## The Annals of Applied Probability

### On well-posedness of forward–backward SDEs—A unified approach

#### Abstract

In this paper, we study the well-posedness of the Forward–Backward Stochastic Differential Equations (FBSDE) in a general non-Markovian framework. The main purpose is to find a unified scheme which combines all existing methodology in the literature, and to address some fundamental longstanding problems for non-Markovian FBSDEs. An important device is a decoupling random field that is regular (uniformly Lipschitz in its spatial variable). We show that the regulariy of such decoupling field is closely related to the bounded solution to an associated characteristic BSDE, a backward stochastic Riccati-type equation with superlinear growth in both components $Y$ and $Z$. We establish various sufficient conditions for the well-posedness of an ODE that dominates the characteristic BSDE, which leads to the existence of the desired regular decoupling random field, whence the solvability of the original FBSDE. A synthetic analysis of the solvability is given, as a “User’s Guide,” for a large class of FBSDEs that are not covered by the existing methods. Some of them have important implications in applications.

#### Article information

Source
Ann. Appl. Probab., Volume 25, Number 4 (2015), 2168-2214.

Dates
Revised: April 2014
First available in Project Euclid: 21 May 2015

https://projecteuclid.org/euclid.aoap/1432212440

Digital Object Identifier
doi:10.1214/14-AAP1046

Mathematical Reviews number (MathSciNet)
MR3349005

Zentralblatt MATH identifier
1319.60132

#### Citation

Ma, Jin; Wu, Zhen; Zhang, Detao; Zhang, Jianfeng. On well-posedness of forward–backward SDEs—A unified approach. Ann. Appl. Probab. 25 (2015), no. 4, 2168--2214. doi:10.1214/14-AAP1046. https://projecteuclid.org/euclid.aoap/1432212440

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