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BGW.Skorokhod.ProductPaths

Pairing a càdlàg path with a continuous path #

The pair of a càdlàg real path and a continuous real path is a càdlàg path with values in ℝ × ℝ. The pairing map is jointly continuous for the Skorokhod J1 topology and the uniform topology on continuous paths. The same time changes control both coordinates; in the continuous coordinate one also uses uniform convergence and uniform continuity of the limiting path.

Reference: P. Billingsley, Convergence of Probability Measures, 2nd ed., Wiley, 1999, Section 12.

def BGW.Skorokhod.prodCont {T : ℝ} (f : D T ℝ) (g : C(↑(Set.Icc 0 T), ℝ)) :
D T (ℝ × ℝ)

The pair path (f, g) of a càdlàg path and a continuous path.

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Instances For
    def BGW.Skorokhod.prodWithCont {T : ℝ} {E : Type u_1} {F : Type u_2} [MetricSpace E] [MetricSpace F] (f : D T E) (g : C(↑(Set.Icc 0 T), F)) :
    D T (E × F)

    The pair path (f, g) of a càdlàg path with values in E and a continuous path with values in F.

    Equations
    Instances For
      @[simp]
      theorem BGW.Skorokhod.prodWithCont_apply {T : ℝ} {E : Type u_1} {F : Type u_2} [MetricSpace E] [MetricSpace F] (f : D T E) (g : C(↑(Set.Icc 0 T), F)) (t : ↑(Set.Icc 0 T)) :
      (prodWithCont f g) t = (f t, g t)
      theorem BGW.Skorokhod.continuous_prodWithCont {T : ℝ} {E : Type u_1} {F : Type u_2} [MetricSpace E] [MetricSpace F] :
      Continuous fun (p : D T E × C(↑(Set.Icc 0 T), F)) => prodWithCont p.1 p.2

      prodWithCont is jointly continuous on D_T(E) × C([0,T], F) (Skorokhod J1 topology and uniform topology).

      theorem BGW.Skorokhod.continuous_prodCont {T : ℝ} :
      Continuous fun (p : D T ℝ × C(↑(Set.Icc 0 T), ℝ)) => prodCont p.1 p.2

      prodCont is jointly continuous on D_T(ℝ) × C([0,T],ℝ).

      theorem BGW.Skorokhod.tendsto_prodCont {T : ℝ} {ι : Type u_1} {l : Filter ι} {u : ι → D T ℝ} {f : D T ℝ} {v : ι → C(↑(Set.Icc 0 T), ℝ)} {g : C(↑(Set.Icc 0 T), ℝ)} (hu : Filter.Tendsto u l (nhds f)) (hv : Filter.Tendsto v l (nhds g)) :
      Filter.Tendsto (fun (i : ι) => prodCont (u i) (v i)) l (nhds (prodCont f g))

      Sequential form of continuous_prodCont.