OAI/Geometry/ProjectionBodies/SphericalCore.lean

GitHub source file

132 declarations, 0 contain sorry, 0 declared as axioms

  1. abbrev OAI.PettyProjection.Spherical.Space line 13
  2. abbrev OAI.PettyProjection.Spherical.Sphere line 14
  3. def OAI.PettyProjection.Spherical.surface line 16
  4. def OAI.PettyProjection.Spherical.sigma line 19
  5. instance OAI.PettyProjection.Spherical.surface_finite line 22
  6. lemma OAI.PettyProjection.Spherical.surface_ne_zero line 26
  7. instance OAI.PettyProjection.Spherical.sigma_probability line 29
  8. instance OAI.PettyProjection.Spherical.surface_open_pos line 35
  9. instance OAI.PettyProjection.Spherical.sigma_open_pos line 39
  10. def OAI.PettyProjection.Spherical.mean line 43

    Source documentation

    Spherical means in the probability normalization.

    def mean {n : ℕ} (f : Sphere n → ℝ) : ℝ := ∫ u, f u ∂sigma n

    Mentions: OAI.PettyProjection.Spherical.Sphere, OAI.PettyProjection.Spherical.sigma

  11. lemma OAI.PettyProjection.Spherical.mean_const line 45
  12. instance OAI.PettyProjection.Spherical.sphere_compact line 48
  13. lemma OAI.PettyProjection.Spherical.norm_coe line 51
  14. abbrev OAI.PettyProjection.Spherical.H line 55

    Source documentation

    Continuous functions are put into the actual spherical L² space.

    abbrev H (n : ℕ) := Lp ℝ 2 (sigma n)

    Mentions: OAI.PettyProjection.Spherical.sigma

  15. def OAI.PettyProjection.Spherical.toH line 57
  16. def OAI.PettyProjection.Spherical.coordinateProduct line 62

    Source documentation

    Restrictions of ambient coordinate quadratics. Their span contains the constants on the unit sphere and all degree-two spherical harmonics.

    def coordinateProduct (n : ℕ) (i j : Fin n) : C(Sphere n, ℝ) where
    …

    Mentions: OAI.PettyProjection.Spherical.Sphere

  17. def OAI.PettyProjection.Spherical.lowSpace line 66
  18. instance OAI.PettyProjection.Spherical.lowSpace_finite line 70
  19. def OAI.PettyProjection.Spherical.Q line 75

    Source documentation

    The complement of the constants and the quadratics. For even input this is exactly the even tail of degree at least four.

    def Q (n : ℕ) [NeZero n] : H n →L[ℝ] H n :=
    …

    Mentions: OAI.PettyProjection.Spherical.H

  20. lemma OAI.PettyProjection.Spherical.sum_coordinateProduct line 78
  21. lemma OAI.PettyProjection.Spherical.constant_mem_lowSpace line 85
  22. lemma OAI.PettyProjection.Spherical.Q_eq_sub line 97
  23. lemma OAI.PettyProjection.Spherical.Q_constant line 101
  24. lemma OAI.PettyProjection.Spherical.norm_Q_le line 106
  25. lemma OAI.PettyProjection.Spherical.inner_toH line 109
  26. lemma OAI.PettyProjection.Spherical.norm_toH_sq line 113
  27. lemma OAI.PettyProjection.Spherical.norm_Q_le_centered line 118
  28. def OAI.PettyProjection.Spherical.sphereMap line 129

    Source documentation

    Orthogonal changes of variables on the actual unit sphere.

    def sphereMap {n : ℕ} (U : Space n ≃ₗᵢ[ℝ] Space n) : Sphere n ≃ₜ Sphere n where
    …

    Mentions: OAI.PettyProjection.Spherical.Space, OAI.PettyProjection.Spherical.Sphere

  29. lemma OAI.PettyProjection.Spherical.cone_preimage line 137
  30. lemma OAI.PettyProjection.Spherical.surface_preserving line 150
  31. lemma OAI.PettyProjection.Spherical.sigma_preserving line 159
  32. lemma OAI.PettyProjection.Spherical.mean_rotation line 163
  33. def OAI.PettyProjection.Spherical.rotation line 174

    Source documentation

    Exponentiating an actual skew-adjoint operator produces rotations.

