A complex Feynman-Kac formula via linear backward stochastic differential equations

A complex notion of backward stochastic differential equation (BSDE) is proposed in this paper to give a probabilistic interpretation for linear first order complex partial differential equation (PDE). By the uniqueness and existence of regular solutions to complex BSDE, we deduce that there exists a unique classical solution $\{\mathbb{U}(t,x)$ to complex PDE and $\{\mathbb{U}(t,x)$ is analytic in $x$ for each $t$. Thus we extend the well known real Feynman-Kac formula to a complex version. It is stressed that our complex BSDE corresponds to a linear PDE without the second order term.