Samplinglib
Lean gate not recorded for this source state main · 9bb7a7394ab0

Actual numerical phase: synchronous increment in the source metric

Fan Chen, Sinho Chewi, Jianfeng Lu and Matthew S. Zhang; actual synchronous increment at exposed normalized-curvature interface, explicit universal constants, not full paper.

arXiv:2609.06906v1 · Lemma4.8, (4.16), HTML621-628; actual Lemma4.6 numerical expansion · faithful paraphrase

Complete source statement (Samplinglib restatement)

For the actual full exact-gradient two-refresh two-Picard Phi, the synchronous increment difference obeys sqrt Q_kappa((Phi_z-Phi_zprime)-(z-zprime)) <=12 h sqrt Q_kappa(z-zprime), under the explicit normalized C2 curvature interface and actual h Lambda<=1/(65536 kappa). This is the source difference of increments because vector subtraction is additive. The source universal C is explicitly elaborated as12, with the same c1/65536 as the actual contraction. All compared states and common noise values are included.

  • E is a complete finite-dimensional real inner-product Borel space, including dimension zero. f:E->R is globally C2, kappa>=1, and its genuine nested second derivative satisfies (2kappa)^-1||v||^2<=D2f(z)[v,v]<=||v||^2 for every z,v. This is the explicit normalized smoothed-potential interface; the actual f=V_eta producer remains independently open.
  • J>=2,h>0. Actual Chebyshev-Lobatto nodes t_j=h/2(1-cos(j*pi/(J-1))), cardinal polynomials ell_j and ordinary Lebesgue integral weights omega_ij=integral_0^t_i(t_i-s)ell_j(s)ds, b_j=integral_0^h ell_j(s)ds,c_j=integral_0^h(h-s)ell_j(s)ds. Lambda=sup_[0,h] sum_j|ell_j| and h Lambda<=1/(65536 kappa). No supplied convenient weights, Hessian, phase or remainder certificate.
  • a=exp(-h/2),sigma=sqrt(1-exp(-h)); P0=a p+sigma zeta0; Y0_j=x+t_j P0; Y1_i=Y0_i-sum_j omega_ij gradient f(Y0_j); Phi=(x+hP0-sum_j c_j gradient f(Y1_j),a(P0-sum_j b_j gradient f(Y1_j))+sigma zeta1). The same two noise vectors are shared by the two inputs. The inequality is for every z,zprime,zeta, not only almost surely.
  • Q_kappa(x,p)=((2kappa)^-1+1/2)||x||^2+inner(x,p)+||p||^2. The source M_kappa norm is sqrt Q. Intermediate Euclidean phase norms are the true WithLp2 product; the ordinary product max norm is not substituted.

Actual increment, explicit universal constants

\[\|\{\Phi_z(\zeta)-z\}-\{\Phi_{z\prime}(\zeta)-z\prime\}\|_{M_\kappa}\le12h\|z-z\prime\|_{M_\kappa},\qquad h\Lambda_J\le\frac1{65536\kappa}.\]

Read the formalized proofs

Each statement and proof below has its own closed Lean disclosure. Samplinglib parents, Mathlib calls and external mathematical sources are distinguished in each proof.

Samplinglib mathematical lesson

Actual numerical phase: synchronous increment in the source metric

AutoSamplingTheory.ExampleCases.SmoothedPicardHMC.ActualIncrement.source_synchronous_increment · theorem · Teaching coverage

Read this first

Mathematical statement

For the actual full exact-gradient two-refresh two-Picard Phi, the synchronous increment difference obeys sqrt Q_kappa((Phi_z-Phi_zprime)-(z-zprime)) ≤12 h sqrt Q_kappa(z-zprime), under the explicit normalized C2 curvature interface and actual h Lambda≤1/(65536 kappa). This is the source difference of increments because vector subtraction is additive. The source universal C is explicitly elaborated as12, with the same c1/65536 as the actual contraction. All compared states and common noise values are included.

\[\|\{\Phi_z(\zeta)-z\}-\{\Phi_{z\prime}(\zeta)-z\prime\}\|_{M_\kappa}\le12h\|z-z\prime\|_{M_\kappa},\qquad h\Lambda_J\le\frac1{65536\kappa}.\]
Lean statement · source_synchronous_increment

Actual integral coefficients, genuine global normalized C2 f, full Phi and all-input/common-noise difference of increments; exact original source Q.

