OAI/Geometry/EinsteinFour/ContinuousFieldDerivative.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Passing from derivatives along each initial frame to a derivative in the space of continuous fields. The fundamental theorem of calculus avoids any separate uniform remainder assumption.

  1. theorem OAI.PositiveEinsteinFour.Averages.continuousField_hasDerivAt line 25

    Source documentation

    A continuous family of pointwise derivatives is the derivative in the supremum norm on continuous fields.

    theorem continuousField_hasDerivAt {F G : ℝ → C(Ω, E)}
        (hG : Continuous G)
        (hpoint : ∀ t x, HasDerivAt (fun s => F s x) (G t x) t) (t : ℝ) :
        HasDerivAt F (G t) t := by
    …
  2. theorem OAI.PositiveEinsteinFour.Averages.continuousField_hasDerivAt_of_joint line 51

    Source documentation

    Joint continuity in time and the compact parameter gives exactly the continuity required by continuousField_hasDerivAt.

    theorem continuousField_hasDerivAt_of_joint {F G : ℝ → C(Ω, E)}
        (hG : Continuous (fun p : ℝ × Ω => G p.1 p.2))
        (hpoint : ∀ t x, HasDerivAt (fun s => F s x) (G t x) t) (t : ℝ) :
        HasDerivAt F (G t) t :=
    …