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Add lean source and binary files (part 84)
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import Mathlib
import OAI.LinearAlgebra.MatrixFields.Arithmetic.RecursiveBlockPrograms
namespace OAI
namespace MatrixAllFields
open scoped BigOperators Topology Polynomial
noncomputable section
open scoped BigOperators
namespace MatrixMultiplication.Arithmetic
section
namespace Program
variable {F Input : Type*}
def registerCost : {r : ℕ} → Program F Input r → Fin r → ℕ
| 0, .nil => Fin.elim0
| _ + 1, .step p g => Fin.cases g.cost p.registerCost
theorem sum_registerCost {r : ℕ} (p : Program F Input r) :
∑ i, p.registerCost i = p.cost := by
induction p with
| nil => simp [registerCost, cost]
| step p g ih => simp [registerCost, Fin.sum_univ_succ, ih, Nat.add_comm]
theorem eval_eq_constant_or_input_of_registerCost_eq_zero [Field F]
{r : ℕ} (p : Program F Input r) (i : Fin r) (hi : p.registerCost i = 0) :
(∃ z : F, ∀ inputs, p.eval inputs i = z) ∨
(∃ a : Input, ∀ inputs, p.eval inputs i = inputs a) := by
revert i
induction p with
| nil => intro i; exact Fin.elim0 i
| @step r p g ih =>
intro i hi
revert hi
refine Fin.cases ?_ (fun j => ?_) i
· intro hi
change g.cost = 0 at hi
cases g with
| constant z => exact Or.inl ⟨z, fun _ => rfl⟩
| input a => exact Or.inr ⟨a, fun _ => rfl⟩
| add a b => simp [Gate.cost] at hi
| sub a b => simp [Gate.cost] at hi
| mul a b => simp [Gate.cost] at hi
· intro hi
simpa only [eval_step_succ] using ih j hi
end Program
section ElementaryMatrices
variable {F : Type*} [Field F] {a b c : ℕ}
def elementaryLeft (i : Fin a) (j : Fin b) : Matrix (Fin a) (Fin b) F :=
fun x y => if x = i then if y = j then 1 else 0 else 0
def elementaryRight (j : Fin b) (k : Fin c) : Matrix (Fin b) (Fin c) F :=
fun y z => if z = k then if y = j then 1 else 0 else 0
theorem elementaryProduct (i x : Fin a) (j : Fin b) (k z : Fin c) :
(elementaryLeft (F := F) i j * elementaryRight (F := F) j k) x z =
if (x, z) = (i, k) then 1 else 0 := by
by_cases hi : x = i <;> by_cases hk : z = k <;>
simp [Matrix.mul_apply, elementaryLeft, elementaryRight, hi, hk]
end ElementaryMatrices
namespace MatrixAlgorithm
variable {F : Type*} [Field F] {a b c : ℕ}
theorem output_injective (P : MatrixAlgorithm F a b c) (hb : 1 ≤ b)
(hP : P.Correct) : Function.Injective (fun o : Fin a × Fin c => P.output o.1 o.2) := by
classical
intro x y hxy
change P.output x.1 x.2 = P.output y.1 y.2 at hxy
let j : Fin b := ⟨0, by omega⟩
let A := elementaryLeft (F := F) x.1 j
let B := elementaryRight (F := F) j x.2
have hx := congrFun (congrFun (hP A B) x.1) x.2
have hy := congrFun (congrFun (hP A B) y.1) y.2
have heq : (A * B) x.1 x.2 = (A * B) y.1 y.2 := by
rw [← hx, ← hy]
