Tang, Shanjian; Zhang, Xu Null controllability for forward and backward stochastic parabolic equations. (English) Zbl 1203.93027 SIAM J. Control Optim. 48, No. 4, 2191-2216 (2009). Summary: This paper is concerned with the null controllability for general forward and backward linear stochastic parabolic equations. To develop the duality argument, we establish observability estimates for linear backward and forward stochastic parabolic equations with general coefficients, by means of a global Carleman estimate. Our Carleman inequality (Theorem 6.1) and observability estimate (Theorem 2.3) for backward stochastic parabolic equations are new in their forms. By adding a control variable to act on the white noise, we give a partial solution to the null controllability of forward stochastic heat equations, which was regarded as a challenging topic (see pages 99 and 108–110 in [V. Barbu, A. Răşcanu and G. Tessitore, Appl. Math. Optimization 47, No. 2, 97–120 (2003; Zbl 1087.93011]). Cited in 2 ReviewsCited in 56 Documents MSC: 93B05 Controllability 93B07 Observability 93E20 Optimal stochastic control 60H15 Stochastic partial differential equations (aspects of stochastic analysis) Keywords:null controllability; forward and backward linear stochastic parabolic equations; observability; global Carleman estimate Citations:Zbl 1087.93011 PDFBibTeX XMLCite \textit{S. Tang} and \textit{X. Zhang}, SIAM J. Control Optim. 48, No. 4, 2191--2216 (2009; Zbl 1203.93027) Full Text: DOI