Braces mark parameters Lean can infer; square brackets request structures such as a measurable space or probability measure. Named hypotheses are mathematical premises, not facts established by this declaration. Section parameters are described in the mathematical hypotheses above; the module link retains their exact source context.

theorem source_synchronous_increment {f : E → ℝ} {κ h : ℝ} {J : ℕ}
    (hκ : 1 ≤ κ) (hf : ContDiff ℝ 2 f)
    (hH : ∀ z v, (1 / (2 * κ)) * ‖v‖ ^ 2 ≤ (fderiv ℝ (fderiv ℝ f) z v) v ∧
      (fderiv ℝ (fderiv ℝ f) z v) v ≤ ‖v‖ ^ 2)
    (hJ : 2 ≤ J) (hh : 0 < h) :
    let t := fun i : Fin J => h/2*(1-Real.cos ((i : ℝ)/(J-1 : ℝ)*Real.pi))
    let ell := fun j : Fin J => Lagrange.basis Finset.univ t j
    let Λ := sSup ((fun s : ℝ => ∑ j : Fin J, |(ell j).eval s|) '' Icc 0 h)
    let ω := fun i j : Fin J => ∫ s in 0..t i, (t i-s)*(ell j).eval s
    let b := fun j : Fin J => ∫ s in 0..h, (ell j).eval s
    let c := fun j : Fin J => ∫ s in 0..h, (h-s)*(ell j).eval s
    h * Λ ≤ 1/(65536*κ) →
    let a := Real.exp (-h / 2)
    let sigma := Real.sqrt (1 - Real.exp (-h))
    let P0 := fun (z ζ : E × E) => a • z.2 + sigma • ζ.1
    let Y0 := fun (z ζ : E × E) j => z.1 + t j • P0 z ζ
    let Y1 := fun (z ζ : E × E) i => Y0 z ζ i - ∑ j, ω i j • gradient f (Y0 z ζ j)
    let Φ := fun w : (E × E) × (E × E) =>
      (w.1.1 + h • P0 w.1 w.2 - ∑ j, c j • gradient f (Y1 w.1 w.2 j),
        a • (P0 w.1 w.2 - ∑ j, b j • gradient f (Y1 w.1 w.2 j)) + sigma • w.2.2)
    ∀ z z' ζ : E × E,
      Real.sqrt (phaseQuadraticForm κ (((Φ (z,ζ)).1-(Φ (z',ζ)).1)-(z.1-z'.1),
        ((Φ (z,ζ)).2-(Φ (z',ζ)).2)-(z.2-z'.2))) ≤
      12*h*Real.sqrt (phaseQuadraticForm κ (z.1-z'.1,z.2-z'.2))

Exact module and namespace context

Proof roadmap

  1. 1Consume the actual numerical expansion

    The compiled actual source coefficient constructor gives Lambda≥1. Derive h≤1 and h²Lambda≤1 from the stated source step condition. Then apply the actual FirstOrderDifference constructor to this same Phi, exact source coefficients and genuine gradient. For each compared input/noise, it produces a symmetric actual segment-averaged H, ||H||op≤1, and an internally constructed R, with q=d+h A_H d+Rd and ||R||op≤8Lambda h². No H or R is a public hypothesis.

