OAI/Analysis/MatrixScaling/Spectrum.lean

GitHub source file

21 declarations, 0 contain sorry, 0 declared as axioms

Spectral min-max bounds, continuity, and compactness of projections.

  1. def OAI.Kaplansky.spectralForm line 17
  2. theorem OAI.Kaplansky.basis_norm_sq line 20
  3. theorem OAI.Kaplansky.basis_intersection_vector line 27

    Source documentation

    Two full bases have a nonzero vector in the first k+1 coordinates of one basis and in the last r-k coordinates of the other.

    theorem basis_intersection_vector (a b : OrthonormalBasis (Fin r) ℂ E) (k : Fin r) :
        ∃ x : E, x ≠ 0 ∧ (∀ i : Fin r, k < i → a.repr x i = 0) ∧
          (∀ i : Fin r, i < k → b.repr x i = 0) := by
    …
  4. theorem OAI.Kaplansky.spectralForm_eigenvalue_mono line 77

    Source documentation

    The min--max comparison, proved by a dimension intersection and quadratic-form bounds in two orthonormal bases.

    theorem spectralForm_eigenvalue_mono
        (a b : OrthonormalBasis (Fin r) ℂ E) (e f : Fin r → ℝ)
        (he : Antitone e) (hf : Antitone f)
        (horder : ∀ x, spectralForm a e x ≤ spectralForm b f x) (k : Fin r) : e k ≤ f k := by
    …

    Mentions: OAI.Kaplansky.spectralForm

  5. theorem OAI.Kaplansky.symmetric_spectralForm line 99
  6. theorem OAI.Kaplansky.symmetric_eigenvalues_mono line 120

    Source documentation

    Eigenvalue monotonicity for symmetric operators from quadratic-form order.

    theorem symmetric_eigenvalues_mono [FiniteDimensional ℂ E]
        {T S : E →ₗ[ℂ] E} (hT : T.IsSymmetric) (hS : S.IsSymmetric)
        (hn : Module.finrank ℂ E = r)
        (horder : ∀ x, (inner ℂ x (T x)).re ≤ (inner ℂ x (S x)).re) (k : Fin r) :
        hT.eigenvalues hn k ≤ hS.eigenvalues hn k := by
    …
  7. theorem OAI.Kaplansky.decreasingEigenvalues_mono line 130
  8. theorem OAI.Kaplansky.symmetric_eigenvalues_smul_le line 154
  9. theorem OAI.Kaplansky.decreasingEigenvalues_smul_le line 170
  10. theorem OAI.Kaplansky.quadraticForm_norm_bound line 195
  11. theorem OAI.Kaplansky.spectralForm_add_const line 204
  12. theorem OAI.Kaplansky.symmetric_eigenvalue_le_add_norm line 210
  13. theorem OAI.Kaplansky.decreasingEigenvalues_sub_le_norm line 225

    Source documentation

    Ordered eigenvalues are 1-Lipschitz in the actual operator norm.

    theorem decreasingEigenvalues_sub_le_norm {A B : Matrix (Fin r) (Fin r) ℂ}
        (hA : A.IsHermitian) (hB : B.IsHermitian) (k : Fin r) :
        |decreasingEigenvalues hA k - decreasingEigenvalues hB k| ≤ ‖A-B‖ := by
    …

    Mentions: OAI.Kaplansky.decreasingEigenvalues

  14. theorem OAI.Kaplansky.lipschitz_decreasingEigenvalues line 242
  15. theorem OAI.Kaplansky.continuous_decreasingEigenvalues line 250
  16. theorem OAI.Kaplansky.projection_eigenvalue_zero_or_one line 268
  17. theorem OAI.Kaplansky.projection_trace_eq_rank line 283
  18. abbrev OAI.Kaplansky.projectionSpace line 296

    Source documentation

    Orthogonal rank-s projections, represented by equations with continuous left-hand sides; the trace equation is equivalent to the rank condition.

    abbrev projectionSpace (d s : ℕ) :=
    …
  19. theorem OAI.Kaplansky.projectionSpace_rank line 299
  20. theorem OAI.Kaplansky.isCompact_projectionSpace line 304
  21. instance OAI.Kaplansky.(instance at line 320) line 320