change P.program.eval (matrixInputs A B) (P.output x.1 x.2) =
P.program.eval (matrixInputs A B) (P.output y.1 y.2)
rw [hxy]
simp only [A, B, elementaryProduct, Prod.eta, ite_true] at heq
by_contra hne
have hyx : y ≠ x := Ne.symm hne
simp [hyx] at heq
theorem one_le_output_registerCost (P : MatrixAlgorithm F a b c) (hb : 1 ≤ b)
(hP : P.Correct) (i : Fin a) (k : Fin c) :
1 ≤ P.program.registerCost (P.output i k) := by
by_contra hn
have hzero : P.program.registerCost (P.output i k) = 0 := by omega
let j : Fin b := ⟨0, by omega⟩
have hentry (A : Matrix (Fin a) (Fin b) F) (B : Matrix (Fin b) (Fin c) F) :
P.program.eval (matrixInputs A B) (P.output i k) = (A * B) i k :=
congrFun (congrFun (hP A B) i) k
rcases P.program.eval_eq_constant_or_input_of_registerCost_eq_zero
(P.output i k) hzero with ⟨z, hz⟩ | ⟨u, hu⟩
· have hz0 : z = 0 := by
have h := hentry 0 0
rw [hz] at h
simpa using h
have hz1 : z = 1 := by
have h := hentry (elementaryLeft i j) (elementaryRight j k)
rw [hz] at h
simpa only [elementaryProduct, ite_true] using h
exact (zero_ne_one : (0 : F) ≠ 1) (hz0.symm.trans hz1)
· rcases u with ⟨x, y⟩ | ⟨y, z⟩
· have h := hentry (fun _ _ => 1) 0
rw [hu] at h
change (1 : F) = ∑ _ : Fin b, (1 : F) * 0 at h
simp at h
· have h := hentry 0 (fun _ _ => 1)
rw [hu] at h
change (1 : F) = ∑ _ : Fin b, (0 : F) * 1 at h
simp at h
theorem output_size_le_cost (P : MatrixAlgorithm F a b c) (hb : 1 ≤ b)
(hP : P.Correct) : a * c ≤ P.cost := by
classical
let f : Fin a × Fin c → Fin P.registers := fun o => P.output o.1 o.2
have hf : Function.Injective f := P.output_injective hb hP
calc
a * c = ∑ _o : Fin a × Fin c, (1 : ℕ) := by simp
_ ≤ ∑ o : Fin a × Fin c, P.program.registerCost (f o) := by
apply Finset.sum_le_sum
intro o ho
exact P.one_le_output_registerCost hb hP o.1 o.2
_ = ∑ r ∈ Finset.univ.image f, P.program.registerCost r := by
rw [Finset.sum_image]
exact fun _ _ _ _ h => hf h
_ ≤ ∑ r, P.program.registerCost r :=
Finset.sum_le_sum_of_subset (Finset.subset_univ _)
_ = P.cost := P.program.sum_registerCost
end MatrixAlgorithm
theorem rectangularAdmissibleExponent_two_le {F : Type*} [Field F] {k τ : ℝ}
(hτ : RectangularAdmissibleExponent F k τ) : 2 ≤ τ := by
by_contra hneg
have hτlt : τ < 2 := lt_of_not_ge hneg
let ε : ℝ := (2 - τ) / 2
have hε : 0 < ε := by dsimp [ε]; linarith
obtain ⟨C, hC, hbound⟩ := hτ ε hε
obtain ⟨n, hn⟩ := exists_nat_gt (max (C ^ ε⁻¹) 1)
have hnreal : 1 < (n : ℝ) := lt_of_le_of_lt (le_max_right _ _) hn
have hnpos : 0 < (n : ℝ) := lt_trans zero_lt_one hnreal
have hn1 : 1 ≤ n := (Nat.one_le_cast (α := ℝ)).mp hnreal.le
have hpow : C < (n : ℝ) ^ ε :=
(Real.rpow_inv_lt_iff_of_pos hC.le (Nat.cast_nonneg n) hε).mp
(lt_of_le_of_lt (le_max_left _ _) hn)
obtain ⟨P, hP, hcost⟩ := hbound n hn1