  2. 2Control the genuine drift and remainder

    From kappa≥1 and hLambda≤1/(65536kappa), derive 8hLambda≤1. The actual remainder therefore satisfies ||Rd||2≤h||d||2. The operator norm bound gives ||Hd_x||≤||d_x||. Decompose the true Euclidean product into its two coordinate axes and use the triangle inequality to obtain ||A_Hd||2≤||d_x||+2||d_p||≤3||d||2. These calculations remain inline inside this real consumer; no copied background theorem receives separate credit.

  3. 3Bound the actual synchronous increment

    Subtract d from the actual expansion. The norm of h A_Hd+Rd is at most h times3||d||2 plus h||d||2. Common noise cancellation is already established in the actual expansion parent; it is not assumed for an abstract phase.

  4. 4Reuse the exact original source metric comparisons

    Call the existing unchanged public source APIs. They prove ||v||2²≤6Q(v) and Q(v)≤3||v||2²/2. Hence Q(q-d)≤24h²||d||2²≤144h²Q(d). Both comparisons use the original exact Q, not a replacement metric or supplied coercivity certificate.

  5. 5Take square roots without dividing by displacement

    The lower comparison proves Q(d)≥0 and Q(q-d)≥0 even when d=0 or the space has dimension zero. Using squared square-root identities and nonnegative h, take square roots of the previous inequality. This yields12h sqrt Q(d); no strictly positive displacement is needed. Reordering coordinate subtraction identifies q-d with the source difference of increments.

Full assumptions and notation

All objects and hypotheses

  • E is a complete finite-dimensional real inner-product Borel space, including dimension zero. f:E→R is globally C2, kappa≥1, and its genuine nested second derivative satisfies (2kappa)^-1||v||^2≤D2f(z)[v,v]≤||v||^2 for every z,v. This is the explicit normalized smoothed-potential interface; the actual f=V_eta producer remains independently open.
  • J≥2,h>0. Actual Chebyshev-Lobatto nodes t_j=h/2(1-cos(j*pi/(J-1))), cardinal polynomials ell_j and ordinary Lebesgue integral weights omega_ij=integral_0^t_i(t_i-s)ell_j(s)ds, b_j=integral_0^h ell_j(s)ds,c_j=integral_0^h(h-s)ell_j(s)ds. Lambda=sup_[0,h] sum_j|ell_j| and h Lambda≤1/(65536 kappa). No supplied convenient weights, Hessian, phase or remainder certificate.
  • a=exp(-h/2),sigma=sqrt(1-exp(-h)); P0=a p+sigma zeta0; Y0_j=x+t_j P0; Y1_i=Y0_i-sum_j omega_ij gradient f(Y0_j); Phi=(x+hP0-sum_j c_j gradient f(Y1_j),a(P0-sum_j b_j gradient f(Y1_j))+sigma zeta1). The same two noise vectors are shared by the two inputs. The inequality is for every z,zprime,zeta, not only almost surely.
  • Q_kappa(x,p)=((2kappa)^-1+1/2)||x||^2+inner(x,p)+||p||^2. The source M_kappa norm is sqrt Q. Intermediate Euclidean phase norms are the true WithLp2 product; the ordinary product max norm is not substituted.

Mathematical proof

1. Consume the actual numerical expansion

The compiled actual source coefficient constructor gives Lambda≥1. Derive h≤1 and h²Lambda≤1 from the stated source step condition. Then apply the actual FirstOrderDifference constructor to this same Phi, exact source coefficients and genuine gradient. For each compared input/noise, it produces a symmetric actual segment-averaged H, ||H||op≤1, and an internally constructed R, with q=d+h A_H d+Rd and ||R||op≤8Lambda h². No H or R is a public hypothesis.

\[q=d+hA_Hd+Rd,\quad A_Hd=(d_p,-Hd_x-d_p),\quad\|R\|_{\rm op}\le8\Lambda_Jh^2.\]
Corresponding Lean step

hcoeff; hLambda; hs; hfirst; hp; heq; hR

2. Control the genuine drift and remainder

From kappa≥1 and hLambda≤1/(65536kappa), derive 8hLambda≤1. The actual remainder therefore satisfies ||Rd||2≤h||d||2. The operator norm bound gives ||Hd_x||≤||d_x||. Decompose the true Euclidean product into its two coordinate axes and use the triangle inequality to obtain ||A_Hd||2≤||d_x||+2||d_p||≤3||d||2. These calculations remain inline inside this real consumer; no copied background theorem receives separate credit.

