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RoughPaths.Sewing.Scaled

Sewing with a constant-scaled control #

The additive sewing lemma packaged for germs whose defect is bounded by C·ω^θ: the scaling constant is absorbed into the control, so all three rough-integral constructions (word, branched, planarly branched) reduce to one application.

theorem RoughPaths.Sewing.sewing_const_mul {T : Type u_1} [LinearOrder T] {E : Type u_2} [NormedAddCommGroup E] [CompleteSpace E] (ω : Control T) (Ξ : TTE) {θ : } {C : ENNReal} ( : 1 < θ) (hθ0 : θ 0) (hC : C ) ( : ∀ ⦃a b c : T⦄, a bb cΞ a c - Ξ a b - Ξ b c‖ₑ C * ω.toFun a c ^ θ) (hfine : HasFinePartitions ω) ( : ∀ ⦃s t : T⦄, s tω.toFun s t ) :
∃ (I : TTE), (∀ ⦃s u t : T⦄, s uu tI s u + I u t = I s t) (∀ ⦃s t : T⦄, s tI s t - Ξ s t‖ₑ sewingConst θ * (C * ω.toFun s t ^ θ)) ∀ ⦃s t : T⦄, s t∀ (ε : ENNReal) (mid : List T), List.IsChain (fun (a b : T) => a b (Control.constMul (C ^ θ⁻¹) ω).toFun a b ε) (s :: (mid ++ [t]))I s t - pairSum Ξ (s :: (mid ++ [t]))‖ₑ sewingConst θ * (ε ^ (θ - 1) * (Control.constMul (C ^ θ⁻¹) ω).toFun s t)

Scaled sewing: a germ with defect bound C·ω^θ, θ > 1, sews into an additive primitive with the correspondingly scaled estimates.