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import OAI.Combinatorics.HadwigerCounterexample.SingletonPhaseTests
namespace OAI
/-! # Additional Probe Bounds -/
noncomputable section
namespace HadwigerCounterexample
open Matrix Module Submodule Function Finset
open scoped BigOperators
variable {I J K : Type} [Fintype I] [Fintype J] [Fintype K]
private def moreMatrix {r : ℕ} (A : Mat I (Fin r)) (v : Vec I) : Mat I (Fin (r+1)) :=
Matrix.of (fun i => Fin.cons (v i) (A i))
omit [Fintype I] in
private theorem moreMatrix_act {r : ℕ} (A : Mat I (Fin r)) (v : Vec I)
(x : Vec (Fin (r+1))) :
moreMatrix A v *ᵥ x=x 0 • v + A *ᵥ (fun i => x i.succ) := by
funext i; simp only [Matrix.mulVec,dotProduct,moreMatrix,Matrix.of_apply,
Fin.sum_univ_succ,Pi.add_apply,Pi.smul_apply,smul_eq_mul,Fin.cons_zero,Fin.cons_succ]
congr 1; exact mul_comm _ _
omit [Fintype I] in
private theorem moreMatrix_inj {r : ℕ} (A : Mat I (Fin r)) (v : Vec I)
(ha : Injective A.mulVec) (h : v∉colSp A) :
Injective (moreMatrix A v).mulVec := by
rw [← Matrix.coe_mulVecLin,← LinearMap.ker_eq_bot, Matrix.ker_mulVecLin_eq_bot_iff]
intro x hx
rw [moreMatrix_act] at hx
let b (i : Fin r) := x i.succ
rcases bit_cases (x 0) with he|he
· have hh : b=0 := by
apply ha
rw [he,zero_smul,zero_add] at hx
exact hx.trans (Matrix.mulVec_zero _).symm
funext i
refine Fin.cases he (fun k => ?_) i
exact congr_fun hh k
· rw [he,one_smul] at hx
have heq : v=A *ᵥ b := add_right_cancel (hx.trans (char_two _).symm)
exact (h ⟨b,heq.symm⟩).elim
omit [Fintype J] in
private theorem moreMatrix_mul {r} (B : Mat J I) (A : Mat I (Fin r)) (v) :
B*moreMatrix A v=moreMatrix (B*A) (B *ᵥ v) := by
ext i j
refine Fin.cases ?_ (fun j => ?_) j
· rfl
simp only [moreMatrix,Matrix.mul_apply,Matrix.of_apply,Fin.cons_succ]
variable {p : Shape} {n N r : ℕ} {T : Cov p N}
variable {q : Place p → ℕ}
private def growFmt (q : Place p→ℕ) (z : Place p) := fun i =>
q i+(if i=z then 1 else 0)
private theorem grow_sum (q : Place p→ℕ) (z : Place p) :
ctot p (growFmt (p:=p) q z)=ctot p q+1 := by simp [growFmt,ctot,Finset.sum_add_distrib]
private def growing (A : DTuple (p:=p) q N) (z : Place p) (v : Vec (Fin N)) :
DTuple (p:=p) (growFmt (p:=p) q z) N := fun i => by
change Mat (Fin N) (Fin (q i+ if i=z then 1 else 0))
by_cases h : i=z
· rw [ite_eq_left h]; exact moreMatrix (A i) v
rw [ite_eq_right h]; exact A i
private theorem castMat_inj {r n m : ℕ} (e : r=n)
(A : Mat (Fin m) (Fin r)) (h : Injective A.mulVec) :
Injective (cast (show Mat (Fin m) (Fin r)=Mat (Fin m) (Fin n) from congrArg (fun t => Mat (Fin m) (Fin t)) e) A).mulVec := by
subst n
exact h
private theorem castMat_prod {r n m : ℕ} (e : r=n)
(A : Mat (Fin m) (Fin r)) (B : Mat (Fin m) (Fin m)) :
B*(cast (show Mat (Fin m) (Fin r)=Mat (Fin m) (Fin n) from congrArg (fun t => Mat (Fin m) (Fin t)) e) A) =
cast (show Mat (Fin m) (Fin r)=Mat (Fin m) (Fin n) from congrArg (fun t => Mat (Fin m) (Fin t)) e) (B*A) := by
subst n; rfl
private theorem growth_inj (A : DTuple (p:=p) q N) (z : Place p) (v : Vec (Fin N))
(hv : v∉colSp (A z)) (h : ∀ i, Injective (A i).mulVec) :