\[\|Rd\|_2\le h\|d\|_2,\qquad\|A_Hd\|_2\le3\|d\|_2.\]
Corresponding Lean step

hsmall; hrprime; hHx; hAp; hA; WithLp.norm_toLp_fst; WithLp.norm_toLp_snd

3. Bound the actual synchronous increment

Subtract d from the actual expansion. The norm of h A_Hd+Rd is at most h times3||d||2 plus h||d||2. Common noise cancellation is already established in the actual expansion parent; it is not assumed for an abstract phase.

\[\|q-d\|_2=\|hA_Hd+Rd\|_2\le4h\|d\|_2.\]
Corresponding Lean step

hincr; hn; norm_add_le; norm_smul

4. Reuse the exact original source metric comparisons

Call the existing unchanged public source APIs. They prove ||v||2²≤6Q(v) and Q(v)≤3||v||2²/2. Hence Q(q-d)≤24h²||d||2²≤144h²Q(d). Both comparisons use the original exact Q, not a replacement metric or supplied coercivity certificate.

\[Q_\kappa(q-d)\le\frac32\|q-d\|_2^2\le24h^2\|d\|_2^2\le144h^2Q_\kappa(d).\]
Corresponding Lean step

ordinary_energy_le_phaseQuadraticForm; phaseQuadraticForm_le_ordinary_energy; hl; hu; hquad

5. Take square roots without dividing by displacement

The lower comparison proves Q(d)≥0 and Q(q-d)≥0 even when d=0 or the space has dimension zero. Using squared square-root identities and nonnegative h, take square roots of the previous inequality. This yields12h sqrt Q(d); no strictly positive displacement is needed. Reordering coordinate subtraction identifies q-d with the source difference of increments.

\[\sqrt{Q_\kappa(q-d)}\le12h\sqrt{Q_\kappa(d)}.\]
Corresponding Lean step

hQd0; hQi0; hsq; Real.sq_sqrt; sq_le_sq₀

Lean verification

The exact proof begins folded immediately after the mathematical argument; the statement is folded beside the claim above.

Lean proof · source_synchronous_increment

Actual expansion producer, derived R/drift/increment norms, original unchanged source Q comparisons and nonnegative square-root argument.

Braces mark parameters Lean can infer; square brackets request structures such as a measurable space or probability measure. Named hypotheses are mathematical premises, not facts established by this declaration. Section parameters are described in the mathematical hypotheses above; the module link retains their exact source context.