have hlower : (n : ℝ) ^ (2 : ℕ) ≤ P.cost := by
have h : n ^ 2 ≤ P.cost := by
simpa [pow_two] using P.output_size_le_cost (one_le_innerSize hn1 k) hP
exact_mod_cast h
have hstrict : (n : ℝ) ^ (2 : ℕ) < (n : ℝ) ^ (2 : ℕ) := calc
(n : ℝ) ^ (2 : ℕ) ≤ C * (n : ℝ) ^ (τ + ε) := hlower.trans hcost
_ < (n : ℝ) ^ ε * (n : ℝ) ^ (τ + ε) :=
mul_lt_mul_of_pos_right hpow (Real.rpow_pos_of_pos hnpos _)
_ = (n : ℝ) ^ (2 : ℕ) := by
rw [← Real.rpow_add hnpos]
have he : ε + (τ + ε) = 2 := by dsimp [ε]; ring
rw [he]
norm_num
exact (lt_irrefl _ hstrict)
theorem rectangularAdmissibleExponent_bddBelow (F : Type*) [Field F] (k : ℝ) :
BddBelow {τ : ℝ | RectangularAdmissibleExponent F k τ} :=
⟨2, fun _ h => rectangularAdmissibleExponent_two_le h⟩
theorem rectangularOmega_le_of_admissibleExponent {F : Type*} [Field F] {k τ : ℝ}
(hτ : RectangularAdmissibleExponent F k τ) : rectangularOmega F k ≤ τ :=
csInf_le (rectangularAdmissibleExponent_bddBelow F k) hτ
theorem admissibleExponent_iff_rectangular_one (F : Type*) [Field F] (τ : ℝ) :
AdmissibleExponent F τ ↔ RectangularAdmissibleExponent F 1 τ := by
constructor
· intro h ε hε
obtain ⟨C, hC, hbound⟩ := h ε hε
refine ⟨C, hC, ?_⟩
intro n hn
rw [innerSize_one]
exact hbound n hn
· intro h ε hε
obtain ⟨C, hC, hbound⟩ := h ε hε
refine ⟨C, hC, ?_⟩
intro n hn
have hnBound := hbound n hn
rw [innerSize_one] at hnBound
exact hnBound
theorem admissibleExponent_two_le {F : Type*} [Field F] {τ : ℝ}
(hτ : AdmissibleExponent F τ) : 2 ≤ τ :=
rectangularAdmissibleExponent_two_le ((admissibleExponent_iff_rectangular_one F τ).mp hτ)
theorem admissibleExponent_bddBelow (F : Type*) [Field F] :
BddBelow {τ : ℝ | AdmissibleExponent F τ} :=
⟨2, fun _ h => admissibleExponent_two_le h⟩
theorem omega_le_of_admissibleExponent {F : Type*} [Field F] {τ : ℝ}
(hτ : AdmissibleExponent F τ) : omega F ≤ τ :=
csInf_le (admissibleExponent_bddBelow F) hτ
@[simp] theorem rectangularOmega_one (F : Type*) [Field F] :
rectangularOmega F 1 = omega F := by
unfold rectangularOmega omega
congr 1
ext τ
exact (admissibleExponent_iff_rectangular_one F τ).symm
end
variable {F : Type*} [Field F]
namespace Expression
variable {Input : Type*}
def sumFin : {n : ℕ} → (Fin n → Expression F Input) → Expression F Input
| 0, _ => .constant 0
| n + 1, f => .add (f 0) (sumFin (fun i : Fin n => f i.succ))
theorem sumFin_eval {n : ℕ} (f : Fin n → Expression F Input) (inputs : Input → F) :
(sumFin f).eval inputs = ∑ i, (f i).eval inputs := by
induction n with
| zero => simp [sumFin, eval]
| succ n ih => simp [sumFin, eval, ih, Fin.sum_univ_succ]
theorem sumFin_cost {n : ℕ} (f : Fin n → Expression F Input) :
(sumFin f).cost = (∑ i, (f i).cost) + n := by
induction n with
| zero => simp [sumFin, cost]
| succ n ih =>
simp only [sumFin, cost, ih, Fin.sum_univ_succ]