∀ i,Injective (growing A z v i).mulVec := by
intro i
by_cases he : i=z
· subst i
simp [growing,growFmt]
apply castMat_inj _ (moreMatrix (A z) v) (moreMatrix_inj (A z) v (h z) hv)
simp
simp [growing,growFmt,he]
apply castMat_inj _ (A i) (h i)
simp [he]
private theorem growth_value (A : DTuple (p:=p) q N) (z : Place p) (v : Vec (Fin N))
(x : UnitType p n N) (S : Party) :
thermal p x S (growing A z v)=growing (thermal p x S A) z (heat p x S z *ᵥ v) := by
funext i
by_cases he : i=z
· subst i
simp [thermal,growing,growFmt]
rw [←moreMatrix_mul]
apply castMat_prod
simp
simp [thermal,growing,growFmt,he]
apply castMat_prod
simp [he]
theorem column_observe (A : DTuple (p:=p) q N) (z : Place p) (j : Fin (q z))
(x : UnitType p n N) (S : Party) :
heat p x S z *ᵥ (A z).col j=(thermal p x S A z).col j := rfl
namespace Bazaar
variable (s : Bazaar p n r T)
abbrev Catalog (p : Shape) {N} (T : Cov p N) (r : ℕ) (q : Place p→ℕ) :=
(M : Atlas p r T) → Batch M N → Finset (DTuple (p:=p) q N)
def atList (s : Bazaar p n r T) (S : Party) (j : Bool)
(A : DTuple (p:=p) q N) (F : Catalog p T r q) (x : UnitType p n N) :=
let M := s.ix x
thermal p x S A∈ F M (s.bag M j x)
def probed (p : Shape) {N} {q : Place p→ℕ} (A : DTuple (p:=p) q N) : Cov p N :=
fun z => colSp (A z)
theorem extend_probe (w : Wgt (UnitType p n N)) (S : Party) (j : Bool) {k : ℕ}
(A : DTuple (p:=p) q N) (hq : ctot p q=k)
(h : ∀ i, Injective (A i).mulVec)
(F : Catalog p T r q) (hF : ∀ M Z,(↑(F M Z).card:ℝ) ≤ bp (0.51*k*N))
(G : Atlas p r T) (hg : ¬ offsetCov G ≤ probed p A)
(hb : ∀ M Z,(↑(s.bids w S j G M Z).card:ℝ) ≤ bp (0.51*N)) :
∃ (q : Place p→ℕ) (A' : DTuple (p:=p) q N)
(F' : Catalog p T r q), ctot p q=k+1 ∧
(∀ i, Injective (A' i).mulVec) ∧
(∀ M Z,(↑(F' M Z).card:ℝ) ≤ bp (0.51*(k+1)*N)) ∧
∀ x,s.atList S j A F x → s.frequent w S j G (s.ix x) x →
s.atList S j A' F' x := by
classical
obtain ⟨z,i,hg⟩ :
∃ (z : Place p) (i : Fin (breadth G z)),(src G z).col i∉colSp (A z) := by
by_contra! hh
apply hg
intro z
change colSp (src G z) ≤ _
rw [colSp,range_mulVecLin]
exact Submodule.span_le.mpr (Set.range_subset_iff.mpr (hh z))
let q' := growFmt (p:=p) q z
let v := (src G z).col i
let f (M Z) : Finset (DTuple (p:=p) q' N) :=
((F M Z) ×ˢ (s.bids w S j G M Z)).image
(fun a => growing a.1 z ((a.2 z).col i))
refine ⟨q',growing A z v, f,(grow_sum q z).trans (by rw [hq]),
growth_inj A z v hg h,fun M Z => ?_,fun x hx hi => ?_⟩
· have he := bp_pos (0.51*(k:ℝ)*N)
have h1 :
(↑(f M Z).card:ℝ) ≤ (↑(F M Z).card:ℝ)*(↑(s.bids w S j G M Z).card:ℝ) := by
exact_mod_cast (show (f M Z).card ≤ _*_ from
Finset.card_image_le.trans_eq (Finset.card_product ..))
apply (h1.trans (mul_le_mul (hF M Z) (hb M Z) (Nat.cast_nonneg _) he.le)).trans_eq
rw [←bp_add]; congr 1; ring
· rw [atList,growth_value]
refine Finset.mem_image.mpr ⟨(thermal p x S A,thermal p x S (src G)),?_,?_⟩
· exact Finset.mem_product.mpr ⟨hx,(s.bids_mem ..).mp hi⟩
· change growing _ _ _ = _
rw [show heat p x S z *ᵥ v=_ from column_observe (src G) z i x S]
end Bazaar
end HadwigerCounterexample
end
end OAI