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LeanPool.PLAcceleratedNesterovLean.Convergence.GenLocalArgument

Per-Phase Gen Convergence (State-Based Local Argument) #

State-based ("gen") version of LocalArgument.lean. For each m⋆ ∈ M, chains local_fiberwise_geometry, lyapunov_coercivity_gen, curv_absorb_assembly_gen, lyapunov_contraction_gen, motion bounds, and bootstrap_total_displacement_gen

to produce a ball around m⋆ where the Nesterov iterates starting from an arbitrary initial state s₀ (not just v=0) converge geometrically.

State-based version of LocalArgument.lean. The conclusion provides gen bootstrap output: ∃ δ > 0, ∀ s₀ near m⋆ with small Lyapunov → iterates stay in Ω ∧ Lyapunov decays geometrically with nesterovSeqGen.

theorem PLAcceleratedNesterovLean.local_convergence_at_base_point_gen {d : } (hd : 0 < d) (L : NNReal) (hL : 0 < L) (μ : ) ( : 0 < μ) (hμ_le_L : μ L) (μ_minus : ) (hμ_minus : 0 < μ_minus) (hμ_minus_lt : μ_minus < μ) (θ : ) ( : 0 < θ) (hθ_lt1 : θ < 1) (f : E d) (S : Set (E d)) (hrange : S = argminSet f) (U : Set (E d)) (hTub_sub : IsTubularNeighborhoodOfSubmanifold S U) (hPL : PolyakLojasiewicz f μ U) (hf_C2 : ContDiffOn 2 f U) (hf_lip : LipschitzOnWith L (gradient f) U) (π : E dE d) (hπ_on_U : xU, π x S dist x (π x) = Metric.infDist x S) (hπ_fix : xS, π x = x) (hπ_in_S : ∀ (x : E d), π x S) (hgrad_zero : xS, gradient f x = 0) (mstar : E d) (hmstar : mstar S) :
have η := 1 / L; have ρ := (1 - (μ_minus * η)) / (1 + (μ_minus * η)); have P := fderiv π mstar; ∃ (Ω : Set (E d)) (δ : ) (r_ball : ) (C_coer : ), IsOpen Ω mstar Ω Ω U 0 < δ 0 < r_ball 0 < C_coer Metric.ball mstar r_ball Ω (∀ (x : E d), P (P x) = P x) (∀ (v : E d), P v v) μ_minus * η < 1 (∀ (s : NesterovState d), s.x Ωs.lookahead η Ωs.v ^ 2 + μ_minus * normalDispOfState π η s ^ 2 C_coer * lyapunovOfState P μ_minus π f η s) ∀ (s₀ : NesterovState d), s₀.x Metric.ball mstar δs₀.lookahead η Metric.ball mstar δlyapunovOfState P μ_minus π f η s₀ δ ^ 2(∀ (n : ), (nesterovSeqGen f η ρ s₀ n).x Ω (nesterovSeqGen f η ρ s₀ n).lookahead η Ω) (∀ (n : ), (nesterovSeqGen f η ρ s₀ n).x Metric.ball mstar r_ball (nesterovSeqGen f η ρ s₀ n).lookahead η Metric.ball mstar r_ball) (∀ (n : ), lyapunovOfState P μ_minus π f η (nesterovSeqGen f η ρ s₀ (n + 1)) (1 - (1 - θ) * (μ_minus * η)) ^ (n + 1) * lyapunovOfState P μ_minus π f η s₀) ∀ (j : ) (t : ), 0 tt 1π ((nesterovSeqGen f η ρ s₀ j).lookahead η) + t ((nesterovSeqGen f η ρ s₀ j).lookahead η - π ((nesterovSeqGen f η ρ s₀ j).lookahead η)) U

Public theorem wrapper for localConvergenceAtBasePointGenProof.