23082*

The "characteristic factor function" is a function from the nonnegative integers to polynomial matrices. (Contributed by AV, 8-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → 𝐺:ℕ₀⟶(Base‘𝑌))

Theorem

chfacfisfcpmat 23083*

The "characteristic factor function" is a function from the nonnegative integers to constant polynomial matrices. (Contributed by AV, 19-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ 𝑆 = (𝑁 ConstPolyMat 𝑅)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ Ring ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → 𝐺:ℕ₀⟶𝑆)

Theorem

chfacffsupp 23084*

The "characteristic factor function" is finitely supported. (Contributed by AV, 20-Nov-2019.) (Proof shortened by AV, 23-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → 𝐺 finSupp (0_g‘𝑌))

Theorem

chfacfscmulcl 23085*

Closure of a scaled value of the "characteristic factor function". (Contributed by AV, 9-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠))) ∧ 𝐾 ∈ ℕ₀) → ((𝐾 ↑ 𝑋) · (𝐺‘𝐾)) ∈ (Base‘𝑌))

Theorem

chfacfscmul0 23086*

A scaled value of the "characteristic factor function" is zero almost always. (Contributed by AV, 9-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠))) ∧ 𝐾 ∈ (ℤ_≥‘(𝑠 + 2))) → ((𝐾 ↑ 𝑋) · (𝐺‘𝐾)) = 0 )

Theorem

chfacfscmulfsupp 23087*

A mapping of scaled values of the "characteristic factor function" is finitely supported. (Contributed by AV, 8-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ 𝑋) · (𝐺‘𝑖))) finSupp 0 )

Theorem

chfacfscmulgsum 23088*

Breaking up a sum of values of the "characteristic factor function" scaled by a polynomial. (Contributed by AV, 9-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ + = (+_g‘𝑌)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑌 Σ_g (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ 𝑋) · (𝐺‘𝑖)))) = ((𝑌 Σ_g (𝑖 ∈ (1...𝑠) ↦ ((𝑖 ↑ 𝑋) · ((𝑇‘(𝑏‘(𝑖 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑖))))))) + ((((𝑠 + 1) ↑ 𝑋) · (𝑇‘(𝑏‘𝑠))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0))))))

Theorem

chfacfpmmulcl 23089*

Closure of the value of the "characteristic factor function" multiplied with a constant polynomial matrix. (Contributed by AV, 23-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠))) ∧ 𝐾 ∈ ℕ₀) → ((𝐾 ↑ (𝑇‘𝑀)) × (𝐺‘𝐾)) ∈ (Base‘𝑌))

Theorem

chfacfpmmul0 23090*

The value of the "characteristic factor function" multiplied with a constant polynomial matrix is zero almost always. (Contributed by AV, 23-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠))) ∧ 𝐾 ∈ (ℤ_≥‘(𝑠 + 2))) → ((𝐾 ↑ (𝑇‘𝑀)) × (𝐺‘𝐾)) = 0 )

Theorem

chfacfpmmulfsupp 23091*

A mapping of values of the "characteristic factor function" multiplied with a constant polynomial matrix is finitely supported. (Contributed by AV, 23-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ (𝑇‘𝑀)) × (𝐺‘𝑖))) finSupp 0 )

Theorem

chfacfpmmulgsum 23092*

Breaking up a sum of values of the "characteristic factor function" multiplied with a constant polynomial matrix. (Contributed by AV, 23-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    &   ⊢ + = (+_g‘𝑌)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑌 Σ_g (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ (𝑇‘𝑀)) × (𝐺‘𝑖)))) = ((𝑌 Σ_g (𝑖 ∈ (1...𝑠) ↦ ((𝑖 ↑ (𝑇‘𝑀)) × ((𝑇‘(𝑏‘(𝑖 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑖))))))) + ((((𝑠 + 1) ↑ (𝑇‘𝑀)) × (𝑇‘(𝑏‘𝑠))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0))))))

