OAI/InformationTheory/AmplitudeDamping/SpectralEntropy.lean
10 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.GAD.trace_unitary_conjline 22Source 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 … - theorem
OAI.GAD.trace_cfc_eqline 28Source 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 … - theorem
OAI.GAD.entropy_eq_sumline 33 - theorem
OAI.GAD.entropy_nonnegline 37 - theorem
OAI.GAD.unitary_row_sq_sumline 49Source 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 … - theorem
OAI.GAD.unitary_col_sq_sumline 56Source 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 … - theorem
OAI.GAD.diag_eq_spectral_mixline 63Source 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 … - theorem
OAI.GAD.entropy_le_diagonalline 75Source 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
- theorem
OAI.GAD.entropy_unitary_conjline 95Source 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
- theorem
OAI.GAD.concaveOn_entropyline 114Source 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