Archimedes' angular marginal #
The height coordinate of uniform sphere probability is uniform on [-1,1].
Archimedes' hat-box identity for every Euclidean unit direction.
theorem
LiebThirring.sphereHeight_uniform :
MeasureTheory.Measure.map (fun (ω : ↑(Metric.sphere 0 1)) => (↑ω).ofLp 2) unitSphereMeasure = (ENNReal.ofReal 2)⁻¹ • MeasureTheory.volume.restrict (Set.Icc (-1) 1)
The height coordinate of uniform sphere probability is uniform on [-1,1].
theorem
LiebThirring.unitSphereMeasure_inner_uniform
(e : Position)
(he : ‖e‖ = 1)
:
MeasureTheory.Measure.map (fun (ω : ↑(Metric.sphere 0 1)) => inner ℝ (↑ω) e) unitSphereMeasure = (ENNReal.ofReal 2)⁻¹ • MeasureTheory.volume.restrict (Set.Icc (-1) 1)
Archimedes' hat-box identity for every Euclidean unit direction.