openAI-math-dataset / lean /OAI /Probability /RandomSAT /CenterComparison.lean
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import OAI.Probability.RandomSAT.Transfer
namespace OAI
/-!
Partition interpolation and concentration yield summable-error comparisons
for centers of two blocks and of neighboring sizes.
-/
namespace FixedClauseThreshold
open Finset
noncomputable section
attribute [local instance] Classical.propDecidable
theorem auxiliary_interpolation_center_lower {r s k m : ℕ} (hk : 3 ≤ k)
(hr : k + 1 ≤ r) (hs : k + 1 ≤ s)
(hrrep : 2 * repeatPairs k ≤ r) (hsrep : 2 * repeatPairs k ≤ s)
(hrerr : concentrationError r k ≤ 1 / 2) (hserr : concentrationError s k ≤ 1 / 2)
(hm : (m : ℝ) ≤ (capMultiplier k : ℝ) * ((r : ℝ) + s))
(hgapr : (m : ℝ) * ((r : ℝ) / (r + s)) + 2 * fluctuationWindow r k ≤ (r : ℝ) * center r k)
(hgaps : (m : ℝ) * ((s : ℝ) / (r + s)) + 2 * fluctuationWindow s k ≤ (s : ℝ) * center s k) :
(transferLower k)^2 * (1 - samplingError r k - samplingError s k) ≤
auxiliaryProbability (r + s) k m := by
have hr0 : 0 < r := by omega
have hs0 : 0 < s := by omega
have hr' : (0 : ℝ) < r := by exact_mod_cast hr0
have hs' : (0 : ℝ) < s := by exact_mod_cast hs0
let p : ℝ := (r : ℝ) / (r + s)
have hp0 : 0 ≤ p := by dsimp [p]; positivity
have hp1 : p ≤ 1 := by
dsimp [p]
apply (div_le_one (by positivity : (0 : ℝ) < r + s)).mpr
linarith
have hpq : 1 - p = (s : ℝ) / (r + s) := by dsimp [p]; field_simp; ring
have hwr := fluctuationWindow_pos (k := k) hr0
have hws := fluctuationWindow_pos (k := k) hs0
have hpoint : ∀ j ≤ m,
(transferLower k)^2 * (1 - ((j : ℝ) - m * p)^2 / (fluctuationWindow r k)^2 -
((j : ℝ) - m * p)^2 / (fluctuationWindow s k)^2) ≤
auxiliaryProbability r k j * auxiliaryProbability s k (m - j) := by
intro j hj
apply product_lower_two_deviations (transferLower_pos k).le (by positivity) (by positivity)
(auxiliaryProbability_nonneg r k j) (auxiliaryProbability_nonneg s k (m - j))
· intro hdev
apply auxiliaryProbability_center_lower hk hr hrrep hrerr
have hsq : ((j : ℝ) - m * p)^2 < (fluctuationWindow r k)^2 :=
(div_lt_one (sq_pos_of_pos hwr)).mp hdev
by_contra hgap
have hdiff : fluctuationWindow r k < (j : ℝ) - m * p := by
change (m : ℝ) * p + 2 * fluctuationWindow r k ≤ (r : ℝ) * center r k at hgapr
linarith
nlinarith
· intro hdev
apply auxiliaryProbability_center_lower hk hs hsrep hserr
have hsq : ((j : ℝ) - m * p)^2 < (fluctuationWindow s k)^2 :=
(div_lt_one (sq_pos_of_pos hws)).mp hdev
rw [← hpq] at hgaps
rw [Nat.cast_sub hj]
by_contra hgap
have hdiff : fluctuationWindow s k < -((j : ℝ) - m * p) := by linarith
nlinarith
have hmean := binomialMean_mono hp0 hp1 hpoint
rw [binomialMean_const_mul, binomialMean_sub, binomialMean_sub, binomialMean_const,
binomialMean_div_const, binomialMean_div_const, binomialMean_centered_square] at hmean
apply le_trans _ (hmean.trans (auxiliary_interpolation hr0 hs0 m))
