Exact conservation of kinetic energy for the ordinary smooth Euler class, using the genuine noncompact transport and pressure cancellations.
theorem
EulerOrdinarySobolev.Evolution.kineticEnergy_hasDerivWithinAt
{T : ℝ}
{hT : 0 ≤ T}
(U : Evolution T hT)
(t : ↑(Set.Icc 0 T))
:
HasDerivWithinAt (fun (r : ℝ) => ‖(U.velocity (Set.projIcc 0 T hT r)).toLp‖ ^ 2) 0 (Set.Icc 0 T) ↑t