We deal with nonlinear elliptic and parabolic systems that are the Bellman like systems associated to stochastic differential games with mean field dependent dynamics. The key novelty of the paper is that we allow heavily mean field dependent dynamics. This in particular leads to a system of PDE's with critical growth, for which it is rare to have an existence and/or regularity result. In the paper, we introduce a structural assumptions that cover many cases in stochastic differential games with mean filed dependent dynamics for which we are able to establish the existence of a weak solution. In addition, we present here a completely new method for obtaining the maximum/minimum principles for systems with critical growths, which is a starting point for further existence and also qualitative analysis.
翻译:我们处理的是非线性椭圆形和抛物线系统,这些是贝尔曼系统,类似于与中度田间依附动态的随机差异游戏相关联的系统。本文的关键新颖之处是,我们允许大量中度地依附实地动态。这特别导致一个具有关键增长的PDE系统,其存在和/或规律性结果很少见。在文件中,我们引入了一个结构假设,它覆盖了随机差异游戏中的许多案例,其中含有我们能够确定存在弱度解决方案的中度自存动态。此外,我们在这里提出了获得具有关键增长的系统的最大/最小原则的全新方法,这是进一步存在和定性分析的起点。