apply mul_le_mul_of_nonneg_left _ (sq_nonneg _)
have hmp : (m : ℝ) * p ≤ (capMultiplier k : ℝ) * r := by
have h := mul_le_mul_of_nonneg_right hm hp0
have he : ((capMultiplier k : ℝ) * ((r : ℝ) + s)) * p =
(capMultiplier k : ℝ) * r := by dsimp [p]; field_simp
simpa only [he] using h
have hmq : (m : ℝ) * (1 - p) ≤ (capMultiplier k : ℝ) * s := by
have h := mul_le_mul_of_nonneg_right hm (sub_nonneg.mpr hp1)
have he : ((capMultiplier k : ℝ) * ((r : ℝ) + s)) * (1 - p) =
(capMultiplier k : ℝ) * s := by rw [hpq]; field_simp
simpa only [he] using h
have hvr : (m : ℝ) * p * (1 - p) ≤ (capMultiplier k : ℝ) * r := by
have h := mul_le_mul_of_nonneg_left (show 1 - p ≤ 1 by linarith)
(mul_nonneg (Nat.cast_nonneg m) hp0)
nlinarith
have hvs : (m : ℝ) * p * (1 - p) ≤ (capMultiplier k : ℝ) * s := by
have h := mul_le_mul_of_nonneg_left hp1
(mul_nonneg (Nat.cast_nonneg m) (sub_nonneg.mpr hp1))
nlinarith
have hfr := div_le_div_of_nonneg_right hvr (sq_nonneg (fluctuationWindow r k))
have hfs := div_le_div_of_nonneg_right hvs (sq_nonneg (fluctuationWindow s k))
unfold samplingError
linarith
def densityWindow (n k : ℕ) : ℝ := (n : ℝ)^(-delta k)
theorem densityWindow_pos {n k : ℕ} (hn : 0 < n) : 0 < densityWindow n k :=
Real.rpow_pos_of_pos (by exact_mod_cast hn) _
theorem fluctuationWindow_eq_mul {n k : ℕ} (hn : 0 < n) :
fluctuationWindow n k = (n : ℝ) * densityWindow n k := by
unfold fluctuationWindow densityWindow
rw [sub_eq_add_neg, Real.rpow_add (by exact_mod_cast hn), Real.rpow_one]
theorem fluctuationWindow_one_le {n k : ℕ} (hk : 3 ≤ k) (hn : 0 < n) :
1 ≤ fluctuationWindow n k := by
apply Real.one_le_rpow (by exact_mod_cast hn : (1 : ℝ) ≤ n)
have h := delta_lt_half hk
linarith
theorem densityWindow_antitone {r s k : ℕ} (hk : 3 ≤ k) (hr : 0 < r) (hrs : r ≤ s) :
densityWindow s k ≤ densityWindow r k :=
Real.rpow_le_rpow_of_nonpos (by exact_mod_cast hr) (by exact_mod_cast hrs)
(neg_nonpos.mpr (delta_pos hk).le)
theorem densityWindow_tendsto (k : ℕ) (hk : 3 ≤ k) :
Filter.Tendsto (fun n : ℕ => densityWindow n k) Filter.atTop (nhds 0) :=
(tendsto_rpow_neg_atTop (delta_pos hk)).comp (tendsto_natCast_atTop_atTop (R := ℝ))
theorem concentrationError_tendsto (k : ℕ) (hk : 3 ≤ k) :
Filter.Tendsto (fun n : ℕ => concentrationError n k) Filter.atTop (nhds 0) := by
have hη : 0 < eta k := by rw [eta_eq_twice_delta]; positivity [delta_pos hk]
have ht := (tendsto_rpow_neg_atTop hη).comp (tendsto_natCast_atTop_atTop (R := ℝ))
simpa only [concentrationError, Function.comp_apply, mul_zero] using ht.const_mul (varianceConstant k)
theorem samplingError_identity {n k : ℕ} (hn : 0 < n) :
samplingError n k = (capMultiplier k : ℝ) * (n : ℝ)^(-(1 - 2 * delta k)) := by
have hn' : (0 : ℝ) < n := by exact_mod_cast hn
unfold samplingError fluctuationWindow
rw [← Real.rpow_two ((n : ℝ)^(1 - delta k)), ← Real.rpow_mul hn'.le]
have he : -(1 - 2 * delta k) = 1 - (1 - delta k) * 2 := by ring