    def rotation {n : ℕ} (T : Space n →L[ℝ] Space n) (hT : star T = -T) (t : ℝ) :
        Space n ≃ₗᵢ[ℝ] Space n :=
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  34. lemma OAI.PettyProjection.Spherical.rotation_apply line 180
  35. lemma OAI.PettyProjection.Spherical.rotation_zero line 183
  36. lemma OAI.PettyProjection.Spherical.hasDerivAt_rotation line 190
  37. lemma OAI.PettyProjection.Spherical.continuous_integrable line 196
  38. lemma OAI.PettyProjection.Spherical.mean_fderiv_skew line 204

    Source documentation

    Infinitesimal rotation invariance, with differentiation justified using uniform derivative bounds on the compact sphere. This supplies spherical integration by parts without postulating it as an interface.

    lemma mean_fderiv_skew {n : ℕ} [NeZero n] (T : Space n →L[ℝ] Space n)
        (hT : star T = -T) (f : Space n → ℝ) (hf : ContDiff ℝ 1 f) :
        mean (fun u : Sphere n => fderiv ℝ f u (T u)) = 0 := by
    …

    Mentions: OAI.PettyProjection.Spherical.Space, OAI.PettyProjection.Spherical.mean, OAI.PettyProjection.Spherical.Sphere

  39. def OAI.PettyProjection.Spherical.rotDeriv line 244

    Source documentation

    Derivative along an infinitesimal linear rotation.

    def rotDeriv {n : ℕ} (T : Space n →L[ℝ] Space n) (f : Space n → ℝ) : Space n → ℝ :=
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  40. lemma OAI.PettyProjection.Spherical.continuous_rotDeriv line 247
  41. lemma OAI.PettyProjection.Spherical.contDiff_rotDeriv line 251
  42. lemma OAI.PettyProjection.Spherical.rotDeriv_mul line 255
  43. lemma OAI.PettyProjection.Spherical.mean_rotDeriv_mul line 263

    Source documentation

    Genuine spherical integration by parts for each rotation generator.

    lemma mean_rotDeriv_mul {n : ℕ} [NeZero n] (T : Space n →L[ℝ] Space n)
        (hT : star T = -T) {f g : Space n → ℝ}
        (hf : ContDiff ℝ 1 f) (hg : ContDiff ℝ 1 g) :
        mean (fun u : Sphere n => f u * rotDeriv T g u) =
          - mean (fun u : Sphere n => g u * rotDeriv T f u) := by
    …

    Mentions: OAI.PettyProjection.Spherical.Space, OAI.PettyProjection.Spherical.mean, OAI.PettyProjection.Spherical.Sphere, OAI.PettyProjection.Spherical.rotDeriv

  44. def OAI.PettyProjection.Spherical.generator line 284

    Source documentation

    The standard skew generator in the i,j plane.

    def generator (n : ℕ) (i j : Fin n) : Space n →L[ℝ] Space n :=
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  45. lemma OAI.PettyProjection.Spherical.generator_skew line 288
  46. lemma OAI.PettyProjection.Spherical.generator_apply line 293
  47. lemma OAI.PettyProjection.Spherical.generator_apply_coord line 297
  48. lemma OAI.PettyProjection.Spherical.generator_self line 302
  49. lemma OAI.PettyProjection.Spherical.generator_swap line 305
  50. def OAI.PettyProjection.Spherical.energy line 309

    Source documentation

    The Dirichlet form, expressed without local coordinates by rotations.

    def energy {n : ℕ} (f g : Space n → ℝ) : ℝ :=
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  51. def OAI.PettyProjection.Spherical.casimir line 315

    Source documentation

    The spherical Laplacian expressed by its rotation generators.

    def casimir {n : ℕ} (f : Space n → ℝ) : Space n → ℝ := fun x =>
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  52. lemma OAI.PettyProjection.Spherical.energy_symm line 319
  53. lemma OAI.PettyProjection.Spherical.energy_nonneg line 322
  54. lemma OAI.PettyProjection.Spherical.mean_sum line 330
  55. lemma OAI.PettyProjection.Spherical.mean_casimir line 335
  56. def OAI.PettyProjection.Spherical.polynomialFunction line 365

    Source documentation

    Ambient evaluation of a polynomial, using the Euclidean coordinates.

