OAI/Probability/InvariantIsing/Cavity/CavityResolventDerivative.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Differentiating the noncommuting quadratic resolvent. The resulting compression identifies the common root covariance from the same scalar Schur identity used at the positive levels.

  1. lemma OAI.InvariantIsing.hasDerivAt_cavityMatrixInverse line 15
  2. lemma OAI.InvariantIsing.cavityResolvent_identity_add line 29
  3. theorem OAI.InvariantIsing.hasDerivAt_cavityResolvent line 48

    Source documentation

    The root covariance identity cav:q-root-covariance holds without commuting the covariance path with the quadratic coefficient.

    theorem hasDerivAt_cavityResolvent {d : ℕ}
        (K : Matrix (Fin d) (Fin d) ℝ) (H : ℝ → Matrix (Fin d) (Fin d) ℝ)
        (H' : Matrix (Fin d) (Fin d) ℝ) (x : ℝ)
        (hK : K.transpose = K) (hHx : (H x).transpose = H x)
        (hH : HasDerivAt H H' x) (hdet : IsUnit (1 - H x * K).det) :
        HasDerivAt (fun t => cavityResolvent K (H t))
          ((1 - H x * K)⁻¹ * H' * ((1 - H x * K)⁻¹).transpose) x := by
    …

    Mentions: OAI.InvariantIsing.cavityResolvent

  4. theorem OAI.InvariantIsing.cavity_projected_root_covariance line 70

    Source documentation

    Differentiating the scalar Schur field identifies the projected common-root covariance. The local scalar identity is supplied by the proved finite spectral Schur evaluation.

    theorem cavity_projected_root_covariance {d n : ℕ}
        (K : Matrix (Fin d) (Fin d) ℝ) (H : ℝ → Matrix (Fin d) (Fin d) ℝ)
        (H' : Matrix (Fin d) (Fin d) ℝ) (L : Matrix (Fin d) (Fin n) ℝ)
        (C₀ : Matrix (Fin n) (Fin n) ℝ) (R : ℝ → ℝ) (R' x : ℝ)
        (hK : K.transpose = K) (hHx : (H x).transpose = H x)
        (hH : HasDerivAt H H' x) (hdet : IsUnit (1 - H x * K).det)
        (hR : HasDerivAt R R' x)
        (hscalar : (fun t => C₀ + L.transpose * cavityResolvent K (H t) * L) =ᶠ[𝓝 x]
          (fun t => R t • (1 : Matrix (Fin n) (Fin n) ℝ))) :
        L.transpose * ((1 - H x * K)⁻¹ * H' * ((1 - H x * K)⁻¹).transpose) * L =
          R' • 1 := by
    …

    Mentions: OAI.InvariantIsing.cavityResolvent