rw [he, Real.rpow_sub hn', Real.rpow_one]
ring
theorem samplingError_tendsto (k : ℕ) (hk : 3 ≤ k) :
Filter.Tendsto (fun n : ℕ => samplingError n k) Filter.atTop (nhds 0) := by
have hd : 0 < 1 - 2 * delta k := by linarith [delta_lt_half hk]
have ht := (tendsto_rpow_neg_atTop hd).comp (tendsto_natCast_atTop_atTop (R := ℝ))
have ht' : Filter.Tendsto (fun n : ℕ => (capMultiplier k : ℝ) * (n : ℝ)^(-(1 - 2 * delta k)))
Filter.atTop (nhds 0) := by simpa only [Function.comp_apply, mul_zero] using ht.const_mul (capMultiplier k : ℝ)
apply ht'.congr'
filter_upwards [Filter.eventually_ge_atTop 1] with n hn
exact (samplingError_identity (k := k) (by omega)).symm
theorem fluctuationWindow_tendsto (k : ℕ) (hk : 3 ≤ k) :
Filter.Tendsto (fun n : ℕ => fluctuationWindow n k) Filter.atTop Filter.atTop := by
have hd : 0 < 1 - delta k := by linarith [delta_lt_half hk]
exact (tendsto_rpow_atTop hd).comp (tendsto_natCast_atTop_atTop (R := ℝ))
theorem center_lower_of_auxiliary_probability {n k : ℕ} (hk : 3 ≤ k) (hn : k + 1 ≤ n)
{c : ℝ} (hc0 : 0 ≤ c) (hcL : c ≤ capMultiplier k)
(hprob : concentrationError n k < auxiliaryProbability n k ⌊c * n⌋₊) :
c - 2 * densityWindow n k < center n k := by
have hn0 : 0 < n := by omega
have hn' : (0 : ℝ) < n := by exact_mod_cast hn0
have hf := Nat.floor_le (mul_nonneg hc0 hn'.le)
have hm : ⌊c * (n : ℝ)⌋₊ ≤ mainCap n k := by
have h := hf.trans (mul_le_mul_of_nonneg_right hcL hn'.le)
exact_mod_cast (show (⌊c * (n : ℝ)⌋₊ : ℝ) ≤ (mainCap n k : ℝ) by
simpa only [mainCap, Nat.cast_mul] using h)
by_contra h
have hw := fluctuationWindow_one_le (n := n) hk hn0
have he := fluctuationWindow_eq_mul (k := k) hn0
have hc : center n k + 2 * densityWindow n k ≤ c := by linarith
have hmul := mul_le_mul_of_nonneg_left hc hn'.le
have hfloor := Nat.lt_floor_add_one (c * (n : ℝ))
have hgap : (n : ℝ) * center n k + fluctuationWindow n k ≤ ⌊c * (n : ℝ)⌋₊ := by
nlinarith
exact not_lt_of_ge (auxiliaryProbability_center_upper hk hn hm hgap) hprob
theorem center_sum_comparison_of_bounds {r s k : ℕ} (hk : 3 ≤ k)
(hr : k + 1 ≤ r) (hs : k + 1 ≤ s)
(hrrep : 2 * repeatPairs k ≤ r) (hsrep : 2 * repeatPairs k ≤ s)
(hrerr : concentrationError r k ≤ 1 / 2) (hserr : concentrationError s k ≤ 1 / 2)
(hrsample : samplingError r k ≤ 1 / 4) (hssample : samplingError s k ≤ 1 / 4)
(hNerr : concentrationError (r + s) k < (transferLower k)^2 / 2)
(hlow : 2 * densityWindow (min r s) k ≤ min (center r k) (center s k)) :
min (center r k) (center s k) - 4 * densityWindow (min r s) k ≤ center (r + s) k := by
have hr0 : 0 < r := by omega
have hs0 : 0 < s := by omega
have hu0 : 0 < min r s := lt_min hr0 hs0
have hr' : (0 : ℝ) < r := by exact_mod_cast hr0
have hs' : (0 : ℝ) < s := by exact_mod_cast hs0
have hN' : (0 : ℝ) < (r : ℝ) + s := by positivity
let c := min (center r k) (center s k) - 2 * densityWindow (min r s) k
have hc0 : 0 ≤ c := sub_nonneg.mpr hlow