Theorem

chfacfpmmulgsum2 23093*

Breaking up a sum of values of the "characteristic factor function" multiplied with a constant polynomial matrix. (Contributed by AV, 23-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    &   ⊢ + = (+_g‘𝑌)    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑌 Σ_g (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ (𝑇‘𝑀)) × (𝐺‘𝑖)))) = ((𝑌 Σ_g (𝑖 ∈ (1...𝑠) ↦ (((𝑖 ↑ (𝑇‘𝑀)) × (𝑇‘(𝑏‘(𝑖 − 1)))) − (((𝑖 + 1) ↑ (𝑇‘𝑀)) × (𝑇‘(𝑏‘𝑖)))))) + ((((𝑠 + 1) ↑ (𝑇‘𝑀)) × (𝑇‘(𝑏‘𝑠))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0))))))

Theorem

cayhamlem1 23094*

Lemma 1 for cayleyhamilton 23118. (Contributed by AV, 11-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ × = (._r‘𝑌)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ 0 = (0_g‘𝑌)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑛 ∈ ℕ₀ ↦ if(𝑛 = 0, ( 0 − ((𝑇‘𝑀) × (𝑇‘(𝑏‘0)))), if(𝑛 = (𝑠 + 1), (𝑇‘(𝑏‘𝑠)), if((𝑠 + 1) < 𝑛, 0 , ((𝑇‘(𝑏‘(𝑛 − 1))) − ((𝑇‘𝑀) × (𝑇‘(𝑏‘𝑛))))))))    &   ⊢ ↑ = (._g‘(mulGrp‘𝑌))    ⇒   ⊢ (((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) ∧ (𝑠 ∈ ℕ ∧ 𝑏 ∈ (𝐵 ↑_m (0...𝑠)))) → (𝑌 Σ_g (𝑖 ∈ ℕ₀ ↦ ((𝑖 ↑ (𝑇‘𝑀)) × (𝐺‘𝑖)))) = 0 )

11.7.3  The Cayley-Hamilton theorem

In this section, a direct algebraic proof for the Cayley-Hamilton theorem is provided, according to Wikipedia ("Cayley-Hamilton theorem", 09-Nov-2019, https://en.wikipedia.org/wiki/Cayley%E2%80%93Hamilton_theorem, section "A direct algebraic proof" (this approach is also used for proving Lemma 1.9 in [Hefferon] p. 427):

"This proof uses just the kind of objects needed to formulate the Cayley-Hamilton theorem: matrices with polynomials as entries. The matrix (t * I_n - A) whose determinant is the characteristic polynomial of A is such a matrix, and since polynomials [over a commutative ring] form a commutative ring, it has an adjugate

(1) B = adj(t * I_n - A) .

Then, according to the right-hand fundamental relation of the adjugate, one has

(2) ( t * I_n - A ) x B = det(t * I_n - A) x I_n = p(t) * I_n .

Since B is also a matrix with polynomials in t as entries, one can, for each i, collect the coefficients of t^i in each entry to form a matrix B_i of numbers, such that one has

(3) B = sum_{i = 0 to (n-1)} t^i B_i .

(The way the entries of B are defined makes clear that no powers higher than t^(n-1) occur). While this looks like a polynomial with matrices as coefficients, we shall not consider such a notion; it is just a way to write a matrix with polynomial entries as a linear combination of n constant matrices, and the coefficient t^i has been written to the left of the matrix to stress this point of view.

Now, one can expand the matrix product in our equation by bilinearity

(4) p(t) * I_n = ( t * I_n - A ) x B
= ( t * I_n - A ) x sum_{i = 0 to (n-1)} t^i * B_i
= sum_{i = 0 to (n-1)} t * I_n x t^i B_i - sum_{i = 0 to (n-1)} A * t^i B_i
= sum_{i = 0 to (n-1)} t^(i+1) * B_i - sum_{i = 0 to (n-1)} t^i * A x B_i
= t^n B_n-1 + sum_{i = 1 to (n-1)} t^i * ( B_i-1 - A x B_i ) - A x B₀ .