Download module (.lean)
theorem source_synchronous_increment {f : E → ℝ} {κ h : ℝ} {J : ℕ}
    (hκ : 1 ≤ κ) (hf : ContDiff ℝ 2 f)
    (hH : ∀ z v, (1 / (2 * κ)) * ‖v‖ ^ 2 ≤ (fderiv ℝ (fderiv ℝ f) z v) v ∧
      (fderiv ℝ (fderiv ℝ f) z v) v ≤ ‖v‖ ^ 2)
    (hJ : 2 ≤ J) (hh : 0 < h) :
    let t := fun i : Fin J => h/2*(1-Real.cos ((i : ℝ)/(J-1 : ℝ)*Real.pi))
    let ell := fun j : Fin J => Lagrange.basis Finset.univ t j
    let Λ := sSup ((fun s : ℝ => ∑ j : Fin J, |(ell j).eval s|) '' Icc 0 h)
    let ω := fun i j : Fin J => ∫ s in 0..t i, (t i-s)*(ell j).eval s
    let b := fun j : Fin J => ∫ s in 0..h, (ell j).eval s
    let c := fun j : Fin J => ∫ s in 0..h, (h-s)*(ell j).eval s
    h * Λ ≤ 1/(65536*κ) →
    let a := Real.exp (-h / 2)
    let sigma := Real.sqrt (1 - Real.exp (-h))
    let P0 := fun (z ζ : E × E) => a • z.2 + sigma • ζ.1
    let Y0 := fun (z ζ : E × E) j => z.1 + t j • P0 z ζ
    let Y1 := fun (z ζ : E × E) i => Y0 z ζ i - ∑ j, ω i j • gradient f (Y0 z ζ j)
    let Φ := fun w : (E × E) × (E × E) =>
      (w.1.1 + h • P0 w.1 w.2 - ∑ j, c j • gradient f (Y1 w.1 w.2 j),
        a • (P0 w.1 w.2 - ∑ j, b j • gradient f (Y1 w.1 w.2 j)) + sigma • w.2.2)
    ∀ z z' ζ : E × E,
      Real.sqrt (phaseQuadraticForm κ (((Φ (z,ζ)).1-(Φ (z',ζ)).1)-(z.1-z'.1),
        ((Φ (z,ζ)).2-(Φ (z',ζ)).2)-(z.2-z'.2))) ≤
      12*h*Real.sqrt (phaseQuadraticForm κ (z.1-z'.1,z.2-z'.2)) := by
  classical
  dsimp only
  let t := fun i : Fin J => h/2*(1-Real.cos ((i : ℝ)/(J-1 : ℝ)*Real.pi))
  let ell := fun j : Fin J => Lagrange.basis Finset.univ t j
  let Λ := sSup ((fun s : ℝ => ∑ j : Fin J, |(ell j).eval s|) '' Icc 0 h)
  let ω := fun i j : Fin J => ∫ s in 0..t i, (t i-s)*(ell j).eval s
  let b := fun j : Fin J => ∫ s in 0..h, (ell j).eval s
  let c := fun j : Fin J => ∫ s in 0..h, (h-s)*(ell j).eval s
  intro hstep
  change h*Λ ≤ 1/(65536*κ) at hstep
  have hcoeff := TechnicalLemmas.Analysis.ChebyshevLobattoQuadrature.chebyshev_lobatto_coefficients hJ hh
  rcases hcoeff with ⟨_,_,_,_,_,hΛ,_,_⟩
  change 1 ≤ Λ at hΛ
  have hk : 0 < κ := lt_of_lt_of_le zero_lt_one hκ
  have hi : 1/(65536*κ) ≤ (1:ℝ) := (div_le_one (by positivity)).mpr (by linarith)
  have hh1 : h ≤ 1 := by nlinarith
  have hs : h^2*Λ ≤ 1 := by
    have hm := mul_le_mul_of_nonneg_left (hstep.trans hi) (le_of_lt hh)
    nlinarith
  let a := Real.exp (-h / 2)
  let sigma := Real.sqrt (1 - Real.exp (-h))
  let P0 := fun (z ζ : E × E) => a • z.2 + sigma • ζ.1
  let Y0 := fun (z ζ : E × E) j => z.1 + t j • P0 z ζ
  let Y1 := fun (z ζ : E × E) i => Y0 z ζ i - ∑ j, ω i j • gradient f (Y0 z ζ j)
  let Φ := fun w : (E × E) × (E × E) =>
    (w.1.1 + h • P0 w.1 w.2 - ∑ j, c j • gradient f (Y1 w.1 w.2 j),
      a • (P0 w.1 w.2 - ∑ j, b j • gradient f (Y1 w.1 w.2 j)) + sigma • w.2.2)
  have hfirst := FirstOrderDifference.source_first_order_difference hκ hf hH hJ hh hs
  intro z z' ζ
  let H := h⁻¹ • ∑ j, b j •
    (∫ u in (0:ℝ)..1, InnerProductSpace.continuousLinearMapOfBilin
      (fderiv ℝ (fderiv ℝ f) (Y1 z' ζ j+u • (Y1 z ζ j-Y1 z' ζ j))))
  let d := WithLp.toLp 2 (z.1-z'.1,z.2-z'.2)
  let q := WithLp.toLp 2 ((Φ (z,ζ)).1-(Φ (z',ζ)).1,(Φ (z,ζ)).2-(Φ (z',ζ)).2)