omega
end Expression
def naiveEntry {a b c : ℕ} (i : Fin a) (k : Fin c) : Expression F (MatrixInput a b c) :=
Expression.sumFin fun j : Fin b =>
.mul (.input (.inl (i, j))) (.input (.inr (j, k)))
theorem naiveEntry_eval {a b c : ℕ} (i : Fin a) (k : Fin c)
(A : Matrix (Fin a) (Fin b) F) (B : Matrix (Fin b) (Fin c) F) :
(naiveEntry i k).eval (matrixInputs A B) = ∑ j, A i j * B j k := by
simp [naiveEntry, Expression.sumFin_eval, Expression.eval, matrixInputs]
@[simp] theorem naiveEntry_cost {a b c : ℕ} (i : Fin a) (k : Fin c) :
(naiveEntry (F := F) (b := b) i k).cost = 2 * b := by
simp [naiveEntry, Expression.sumFin_cost, Expression.cost, two_mul]
def naiveAlgorithm (a b c : ℕ) : MatrixAlgorithm F a b c :=
let p := Expression.compileFamily (fun ik : Fin a × Fin c => naiveEntry (b := b) ik.1 ik.2)
{ registers := p.registers
program := p.program
output := fun i k => p.output (i, k) }
theorem naiveAlgorithm_correct (a b c : ℕ) : (naiveAlgorithm (F := F) a b c).Correct := by
apply (MatrixAlgorithm.correct_iff_entries _).2
intro A B i k
let p := Expression.compileFamily (fun ik : Fin a × Fin c => naiveEntry (F := F) (b := b) ik.1 ik.2)
change p.program.eval (matrixInputs A B) (p.output (i, k)) = _
rw [p.correct]
exact naiveEntry_eval i k A B
@[simp] theorem naiveAlgorithm_cost (a b c : ℕ) :
(naiveAlgorithm (F := F) a b c).cost = 2 * a * b * c := by
let p := Expression.compileFamily (fun ik : Fin a × Fin c => naiveEntry (F := F) (b := b) ik.1 ik.2)
change p.program.cost = _
rw [p.cost_eq]
simp only [naiveEntry_cost, Finset.sum_const, Finset.card_univ,
Fintype.card_prod, Fintype.card_fin, nsmul_eq_mul, Nat.cast_id]
ring
theorem naiveAlgorithm_cost_le (a b c : ℕ) :
(naiveAlgorithm (F := F) a b c).cost ≤ 2 * a * b * c :=
(naiveAlgorithm_cost a b c).le
theorem admissibleExponent_three : AdmissibleExponent F 3 := by
intro ε hε
refine ⟨2, by norm_num, ?_⟩
intro n hn
refine ⟨naiveAlgorithm n n n, naiveAlgorithm_correct n n n, ?_⟩
rw [naiveAlgorithm_cost]
have hnR : (1 : ℝ) ≤ (n : ℝ) := by exact_mod_cast hn
have hpow : (n : ℝ) ^ (3 : ℝ) ≤ (n : ℝ) ^ (3 + ε) :=
Real.rpow_le_rpow_of_exponent_le hnR (le_add_of_nonneg_right hε.le)
calc
((2 * n * n * n : ℕ) : ℝ) = 2 * (n : ℝ) ^ (3 : ℝ) := by
calc
((2 * n * n * n : ℕ) : ℝ) = 2 * (n : ℝ) ^ (3 : ℕ) := by
push_cast
ring
_ = 2 * (n : ℝ) ^ (3 : ℝ) :=
congrArg (fun t : ℝ => 2 * t) (Real.rpow_natCast (n : ℝ) 3).symm
_ ≤ 2 * (n : ℝ) ^ (3 + ε) := mul_le_mul_of_nonneg_left hpow (by norm_num)
theorem admissibleExponent_nonempty : Set.Nonempty {τ : ℝ | AdmissibleExponent F τ} :=
⟨3, admissibleExponent_three⟩
end MatrixMultiplication.Arithmetic
end
noncomputable section
namespace MatrixMultiplication.Arithmetic
variable {F : Type*} [Field F]
