The low-order estimates behind source (20). The upper quadratic-form bound uses only the negative part of the angular derivative. Its cost therefore retains the narrow-profile factor which is absent from the absolute Hessian bound.
@[reducible, inline]
Matrix: an abbreviation for Space →L[ℝ] Space.
Equations
Instances For
noncomputable def
EulerPacketPhysicalLowBounds.shearTerm
(amp slope : ℝ)
(r w : EulerSmoothLimit.Space)
:
Shear term, given by (amp*slope) • rankOne ℝ w r.
Equations
- EulerPacketPhysicalLowBounds.shearTerm amp slope r w = (amp * slope) • ((InnerProductSpace.rankOne ℝ) w) r
Instances For
noncomputable def
EulerPacketPhysicalLowBounds.pressureTerm
(amp slope : ℝ)
(M : Matrix)
(r w : EulerSmoothLimit.Space)
:
Pressure term, given by (-2*amp*⟪r,M w⟫_ℝ*slope/‖r‖^2) • rankOne ℝ r r.
Equations
Instances For
theorem
EulerPacketPhysicalLowBounds.pressureTerm_nonpos
(amp slope : ℝ)
(M : Matrix)
(r w z : EulerSmoothLimit.Space)
(hamp : 0 ≤ amp)
(hslope : 0 ≤ slope)
(hflux : 0 ≤ inner ℝ r (M w))
:
theorem
EulerPacketPhysicalLowBounds.good_step_bounds
(A B H J M : Matrix)
(r w : EulerSmoothLimit.Space)
(amp δ θ ev ep V P K size : ℝ)
(hamp : 0 ≤ amp)
(hδ : 0 < δ)
(hδ1 : δ ≤ 1)
(hsize : amp * (‖r‖ * ‖w‖) ≤ δ * size)
(hM : ‖M‖ ≤ V)
(hB : ‖B‖ ≤ P)
(hJ : ‖J‖ ≤ K)
(hev : ‖A - B - shearTerm amp (deriv (EulerPeriodicProfile.profile δ) θ) r w‖ ≤ ev)
(hep : ‖H - J - pressureTerm amp (deriv (EulerPeriodicProfile.profile δ) θ) M r w‖ ≤ ep)
(hflux : 0 ≤ inner ℝ r (M w))
(Kupper : ℝ)
(hupper : ∀ (z : EulerSmoothLimit.Space), inner ℝ (J z) z ≤ Kupper * ‖z‖ ^ 2)
:
On a good interval the upper pressure cost uses ampsize, whereas absolute velocity and Hessian costs use ampsize/delta.
theorem
EulerPacketPhysicalLowBounds.absolute_step_bounds
(A B H J M : Matrix)
(r w : EulerSmoothLimit.Space)
(amp δ θ ev ep V P K size : ℝ)
(hamp : 0 ≤ amp)
(hδ : 0 < δ)
(hδ1 : δ ≤ 1)
(hsize : amp * (‖r‖ * ‖w‖) ≤ δ * size)
(hM : ‖M‖ ≤ V)
(hB : ‖B‖ ≤ P)
(hJ : ‖J‖ ≤ K)
(hev : ‖A - B - shearTerm amp (deriv (EulerPeriodicProfile.profile δ) θ) r w‖ ≤ ev)
(hep : ‖H - J - pressureTerm amp (deriv (EulerPeriodicProfile.profile δ) θ) M r w‖ ≤ ep)
(Kupper : ℝ)
(hupper : ∀ (z : EulerSmoothLimit.Space), inner ℝ (J z) z ≤ Kupper * ‖z‖ ^ 2)
:
Without a sign assertion the same absolute estimate controls the positive Hessian cost. This is used on history and early forward times.