Writing

(5) p(t) I_n = t^n * I_n + t^(n-1) * c_(n-1) x I_n + ... + t * c₁ I_n + c₀ I_n ,

one obtains an equality of two matrices with polynomial entries, written as linear combinations of constant matrices with powers of t as coefficients. Such an equality can hold only if in any matrix position the entry that is multiplied by a given power t^i is the same on both sides; it follows that the constant matrices with coefficient t^i in both expressions must be equal. Writing these equations then for i from n down to 0, one finds

(6) B_n-1 = I_n , B_i-1 - A x B_i = c_i * I_n for 1 <= i <= n-1 , - A x B₀ = c₀ * I_n .

Finally, multiply the equation of the coefficients of t^i from the left by A^i, and sum up:

(7) A^n B_n-1 + sum_{i = 1 to (n-1)} ( A^i x B_i-1 - A^(i+1) x B_i ) - A x B₀ = A^n + c_n-1 * A^(n-1) + ... + c₁ * A + c₀ * I_n .

The left-hand sides form a telescoping sum and cancel completely; the right-hand sides add up to p(A):

(8) 0 = p(A) .

This completes the proof."

To formalize this approach, the steps mentioned in Wikipedia must be elaborated in more detail.

The first step is to formalize the preliminaries and the objective of the theorem. In Wikipedia, the Cayley-Hamilton theorem is stated as follows: "... the Cayley-Hamilton theorem ... states that every square matrix over a commutative ring ... satisfies its own characteristic equation." Or in more detail: "If A is a given n x n matrix and I_n is the n x n identity matrix, then the characteristic polynomial of A is defined as p(t) = det(t * I_n - A), where det is the determinant operation and t is a variable for a scalar element of the base ring. Since the entries of the matrix (t * I_n - A) are (linear or constant) polynomials in t, the determinant is also an n-th order monic polynomial in t. The Cayley-Hamilton theorem states that if one defines an analogous matrix equation, p(A), consisting of the replacement of the scalar eigenvalues t with the matrix A, then this polynomial in the matrix A results in the zero matrix,

p(A) = 0.

The powers of A, obtained by substitution from powers of t, are defined by repeated matrix multiplication; the constant term of p(t) gives a multiple of the power A^0, which is defined as the identity matrix. The theorem allows A^n to be expressed as a linear combination of the lower matrix powers of A. When the ring is a field, the Cayley-Hamilton theorem is equivalent to the statement that the minimal polynomial of a square matrix divides its characteristic polynomial."

Actually, the definition of the characteristic polynomial of a square matrix requires some attention. According to df-chpmat 23055, the characteristic polynomial of an 𝑁 x 𝑁 matrix 𝑀 over a ring 𝑅 is defined as

((𝑁 CharPlyMat 𝑅)‘𝑀) = (𝐷‘((𝑋 · 1 ) − (𝑇‘𝑀))))

where 𝐷 = (𝑁 maDet 𝑃) is the function mapping an 𝑁 x 𝑁 matrix over the polynomial ring over the ring 𝑅 to its determinant, 𝑋 = (var₁‘𝑅) is the variable of the polynomials over 𝑅, 1 is the 𝑁 x 𝑁 identity matrix as matrix over the polynomial ring over the ring 𝑅 (not the 𝑁 x 𝑁 identity matrix of the matrices over the ring 𝑅!) and (𝑇‘𝑀) = ((𝑁 matToPolyMat 𝑅)‘𝑀) is the matrix 𝑀 over a ring 𝑅 transformed into a constant matrix over the polynomial ring over the ring 𝑅. Thus · is the multiplication of a polynomial matrix with a "scalar", i.e. a polynomial (see chpmatval 23059).

By this definition, it is ensured that ((𝑋 · 1 ) − (𝑇‘𝑀)), the matrix whose determinant is the characteristic polynomial of the matrix 𝑀, is actually a matrix over the polynomial ring over the ring 𝑅, as stated in Wikipedia ("matrix with polynomials as entries"). This matrix is called the characteristic matrix of matrix 𝑀 (see Wikipedia "Polynomial matrix", 16-Nov-2019, https://en.wikipedia.org/wiki/Polynomial_matrix 23059). Following the notation in Wikipedia, we denote the characteristic polynomial of the matrix 𝑀, formally defined by ((𝑁 CharPlyMat 𝑅)‘𝑀) as "p(M)" in the comments. The characteristic matrix ((𝑋 · 1 ) − (𝑇‘𝑀)) will be denoted by "c(M)", so that "p(M) = det( c(M) )".

