Let $P = (\Omega, \mathcal{F}, \mathbb{P})$ be a D1159: Probability space such that

(i)	$\mathfrak{L}^2 = \mathfrak{L}^2 (P \to \mathbb{C})$ is a D3083: Set of P-integrable random complex numbers on $P$

The complex Lebesgue inner product on $\mathfrak{L}^2$ is the D4881: Complex function \begin{equation} \mathfrak{L}^2 \times \mathfrak{L}^2 \to \mathbb{C}, \quad (X, Y) \mapsto \mathbb{E}( X \bar{Y} ) \end{equation}