2010/01/18 by Shizan Fang, Fang, Shizan, Dejun Luo +3
Computer Science · Economics, Econometrics and Finance · Mathematics · #34F05 (Secondary) #37C10 #60H10 (Primary) #60J60 #Advanced Mathematical Modeling in Engineering #FOS: Mathematics #Nonlinear Partial Differential Equations #Probability (math.PR) #Stochastic processes and financial applications
paper · pdf · doi:10.48550/arxiv.1001.3007
openalex publication_date 2010/01/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider Itô SDE \d Xt=∑j=1m Aj(Xt) \d wtj + A0(Xt) \d t on \Rd. The diffusion coefficients A1,..., Am are supposed to be in the Sobolev space Wloc1,p (\Rd) with p>d, and to have linear growth; for the drift coefficient A0, we consider two cases: (i) A0 is continuous whose distributional divergence δ(A0) w.r.t. the Gaussian measure γd exists, (ii) A0 has the Sobolev regularity Wloc1,p' for some p'>1. Assume ∫\Rd exp[λ0(|δ(A0)| + ∑j=1m (|δ(Aj)|2 +|∇ Aj|2))] \dγd0, in the case (i), if the pathwise uniqueness of solutions holds, then the push-forward (Xt)_# γd admits a density with respect to γd. In particular, if the coefficients are bounded Lipschitz continuous, then Xt leaves the Lebesgue measure \Lebd quasi-invariant. In the case (ii), we develop a method used by G. Crippa and C. De Lellis for ODE and implemented by X. Zhang for SDE, to establish the existence and uniqueness of stochastic flow of maps.