    def polynomialFunction {n : ℕ} (p : MvPolynomial (Fin n) ℝ) : Space n → ℝ :=
    …

    Mentions: OAI.PettyProjection.Spherical.Space

  57. lemma OAI.PettyProjection.Spherical.polynomialFunction_contDiff line 368
  58. def OAI.PettyProjection.Spherical.polynomialRotation line 379

    Source documentation

    Polynomial rotation differentiation, a derivation preserving degree.

    def polynomialRotation {n : ℕ} (i j : Fin n) (p : MvPolynomial (Fin n) ℝ) :
        MvPolynomial (Fin n) ℝ :=
    …
  59. lemma OAI.PettyProjection.Spherical.rotDeriv_add line 383
  60. lemma OAI.PettyProjection.Spherical.rotDeriv_const line 388
  61. lemma OAI.PettyProjection.Spherical.rotDeriv_coordinate line 392
  62. lemma OAI.PettyProjection.Spherical.polynomialRotation_add line 399
  63. lemma OAI.PettyProjection.Spherical.polynomialRotation_mul line 404
  64. lemma OAI.PettyProjection.Spherical.polynomialRotation_C line 410
  65. lemma OAI.PettyProjection.Spherical.polynomialFunction_add line 414
  66. lemma OAI.PettyProjection.Spherical.polynomialFunction_mul line 419
  67. lemma OAI.PettyProjection.Spherical.polynomialFunction_X line 424
  68. lemma OAI.PettyProjection.Spherical.polynomialFunction_C line 429
  69. lemma OAI.PettyProjection.Spherical.rotDeriv_polynomialFunction line 435

    Source documentation

    The formal polynomial generator agrees with actual differentiation.

    lemma rotDeriv_polynomialFunction {n : ℕ} (i j : Fin n) (p : MvPolynomial (Fin n) ℝ) :
        rotDeriv (generator n i j) (polynomialFunction p) =
          polynomialFunction (polynomialRotation i j p) := by
    …

    Mentions: OAI.PettyProjection.Spherical.rotDeriv, OAI.PettyProjection.Spherical.generator, OAI.PettyProjection.Spherical.polynomialFunction, OAI.PettyProjection.Spherical.polynomialRotation

  70. def OAI.PettyProjection.Spherical.radiusPolynomial line 462

    Source documentation

    Radius squared as an ambient polynomial.

    def radiusPolynomial (n : ℕ) : MvPolynomial (Fin n) ℝ := ∑ i : Fin n, X i ^ 2
  71. def OAI.PettyProjection.Spherical.eulerPolynomial line 464
  72. def OAI.PettyProjection.Spherical.laplacePolynomial line 467
  73. lemma OAI.PettyProjection.Spherical.polynomialRotation_twice line 470
  74. lemma OAI.PettyProjection.Spherical.eulerPolynomial_twice line 484
  75. lemma OAI.PettyProjection.Spherical.sum_polynomialRotation_twice line 496
  76. def OAI.PettyProjection.Spherical.eigenvalue line 532

    Source documentation

    The spherical Laplace eigenvalues.

    def eigenvalue (n d : ℕ) : ℝ := (d : ℝ) * ((d : ℝ) + n - 2)
  77. lemma OAI.PettyProjection.Spherical.eulerPolynomial_nsmul line 534
  78. lemma OAI.PettyProjection.Spherical.eulerPolynomial_homogeneous line 541
  79. lemma OAI.PettyProjection.Spherical.sum_polynomialRotation_homogeneous line 545
  80. lemma OAI.PettyProjection.Spherical.polynomialFunction_radius line 556
  81. lemma OAI.PettyProjection.Spherical.casimir_polynomialFunction line 564

    Source documentation

    Polar Laplacian identity, derived from finite rotation sums and Euler's identity rather than assumed as a spherical calculus interface.

    lemma casimir_polynomialFunction {n d : ℕ} {p : MvPolynomial (Fin n) ℝ}
        (hp : p.IsHomogeneous d) (x : Space n) :
        casimir (polynomialFunction p) x =
          ‖x‖ ^ 2 * polynomialFunction (laplacePolynomial p) x -
            eigenvalue n d * polynomialFunction p x := by
    …

