Isaacs equation and Bellman equation: Difference between pages
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The | The Bellman equation is the equality | ||
\[ \sup_{a \in \mathcal{A}} \ | \[ \sup_{a \in \mathcal{A}} \, L_a u(x) = f(x), \] | ||
where $ | where $L_a$ is some family of linear integro-differential operators indexed by an arbitrary set $\mathcal{A}$. | ||
The equation appears naturally in | The equation appears naturally in problems of stochastic control with [[Levy processes]]. | ||
The equation is [[uniformly elliptic]] with respect to any class $\mathcal{L}$ that contains all the operators $ | The equation is [[uniformly elliptic]] with respect to any class $\mathcal{L}$ that contains all the operators $L_a$. | ||
Note that any | Note that any '''convex''' fully nonlinear elliptic PDE of second order $F(D^2u, Du, u, x)$ can be written as a Bellman equation by taking the supremum of all supporting planes of $F$. It is not known whether that such representation holds for integro-differential equations. | ||
Revision as of 14:49, 27 May 2011
The Bellman equation is the equality \[ \sup_{a \in \mathcal{A}} \, L_a u(x) = f(x), \] where $L_a$ is some family of linear integro-differential operators indexed by an arbitrary set $\mathcal{A}$.
The equation appears naturally in problems of stochastic control with Levy processes.
The equation is uniformly elliptic with respect to any class $\mathcal{L}$ that contains all the operators $L_a$.
Note that any convex fully nonlinear elliptic PDE of second order $F(D^2u, Du, u, x)$ can be written as a Bellman equation by taking the supremum of all supporting planes of $F$. It is not known whether that such representation holds for integro-differential equations.