OAI/Probability/InvariantIsing/Spectral/SpectralDiagonalPerturbation.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

The deterministic spectral-diagonal perturbation as an exact eigenvalue shift.

  1. def OAI.InvariantIsing.diagonalPerturbedEigenvalues line 15
  2. theorem OAI.InvariantIsing.rotatedEnergy_diagonalPerturbation line 21

    Source documentation

    This is the first term of the manuscript's perturbation, including its coefficient N e_N, in the actual rotated Ising Hamiltonian.

    theorem rotatedEnergy_diagonalPerturbation {N m : ℕ} (hN : 0 < N)
        (eig : Fin N → ℝ) (U : Rotation N) (I : Fin m → Finset (Fin N))
        (v : Fin m → ℝ) (t : ℝ) (σ : Spin N) :
        rotatedEnergy (diagonalPerturbedEigenvalues eig I v t) U σ =
          t * rotatedEnergy eig U σ + N * perturbationScale N * ∑ a, v a * projectedOverlap U (I a) σ σ := by
    …

    Mentions: OAI.InvariantIsing.Rotation, OAI.InvariantIsing.Spin, OAI.InvariantIsing.rotatedEnergy, OAI.InvariantIsing.diagonalPerturbedEigenvalues, OAI.InvariantIsing.projectedOverlap

  3. lemma OAI.InvariantIsing.diagonalPerturbedEigenvalues_abs_le line 60
  4. lemma OAI.InvariantIsing.rotatedEnergy_diagonal_coordinate line 91

    Source documentation

    Replacing one diagonal coordinate adds exactly its bounded observable, even when all other spectral coordinates and the temperature are present.

    lemma rotatedEnergy_diagonal_coordinate {N m : ℕ} (hN : 0 < N)
        (eig : Fin N → ℝ) (U : Rotation N) (I : Fin m → Finset (Fin N))
        (v : Fin m → ℝ) (t : ℝ) (a : Fin m) (w : ℝ) (σ : Spin N) :
        rotatedEnergy (diagonalPerturbedEigenvalues eig I (Function.update v a w) t) U σ =
          rotatedEnergy (diagonalPerturbedEigenvalues eig I (Function.update v a 0) t) U σ +
            N * perturbationScale N * w * projectedOverlap U (I a) σ σ := by
    …

    Mentions: OAI.InvariantIsing.Rotation, OAI.InvariantIsing.Spin, OAI.InvariantIsing.rotatedEnergy, OAI.InvariantIsing.diagonalPerturbedEigenvalues, OAI.InvariantIsing.projectedOverlap

  5. lemma OAI.InvariantIsing.abs_rotatedEnergy_diagonalPerturbation_le line 113