have hcL : c ≤ capMultiplier k := by
have hh := (min_le_left (center r k) (center s k)).trans (center_le_capMultiplier (by omega) hr0)
dsimp [c]
have hp := (densityWindow_pos (k := k) hu0).le
linarith
have hcr : c + 2 * densityWindow r k ≤ center r k := by
have hd := densityWindow_antitone hk hu0 (min_le_left r s)
have hh := min_le_left (center r k) (center s k)
dsimp [c]
linarith
have hcs : c + 2 * densityWindow s k ≤ center s k := by
have hd := densityWindow_antitone hk hu0 (min_le_right r s)
have hh := min_le_right (center r k) (center s k)
dsimp [c]
linarith
let m := ⌊c * ((r : ℝ) + s)⌋₊
have hm : (m : ℝ) ≤ c * ((r : ℝ) + s) := Nat.floor_le (mul_nonneg hc0 hN'.le)
have hmr : (m : ℝ) * ((r : ℝ) / (r + s)) ≤ c * r := by
have hh := mul_le_mul_of_nonneg_right hm (show 0 ≤ (r : ℝ) / (r + s) by positivity)
have he : c * ((r : ℝ) + s) * ((r : ℝ) / (r + s)) = c * r := by field_simp
rwa [he] at hh
have hms : (m : ℝ) * ((s : ℝ) / (r + s)) ≤ c * s := by
have hh := mul_le_mul_of_nonneg_right hm (show 0 ≤ (s : ℝ) / (r + s) by positivity)
have he : c * ((r : ℝ) + s) * ((s : ℝ) / (r + s)) = c * s := by field_simp
rwa [he] at hh
have hprob := auxiliary_interpolation_center_lower hk hr hs hrrep hsrep hrerr hserr
(hm.trans (mul_le_mul_of_nonneg_right hcL hN'.le))
(show (m : ℝ) * ((r : ℝ) / (r + s)) + 2 * fluctuationWindow r k ≤ (r : ℝ) * center r k by
rw [fluctuationWindow_eq_mul hr0]
have hh := mul_le_mul_of_nonneg_left hcr hr'.le
nlinarith)
(show (m : ℝ) * ((s : ℝ) / (r + s)) + 2 * fluctuationWindow s k ≤ (s : ℝ) * center s k by
rw [fluctuationWindow_eq_mul hs0]
have hh := mul_le_mul_of_nonneg_left hcs hs'.le
nlinarith)
have hhalf : (transferLower k)^2 / 2 ≤ auxiliaryProbability (r + s) k m := by
have hh := mul_le_mul_of_nonneg_left (show (1 / 2 : ℝ) ≤ 1 - samplingError r k - samplingError s k by linarith)
(sq_nonneg (transferLower k))
nlinarith
have hcN := center_lower_of_auxiliary_probability hk (by omega : k + 1 ≤ r + s) hc0 hcL
(show concentrationError (r + s) k < auxiliaryProbability (r + s) k ⌊c * ((r + s : ℕ) : ℝ)⌋₊ by
simpa only [Nat.cast_add, ← show ⌊c * ((r : ℝ) + s)⌋₊ = m from rfl] using hNerr.trans_le hhalf)
have hd := densityWindow_antitone hk hu0 (show min r s ≤ r + s by omega)
dsimp [c] at hcN
linarith
def neighborFactor (k : ℕ) : ℝ := Real.exp (-2 * (capMultiplier k : ℝ))
def neighborLower (k : ℕ) : ℝ := neighborFactor k * transferLower k
theorem neighborLower_pos (k : ℕ) : 0 < neighborLower k :=
mul_pos (Real.exp_pos _) (transferLower_pos k)
@[simp] theorem auxiliaryProbability_zero (n k : ℕ) : auxiliaryProbability n k 0 = 1 := by
simp only [auxiliaryProbability, auxiliarySurvival, Function.iterate_zero, id_eq, alive_univ]
theorem neighbor_all_left {s k m : ℕ} (hs : 0 < s) :
((s : ℝ) / (s + 1))^m * auxiliaryProbability s k m ≤ auxiliaryProbability (s + 1) k m := by
have hs' : (0 : ℝ) < s := by exact_mod_cast hs