  have hp := hfirst.2.2 z z' ζ
  change H.toLinearMap.IsSymmetric ∧ (∀ v, 1/(2*κ)*‖v‖^2 ≤ inner ℝ (H v) v ∧
    inner ℝ (H v) v ≤ ‖v‖^2) ∧ ‖H‖ ≤ 1 ∧
    ∃ R : WithLp 2 (E × E) →L[ℝ] WithLp 2 (E × E), ‖R‖ ≤ 8*Λ*h^2 ∧
      q = d+h • WithLp.toLp 2 (d.snd,-H d.fst-d.snd)+R d at hp
  rcases hp with ⟨hsym,hcurv,hHnorm,R,hR,heq⟩
  have hr : ‖R d‖ ≤ 8*Λ*h^2*‖d‖ :=
    (R.le_opNorm d).trans (mul_le_mul_of_nonneg_right hR (norm_nonneg d))
  have hsmall : 8*h*Λ ≤ 1 := by
    have hc : 8/(65536*κ) ≤ (1:ℝ) := (div_le_one (by positivity)).mpr (by linarith)
    have hm := mul_le_mul_of_nonneg_left hstep (by norm_num : (0:ℝ) ≤ 8)
    calc
      8*h*Λ = 8*(h*Λ) := by ring
      _ ≤ 8*(1/(65536*κ)) := hm
      _ = 8/(65536*κ) := by ring
      _ ≤ 1 := hc
  have hr' : ‖R d‖ ≤ h*‖d‖ := by
    have hc : 8*Λ*h^2 ≤ h := by
      have hm := mul_le_mul_of_nonneg_right hsmall (le_of_lt hh)
      nlinarith
    exact hr.trans (mul_le_mul_of_nonneg_right hc (norm_nonneg d))
  let A := WithLp.toLp 2 (d.snd,-H d.fst-d.snd)
  have hHx : ‖H d.fst‖ ≤ ‖d.fst‖ :=
    (H.le_opNorm _).trans (by simpa using mul_le_mul_of_nonneg_right hHnorm (norm_nonneg d.fst))
  have hAp : ‖-H d.fst-d.snd‖ ≤ ‖d.fst‖+‖d.snd‖ :=
    (norm_sub_le _ _).trans (by simpa using add_le_add_right hHx ‖d.snd‖)
  have hA : ‖A‖ ≤ 3*‖d‖ := by
    have ht := norm_add_le (WithLp.toLp 2 (d.snd,(0:E)))
      (WithLp.toLp 2 ((0:E),-H d.fst-d.snd))
    have hpairs : ‖A‖ ≤ ‖d.snd‖+‖-H d.fst-d.snd‖ := by
      simpa only [A, ← WithLp.toLp_add, Prod.mk_add_mk, add_zero, zero_add,
        WithLp.norm_toLp_fst, WithLp.norm_toLp_snd] using ht
    linarith [WithLp.norm_fst_le (p := 2) E d, WithLp.norm_snd_le (p := 2) E d]
  have hincr : q-d = h • A+R d := by rw [heq]; dsimp only [A]; abel
  have hn : ‖q-d‖ ≤ 4*h*‖d‖ := by
    rw [hincr]
    have ht := norm_add_le (h • A) (R d)
    rw [norm_smul, Real.norm_eq_abs, abs_of_pos hh] at ht
    nlinarith [mul_le_mul_of_nonneg_left hA (le_of_lt hh)]
  let Qd := phaseQuadraticForm κ (WithLp.ofLp d)
  let Qi := phaseQuadraticForm κ (WithLp.ofLp (q-d))
  change Real.sqrt Qi ≤ 12*h*Real.sqrt Qd
  have hl := ordinary_energy_le_phaseQuadraticForm hκ (WithLp.ofLp d)
  change ‖d.fst‖^2+‖d.snd‖^2 ≤ 6*Qd at hl
  rw [← WithLp.prod_norm_sq_eq_of_L2 d] at hl
  have hu := phaseQuadraticForm_le_ordinary_energy hκ (WithLp.ofLp (q-d))
  change Qi ≤ (3/2:ℝ)*(‖(q-d).fst‖^2+‖(q-d).snd‖^2) at hu
  rw [← WithLp.prod_norm_sq_eq_of_L2 (q-d)] at hu
  have hQd0 : 0 ≤ Qd := by nlinarith [sq_nonneg ‖d‖]
  have hQi0 : 0 ≤ Qi := by
    have hlo := ordinary_energy_le_phaseQuadraticForm hκ (WithLp.ofLp (q-d))
    change _ ≤ 6*Qi at hlo
    nlinarith [sq_nonneg ‖(q-d).fst‖,sq_nonneg ‖(q-d).snd‖]
  have hnsq : ‖q-d‖^2 ≤ (4*h*‖d‖)^2 :=
    (sq_le_sq₀ (norm_nonneg _) (by positivity)).mpr hn
  have hquad : Qi ≤ 144*h^2*Qd := by
    have hm := mul_le_mul_of_nonneg_left hl (by positivity : 0 ≤ 24*h^2)
    nlinarith
  have hsq : (Real.sqrt Qi)^2 ≤ (12*h*Real.sqrt Qd)^2 := by
    simpa only [mul_pow,Real.sq_sqrt hQd0,Real.sq_sqrt hQi0,
      show (12:ℝ)^2=144 by norm_num] using hquad
  exact (sq_le_sq₀ (Real.sqrt_nonneg _) (by positivity)).mp hsq

