Backward Stochastic Volterra integral equations driven by G-Brownian motion
Bingru Zhao, Mingshang Hu
TL;DR
This work extends backward stochastic Volterra integral equations to the nonlinear $G$-expectation setting, formulating $G$-BSVIEs driven by $G$-Brownian motion to capture volatility and model uncertainty. A novel backward iteration scheme constructs local Picard sequences on subintervals of $[0,T]$ and then stitches them to a global solution, with existence, uniqueness, and continuity proven via $G$-stochastic analysis and monotone convergence. A comparison theorem is established under suitable monotonicity, providing a tool for risk-sensitive stochastic control and dynamic risk measures under nonlinear expectations. The results deliver a rigorous well-posedness framework for $G$-BSVIEs, enabling applications in stochastic control under volatility ambiguity and robust utility models.
Abstract
In this paper, we study the Backward stochastic Volterra integral equation driven by G-Brownian motion (G-BSVIE). By adopting a different backward iteration method, we construct the approximating sequences on each local interval. With the help of G-stochastic analysis techniques and the monotone convergence theorem, the existence, uniqueness, and continuity of the solution over the entire interval are established. Moreover, we derive the comparison theorem.