have hp0 : 0 ≤ (s : ℝ) / (s + 1) := by positivity
have hp1 : (s : ℝ) / (s + 1) ≤ 1 := by
apply (div_le_one (by positivity : (0 : ℝ) < s + 1)).mpr
linarith
have h := binomialMean_all_success hp0 hp1 m
(fun j => auxiliaryProbability s k j * auxiliaryProbability 1 k (m - j))
(fun j _ => mul_nonneg (auxiliaryProbability_nonneg _ _ _) (auxiliaryProbability_nonneg _ _ _))
simp only [Nat.sub_self, auxiliaryProbability_zero, mul_one] at h
apply h.trans
simpa only [Nat.cast_one] using (auxiliary_interpolation (k := k) hs (by omega : 0 < 1) m)
theorem neighbor_pow_lower {s k m : ℕ} (hs : 0 < s)
(hm : (m : ℝ) ≤ (capMultiplier k : ℝ) * ((s : ℝ) + 1)) :
neighborFactor k ≤ ((s : ℝ) / (s + 1))^m := by
have hs' : (1 : ℝ) ≤ s := by exact_mod_cast hs
have hN : (0 : ℝ) < s + 1 := by linarith
have hx0 : (0 : ℝ) ≤ 1 / ((s : ℝ) + 1) := by positivity
have hx : (1 : ℝ) / ((s : ℝ) + 1) ≤ 1 / 2 := by
apply (div_le_iff₀ hN).mpr
linarith
have hbase := exp_neg_two_le_one_sub hx0 hx
have he : 1 - (1 : ℝ) / ((s : ℝ) + 1) = (s : ℝ) / (s + 1) := by field_simp; ring
rw [he] at hbase
have hpow := pow_le_pow_left₀ (Real.exp_pos _).le hbase m
rw [← Real.exp_nat_mul] at hpow
apply le_trans _ hpow
apply Real.exp_le_exp.mpr
have hh := mul_le_mul_of_nonneg_right hm hx0
have he' : (capMultiplier k : ℝ) * ((s : ℝ) + 1) * (1 / ((s : ℝ) + 1)) = capMultiplier k := by field_simp
rw [he'] at hh
nlinarith
theorem center_neighbor_comparison_of_bounds {s k : ℕ} (hk : 3 ≤ k)
(hs : k + 1 ≤ s) (hsrep : 2 * repeatPairs k ≤ s)
(hserr : concentrationError s k ≤ 1 / 2)
(hNerr : concentrationError (s + 1) k < neighborLower k)
(hlow : 2 * densityWindow s k ≤ center s k)
(hwindow : (capMultiplier k : ℝ) ≤ fluctuationWindow s k) :
center s k - 4 * densityWindow s k ≤ center (s + 1) k := by
have hs0 : 0 < s := by omega
have hs' : (0 : ℝ) < s := by exact_mod_cast hs0
let c := center s k - 2 * densityWindow s k
have hc0 : 0 ≤ c := sub_nonneg.mpr hlow
have hcenter := center_le_capMultiplier (by omega : k ≤ s) hs0
have hcL : c ≤ capMultiplier k := by
have hp := (densityWindow_pos (k := k) hs0).le
dsimp [c]
linarith
let m := ⌊c * ((s : ℝ) + 1)⌋₊
have hm : (m : ℝ) ≤ c * ((s : ℝ) + 1) := Nat.floor_le (by positivity)
have hmL := hm.trans (mul_le_mul_of_nonneg_right hcL (by positivity : (0 : ℝ) ≤ (s : ℝ) + 1))
have hgap : (m : ℝ) + fluctuationWindow s k ≤ (s : ℝ) * center s k := by
have hw := fluctuationWindow_eq_mul (k := k) hs0
have he : c * ((s : ℝ) + 1) = (s : ℝ) * center s k - 2 * fluctuationWindow s k + c := by
rw [hw]
dsimp [c]
ring
rw [he] at hm
linarith
have hlocal := auxiliaryProbability_center_lower hk hs hsrep hserr hgap
have hpow := neighbor_pow_lower (k := k) hs0 hmL
have hprod := mul_le_mul hpow hlocal (transferLower_pos k).le
(pow_nonneg (by positivity : (0 : ℝ) ≤ (s : ℝ) / (s + 1)) m)
have hprob : neighborLower k ≤ auxiliaryProbability (s + 1) k m :=
hprod.trans (neighbor_all_left hs0)