end
end AutoSamplingTheory.ExampleCases.SmoothedPicardHMC.ActualIncrement

Exact module and namespace context

Source assumptions versus formal assumptions

SourceActual LeanDifference kindWhy it matters
Euclidean finite real phase space and the displayed source M_kappa form.E is a complete finite-dimensional real inner-product Borel space, including dimension zero. Q_kappa(x,p)=((2kappa)^-1+1/2)||x||^2+inner(x,p)+||p||^2. The source M_kappa norm is sqrt Q. Intermediate Euclidean phase norms are the true WithLp2 product; the ordinary product max norm is not substituted.sameFinite real inner-product coordinates preserve Euclidean semantics and source Q. Borel/complete structure is explicit; zero dimension is included.
Exact gradient of the actual V_eta and its inherited normalized curvature.E is a complete finite-dimensional real inner-product Borel space, including dimension zero. f:E->R is globally C2, kappa>=1, and its genuine nested second derivative satisfies (2kappa)^-1||v||^2<=D2f(z)[v,v]<=||v||^2 for every z,v. This is the explicit normalized smoothed-potential interface; the actual f=V_eta producer remains independently open.unresolvedThe actual f=V_eta smoothing/C2/curvature producer remains independent; this exact numerical interface is proved for every genuine normalized C2 f, not a fully instantiated source lemma.
h Lambda<=c/kappa with genuine Algorithm3.1 coefficients, all common noise/input values.J>=2,h>0. Actual Chebyshev-Lobatto nodes t_j=h/2(1-cos(j*pi/(J-1))), cardinal polynomials ell_j and ordinary Lebesgue integral weights omega_ij=integral_0^t_i(t_i-s)ell_j(s)ds, b_j=integral_0^h ell_j(s)ds,c_j=integral_0^h(h-s)ell_j(s)ds. Lambda=sup_[0,h] sum_j|ell_j| and h Lambda<=1/(65536 kappa). No supplied convenient weights, Hessian, phase or remainder certificate. a=exp(-h/2),sigma=sqrt(1-exp(-h)); P0=a p+sigma zeta0; Y0_j=x+t_j P0; Y1_i=Y0_i-sum_j omega_ij gradient f(Y0_j); Phi=(x+hP0-sum_j c_j gradient f(Y1_j),a(P0-sum_j b_j gradient f(Y1_j))+sigma zeta1). The same two noise vectors are shared by the two inputs. The inequality is for every z,zprime,zeta, not only almost surely.sameThe same actual step constant1/65536 as independently VERIFIED contraction; genuine coefficients/phase produced from source expressions. No new supplied increment or H/R certificate.
Difference of increments is at most C h times initial M_kappa displacement.For the actual full exact-gradient two-refresh two-Picard Phi, the synchronous increment difference obeys sqrt Q_kappa((Phi_z-Phi_zprime)-(z-zprime)) <=12 h sqrt Q_kappa(z-zprime), under the explicit normalized C2 curvature interface and actual h Lambda<=1/(65536 kappa). This is the source difference of increments because vector subtraction is additive. The source universal C is explicitly elaborated as12, with the same c1/65536 as the actual contraction. All compared states and common noise values are included.sameCoordinate additive subtraction identifies q-d with the source expression; C is explicitly12. Derivation uses the source actual expansion and metric, including zero displacement, not an assumed Lipschitz conclusion.