After the preliminaries are clarified, the objective of the Cayley-Hamilton theorem must be considered. As described in Wikipedia, the matrix 𝑀 must be "inserted" into its characteristic polynomial in an appropriate way. Since every polynomial can be represented as infinite, but finitely supported sum of monomials scaled by the corresponding coefficients (see ply1coe 22526), also the characteristic polynomial can be written in this way:

p(M) = sum_i ( p_i * M^i )

Here, * is the scalar multiplication in the algebra of the polynomials over the ring 𝑅, and the coefficients are elements of the ring 𝑅.

By this, we can "define" the insertion of the matrix M into its characteristic polynomial by "p(M) = sum( p_i * M^i)", see also cayleyhamilton1 23120. Here, * is the scalar multiplication in the algebra of the matrices over the ring 𝑅.

To prove the Cayley-Hamilton theorem, we have to show that "p(M) = 0", where 0 is the zero matrix.

In this section, the following class variables and informal identifiers (acronyms in the form "A(B)" or "A_B") are used:

class variable/ informal identifier	definiens	explanation
𝑁		An arbitrary finite set, used as dimension for matrices
𝑅		An arbitrary (commutative) ring: 𝑅 ∈ CRing
B(R)	(Base‘𝑅)	Base set of (the ring) 𝑅
𝐴	(𝑁 Mat 𝑅)	Algebra of 𝑁 x 𝑁 matrices over (the ring) 𝑅
𝐵	(Base‘𝐴)	Base set of the algebra of 𝑁 x 𝑁 matrices, i .e. the set of all 𝑁 x 𝑁 matrices
𝑀		An arbitrary 𝑁 x 𝑁 matrix
𝑃	(Poly1‘𝑅)	The algebra of polynomials over (the ring) 𝑅
B(P)	(Base‘𝑃)	Base set of the algebra of polynomials, i .e. the set of all polynomials
𝑋, XR	(var1‘𝑅)	The variable of polynomials over (the ring) 𝑅
𝑌, XA	(var1‘𝐴)	The variable of polynomials over matrices of the algebra 𝐴
↑	(.g‘(mulGrp‘𝑃))	The group exponentiation for polynomials over (the ring) 𝑅
^		Arbitrary group exponentiation
𝑈	(algSc‘𝑃)	The injection of scalars, i.e. elements of (the ring) 𝑅 into the base set of the algebra of polynomials over 𝑅
(𝑈‘𝑝), S(p)	((algSc‘𝑃)‘𝑝)	The element 𝑝 of (the ring) 𝑅 represented as polynomial over 𝑅
𝑌	(𝑁 Mat 𝑃)	Algebra of 𝑁 x 𝑁 matrices over (the polynomial ring) 𝑃 over the ring 𝑅
