• BenevolentOne@infosec.pub
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    12 hours ago

    You know what all those methods have in common? FUCKING evaluation of smooth continuous functions based on a limited number of samples.

    REAL MEN WRITE REAL PROOFS. They don’t use God damned computational methods which completely IGNORE non-converging regions.

    I used opus to generate this lean-verifiable proof that you in particular are full of shit!

    import Mathlib
    open Real
    
    noncomputable def f (x : ℝ) : ℝ := sin* x) * exp (-x^2)
    
    lemma f_smooth : ContDiff ℝ ⊤ f :=
      (contDiff_sin.comp (contDiff_const.mul contDiff_id)).mul
        (contDiff_exp.comp (contDiff_id.pow 2).neg)
    
    lemma f_zero_on_ints : ∀ n : ℤ, f n = 0 := by
      intro n
      show sin* (n : ℝ)) * exp (-((n : ℝ))^2) = 0
      rw [mul_comm π (n : ℝ), sin_int_mul_pi, zero_mul]
    
    lemma f_ne_zero : f ≠ 0 := fun h => by
      have h₁ : f (1/2) = 0 := congrFun h (1/2)
      have h₂ : f (1/2) = exp (-(1/2)^2) := by
        show sin* (1/2)) * exp (-(1/2)^2) = exp (-(1/2)^2)
        rw [show π * (1/2) = π/2 from by ring, sin_pi_div_two, one_mul]
      exact (exp_pos _).ne' (h₂ ▸ h₁)
    
    theorem sampling_is_a_lie :
        ∃ f : ℝ → ℝ,
          ContDiff ℝ ⊤ f ∧
          (∀ n : ℤ, f n = 0) ∧
          f ≠ 0 :=
      ⟨f, f_smooth, f_zero_on_ints, f_ne_zero⟩