OAI/Combinatorics/SharpThreshold/FourierRestrictionMass.lean
3 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.Problem313.BiasedFourier.restricted_mass_averageline 17Source documentation
Exact averaging of any selected family of conditional Fourier levels.
theorem restricted_mass_average {p : ℝ} (hp : 0 < p) (hp1 : p < 1) (f : (ι ⊕ κ → Bool) → ℝ) (L : Finset (Finset ι)) : (∑ y : κ → Bool, weight p y * ∑ A ∈ L, (coeff p (fun x => f (Sum.elim x y)) A) ^ 2) = ∑ A ∈ L, ∑ D : Finset κ, (coeff p f (A.disjSum D)) ^ 2 := by …Mentions: OAI.Problem313.BiasedFourier.weight, OAI.Problem313.BiasedFourier.coeff
- theorem
OAI.Problem313.BiasedFourier.restricted_mass_conditionline 31Source documentation
The restriction identity reindexed by full supports. The condition is placed only on the free-coordinate part, never on exterior Fourier degree.
theorem restricted_mass_condition {p : ℝ} (hp : 0 < p) (hp1 : p < 1) (f : (ι ⊕ κ → Bool) → ℝ) (P : Finset ι → Prop) [DecidablePred P] : (∑ y : κ → Bool, weight p y * ∑ A : Finset ι, if P A then (coeff p (fun x => f (Sum.elim x y)) A) ^ 2 else 0) = ∑ S : Finset (ι ⊕ κ), if P S.toLeft then (coeff p f S) ^ 2 else 0 := by …Mentions: OAI.Problem313.BiasedFourier.weight, OAI.Problem313.BiasedFourier.coeff
- theorem
OAI.Problem313.BiasedFourier.restricted_low_degree_mass_averageline 46Source documentation
Literal real-valued conditional degree cutoff, including the case
k < 1.theorem restricted_low_degree_mass_average {p : ℝ} (hp : 0 < p) (hp1 : p < 1) (f : (ι ⊕ κ → Bool) → ℝ) (k : ℝ) : (∑ y : κ → Bool, weight p y * ∑ A : Finset ι, if 1 ≤ A.card ∧ (A.card : ℝ) ≤ k then (coeff p (fun x => f (Sum.elim x y)) A) ^ 2 else 0) = ∑ S : Finset (ι ⊕ κ), if 1 ≤ S.toLeft.card ∧ (S.toLeft.card : ℝ) ≤ k then (coeff p f S) ^ 2 else 0 := by …Mentions: OAI.Problem313.BiasedFourier.weight, OAI.Problem313.BiasedFourier.coeff