Quantitative inequalities for the complete Sobolev lifespan #
The chosen lifespan makes the Abel contribution fit the fixed-point ball and gives a strict contraction factor.
theorem
CKN.Leray.regularisedBesselLocalLifespan_ball_bound
(ρ : RegMollifierProfile)
(ε : ℝ)
(hε : 0 < ε)
(k : ℕ)
(b : BesselPotentialSpace Foundation.Parabolic.L2Vec3 ComplexVec3 (↑(2 * k)) 2)
:
‖b‖ + 2 * (regularisedBesselTensorConstant ρ ε hε k / √(2 * Real.exp 1)) * regularisedBesselLocalRadius k b ^ 2 * √(regularisedBesselLocalLifespan ρ ε hε k b) ≤ regularisedBesselLocalRadius k b
The Abel bound of the local map fits inside the chosen H²ᵏ ball.
theorem
CKN.Leray.regularisedBesselLocalLifespan_contraction_bound
(ρ : RegMollifierProfile)
(ε : ℝ)
(hε : 0 < ε)
(k : ℕ)
(b : BesselPotentialSpace Foundation.Parabolic.L2Vec3 ComplexVec3 (↑(2 * k)) 2)
:
2 * (regularisedBesselTensorConstant ρ ε hε k / √(2 * Real.exp 1)) * (2 * regularisedBesselLocalRadius k b) * √(regularisedBesselLocalLifespan ρ ε hε k b) ≤ 1 / 2
The Abel difference bound gives contraction factor at most one half.