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theorem proved term proof

uniform_config_charge

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formal statement (Lean)

 556theorem uniform_config_charge {N : ℕ} (hN : 0 < N) (σ : ℝ) :
 557    log_charge (uniform_config hN σ) = σ := by

proof body

Term-mode proof.

 558  unfold log_charge uniform_config
 559  simp only [Real.log_exp]
 560  rw [Finset.sum_const, Finset.card_univ, Fintype.card_fin,
 561      nsmul_eq_mul, mul_div_cancel₀]
 562  exact Nat.cast_ne_zero.mpr (Nat.pos_iff_ne_zero.mp hN)
 563
 564/-- **Theorem (Explicit Solution)**:
 565    For any configuration c with log-charge σ, the uniform configuration
 566    with charge σ is the variational successor.
 567
 568    This is the explicit "equation of motion":
 569      entries(t+1) = [exp(σ/N), exp(σ/N), ..., exp(σ/N)]
 570    where σ = ∑ᵢ log(entries(t)ᵢ).
 571
 572    The uniform distribution minimizes total J-cost subject to fixed
 573    log-sum (by Jensen's inequality on the convex function J). -/

depends on (16)

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