theorem AdmissibleExponent.mono {τ σ : ℝ} (hτ : AdmissibleExponent F τ)
(hτσ : τ ≤ σ) : AdmissibleExponent F σ := by
intro ε hε
obtain ⟨C, hC, hbound⟩ := hτ ε hε
refine ⟨C, hC, ?_⟩
intro n hn
obtain ⟨P, hP, hcost⟩ := hbound n hn
refine ⟨P, hP, hcost.trans ?_⟩
apply mul_le_mul_of_nonneg_left _ hC.le
exact Real.rpow_le_rpow_of_exponent_le (by exact_mod_cast hn)
(add_le_add hτσ le_rfl)
theorem omega_two_le : 2 ≤ omega F :=
le_csInf admissibleExponent_nonempty (fun _ hτ => admissibleExponent_two_le hτ)
theorem omega_nonneg : 0 ≤ omega F := le_trans (by norm_num) omega_two_le
theorem omega_le_three : omega F ≤ 3 :=
omega_le_of_admissibleExponent admissibleExponent_three
theorem omega_admissibleExponent : AdmissibleExponent F (omega F) := by
intro ε hε
have hhalf : 0 < ε / 2 := half_pos hε
obtain ⟨τ, hτ, hclose⟩ := exists_lt_of_csInf_lt admissibleExponent_nonempty
(show sInf {σ : ℝ | AdmissibleExponent F σ} < omega F + ε / 2 from
lt_add_of_pos_right (omega F) hhalf)
obtain ⟨C, hC, hbound⟩ := hτ (ε / 2) hhalf
refine ⟨C, hC, ?_⟩
intro n hn
obtain ⟨P, hP, hcost⟩ := hbound n hn
refine ⟨P, hP, hcost.trans ?_⟩
apply mul_le_mul_of_nonneg_left _ hC.le
exact Real.rpow_le_rpow_of_exponent_le (by exact_mod_cast hn) (by linarith)
theorem admissibleExponent_iff_omega_le {τ : ℝ} :
AdmissibleExponent F τ ↔ omega F ≤ τ :=
⟨omega_le_of_admissibleExponent, omega_admissibleExponent.mono⟩
theorem RectangularAdmissibleExponent.mono {k τ σ : ℝ}
(hτ : RectangularAdmissibleExponent F k τ) (hτσ : τ ≤ σ) :
RectangularAdmissibleExponent F k σ := by
intro ε hε
obtain ⟨C, hC, hbound⟩ := hτ ε hε
refine ⟨C, hC, ?_⟩
intro n hn
obtain ⟨P, hP, hcost⟩ := hbound n hn
refine ⟨P, hP, hcost.trans ?_⟩
apply mul_le_mul_of_nonneg_left _ hC.le
exact Real.rpow_le_rpow_of_exponent_le (by exact_mod_cast hn)
(add_le_add hτσ le_rfl)
theorem rectangularAdmissibleExponent_of_uniform_costs {k τ C : ℝ} (hC : 0 < C)
(hbound : ∀ n : ℕ, 1 ≤ n → ∃ P : MatrixAlgorithm F n (innerSize n k) n,
P.Correct ∧ (P.cost : ℝ) ≤ C * (n : ℝ) ^ τ) :
RectangularAdmissibleExponent F k τ := by
intro ε hε
refine ⟨C, hC, ?_⟩
intro n hn
obtain ⟨P, hP, hcost⟩ := hbound n hn
refine ⟨P, hP, hcost.trans ?_⟩
apply mul_le_mul_of_nonneg_left _ hC.le
exact Real.rpow_le_rpow_of_exponent_le (by exact_mod_cast hn)
(le_add_of_nonneg_right hε.le)
theorem rectangularAdmissibleExponent_naive (k : ℝ) :
RectangularAdmissibleExponent F k (2 + max k 0) := by
apply rectangularAdmissibleExponent_of_uniform_costs (C := 4) (by norm_num)
intro n hn
refine ⟨naiveAlgorithm n (innerSize n k) n,
naiveAlgorithm_correct n (innerSize n k) n, ?_⟩
have hnpos : 0 < (n : ℝ) := by exact_mod_cast (lt_of_lt_of_le Nat.zero_lt_one hn)
have hinner : (innerSize n k : ℝ) ≤ 2 * (n : ℝ) ^ max k 0 :=
(Nat.cast_le.mpr (innerSize_mono hn (le_max_left k 0))).trans