B(Y)	(Base‘𝑌)	Base set of the algebra of polynomial 𝑁 x 𝑁 matrices, i .e. the set of all polynomial 𝑁 x 𝑁 matrices
𝑄	(Poly1‘𝐴)	Algebra of polynomials over the ring of 𝑁 x 𝑁 matrices over the ring 𝑅
B(Q)	(Base‘𝑄)	Base set of the algebra of polynomials over the ring of 𝑁 x 𝑁 matrices over the ring 𝑅, i .e. the set of all polynomials having 𝑁 x 𝑁 matrices as coefficients
+, +	(+g‘𝑌)	The addition of polynomial matrices
−, -	(-g‘𝑌)	The subtraction of polynomial matrices
·, *Y	( ·𝑠 ‘𝑌)	The multiplication of a polynomial matrix with a scalar ( i. e. a polynomial)
*A	( ·𝑠 ‘𝐴)	The multiplication of a matrix with a scalar ( i. e. an element of the underlying ring)
*Q	( ·𝑠 ‘𝑄)	The multiplication of a polynomial over matrices with a scalar ( i. e. a matrix)
×, xY	(.r‘𝑌)	The multiplication of polynomial matrices
xA	(.r‘𝐴)	The multiplication of matrices
xQ	(.r‘𝑄)	The multiplication of polynomials over matrices
1, 1Y	(1r‘𝑌)	The identity matrix in the algebra of polynomial matrices over 𝑅
1A	(1r‘𝐴)	The identity matrix in the algebra of matrices over 𝑅
0, 0Y	(0g‘𝑌)	The zero matrix in the algebra of matrices consisting of polynomials
𝑇	(𝑁 matToPolyMat 𝑅)	The transformation of an 𝑁 x 𝑁 matrix over 𝑅 into a polynomial 𝑁 x 𝑁 matrix over 𝑅
T1(M)	(𝑇‘𝑀)	The matrix M transformed into a polynomial 𝑁 x 𝑁 matrix over 𝑅
U(M)	(𝑈‘𝑀)	The (constant) polynomial 𝑁 x 𝑁 matrix M transformed into a matrix over the ring 𝑅. Inverse function of 𝑇: (𝑇‘(𝑈‘𝑀)) = 𝑀 (see m2cpminvid2 22983 )
T2(M)	((𝑁 pMatToMatPoly 𝑅)‘𝑀)	The polynomial 𝑁 x 𝑁 matrix M transformed into a polynomial over the 𝑁 x 𝑁 matrices over 𝑅
𝐼, c(M)	((𝑋 · 1 ) − (𝑇‘𝑀))	The characteristic matrix of a matrix 𝑀, i.e. the matrix whose determinant is the characteristic polynomial of the matrix 𝑀
𝐶	(𝑁 CharPlyMat 𝑅)	The function mapping a matrix over (a ring) 𝑅 to its characteristic polynomial
𝐾, p(M)	(𝐶‘𝑀)	The characteristic polynomial of a matrix over (a ring) 𝑅
𝐻	(𝐾 · 1 )	The scalar matrix (diagonal matrix) with the characteristic polynomial of a matrix as diagonal elements
𝐽	(𝑁 maAdju 𝑃)	The function mapping a matrix consisting of polynomials to its adjugate ("matrix of cofactors")
𝑊, adj(cm(M))	(𝐽‘𝐼)	The adjugate of the characteristic matrix of the matrix 𝑀