Actual Lemma4.8 normalized-curvature numerical interface only. The actual f=V_eta smoothing/C2/curvature producer is a separate prerequisite before claiming the fully instantiated source lemma. No measure-level contraction, Khat/Kbar bias/variance, local discretization, invariance, history/expected query cost, Wp/proxy-warmness/initialization, PBPS or either full main/composition result is proved here. TV closeness cannot transfer unbounded expected cost.

Encoder–denoiser: accepted · equivalent-after-elaboration

A generalization is not a source correction. Proposed missing conditions require separate independent repair review. No proposed repair silently changes the original theorem.

Scope and omitted-condition boundaries
  • Actual Lemma4.8 normalized-curvature numerical interface only. The actual f=V_eta smoothing/C2/curvature producer is a separate prerequisite before claiming the fully instantiated source lemma. No measure-level contraction, Khat/Kbar bias/variance, local discretization, invariance, history/expected query cost, Wp/proxy-warmness/initialization, PBPS or either full main/composition result is proved here. TV closeness cannot transfer unbounded expected cost.
Sources, dependencies, and reuse

Source and reuse

Samplinglib parents called

Mathlib API called (external library)

  • ContinuousLinearMap.le_opNorm
  • norm_sub_le
  • norm_add_le
  • norm_smul
  • WithLp.norm_fst_le
  • WithLp.norm_snd_le
  • WithLp.norm_toLp_fst
  • WithLp.norm_toLp_snd
  • WithLp.prod_norm_sq_eq_of_L2
  • Real.sq_sqrt
  • sq_le_sq₀
  • div_le_one

Mathematical sources

  • SPHMC Lemma4.8 actual synchronous increment — Actual Lemma4.8 normalized-curvature numerical interface only. The actual f=V_eta smoothing/C2/curvature producer is a separate prerequisite before claiming the fully instantiated source lemma. No measure-level contraction, Khat/Kbar bias/variance, local discretization, invariance, history/expected query cost, Wp/proxy-warmness/initialization, PBPS or either full main/composition result is proved here. TV closeness cannot transfer unbounded expected cost.

Samplinglib prose is not a quotation or a source-equivalence certificate. Definitions and aliases are explained as constructions, not counted as new mathematical proofs.

Which proof obligations and prerequisites are covered?

  • Formalized proof edge; source adapter/review separate Actual numerical synchronous increment at exposed normalized curvature
  • TODO — not closed by these contributions Actual f=V_eta smoothing/C2/curvature producer (remaining)
  • TODO — not closed by these contributions Stochastic errors/history/cost and both full main/composition (remaining)