{ "id": "2006.12993", "version": "v1", "published": "2020-06-19T22:49:13.000Z", "updated": "2020-06-19T22:49:13.000Z", "title": "Mean Field Games of Controls: on the convergence of Nash equilibria", "authors": [ "Mao Fabrice Djete" ], "categories": [ "math.PR" ], "abstract": "In this paper, we investigate a class of mean field games where the mean field interactions are achieved through the joint (conditional) distribution of the controlled state and the control process. The strategies are of $open\\;loop$ type, and the volatility coefficient $\\sigma$ can be controlled. Using (controlled) Fokker-Planck equations, we introduce a notion of measure-valued solution of mean-field games of controls, and through convergence results, prove a relation between these solutions on the one hand, and the $\\epsilon_N$--Nash equilibria on the other hand. It is shown that $\\epsilon_N$--Nash equilibria in the $N$--player games have limits as $N$ tends to infinity, and each limit is a measure-valued solution of the mean-field games of controls. Conversely, any measure-valued solution can be obtained as the limit of a sequence of $\\epsilon_N$--Nash equilibria in the $N$--player games. In other words, the measure-valued solutions are the accumulating points of $\\epsilon_N$--Nash equilibria. Similarly, by considering an $\\epsilon$--strong solution of mean field games of controls which is the classical strong solution where the optimality is obtained by admitting a small error $\\epsilon,$ we prove that the measure-valued solutions are the accumulating points of this type of solutions when $\\epsilon$ goes to zero. Finally, existence of measure-valued solution of mean-field games of controls are proved in the case without common noise.", "revisions": [ { "version": "v1", "updated": "2020-06-19T22:49:13.000Z" } ], "analyses": { "keywords": [ "mean field games", "nash equilibria", "measure-valued solution", "mean-field games", "player games" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }