English
For any dt, IsMIntegralCurve γ v is equivalent to IsMIntegralCurve (γ ∘ (·+dt)) v; i.e., shifting the time parameter does not affect the status of being an integral curve.
Русский
Для любого dt равенство IsMIntegralCurve γ v ⇔ IsMIntegralCurve (γ ∘ (·+dt)) v: сдвиг времени не меняет статус интегральной кривой.
LaTeX
$$$IsMIntegralCurve(\\gamma, v) \\iff IsMIntegralCurve(\\gamma \\circ (\\cdot + dt), v)$$$
Lean4
theorem isMIntegralCurve_comp_add {dt : ℝ} : IsMIntegralCurve γ v ↔ IsMIntegralCurve (γ ∘ (· + dt)) v :=
by
refine ⟨fun hγ ↦ hγ.comp_add _, fun hγ ↦ ?_⟩
convert hγ.comp_add (-dt)
ext t
simp only [Function.comp_apply, neg_add_cancel_right]