OAI/InformationTheory/AmplitudeDamping/SpectralEntropy.lean

GitHub source file

10 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.GAD.trace_unitary_conj line 22

    Source documentation

    Trace invariance under a unitary change of basis.

    theorem trace_unitary_conj (U : Matrix.unitaryGroup ι ℂ) (A : Matrix ι ι ℂ) :
        (Unitary.conjStarAlgAut ℂ _ U A).trace = A.trace := by
    …
  2. theorem OAI.GAD.trace_cfc_eq line 28

    Source documentation

    Spectral trace for any function on the finite real spectrum.

    theorem trace_cfc_eq {A : Matrix ι ι ℂ} (hA : A.IsHermitian) (f : ℝ → ℝ) :
        (cfc f A).trace = ∑ i, (f (hA.eigenvalues i) : ℂ) := by
    …
  3. theorem OAI.GAD.entropy_eq_sum line 33
  4. theorem OAI.GAD.entropy_nonneg line 37
  5. theorem OAI.GAD.unitary_row_sq_sum line 49

    Source documentation

    The square-moduli in each row of a unitary matrix sum to one.

    theorem unitary_row_sq_sum (U : Matrix.unitaryGroup ι ℂ) (i : ι) :
        ∑ j, Complex.normSq (U i j) = 1 := by
    …
  6. theorem OAI.GAD.unitary_col_sq_sum line 56

    Source documentation

    The square-moduli in each column of a unitary matrix sum to one.

    theorem unitary_col_sq_sum (U : Matrix.unitaryGroup ι ℂ) (j : ι) :
        ∑ i, Complex.normSq (U i j) = 1 := by
    …
  7. theorem OAI.GAD.diag_eq_spectral_mix line 63

    Source documentation

    The ordinary diagonal is a doubly stochastic mixing of the spectral diagonal.

    theorem diag_eq_spectral_mix {A : Matrix ι ι ℂ} (hA : A.IsHermitian) (i : ι) :
        (A i i).re = ∑ j, Complex.normSq (hA.eigenvectorUnitary i j) * hA.eigenvalues j := by
    …
  8. theorem OAI.GAD.entropy_le_diagonal line 75

    Source documentation

    Pinching in any fixed orthonormal coordinate basis increases entropy.

    theorem entropy_le_diagonal {A : Matrix ι ι ℂ} (hA : A.PosSemidef) :
        entropy A ≤ ∑ i, Real.negMulLog (A i i).re := by
    …

    Mentions: OAI.GAD.entropy

  9. theorem OAI.GAD.entropy_unitary_conj line 95

    Source documentation

    Entropy is invariant under every unitary basis change.

    theorem entropy_unitary_conj (U : Matrix.unitaryGroup ι ℂ)
        {A : Matrix ι ι ℂ} (hA : A.IsHermitian) :
        entropy (Unitary.conjStarAlgAut ℂ _ U A) = entropy A := by
    …

    Mentions: OAI.GAD.entropy

  10. theorem OAI.GAD.concaveOn_entropy line 114

    Source documentation

    The full matrix entropy, not just normalized-state entropy, is concave on positive semidefinite matrices.

    theorem concaveOn_entropy :
        ConcaveOn ℝ {A : Matrix ι ι ℂ | A.PosSemidef} entropy := by
    …

    Mentions: OAI.GAD.entropy