Using this notation, we have:

1. "c(M) e. B(Y)", or 𝐼 ∈ (Base‘𝑌), see chmatcl 23056
2. "p(M) e. B(P)", or 𝐾 ∈ (Base‘𝑃), see chpmatply1 23060
3. "T(M) e. B(Y)", or (𝑇‘𝑀) ∈ (Base‘𝑌), see mat2pmatbas 22954
4. 𝐽:(Base‘𝑌)⟶(Base‘𝑌), see maduf 22866
5. "adj(cm(M)) e. B(Y)", or 𝑊 ∈ (Base‘𝑌)

Following the proof shown in Wikipedia, the following steps are performed:

1. Write 𝑊, the adjugate of the characteristic matrix, as a finite sum of scaled monomials, see pmatcollpw3fi1 23016:
   adj(cm(M)) = sum_{i=0 to s} ( X_R ^i *_Y T₁(b(i)) )
   where b(i) are matrices over the ring 𝑅, so T₁(b(i)) are constant polynomial matrices.
   This step corresponds to (3) in Wikipedia. In contrast to Wikipedia, we write 𝑊 as finite sum of not exactly determined number of summands, which may be greater than needed (including summands of value 0). This will be sufficient to provide a representation of (𝐼 × 𝑊) as infinite, but finitely supported sum, see step 3.
2. Write (𝐼 × 𝑊), the product of the characteristic matrix and its adjugate as finite sum of scaled monomials, see cpmadugsumfi 23105. This representation is obtained by replacing 𝑊 by the representation resulting from step 1. and performing calculation rules available for the associative algebra of matrices over polynomials over a commutative ring:
   cm(M) *_Y adj(cm(M)) = sum_{i=0 to s} ( X_R ^i *_Y ( T₁(b(i-1)) - T₁(M) x_Y T₁(b(i)) ) ) + X_R ^(s+1) *_Y ( T₁(b(s)) - T₁(M) x_Y T₁(b(0))
   where b(i) are matrices over 𝑅, so T₁(b(i)) are constant polynomial matrices:
   cm(M) *_Y adj(cm(M))
   = cm(M) *_Y sum_{i=0 to s} ( X_R ^i *_Y T₁(b(i)) ) [see pmatcollpw3fi1 23016 (step 1.)]
   = ( ( X_A *_Y 1_Y ) - T₁(M) ) *_Y sum_{i=0 to s} ( X_R ^i *_Y T₁(b(i)) ) [def. of cm(M)]
   = ( X_A *_Y 1_Y ) *_Y sum_{i=0 to s} ( X_R ^i *_Y T₁(b(i)) ) - T₁(M) *_Y sum_{i=0 to s} ( X_R ^i *_Y T₁(b(i)) ) [see ringsubdir 20453]
   = sum_{i=0 to s} ( X_R ^i *_Y ( T₁(b(i-1)) - T₁(M) x_Y T₁(b(i)) ) ) + X_R ^(s+1) *_Y ( T₁(b(s)) - T₁(M) x_Y T₁(b(0)) [see cpmadugsumlemF 23104]
   This step corresponds partially to (4) in Wikipedia.
3. Write (𝐼 × 𝑊) as infinite, but finitely supported sum of scaled monomials, see cpmadugsum 23106:
   cm(M) * adj(cm(M)) = sum_i ( X_R ^i *_Y G(i) )
   This representation is obtained by defining a function G for the coefficients, which we call "characteristic factor function", see chfacfisf 23082, which covers the special terms and the padding with 0. G(i) is a constant polynomial matrix (see chfacfisfcpmat 23083). This step corresponds partially to (4) in Wikipedia, with summands of value 0 added.
4. Write 𝐻 = (𝐾 · 1 ), the scalar matrix (diagonal matrix) with the characteristic polynomial of a matrix as diagonal elements, as infinite, but finitely supported sum of scaled monomials. See cpmidgsum 23096:
   p(m) *_Y I_Y = sum_i ( X_R ^i *_Y ( S(p_i) *_Y I_Y ) )
   The proof of cpmidgsum 23096 is making use of pmatcollpwscmat 23019, because 𝐻 = (𝐾 · 1 ) is a scalar/diagonal polynomial matrix with the characteristic polynomial "p(M)" as diagonal entries (since p_i is an element of the ring 𝑅, S(p_i) is a (constant) polynomial). This corresponds to (5) in Wikipedia, with summands of value 0 added.
