Theorem: FirstOrder.Language.DirectLimit.exists_quotient_mk'_sigma_mk'_eq
File: Mathlib/ModelTheory/DirectLimit.lean

Proof steps:
state_before: L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
⊢ ∃ i y, x = fun a => ⟦Structure.Sigma.mk f i (y a)⟧
state_after: case intro
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
⊢ ∃ i y, x = fun a => ⟦Structure.Sigma.mk f i (y a)⟧
tactic: obtain ⟨i, hi⟩ := Finite.bddAbove_range fun a => (x a).out.1
state_before: case intro
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
⊢ ∃ i y, x = fun a => ⟦Structure.Sigma.mk f i (y a)⟧
state_after: case intro
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
⊢ x = fun a => ⟦Structure.Sigma.mk f i (unify f (Quotient.out ∘ x) i hi a)⟧
tactic: refine ⟨i, unify f (Quotient.out ∘ x) i hi, ?_⟩
state_before: case intro
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
⊢ x = fun a => ⟦Structure.Sigma.mk f i (unify f (Quotient.out ∘ x) i hi a)⟧
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
⊢ x a = ⟦Structure.Sigma.mk f i (unify f (Quotient.out ∘ x) i hi a)⟧
tactic: ext a
state_before: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
⊢ x a = ⟦Structure.Sigma.mk f i (unify f (Quotient.out ∘ x) i hi a)⟧
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f ((Quotient.out ∘ x) a).fst i ⋯) ((Quotient.out ∘ x) a).snd)
tactic: rw [Quotient.eq_mk_iff_out, unify]
state_before: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f ((Quotient.out ∘ x) a).fst i ⋯) ((Quotient.out ∘ x) a).snd)
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f ((Quotient.out ∘ x) a).fst i r) ((Quotient.out ∘ x) a).snd)
tactic: generalize_proofs r
state_before: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f ((Quotient.out ∘ x) a).fst i r) ((Quotient.out ∘ x) a).snd)
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)
tactic: change _ ≈ .mk f i (f (Quotient.out (x a)).fst i r (Quotient.out (x a)).snd)
state_before: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
this : (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)
tactic: have : (.mk f i (f (Quotient.out (x a)).fst i r (Quotient.out (x a)).snd) : Σˣ f).fst ≤ i :=
    le_rfl
state_before: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
this : (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst ≤ i
⊢ Quotient.out (x a) ≈ Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)
state_after: case intro.h
L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
this : (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst ≤ i
⊢ (f (Quotient.out (x a)).fst i ⋯) (Quotient.out (x a)).snd =
    (f (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst i this)
      (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).snd

L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
this : (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst ≤ i
⊢ (Quotient.out (x a)).fst ∈ range fun a => (Quotient.out (x a)).fst
tactic: rw [equiv_iff G f (i := i) (hi _) this]
state_before: L : Language
ι : Type v
inst✝⁵ : Preorder ι
G : ι → Type w
inst✝⁴ : (i : ι) → L.Structure (G i)
f : (i j : ι) → i ≤ j → G i ↪[L] G j
inst✝³ : IsDirected ι fun x x_1 => x ≤ x_1
inst✝² : DirectedSystem G fun i j h => ⇑(f i j h)
inst✝¹ : Nonempty ι
α : Type u_1
inst✝ : Finite α
x : α → DirectLimit G f
i : ι
hi : i ∈ upperBounds (range fun a => (Quotient.out (x a)).fst)
a : α
r : ((Quotient.out ∘ x) a).fst ≤ i
this : (Structure.Sigma.mk f i ((f (Quotient.out (x a)).fst i r) (Quotient.out (x a)).snd)).fst ≤ i
⊢ (Quotient.out (x a)).fst ∈ range fun a => (Quotient.out (x a)).fst
state_after: no goals
tactic: exact ⟨a, rfl⟩