`BookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonal` (v x : Fin 4 → ℝ) (hx : ∑ a, lower v a * x a = 0) : (spatialProj v).mulVec x = x
ProvedBookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonaltheoremstimepiece
Prove the following Lean 4 theorem from ChapterGravityProjector.
BookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonal (v x : Fin 4 → ℝ) (hx : ∑ a, lower v a * x a = 0) : (spatialProj v).mulVec x = x
Formalization note: Lean 4 identifier BookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonal.
Preamble
-- Generated from ChapterGravityProjector.lean — theorem BookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonal import Mathlib import Definitions.Def_ChapterGravityProjector open BookProof.ChapterGravityProjector open Matrix open scoped BigOperators
Formal statement
theorem BookProof.ChapterGravityProjector.spatialProj_mulVec_of_orthogonal (v x : Fin 4 → ℝ)
(hx : ∑ a, lower v a * x a = 0) :
(spatialProj v).mulVec x = x := by sorry