The actual smooth representative retains the proved compact spatial support of its L² class.
theorem
EulerCylinderSmoothOrbit.representative_zero_outside
(period : ℝ)
[Fact (0 < period)]
(S : Set EulerSmoothLimit.Space)
(hS : MeasurableSet S)
(hSc : IsClosed S)
(u : ↥(EulerLiftedGradientSpace.LiftL2 period))
(hu : SmoothOrbit period u)
(hs : u ∈ EulerLpCylinderPaths.Supported period EulerSmoothLimit.Space S hS)
(x : EulerLiftedGradientSpace.LiftDomain period)
(hx : x.1 ∉ S)
:
Vanishing outside a closed support region passes from the actual L² class to its smooth representative.
theorem
EulerCylinderSmoothOrbit.representative_tsupport_subset
(period : ℝ)
[Fact (0 < period)]
(S : Set EulerSmoothLimit.Space)
(hS : MeasurableSet S)
(hSc : IsClosed S)
(u : ↥(EulerLiftedGradientSpace.LiftL2 period))
(hu : SmoothOrbit period u)
(hs : u ∈ EulerLpCylinderPaths.Supported period EulerSmoothLimit.Space S hS)
:
tsupport (representative period u hu) ⊆ EulerLpCylinderTranslation.spatialSet period S
The actual topological support is contained in the same closed spatial support.
theorem
EulerCylinderSmoothOrbit.representative_hasCompactSupport
(period : ℝ)
[Fact (0 < period)]
(S : Set EulerSmoothLimit.Space)
(hS : MeasurableSet S)
(hSc : IsCompact S)
(u : ↥(EulerLiftedGradientSpace.LiftL2 period))
(hu : SmoothOrbit period u)
(hs : u ∈ EulerLpCylinderPaths.Supported period EulerSmoothLimit.Space S hS)
:
HasCompactSupport (representative period u hu)
Compact spatial support remains compact after adjoining the periodic angle.