OAI/Analysis/AffineBernstein/SphereIsometry.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.AffineBernstein.linearIsometrySphereHomeomorph line 15
  2. lemma OAI.AffineBernstein.linearIsometrySphereHomeomorph_coe line 19
  3. lemma OAI.AffineBernstein.linearIsometrySphere_cone_preimage line 23
  4. theorem OAI.AffineBernstein.linearIsometrySphere_measurePreserving line 47

    Source comment

    The Haar-induced sphere measure is preserved by every linear isometry. No surface-measure normalization or Jacobian identity is assumed.
    theorem linearIsometrySphere_measurePreserving (f : E ≃ₗᵢ[ℝ] F) :
        MeasurePreserving (linearIsometrySphereHomeomorph f)
          (volume : Measure E).toSphere (volume : Measure F).toSphere := by
    …

    Mentions: OAI.AffineBernstein.linearIsometrySphereHomeomorph