(innerSize_cast_le hn (le_max_right k 0))
rw [naiveAlgorithm_cost]
push_cast
calc
2 * (n : ℝ) * innerSize n k * n = 2 * (n : ℝ) ^ 2 * innerSize n k := by ring
_ ≤ 2 * (n : ℝ) ^ 2 * (2 * (n : ℝ) ^ max k 0) :=
mul_le_mul_of_nonneg_left hinner (by positivity)
_ = 4 * (n : ℝ) ^ (2 + max k 0) := by
rw [Real.rpow_add hnpos]
norm_num
ring
theorem rectangularAdmissibleExponent_nonempty (k : ℝ) :
Set.Nonempty {τ : ℝ | RectangularAdmissibleExponent F k τ} :=
⟨2 + max k 0, rectangularAdmissibleExponent_naive k⟩
theorem rectangularOmega_two_le (k : ℝ) : 2 ≤ rectangularOmega F k :=
le_csInf (rectangularAdmissibleExponent_nonempty k)
(fun _ hτ => rectangularAdmissibleExponent_two_le hτ)
theorem rectangularOmega_admissibleExponent (k : ℝ) :
RectangularAdmissibleExponent F k (rectangularOmega F k) := by
intro ε hε
have hhalf : 0 < ε / 2 := half_pos hε
obtain ⟨τ, hτ, hclose⟩ := exists_lt_of_csInf_lt (rectangularAdmissibleExponent_nonempty k)
(show sInf {σ : ℝ | RectangularAdmissibleExponent F k σ} <
rectangularOmega F k + ε / 2 from lt_add_of_pos_right (rectangularOmega F k) hhalf)
obtain ⟨C, hC, hbound⟩ := hτ (ε / 2) hhalf
refine ⟨C, hC, ?_⟩
intro n hn
obtain ⟨P, hP, hcost⟩ := hbound n hn
refine ⟨P, hP, hcost.trans ?_⟩
apply mul_le_mul_of_nonneg_left _ hC.le
exact Real.rpow_le_rpow_of_exponent_le (by exact_mod_cast hn) (by linarith)
theorem rectangularAdmissibleExponent_iff_omega_le {k τ : ℝ} :
RectangularAdmissibleExponent F k τ ↔ rectangularOmega F k ≤ τ :=
⟨rectangularOmega_le_of_admissibleExponent, (rectangularOmega_admissibleExponent k).mono⟩
theorem rectangularOmega_mono {k l : ℝ} (hkl : k ≤ l) :
rectangularOmega F k ≤ rectangularOmega F l :=
rectangularOmega_le_of_admissibleExponent
((rectangularOmega_admissibleExponent l).mono_aspect hkl)
@[simp] theorem rectangularOmega_zero : rectangularOmega F 0 = 2 := by
apply le_antisymm _ (rectangularOmega_two_le 0)
apply rectangularOmega_le_of_admissibleExponent
simpa using (rectangularAdmissibleExponent_naive (F := F) 0)
theorem complexAlpha_set_nonempty :
Set.Nonempty {k : ℝ | k ∈ Set.Icc 0 1 ∧ rectangularOmega ℂ k = 2} :=
⟨0, ⟨by norm_num, by norm_num⟩, rectangularOmega_zero⟩
theorem complexAlpha_set_bddAbove :
BddAbove {k : ℝ | k ∈ Set.Icc 0 1 ∧ rectangularOmega ℂ k = 2} :=
⟨1, fun _ h => h.1.2⟩
theorem le_complexAlpha {k : ℝ} (hk : k ∈ Set.Icc 0 1)
(hω : rectangularOmega ℂ k = 2) : k ≤ complexAlpha :=
le_csSup complexAlpha_set_bddAbove ⟨hk, hω⟩
theorem complexAlpha_le_one : complexAlpha ≤ 1 :=
csSup_le complexAlpha_set_nonempty (fun _ h => h.1.2)
theorem complexAlpha_nonneg : 0 ≤ complexAlpha :=
le_complexAlpha ⟨le_refl 0, by norm_num⟩ rectangularOmega_zero
end MatrixMultiplication.Arithmetic
end
end MatrixAllFields
end OAI