English
For HasCondSubgaussianMGF h, the almost-everywhere bound on the mgf under condExpKernel holds with respect to μ.
Русский
Для HasCondSubgaussianMGF h почти повсюду выполняется неравенство mgf под condExpKernel относительно μ.
LaTeX
$$ae (HasCondSubgaussianMGF.mgf_le h) (condExpKernel μ m)$$
Lean4
theorem ae_trim_condExp_le (h : HasCondSubgaussianMGF m hm X c μ) (t : ℝ) :
∀ᵐ ω' ∂(μ.trim hm), (μ[fun ω ↦ exp (t * X ω)|m]) ω' ≤ exp (c * t ^ 2 / 2) :=
by
have h_eq := condExp_ae_eq_trim_integral_condExpKernel hm (h.integrable_exp_mul t)
simp_rw [condExpKernel_comp_trim] at h_eq
filter_upwards [h.mgf_le, h_eq] with ω' h_mgf h_eq
rw [h_eq]
exact h_mgf t