    Mentions: OAI.PettyProjection.Spherical.Space, OAI.PettyProjection.Spherical.casimir, OAI.PettyProjection.Spherical.polynomialFunction, OAI.PettyProjection.Spherical.laplacePolynomial, OAI.PettyProjection.Spherical.eigenvalue

  82. lemma OAI.PettyProjection.Spherical.casimir_harmonic line 579
  83. lemma OAI.PettyProjection.Spherical.eigenvalue_strictMono line 585
  84. lemma OAI.PettyProjection.Spherical.harmonic_orthogonal line 596

    Source documentation

    Distinct homogeneous harmonic degrees are orthogonal under actual normalized surface measure.

    lemma harmonic_orthogonal {n d e : ℕ} (hn : 2 ≤ n)
        {p q : MvPolynomial (Fin n) ℝ} (hp : p.IsHomogeneous d) (hq : q.IsHomogeneous e)
        (hΔp : laplacePolynomial p = 0) (hΔq : laplacePolynomial q = 0) (hde : d ≠ e) :
        mean (fun u : Sphere n => polynomialFunction p u * polynomialFunction q u) = 0 := by
    …

    Mentions: OAI.PettyProjection.Spherical.laplacePolynomial, OAI.PettyProjection.Spherical.mean, OAI.PettyProjection.Spherical.Sphere, OAI.PettyProjection.Spherical.polynomialFunction

  85. lemma OAI.PettyProjection.Spherical.laplacePolynomial_add line 617
  86. lemma OAI.PettyProjection.Spherical.laplacePolynomial_sub line 621
  87. lemma OAI.PettyProjection.Spherical.laplacePolynomial_C_mul line 625
  88. lemma OAI.PettyProjection.Spherical.laplacePolynomial_homogeneous line 629
  89. lemma OAI.PettyProjection.Spherical.pderiv_radiusPolynomial line 635
  90. lemma OAI.PettyProjection.Spherical.radiusPolynomial_homogeneous line 639
  91. lemma OAI.PettyProjection.Spherical.laplacePolynomial_radius_mul line 644
  92. lemma OAI.PettyProjection.Spherical.laplacePolynomial_radius_mul_homogeneous line 657
  93. def OAI.PettyProjection.Spherical.radialCoefficient line 666

    Source documentation

    The nonzero radial coefficient in the finite Fischer decomposition.

    def radialCoefficient (n l j : ℕ) : ℝ := 2 * (j + 1 : ℕ) * (2 * l + 2 * (j + 1 : ℕ) + n - 2)
  94. lemma OAI.PettyProjection.Spherical.radialCoefficient_pos line 668
  95. lemma OAI.PettyProjection.Spherical.radius_pow_mul_homogeneous line 678
  96. lemma OAI.PettyProjection.Spherical.laplacePolynomial_radial_harmonic line 683
  97. lemma OAI.PettyProjection.Spherical.laplacePolynomial_smul line 703
  98. lemma OAI.PettyProjection.Spherical.laplacePolynomial_eq_zero_small line 707
  99. def OAI.PettyProjection.Spherical.fischerSpan line 718

    Source documentation

    Algebraic span of radius powers times homogeneous harmonics of fixed total degree.

    def fischerSpan (n d : ℕ) : Submodule ℝ (MvPolynomial (Fin n) ℝ) :=
    …
  100. lemma OAI.PettyProjection.Spherical.fischerSpan_le_homogeneous line 722
  101. lemma OAI.PettyProjection.Spherical.harmonic_mem_fischerSpan line 728
  102. lemma OAI.PettyProjection.Spherical.fischerSpan_laplace_preimage line 732
  103. lemma OAI.PettyProjection.Spherical.homogeneous_mem_fischerSpan line 753

    Source documentation

    Finite Fischer decomposition: the induction on the degree.

    lemma homogeneous_mem_fischerSpan {n : ℕ} (hn : 2 ≤ n) (d : ℕ)
        {p : MvPolynomial (Fin n) ℝ} (hp : p.IsHomogeneous d) : p ∈ fischerSpan n d := by
    …

    Mentions: OAI.PettyProjection.Spherical.fischerSpan

  104. def OAI.PettyProjection.Spherical.polynomialRestriction line 769

    Source documentation

    Actual polynomial restrictions, as continuous functions on the sphere.

