Time periodic solutions of first order mean field games from the perspective of Mather theory
Panrui Ni
TL;DR
This work addresses the existence of non-trivial time-periodic solutions for first-order mean field games with a monotone, spatially homogeneous coupling and a fixed horizon. It leverages weak KAM and Aubry–Mather theory to relate long-time dynamics to Mather’s minimal measures, proving the existence of time-periodic states when a non-trivial periodic orbit lies in the Mather set. The results establish regularity, uniqueness up to constants, and Lipschitz dependence of the spectral parameter $c(m_T)$, along with large-time convergence of solutions to the periodic regime. A concrete torus example illustrates a smooth time-periodic solution, highlighting the connection between MFG dynamics and minimal-measure geometry. These findings deepen the understanding of long-time behavior in MFGs by tying it to Mather theory and the structure of minimal measures.
Abstract
In this paper, the existence of non-trivial time periodic solutions of first order mean field games is proved. It is assumed that there is a non-trivial periodic orbit contained in the Mather set. The whole system is autonomous with a monotonic coupling term. Moreover, the large time convergence of solutions of first order mean field games to time periodic solutions is also considered.