5. Transform the sum representation of (𝐼 × 𝑊) from step 3. into polynomials over matrices:
   T₂(cm(M) * adj(cm(M))) = sum_i ( U(G(i)) *_Q X_A ^i ) [see cpmadumatpoly 23111]
   where U(G(i)) is a matrix over the ring 𝑅.
6. Transform the sum representation of 𝐻 from step 4. into polynomials over matrices:
   T₂(p(m) *_Y I_Y) = sum_i ( p_i *_A I_A ) *_Q X_A ^i ) [see cpmidpmat 23101]
7. Equate the sum representations resulting from steps 5. and 6. by using cpmadurid 23095 to obtain the equation
   sum_i ( U(G(i)) *_Q X_A ^i ) = sum_i ( p_i *_A I_A ) *_Q X_A ^i ):
   sum_i ( U(G(i)) *_Q X_A ^i )
   = T₂(cm(M) * adj(cm(M))) [see step 5.]
   = T₂(p(m) *_Y I_Y) [see cpmadurid 23095]
   = sum_i ( p_i *_A I_A ) *_Q X_A ^i ) [see step 6.]
   Note that this step is contained in the proof of chcoeffeq 23114, see step 9. This step corresponds to the conclusion from (4) and (5) in Wikipedia, with summands of value 0 added.
8. Compare the sum representations of step 7. to obtain the equations U(G(i)) = p_i *_A I_A , see chcoeffeqlem 23113. This corresponds to (6) in Wikipedia. Since the coefficients of the transformed representations and the original representations are identical, the equations of the coefficients are also valid for the original representations of steps 3. and 4.
9. Multiply the equations of the coefficients from step 8. from the left by M^i, and sum up, see chcoeffeq 23114:
   sum_i ( M^i x_A U(G(i)) ) = sum_i ( M^i x_A ( p_i *_A I_A) )
   This corresponds to (7) in Wikipedia.
10. Transform the right hand side of the equation in step 9. into an appropriate form, see cayhamlem3 23115:
    sum_i ( p_i *_A M^i )
    = sum_i ( M^i x_A ( p_i *_A I_A) ) [see cayhamlem2 23112]
    = sum_i ( M^i x_A U(G(i)) ) [see chcoeffeq 23114]
11. Apply the theorem for telescoping sums, see telgsumfz 20120, to the sum sum_i ( T₁(M)^i x_Y G(i) ), which results in an equation to 0:
    sum_i ( T₁(M)^i x_Y G(i) ) = 0_Y, see cayhamlem1 23094:
    sum_i ( T₁(M)^i x_Y G(i) )
    = sum_{i=1 to s} ( T₁(M)^i x_Y T₁(b(i-1)) - T₁(M)^(i+1) x_Y T₁(b(i)) )
    + ( T₁(M)^(s+1) x_Y T₁(b(s)) - T₁(M) x_Y T₁(b(0)) ) [see chfacfpmmulgsum2 23093]
    = ( T₁(M) x_Y T₁(b(0)) - T₁(M)^(s+1) x_Y T₁(b(s)) ) + ( T₁ M)^(s+1) x_Y T₁(b(s)) - T₁(M) x_Y T₁(b(0)) ) [see telgsumfz 20120]
    = 0_Y [see grpnpncan0 19162] This step corresponds partially to (8) in Wikipedia.
12. Since 𝑇 is a ring homomorphism (see mat2pmatrhm 22962), the left hand side of the equation in step 10. can be transformed into a representation appropriate to apply the result of step 11., see cayhamlem4 23116:
    sum_i ( p_i *_A M^i )
    = sum_i ( M^i x_A U(G(i)) ) [see cayhamlem3 23115 (step 10.)]
    = U(T₁(sum_i ( M^i x_A U(G(i)) ))) [see m2cpminvid 22981]
    = U(sum_i T₁( M^i x_A U(G(i)) )) [see gsummptmhm 20070]
    = U(sum_i ( T₁(M^i) x_Y T₁(U(G(i))) )) [see rhmmul 20634]
    = U(sum_i ( T₁(M)^i x_Y T₁(U(G(i))) )) [see mhmmulg 19241]
    = U(sum_i ( T₁(M)^i x_Y G(i) )) [see m2cpminvid2 22983 ]
    