    def polynomialRestriction (n : ℕ) : MvPolynomial (Fin n) ℝ →ₐ[ℝ] C(Sphere n, ℝ) where
    …

    Mentions: OAI.PettyProjection.Spherical.Sphere

  105. lemma OAI.PettyProjection.Spherical.polynomialRestriction_apply line 784
  106. lemma OAI.PettyProjection.Spherical.polynomialRestriction_radius line 787
  107. lemma OAI.PettyProjection.Spherical.polynomialRestriction_separates line 792
  108. lemma OAI.PettyProjection.Spherical.polynomialRestriction_dense line 803
  109. def OAI.PettyProjection.Spherical.polynomialL2 line 811
  110. lemma OAI.PettyProjection.Spherical.polynomialL2_dense line 814
  111. def OAI.PettyProjection.Spherical.laplaceLinear line 818
  112. def OAI.PettyProjection.Spherical.harmonicPolynomials line 823
  113. instance OAI.PettyProjection.Spherical.harmonicPolynomials_finite line 826
  114. def OAI.PettyProjection.Spherical.harmonicSpace line 833

    Source documentation

    The genuine homogeneous harmonic subspaces of spherical L².

    def harmonicSpace (n d : ℕ) [NeZero n] : Submodule ℝ (H n) :=
    …

    Mentions: OAI.PettyProjection.Spherical.H

  115. instance OAI.PettyProjection.Spherical.harmonicSpace_finite line 836
  116. lemma OAI.PettyProjection.Spherical.harmonicSpace_orthogonal line 840
  117. lemma OAI.PettyProjection.Spherical.polynomialL2_mem_iSup_of_fischer line 851
  118. lemma OAI.PettyProjection.Spherical.polynomialL2_mem_iSup line 865
  119. lemma OAI.PettyProjection.Spherical.harmonicSpace_total line 875

    Source documentation

    Completeness under the actual measure, using Stone--Weierstrass and finite Fischer decomposition, with no assumed spectral interface.

    lemma harmonicSpace_total {n : ℕ} (hn : 2 ≤ n) [NeZero n] :
        (⨆ l, harmonicSpace n l).topologicalClosure = ⊤ := by
    …

    Mentions: OAI.PettyProjection.Spherical.harmonicSpace

  120. lemma OAI.PettyProjection.Spherical.energy_add_right line 882
  121. lemma OAI.PettyProjection.Spherical.energy_add_left line 901
  122. lemma OAI.PettyProjection.Spherical.rotDeriv_const_mul line 906
  123. lemma OAI.PettyProjection.Spherical.energy_const_mul_right line 913
  124. lemma OAI.PettyProjection.Spherical.energy_const_mul_left line 919
  125. lemma OAI.PettyProjection.Spherical.energy_sub_self line 924
  126. lemma OAI.PettyProjection.Spherical.energy_zero_right line 937
  127. lemma OAI.PettyProjection.Spherical.energy_finset_sum_right line 940
  128. lemma OAI.PettyProjection.Spherical.energy_harmonic_right line 952

    Source documentation

    Integration by parts against each genuine harmonic eigenfunction.

    lemma energy_harmonic_right {n d : ℕ} [NeZero n] {f : Space n → ℝ}
        {p : MvPolynomial (Fin n) ℝ} (hf : ContDiff ℝ 1 f) (hp : p.IsHomogeneous d)
        (hΔp : laplacePolynomial p = 0) :
        energy f (polynomialFunction p) = eigenvalue n d *
          mean (fun u : Sphere n => f u * polynomialFunction p u) := by
    …

    Mentions: OAI.PettyProjection.Spherical.Space, OAI.PettyProjection.Spherical.laplacePolynomial, OAI.PettyProjection.Spherical.energy, OAI.PettyProjection.Spherical.polynomialFunction, OAI.PettyProjection.Spherical.eigenvalue, OAI.PettyProjection.Spherical.mean, OAI.PettyProjection.Spherical.Sphere

  129. lemma OAI.PettyProjection.Spherical.polynomialFunction_smul_argument line 963
  130. lemma OAI.PettyProjection.Spherical.harmonicSpace_zero_constant line 974
  131. lemma OAI.PettyProjection.Spherical.constant_mem_harmonicSpace_zero line 988
  132. lemma OAI.PettyProjection.Spherical.harmonicSpace_zero_projection line 997