Mean-field games of controls with reflected state processes

Establish a general theory of mean-field games of controls in the presence of reflected state processes, including existence and characterization results beyond the specific reflected Stackelberg pollution model considered here.

Background

Mean-field games of controls differ from standard mean-field games because the population distribution depends on the agents’ control processes rather than only on their state distributions. Introducing state reflection imposes a hard state constraint through a regulating or local-time process, creating additional analytical difficulties in the associated stochastic control and equilibrium problems. The introduction notes that prior work has addressed reflected diffusions and some mean-field models, but that the combination of control-based mean-field interaction and reflected state dynamics remains unresolved in general.

The paper develops a particular finite-horizon mean-field Stackelberg game for production and carbon-emission reduction with a reflected cumulative-emission state. It constructs an approximate Nash equilibrium for heterogeneous followers and an approximate Stackelberg equilibrium for the leader, thereby addressing a specialized instance of the broader unresolved problem rather than providing a general theory for all mean-field games of controls with reflected states.

References

Despite these advancements, the study of MFGs of controls in the presence of reflected state processes remains an open problem.

Mean Field Stackelberg Game for Production and Carbon Emission Reduction with State Reflections  (2608.12775 - Bo et al., 13 Aug 2026) in Section 1, Introduction