have hcN := center_lower_of_auxiliary_probability hk (by omega : k + 1 ≤ s + 1) hc0 hcL
(show concentrationError (s + 1) k < auxiliaryProbability (s + 1) k ⌊c * ((s + 1 : ℕ) : ℝ)⌋₊ by
simpa only [Nat.cast_add, Nat.cast_one] using hNerr.trans_le hprob)
have hd := densityWindow_antitone hk hs0 (Nat.le_succ s)
dsimp [c] at hcN
linarith
structure CenterRegular (k n : ℕ) : Prop where
size : k + 1 ≤ n
repetition : 2 * repeatPairs k ≤ n
error : concentrationError n k ≤ 1 / 2
sampling : samplingError n k ≤ 1 / 4
sumError : concentrationError n k < (transferLower k)^2 / 2
neighborError : concentrationError n k < neighborLower k
centerLower : lowerCenterBound ≤ center n k
densitySmall : 2 * densityWindow n k ≤ lowerCenterBound
windowLarge : (capMultiplier k : ℝ) ≤ fluctuationWindow n k
theorem centerRegular_eventually (k : ℕ) (hk : 3 ≤ k) :
∀ᶠ n : ℕ in Filter.atTop, CenterRegular k n := by
have hsize : ∀ᶠ n : ℕ in Filter.atTop, k + 1 ≤ n := Filter.eventually_ge_atTop _
have hrep := (tendsto_natCast_atTop_atTop (R := ℝ)).eventually
(Filter.eventually_ge_atTop (2 * repeatPairs k))
have he := (concentrationError_tendsto k hk).eventually_lt_const (by norm_num : (0 : ℝ) < 1 / 2)
have hs := (samplingError_tendsto k hk).eventually_lt_const (by norm_num : (0 : ℝ) < 1 / 4)
have heSum := (concentrationError_tendsto k hk).eventually_lt_const
(div_pos (sq_pos_of_pos (transferLower_pos k)) (by norm_num) : (0 : ℝ) < (transferLower k)^2 / 2)
have heNeighbor := (concentrationError_tendsto k hk).eventually_lt_const (neighborLower_pos k)
have hd := (densityWindow_tendsto k hk).eventually_lt_const
(div_pos lowerCenterBound_pos (by norm_num) : (0 : ℝ) < lowerCenterBound / 2)
have hw := (fluctuationWindow_tendsto k hk).eventually (Filter.eventually_ge_atTop (capMultiplier k : ℝ))
filter_upwards [hsize, hrep, he, hs, heSum, heNeighbor, center_bounds_eventually k hk, hd, hw]
with n hn hr he hs hes hen hc hd hw
exact ⟨hn, hr, he.le, hs.le, hes, hen, hc.1, by linarith, hw⟩
theorem center_comparisons (k : ℕ) (hk : 3 ≤ k) :
∃ N : ℕ,
(∀ r ≥ N, ∀ s ≥ N,
min (center r k) (center s k) - 4 * densityWindow (min r s) k ≤ center (r + s) k) ∧
(∀ s ≥ N, center s k - 4 * densityWindow s k ≤ center (s + 1) k) := by
obtain ⟨N, hN⟩ := Filter.eventually_atTop.mp (centerRegular_eventually k hk)
refine ⟨N, ?_, ?_⟩
· intro r hr s hs
have hR := hN r hr
have hS := hN s hs
have hU := hN (min r s) (le_min hr hs)
have hT := hN (r + s) (by omega)
exact center_sum_comparison_of_bounds hk hR.size hS.size hR.repetition hS.repetition
hR.error hS.error hR.sampling hS.sampling hT.sumError
(hU.densitySmall.trans (le_min hR.centerLower hS.centerLower))
· intro s hs
have hS := hN s hs
have hT := hN (s + 1) (by omega)
exact center_neighbor_comparison_of_bounds hk hS.size hS.repetition hS.error hT.neighborError
(hS.densitySmall.trans hS.centerLower) hS.windowLarge
end
end FixedClauseThreshold
end OAI