Theorem: CliffordAlgebra.evenOdd_induction
File: Mathlib/LinearAlgebra/CliffordAlgebra/Grading.lean

Proof steps:
state_before: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ motive x hx
state_after: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (i : { n_1 // ↑n_1 = n }) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ ↑i), motive x ⋯
tactic: apply Submodule.iSup_induction' (C := motive) _ (range_ι_pow 0 (Submodule.zero_mem _)) add
state_before: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (i : { n_1 // ↑n_1 = n }) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ ↑i), motive x ⋯
state_after: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (val : ℕ) (property : ↑val = n) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ ↑⟨val, property⟩),
    motive x ⋯
tactic: refine Subtype.rec ?_
state_before: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (val : ℕ) (property : ↑val = n) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ ↑⟨val, property⟩),
    motive x ⋯
state_after: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (val : ℕ) (property : ∃ k, val = 2 * k + n.val) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ val),
    motive x ⋯
tactic: simp_rw [ZMod.natCast_eq_iff, add_comm n.val]
state_before: R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
⊢ ∀ (val : ℕ) (property : ∃ k, val = 2 * k + n.val) (x : CliffordAlgebra Q) (hx : x ∈ LinearMap.range (ι Q) ^ val),
    motive x ⋯
state_after: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
⊢ ∀ (hx : xv ∈ LinearMap.range (ι Q) ^ (2 * k + n.val)), motive xv ⋯
tactic: rintro n' ⟨k, rfl⟩ xv
state_before: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
⊢ ∀ (hx : xv ∈ LinearMap.range (ι Q) ^ (2 * k + n.val)), motive xv ⋯
state_after: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
⊢ ∀ (hx : xv ∈ (LinearMap.range (ι Q) ^ 2) ^ k * LinearMap.range (ι Q) ^ n.val), motive xv ⋯
tactic: simp_rw [pow_add, pow_mul]
state_before: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
⊢ ∀ (hx : xv ∈ (LinearMap.range (ι Q) ^ 2) ^ k * LinearMap.range (ι Q) ^ n.val), motive xv ⋯
state_after: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
hxv : xv ∈ (LinearMap.range (ι Q) ^ 2) ^ k * LinearMap.range (ι Q) ^ n.val
⊢ motive xv ⋯
tactic: intro hxv
state_before: case intro
R : Type u_1
M : Type u_2
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
Q : QuadraticForm R M
n : ZMod 2
motive : (x : CliffordAlgebra Q) → x ∈ evenOdd Q n → Prop
range_ι_pow : ∀ (v : CliffordAlgebra Q) (h : v ∈ LinearMap.range (ι Q) ^ n.val), motive v ⋯
add :
  ∀ (x y : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n) (hy : y ∈ evenOdd Q n),
    motive x hx → motive y hy → motive (x + y) ⋯
ι_mul_ι_mul :
  ∀ (m₁ m₂ : M) (x : CliffordAlgebra Q) (hx : x ∈ evenOdd Q n), motive x hx → motive ((ι Q) m₁ * (ι Q) m₂ * x) ⋯
x : CliffordAlgebra Q
hx : x ∈ evenOdd Q n
k : ℕ
xv : CliffordAlgebra Q
hxv : xv ∈ (LinearMap.range (ι Q) ^ 2) ^ k * LinearMap.range (ι Q) ^ n.val
⊢ motive xv ⋯
state_after: no goals
tactic: induction hxv using Submodule.mul_induction_on' with
  | mem_mul_mem a ha b hb =>
    induction ha using Submodule.pow_induction_on_left' with
    | algebraMap r =>
      simp_rw [← Algebra.smul_def]
      exact range_ι_pow _ (Submodule.smul_mem _ _ hb)
    | add x y n hx hy ihx ihy =>
      simp_rw [add_mul]
      apply add _ _ _ _ ihx ihy
    | mem_mul x hx n'' y hy ihy =>
      revert hx
      simp_rw [pow_two]
      intro hx2
      induction hx2 using Submodule.mul_induction_on' with
      | mem_mul_mem m hm n hn =>
        simp_rw [LinearMap.mem_range] at hm hn
        obtain ⟨m₁, rfl⟩ := hm; obtain ⟨m₂, rfl⟩ := hn
        simp_rw [mul_assoc _ y b]
        exact ι_mul_ι_mul _ _ _ _ ihy
      | add x hx y hy ihx ihy =>
        simp_rw [add_mul]
        apply add _ _ _ _ ihx ihy
  | add x y hx hy ihx ihy =>
    apply add _ _ _ _ ihx ihy