13. Finally, combine the results of steps 11. and 12., and use the fact that 𝑇 (and therefore also its inverse 𝑈) is an injective ring homomorphism (see mat2pmatf1 22957 and mat2pmatrhm 22962) to transform the equality resulting from steps 11. and 12. into the desired equation sum_i ( p_i *_A M^i ) = 0_A , see cayleyhamilton 23118 resp. cayleyhamilton0 23117:
    sum_i ( p_i *_A M^i )
    = U(sum_i ( T₁(M)^i x_Y G(i) )) [see cayhamlem4 23116 (step 12.)]
    = U(0_Y ) [see cayhamlem1 23094 (step 11.)]
    = 0_A [see m2cpminv0 22989]

The transformations in steps 5., 6., 10., 12. and 13. are not mentioned in the proof provided in Wikipedia, since it makes no distinction between a matrix over a ring 𝑅 and its representation as matrix over the polynomial ring over the ring 𝑅 in general!

Theorem

cpmadurid 23095

The right-hand fundamental relation of the adjugate (see madurid 22869) applied to the characteristic matrix of a matrix. (Contributed by AV, 25-Oct-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ − = (-_g‘𝑌)    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝐼 = ((𝑋 · 1 ) − (𝑇‘𝑀))    &   ⊢ 𝐽 = (𝑁 maAdju 𝑃)    &   ⊢ × = (._r‘𝑌)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → (𝐼 × (𝐽‘𝐼)) = ((𝐶‘𝑀) · 1 ))

Theorem

cpmidgsum 23096*

Representation of the identity matrix multiplied with the characteristic polynomial of a matrix as group sum. (Contributed by AV, 7-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐾 = (𝐶‘𝑀)    &   ⊢ 𝐻 = (𝐾 · 1 )    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → 𝐻 = (𝑌 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛 ↑ 𝑋) · ((𝑈‘((coe₁‘𝐾)‘𝑛)) · 1 )))))

Theorem

cpmidgsumm2pm 23097*

Representation of the identity matrix multiplied with the characteristic polynomial of a matrix as group sum with a matrix to polynomial matrix transformation. (Contributed by AV, 13-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐾 = (𝐶‘𝑀)    &   ⊢ 𝐻 = (𝐾 · 1 )    &   ⊢ 𝑂 = (1_r‘𝐴)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐴)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → 𝐻 = (𝑌 Σ_g (𝑛 ∈ ℕ₀ ↦ ((𝑛 ↑ 𝑋) · (𝑇‘(((coe₁‘𝐾)‘𝑛) ∗ 𝑂))))))

Theorem

cpmidpmatlem1 23098*

Lemma 1 for cpmidpmat 23101. (Contributed by AV, 13-Nov-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐾 = (𝐶‘𝑀)    &   ⊢ 𝐻 = (𝐾 · 1 )    &   ⊢ 𝑂 = (1_r‘𝐴)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐴)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑘 ∈ ℕ₀ ↦ (((coe₁‘𝐾)‘𝑘) ∗ 𝑂))    ⇒   ⊢ (𝐿 ∈ ℕ₀ → (𝐺‘𝐿) = (((coe₁‘𝐾)‘𝐿) ∗ 𝑂))

Theorem

cpmidpmatlem2 23099*

Lemma 2 for cpmidpmat 23101. (Contributed by AV, 14-Nov-2019.) (Proof shortened by AV, 7-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐾 = (𝐶‘𝑀)    &   ⊢ 𝐻 = (𝐾 · 1 )    &   ⊢ 𝑂 = (1_r‘𝐴)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐴)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑘 ∈ ℕ₀ ↦ (((coe₁‘𝐾)‘𝑘) ∗ 𝑂))    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → 𝐺 ∈ (𝐵 ↑_m ℕ₀))

Theorem

cpmidpmatlem3 23100*

Lemma 3 for cpmidpmat 23101. (Contributed by AV, 14-Nov-2019.) (Proof shortened by AV, 7-Dec-2019.)

⊢ 𝐴 = (𝑁 Mat 𝑅)    &   ⊢ 𝐵 = (Base‘𝐴)    &   ⊢ 𝑃 = (Poly₁‘𝑅)    &   ⊢ 𝑌 = (𝑁 Mat 𝑃)    &   ⊢ 𝑋 = (var₁‘𝑅)    &   ⊢ ↑ = (._g‘(mulGrp‘𝑃))    &   ⊢ · = ( ·_𝑠 ‘𝑌)    &   ⊢ 1 = (1_r‘𝑌)    &   ⊢ 𝑈 = (algSc‘𝑃)    &   ⊢ 𝐶 = (𝑁 CharPlyMat 𝑅)    &   ⊢ 𝐾 = (𝐶‘𝑀)    &   ⊢ 𝐻 = (𝐾 · 1 )    &   ⊢ 𝑂 = (1_r‘𝐴)    &   ⊢ ∗ = ( ·_𝑠 ‘𝐴)    &   ⊢ 𝑇 = (𝑁 matToPolyMat 𝑅)    &   ⊢ 𝐺 = (𝑘 ∈ ℕ₀ ↦ (((coe₁‘𝐾)‘𝑘) ∗ 𝑂))    ⇒   ⊢ ((𝑁 ∈ Fin ∧ 𝑅 ∈ CRing ∧ 𝑀 ∈ 𝐵) → 𝐺 finSupp (0_g‘𝐴))