OAI/Geometry/EinsteinFour/ScalarDirichlet.lean

GitHub source file

19 declarations, 0 contain sorry, 0 declared as axioms

The positive first mode of the scalar Dirichlet comparison matrix.

  1. def OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet line 14
  2. theorem OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet_isHermitian line 18
  3. theorem OAI.PositiveEinsteinFour.Jacobi.predecessor_sum line 24
  4. theorem OAI.PositiveEinsteinFour.Jacobi.successor_sum line 42
  5. theorem OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet_apply_sequence line 59
  6. theorem OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet_sine_eigenvector line 68
  7. theorem OAI.PositiveEinsteinFour.Jacobi.weighted_row_sum line 84
  8. theorem OAI.PositiveEinsteinFour.Jacobi.scalar_ground_state_identity line 104

    Source documentation

    The scalar ground-state identity. It keeps the off-diagonal entries explicit, so its sign applies directly to the tridiagonal reference.

    theorem scalar_ground_state_identity {I : Type*} [Fintype I]
        (L : Matrix I I ℝ) (w y : I → ℝ) (lam : ℝ)
        (hsymm : L.IsHermitian) (heigen : L *ᵥ w = lam • w) :
        (∑ i, ∑ j, (-L i j * w i * w j) * (y i - y j) ^ 2) =
          2 * ((fun i => w i * y i) ⬝ᵥ (L *ᵥ fun i => w i * y i) -
            lam * ∑ i, w i ^ 2 * y i ^ 2) := by
    …
  9. theorem OAI.PositiveEinsteinFour.Jacobi.scalar_posDef_of_positive_mode line 144

    Source documentation

    A positive first eigenvector with positive eigenvalue proves positivity of a symmetric scalar matrix with nonpositive off-diagonal entries.

    theorem scalar_posDef_of_positive_mode {I : Type*} [Fintype I] [DecidableEq I]
        (L : Matrix I I ℝ) (w : I → ℝ) (lam : ℝ)
        (hsymm : L.IsHermitian) (hoff : ∀ i j, i ≠ j → L i j ≤ 0)
        (hw : ∀ i, 0 < w i) (hlam : 0 < lam) (heigen : L *ᵥ w = lam • w) :
        L.PosDef := by
    …
  10. def OAI.PositiveEinsteinFour.Jacobi.firstSineAngle line 180
  11. def OAI.PositiveEinsteinFour.Jacobi.firstSineVector line 182
  12. theorem OAI.PositiveEinsteinFour.Jacobi.firstSineVector_pos line 184
  13. theorem OAI.PositiveEinsteinFour.Jacobi.firstSineVector_eigenvector line 193
  14. theorem OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet_posDef line 205

    Source documentation

    Positivity of the scalar reference follows from its first sine mode; no diagonalization of the other sine modes is needed.

    theorem scalarDirichlet_posDef (N : ℕ) (d : ℝ)
        (hfirst : 0 < d - 2 * Real.cos (firstSineAngle N)) :
        (scalarDirichlet N d).PosDef := by
    …

    Mentions: OAI.PositiveEinsteinFour.Jacobi.firstSineAngle, OAI.PositiveEinsteinFour.Jacobi.scalarDirichlet

  15. def OAI.PositiveEinsteinFour.Jacobi.firstSineNormSq line 215
  16. theorem OAI.PositiveEinsteinFour.Jacobi.firstSineNormSq_pos line 217
  17. def OAI.PositiveEinsteinFour.Jacobi.unitFirstSineVector line 221
  18. theorem OAI.PositiveEinsteinFour.Jacobi.unitFirstSineVector_norm line 224
  19. theorem OAI.PositiveEinsteinFour.Jacobi.unitFirstSineVector_eigenvector line 233